Geographical Abstracts: Physical Geography - Online sample copy

GEOGRAPHICAL ABSTRACTS: PHYSICAL GEOGRAPHY
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RECORD FORMAT
Chapter heading
PALAEONTOLOGY
Sub-chapter heading
Palaeobotany
Title of article in English
Item number
11726 Santa Lucia superiore (Toirano, Liguria):
Ligurian vegetation history during the Lower
Pleniglacial (French)
Non-English title
(Santa Lucia superiore (Toirano, Ligurie): Reconstitution
locale de la vГ©gГ©tation ligure durant le PlГ©niglaciaire ancien)
Author name(s)
Kaniewski D., Renault-Miskovsky J., Tozzi C. and de Lumley
H.
Journal title
Geobios 2005 39/3 (353-364)
Page numbers of the article
in the original journal
Year of publication, volume
number and issue number
Abstract in English
Article language
Pollen analysis of Santa Lucia superiore cave (Italy) reports
at local scale the lowland Ligurian vegetation during the
Lower Pleniglacial (75 to 57 Kyr BP). The pollen profile
shows two AP extensions during a steppe-landscape episode
in Liguria. The dry and cold phases caused the establishment
of a steppe-landscape (NAP 92%) with Artemisia, Ephedra,
Poaceae and Chenopodiaceae, similar to those mentioned in
the Latium during the Pleniglacial. The increase of moisture
generated a first arboreal extension (Pinus, Betula, Corylus,
Ulmus), which engendered the formation of an open-forest
landscape (AP 43%). The second arboreal extension (AP
55%) was due to an increase of moisture and higher temperatures, which allowed the development of Mediterranean trees
and shrubs (Quercus ilex, Olea, Phillyrea). This warming up
occurred probably simultaneously with a secondary transgression during the glacial sea-level change. The upper part
of the profile shows an open vegetation, which indicates the
return of a steppe-landscape. Pollen data, replaced in the
multidisciplinary studies of the site, are well correlated with
the fauna and sediment data. E 2005 Elsevier SAS. All rights
reserved.
GEOGRAPHICAL ABSTRACTS: PHYSICAL GEOGRAPHY
CONTENTS
Page
SYNOPTIC GEOGRAPHY
Global change
Pollution
Biogeochemical cycles
Modelling and numerical methods
International programmes
265
265
-
LANDFORMS
Weathering and related landforms
Fluvial landforms
Coastal landforms
Volcanic landforms
Arid landforms
Regional physiography
Neotectonics and structural control
Landforms of other planets
Slopes
Soil mechanics
Karst
Anthropogenic landforms
267
267
270
271
271
272
273
274
276
277
278
THE QUATERNARY
Chronology
Palaeoclimatology
Oceans
Tropics and sub-tropics
Mid-latitude and extra-glacial
Glacial landforms and sediments
The Holocene
Sea level
Periglacial
Glaciology
278
280
289
293
293
294
295
297
297
SEDIMENTOLOGY
Methods, equipment and programs
Sediments and sedimentary processes - physical properties
Sediments and sedimentary processes - transport
Sediments and sedimentary processes - deposition
Sediments and sedimentary processes - diagenesis
Sedimentary geochemistry
Sedimentary environments - terrestrial
Sedimentary environments - coastal and shallow marine
Sedimentary environments - oceanic
Applied sedimentology
302
302
305
312
313
315
317
318
318
SOILS
Regional and survey
Methods
Genesis and formation
Physical properties
Soil water
Mineralogy
Chemistry
Organic matter
Biota
Contamination and remediation
Erosion and conservation
320
321
322
324
326
329
336
341
347
354
HYDROLOGY
Precipitation assessment
Precipitation quality
Interception, throughfall and stemflow
Evaporation and transpiration
359
360
363
364
365
continued on next page
Runoff, streamflow and basins
Channel hydraulics and sediment transport
Lakes and reservoirs
Wetlands and estuaries
Surface water quality
runoff and soil water
rivers and streams
lakes and reservoirs
Groundwater processes
vadose zone
phreatic zone
Groundwater quality
vadose zone
phreatic zone
Glacial hydrology
Land use, forestry and agriculture
Water resources and management
METEOROLOGY AND CLIMATOLOGY
Instrumentation
Radiation
Atmospheric electricity
Optics
Regional weather patterns
Synoptic meteorology
Boundary layer meteorology
Air-sea interaction
Dynamic meteorology
large scale
mesoscale
Convection and cloud microphysics
Rainfall processes
Weather and climate forecasting
Climate change
Atmospheric chemistry
Aerosols
Atmospheric pollution
367
383
388
389
391
395
399
407
409
412
414
417
422
423
426
427
429
434
436
437
441
443
444
449
455
456
461
463
467
468
472
477
484
495
REMOTE SENSING, GIS AND MAPPING
Remote sensing
primary data capture
secondary data capture
geodesy
numerical and image analysis
GIS
methodology
error, accuracy, quality, legislation
software and systems
Mapping
Map curatorship and history
Cartography
Applications
atmosphere
lithosphere
biosphere
hydrosphere
human
518
520
521
526
528
GENERAL TEXTS
529
508
509
509
512
516
516
516
517
517
265
SYNOPTIC GEOGRAPHY
Global change
1401 Salt lakes in Australia: Present problems and prognosis for the future
Timms B.V. Hydrobiologia 2005 552/1 (1-15)
Australia is a land of salt lakes and despite low human population
density, many lakes are adversely impacted by a range of factors.
Secondary salinisation is the most pernicious force degrading
lakes, especially in south-west Western Australia where up to
30% of the landscape is predicted to be affected. Mining also
impinges on many salt lakes in this state, mainly through the
dewatering of saline groundwater. Exploitation of groundwater
for irrigation caused some lakes in Victoria, Australia, to dry,
especially the significant Red Rock Complex. Global climate
change will result in new water balances in endorheic lakes, with
most having less water, particularly the seasonal lakes of southern Australia. This has already happened in Lake Corangamite,
Victoria, but the prime reason is diversion of inflowing floodwater. Consequently, the lake has retreated and become salinised
compromising its status as a Ramsar site. Various other lakes suffer from enhanced sedimentation, have introduced biota or their
catchments are being disturbed to their detriment. Enlightened
management should be able to maintain some important lakes in
an acceptable condition, but, for most others, the future is bleak.
В© Springer 2005.
1402 Assessing the future global impacts of ozone on
vegetation
Ashmore M.R. Plant, Cell and Environment 2005 28/8 (949-964)
Ozone is a major secondary air pollutant, the current concentrations of which have been shown to have significant adverse
effects on crop yields, forest growth and species composition.
In North America and Europe, emissions of ozone precursors
are decreasing but in other regions of the world, especially Asia,
where much less is known about its impacts, they are increasing rapidly. There is also evidence of an increase in global
background ozone concentrations, which will lead to significant
changes in global ozone exposure over this century, during which
direct and indirect effects of other changes in the global atmosphere will also modify plant responses to ozone. This paper
considers how far our current understanding of the mechanisms
of ozone impacts, and the tools currently used for ozone risk
assessment, are capable of evaluating the consequences of these
changing global patterns of exposure to ozone. Risk assessment
based on relationships between external concentration and plant
response is inadequate for these new challenges. New models
linking stomatal flux, and detoxification and repair processes, to
carbon assimilation and allocation provide a more mechanistic
basis for future risk assessments. However, there are a range of
more complex secondary effects of ozone that are not considered in current risk assessment, and there is an urgent need to
develop more holistic approaches linking the effects of ozone,
climate, and nutrient and water availability, on individual plants,
species interactions and ecosystem function. В© 2005 Blackwell
Publishing Ltd.
1403 The cryosphere and global environmental change:
Some geomorphic perspectives
Slaymaker O. Chikei/Transactions, Japanese Geomorphological
Union 2005 26/4 (359-370)
A consideration of the global environmental changes affected by
the cryosphere. The components of the terrestrial cryosphere
(glaciers, snow, permafrost and lake and river ice) are analysed
independently and also in the context of their influence on, and
response to human activity in, large river basins tributary to the
Arctic Ocean. Some of the geomorphic concepts that are thought
to be important in interpreting these cryospheric changes are:
thresholds, systems, complex response, resistance, panarchy, collapse and YatsuвЂ™s idea that "anything goes ".
Biogeochemical cycles
1404 Effect of potassium phosphate fertilization on production and emission of methane and its 13 C-stable isotope
composition in rice microcosms
Conrad R. and Klose M. Soil Biology and Biochemistry 2005
37/11 (2099-2108)
Rice fields are an important source for atmospheric CH4 , but
the effects of fertilization are not well known. We studied the
turnover of CH 4 in rice soil microcosms without and with addition of potassium phosphate. Height and tiller number of rice
plants were higher in the fertilized than in the unfertilized microcosms. Emission rates of CH4 were also higher, but porewater
concentrations of CH4 were lower. The 13 C values of the emitted
CH4 and of the CH 4 in the porewater were both 2-6% higher in
the fertilized microcosms than in the control. Potassium phosphate did not affect rate and isotopic signature of CH4 production
in anoxic soil slurries. On the other hand, roots retrieved from
fertilized microcosms at the end of incubation exhibited slightly
higher CH4 production rates and slightly higher CH4 - 13 C values
compared to roots from unfertilized plants. Addition of potassium phosphate to excised rice roots generally inhibited CH4
production and resulted in increasingly lower 13 C values of the
produced CH4 . Fractionation of 13 C during plant ventilation
(i.e. 13 C in pore water CH4 versus CH4 emitted) was larger
in the fertilized microcosms than in the control. Besides plant
ventilation, this difference may also have been caused by CH4
oxidation in the rhizosphere. However, calculation from the
isotopic data showed that less than 27% of the produced CH4
was oxidized. Collectively, our results indicate that potassium
phosphate fertilization stimulated CH4 emission by enhancing
root methanogenesis, plant ventilation and/or CH4 oxidation, resulting in residence times of CH4 in the porewater in the order of
hours. В© 2005 Elsevier Ltd. All rights reserved.
1405 Enhanced iron reduction by iron supplement: A strategy to reduce methane emission from paddies
JВЁackel U., Russo S. and Schnell S. Soil Biology and Biochemistry
2005 37/11 (2150-2154)
As an option for mitigating methane emissions from rice paddies
the effects of ferrihydrite application to an experimental field
plot at the beginning of the growth season was studied. Methane
emissions during the vegetation period of rice were significantly
lower (50%) in the fertilized plot compared to the non-supplemented control plot. Although toxic effects of iron are known
to occur with wetland plants including rice, our field experiment
showed no deterioration of agrophysiological data. Grain yield,
harvest index, and iron content of grains were not different in
the two plots. Therefore, we propose that iron application is a
suitable strategy to reduce methane emission from rice paddies.
В© 2005 Elsevier Ltd. All rights reserved.
1406 Microbial responses and nitrous oxide emissions during wetting and drying of organically and conventionally
managed soil under tomatoes
Burger M., Jackson L.E., Lundquist E.J. et al. Biology and
Fertility of Soils 2005 42/2 (109-118)
The types and amounts of carbon (C) and nitrogen (N) inputs,
as well as irrigation management are likely to influence gaseous
emissions and microbial ecology of agricultural soil. Carbon
dioxide (CO2 ) and nitrous oxide (N2 O) efflux, with and without
acetylene inhibition, inorganic N, and microbial biomass C were
measured after irrigation or simulated rainfall in two agricultural fields under tomatoes (Lycopersicon esculentum). The two
fields, located in the California Central Valley, had either a history
of high organic matter (OM) inputs ("organic" management) or
one of low OM and inorganic fertilizer inputs ("conventional"
management). In microcosms, where short-term microbial responses to wetting and drying were studied, the highest CO2
efflux took place at about 60% water-filled pore space (WFPS).
At this moisture level, phospholipid fatty acids (PLFA) indicative
of microbial nutrient availability were elevated and a PLFA stress
indicator was depressed, suggesting peak microbial activity. The
highest N 2 O efflux in the organically managed soil (0.94 mg
N2 O-N m-2 h-1 ) occurred after manure and legume cover crop
266
SYNOPTIC GEOGRAPHY
incorporation, and in the conventionally managed soil (2.12 mg
N2 O-N m-2 h-1 ) after inorganic N fertilizer inputs. Elevated N2 O
emissions occurred at a WFPS >60% and lasted <2 days after
wetting, probably because the top layer (0-150 mm) of this silt
loam soil dried quickly. Therefore, in these cropping systems,
irrigation management might control the duration of elevated
N2 O efflux, even when C and inorganic N availability are high,
whereas inorganic N concentrations should be kept low during
times when soil moisture cannot be controlled.
1407 Methane release through resuspension of littoral
sediment
Bussmann I. Biogeochemistry 2005 74/3 (283-302)
Sediment in the littoral zone of lakes is frequently disturbed by
wave action or bioturbation, resulting in sediment resuspension.
In undisturbed sediment, methanotrophic bacteria efficiently reduce the diffusive flux of methane into the water column. In
a microcosm study, the resuspension of littoral sediment was
simulated in sediment cores for a winter (n = 3) and a summer
situation (n = 3). The erosion of surface sediment resulted in a
large flux of methane into the overlying water (207 176 mol
h -1 m-2 in winter and 73 18 mol h-1 m-2 in summer). Only
a minor part (16 7%) of the methane released was oxidized
by methanotrophic bacteria, whereas the major part escaped into
the water column. Only 6-16% of the littoral zone has to be
resuspended to reach the same flux as from undisturbed littoral
sediment. For the daily flux, a sediment resuspension has to last
1-4 h to reach the undisturbed daily flux. The study reveals the
important role of sediment resuspension in the littoral methane
cycle as an intense but variable source of methane of largely
unknown magnitude. В© Springer 2005.
1408 Short-term effects of clearfelling on soil CO2 , CH4 , and
N2 O fluxes in a Sitka spruce plantation
Zerva A. and Mencuccini M. Soil Biology and Biochemistry 2005
37/11 (2025-2036)
We examined the effects of forest clearfelling on the fluxes of soil
CO2 , CH4 , and N2 O in a Sitka spruce (Picea sitchensis (Bong.)
Carr.) plantation on an organic-rich peaty gley soil, in Northern
England. Soil CO2 , CH4 , N2 O as well as environmental factors
such as soil temperature, soil water content, and depth to the
water table were recorded in two mature stands for one growing
season, at the end of which one of the two stands was felled
and one was left as control. Monitoring of the same parameters
continued thereafter for a second growing season. For the first
10 months after clearfelling, there was a significant decrease in
soil CO2 efflux, with an average efflux rate of 4.0 g m-2 d-1 in the
mature stand (40-year) and 2.7 g m -2 d-1 in clearfelled site (CF).
Clearfelling turned the soil from a sink (-0.37 mg m-2 d-1 ) for CH4
to a net source (2.01 mg m-2 d-1 ). For the same period, soil N2 O
fluxes averaged 0.57 mg m-2 d-1 in the CF and 0.23 mg m-2 d-1
in the 40-year stand. Clearfelling affected environmental factors
and lead to higher daily soil temperatures during the summer
period, while it caused an increase in the soil water content and a
rise in the water table depth. Despite clearfelling, CO2 remained
the dominant greenhouse gas in terms of its greenhouse warming
potential. В© 2005 Elsevier Ltd. All rights reserved.
1409 Pan-European 13 C values of air and organic matter
from forest ecosystems
Hemming D., Yakir D., Ambus P. et al. Global Change Biology
2005 11/7 (1065-1093)
We present carbon stable isotope, 13 C, results from air and
organic matter samples collected during 98 individual field campaigns across a network of Carboeuroflux forest sites in 2001
(14 sites) and 2002 (16 sites). Using these data, we tested the
hypothesis that 13 C values derived from large-scale atmospheric
measurements and models, which are routinely used to partition
carbon fluxes between land and ocean, and potentially between
respiration and photosynthesis on land, are consistent with directly measured ecosystem-scale 13 C values. In this framework,
we also tested the potential of 13 C in canopy air and plant organic matter to record regional-scale ecophysiological patterns.
Our network estimates for the mean 13 C of ecosystem respired
CO2 and the related вЂ�discriminationвЂ™ of ecosystem respiration,
1.9вЂ° and 17.8 2.0вЂ°
er and
er respectively, were -25.6
in 2001 and -26.6
1.5вЂ° and 19.0
1.6вЂ° in 2002. The
results were in close agreement with 13 C values derived from
regional-scale atmospheric measurement programs for 2001, but
less so in 2002, which had an unusual precipitation pattern. This
suggests that regional-scale atmospheric sampling programs generally capture ecosystem 13 C signals over Europe, but may be
limited in capturing some of the interannual variations. In 2001,
but less so in 2002, there were discernable longitudinal and seasonal trends in er From west to east, across the network, there
was a general enrichment in 13 C ( 3вЂ° and
lвЂ° for the 2
years, respectively) consistent with increasing Gorczynski continentality index for warmer and drier conditions. In 2001 only,
seasonal 13 C enrichment between July and September, followed
by depletion in November (from about -26.0вЂ° to -24,5вЂ° to 30.0вЂ°), was also observed. In 2001, July and August er values
across the network were significantly related to average daytime
vapor pressure deficit (VPD), relative humidity (RH), and, to
a lesser degree, air temperature (Ta ), but not significantly with
monthly average precipitation (Pm ). In contrast, in 2002 (a much
wetter peak season), er was significantly related with Ta , but
not significantly with VPD and RH. The important role of plant
physiological processes on er in 2001 was emphasized by a
relatively rapid turnover (between 1 and 6 days) of assimilated
carbon inferred from time-lag analyses of er vs. meteorological
parameters. However, this was not evident in 2002. These
analyses also noted corresponding diurnal cycles of er and meteorological parameters in 2001, indicating a rapid transmission
of daytime meteorology, via physiological responses, to the er
signal during this season. Organic matter 13 C results showed
progressive 13 C enrichment from leaves, through stems and roots
to soil organic matter, which may be explained by 13 C fractionation during respiration. This enrichment was species dependent
and was prominent in angiosperms but not in gymnosperms. 13 C
values of organic matter of any of the plant components did not
well represent short-term er values during the seasonal cycle,
and could not be used to partition ecosystem respiration into
autotrophic and heterotrophic components. В© 2005 Blackwell
Publishing Ltd.
1410 Statistical analysis of the major variables controlling
methane emission from rice fields
Yan X., Yagi K., Akiyama H. and Akimoto H. Global Change
Biology 2005 11/7 (1131-1141)
Rice cultivation is an important anthropogenic source of atmospheric methane (CH4 ), the emission of which is affected by
management practices. Many field measurements have been
conducted in major rice-producing countries in Asia. We compiled a database of CH4 emissions from rice fields in Asia from
peer-reviewed journals. We developed a statistical model to relate CH4 flux in the rice-growing season to soil properties, water
regime in the rice-growing season, water status in the previous
season, organic amendment and climate. The statistical results
showed that all these variables significantly affected CH4 flux,
and explained 68% of the variability. Organic amendment and
water regime in the rice-growing season were the top two controlling variables; climate was the least critical variable. The
average CH4 fluxes from rice fields with single and multiple
drainages were 60% and 52% of that from continuously flooded
rice fields. The flux from fields that were flooded in the previous
season was 2.8 times that from fields previously drained for a
long season and 1.9 times that from fields previously drained for
a short season. In contrast to the previously reported optimum
soil pH of around neutrality, soils with pH of 5.0-5.5 gave the
maximum CH4 emission. The model results demonstrate that
application of rice straw at 6tha-1 before rice transplanting can
increase CH4 emission by 2.1 times; when applied in the previous
season, however, it increases CH4 emission by only 0.8 times.
Default emission factors and scaling factors for different water
regimes and organic amendments derived from this work can be
used to develop national or regional emission inventories. В©
2005 Blackwell Publishing Ltd.
1411 Soil CN ratio as a scalar parameter to predict nitrous
oxide emissions
Klemedtsson L., Von Arnold K., Weslien P. and Gundersen P.
Global Change Biology 2005 11/7 (1142-1147)
Forested histosols have been found in some cases to be major, and
in other cases minor, sources of the greenhouse gas nitrous oxide
LANDFORMS
(N2 O). In order to estimate the total national or global emissions
of N2 O from histosols, scaling or mapping parameters that can
separate low- and high-emitting sites are needed, and should be
included in soil databases. Based on interannual measurements
of N2 O emissions from drained forested histosols in Sweden, we
found a strong negative relationship between N 2 O emissions and
soil CN ratios (r2adj = 0.96, mean annual N2 O emission = (-bCNratio)
).
ae
The same equation could be used to estimate the N2 O emissions
from Finnish and German sites based on CN ratios in published
data. We envisage that the correlation between N2 O emissions
and CN ratios could be used to scale N2 O emissions from histosols determined at sampled sites to national levels. However,
at low CN ratios (i.e. below 15-20) other parameters such as
climate, pH and groundwater tables increase in importance as
regulating factors affecting N2 O emissions. В© 2005 Blackwell
Publishing Ltd.
LANDFORMS
Weathering and related landforms
1412 Climatic control on clay mineral formation: Evidence
from weathering profiles developed on either side of the Western Ghats
Deepthy R. and Balakrishnan S. Proceedings of the Indian
Academy of Sciences, Earth and Planetary Sciences 2005 114/5
(545-556)
Many physico-chemical variables like rock-type, climate, topography and exposure age affect weathering environments. In the
present study, an attempt is made to understand how the nature
of clay minerals formed due to weathering differs in tropical
regions receiving high and low rainfall. Clay mineralogy of
weathering profiles in west coast of India, which receives about
3 m rainfall through two monsoons and those from the inland
rain-shadow zones (< 200 cm rainfall) are studied using X-ray
diffraction technique. In the west coast, 1:1 clays (kaolinite)
and Fe-Al oxides (gibbsite/goethite) are dominant clay minerals
in the,weathering profiles while 2:1 clay minerals are absent
or found only in trace amounts. Weathering profiles in the rain
shadow region have more complex clay mineralogy and are dominated by 2:1 clays and kaolinite, Fe-Al oxides axe either less
or absent in clay fraction. The kaolinite-smectite interstratified
mineral in Banasandra profiles are formed due to transformation
of smectites to kaolinite, which is indicative of a humid paleoclimate. In tropical regions receiving high rainfall the clay mineral
assemblage remains the same irrespective of the parent rock
type. Rainfall and availability of water apart from temperature,
are the most important factors that determine kinetics of chemical weathering. Mineral alteration reactions proceed through
different pathways in water rich and water poor environments. В©
Printed in India.
Fluvial landforms
1413 Geomorphology and American dams: The scientific,
social, and economic context
Graf W.L. Geomorphology 2005 71/1-2 (3-26)
American geomorphologic research related to dams is embedded
in a complicated context of science, policy, economics, and culture. Research into the downstream effects of large dams has
progressed to the point of theory-building, but generalization and
theory-building are from this research because (1) it is highly focused on a few locations, (2) it concerns mostly very large dams
rather than a representative sample of sizes, (3) the available
record of effects is too short to inform us on long-term changes,
(4) the reversibility of changes imposed by dam installation and
operation is unknown, and (5) coordinated funding for the needed
research is scarce. In the scientific context, present research is
embedded in a history of geomorphology in government service,
with indistinct boundaries between "basic and applied" research.
The federal policy that most strongly influences present geomorphological investigations connected with dams is related to
267
habitat for endangered species, because the biological aspects of
ecosystems are directly dependent on the substrate formed by
the sediments and landforms that are influenced by dams. The
economic context for research includes large amounts of public
funds for river restoration, along with substantial private investments in dams; and geomorphology is central to these expensive
issues. The cultural context for research is highly contentious and
dominated by advocacy procedures that include intense scrutiny
of any geomorphologic research related to dams. Advocates are
likely to use the products of geomorphological research to make
cases for their own positions. В© 2005 Elsevier B.V. All rights
reserved.
1414 Dams and geomorphology: Research progress and
future directions
Petts G.E. and Gurnell A.M. Geomorphology 2005 71/1-2 (2747)
Dams impose changes of flow and sediment transfer that drive
changes of channel form along the downstream regulated river.
These changes have been described for more than 50 years but
process-form relationships have only been advanced with the
establishment of a conceptual framework during the 1970s, and
then the extension of monitoring data and advancement of remote sensing technologies, particularly over the past 20 years.
This paper reviews these developments and identifies three influential themes: (i) channel dynamics, (ii) the role of riparian
vegetation, and (iii) channel change as the driver of ecological
change. Changes can be rapid in semi-arid regions but elsewhere
relaxation periods may extend to millenia. In these latter cases
regime or steady-state models should be replaced by models of
transient states applied to the reach scale in order to respond to
the needs of river managers over decadal timescales. В© 2005
Elsevier B.V. All rights reserved.
1415 The geomorphic influences of beaver dams and failures
of beaver dams
Butler D.R. and Malanson G.P. Geomorphology 2005 71/1-2
(48-60)
Uncounted millions of beaver ponds and dams existed in North
America prior to European contact and colonization. These
ponds acted as sediment traps that contained tens to hundreds
of billions of cubic meters of sediment that would otherwise
have passed through the fluvial system. Removal of beavers by
overtrapping in the 16th-19th centuries severely reduced their
number and the number of ponds and dams. Dam removal altered the fluvial landscape of North America, inducing sediment
evacuation and entrenchment in concert with widespread reduction in the wetlands environments. Partial recovery of beaver
populations in the 20th century has allowed reoccupation of the
entirety of the pre-contact range, but at densities of only onetenth the numbers. Nevertheless, modern beaver ponds also trap
large volumes of sediment in the high hundred millions to low
billions of cubic meters range. Failure of beaver dams is a more
common phenomenon than often as sumed in the literature. During the past 20 years, numerous cases of dam failure have been
documented that resulted in outburst floods. These floods have
been responsible for 13 deaths and numerous injuries, including
significant impacts on railway lines. В© 2005 Elsevier B.V. All
rights reserved.
1416 Effects of Jackson Lake Dam on the Snake River and
its floodplain, Grand Teton National Park, Wyoming, USA
Marston R.A., Mills J.D., Wrazien D.R. et al. Geomorphology
2005 71/1-2 (79-98)
In 1906, the Bureau of Reclamation created Jackson Lake Dam
on the Snake River in what later became Grand Teton National
Park. The geomorphic, hydrologic and vegetation adjustments
downstream of the dam have yet to be documented. After a
larger reservoir was completed further downstream in 1957, the
reservoir release schedule from Jackson Lake Dam was changed
in a manner that lowered the magnitude and frequency of floods.
The stability of the Snake River exhibited a complex response to
the change in flow regime. Close to major tributaries, the Snake
River increased in total sinuosity and rates of lateral channel
migration. Away from the influence of tributaries, the river experienced fewer avulsions and a decrease in sinuosity. Vegetation
268
LANDFORMS
maps were constructed from 1945 and 1989 aerial photography and field surveys. Using these data, we determined how
vegetation is directly related to the number of years since each
portion of the floodplain was last occupied by the channel. The
vegetation has changed from a flood-pulse dominated mosaic
to a more terrestrial-like pattern of succession. Changes in the
Snake River and its floodplain have direct implications on bald
eagle habitat, moose habitat, fish habitat, safety of rafting and
canoeing, and biodiversity at the community and species levels.
В© 2005 Elsevier B.V. All rights reserved.
1417 Floodplain-river ecosystems: Fragmentation and water resources development
Thoms M.C., Southwell M. and McGinness H.M. Geomorphology 2005 71/1-2 (126-138)
Floodplain-river ecosystems are natural fragmented systems because of periodic hydrological connections. The integrity of
these ecosystems is thought to be dependent, in part, upon exchanges of energy and matter between patches, such as the main
river channel, adjacent floodplain surface and other morphological features, during periods of connection. Flow regulation
and its associated infrastructure change the natural character of
fragmentation in floodplain-river ecosystems, and have important
consequences for their overall productivity. This paper considers
the influence of water resources development on the character of
fragmentation in a large lowland river in SE Australia. Largescale water resources development in the Macintyre River, Australia, has significantly altered the spatial and temporal patterns
of hydrological connections. The construction of weirs and other
embankments on the lower Macintyre River floodplain prevents
water movement through a series of anabranch channels thereby
reducing the availability of these floodplain patches by 55%. In
addition, because of flow regulation, hydrological connections to
these channels occur up to 22% less often. Data are presented
showing the impacts of these changes on the potential supply
of dissolved organic carbon from the anabranch channels during
periods of inundation over a 98-year period. Reductions of up
to 98% of potential dissolved organic carbon supply from some
anabranch channels were noted. В© 2005 Elsevier B.V. All rights
reserved.
1418 Statistical analysis of lateral migration of the Rio
Grande, New Mexico
Richard G.A., Julien P.Y. and Baird D.C. Geomorphology 2005
71/1-2 (139-155)
The lateral migration rates of alluvial rivers are affected by
changes in water and sediment regimes. The Rio Grande downstream from Cochiti Dam exhibits spatial and temporal variability
in lateral movement rates documented since 1918. A tremendous database exists that documents planform, bed material size,
channel geometry, and water and sediment regimes. A statistical
analysis reveals that migration rates primarily decreased with
decreasing flow energy (R2 > 0.50, p < 0.0001). The addition
of a second parameter describing total channel width increased
the explained variance to > 60%. The findings show that lateral
movement increases with increasing flow energy and with degree
of braiding. В© 2005 Elsevier B.V. All rights reserved.
1419 Equilibrium or indeterminate? Where sediment
budgets fail: Sediment mass balance and adjustment of
channel form, Green River downstream from Flaming Gorge
Dam, Utah and Colorado
Grams P.E. and Schmidt J.C. Geomorphology 2005 71/1-2 (156181)
This study examines bed and bank adjustment in the 105-km
reach of the Green River immediately downstream from Flaming Gorge Dam by the use of historical aerial and oblique
photographs, analysis of current and abandoned stream-gaging
records, and field observations. Although this segment has been
previously characterized as sediment deficient, these data show
that sediment is accumulating in all reaches and that the bed has
not degraded at any location where historical data are available.
Adjustment is occurring through a combination of deposition of
post-dam sediment and stabilization of pre-dam deposits, resulting in a 10-30% reduction in average width of the channel. All
post-dam surfaces are colonized by woody riparian vegetation.
The style of channel adjustment varies between geomorphically
defined reaches. In canyons dominated by debris fans and gravelbedded restricted meandering reaches, gravel bars have become
inactive and accumulated fine sediment. In the sand-bedded
meandering reaches, existing islands have increased in size and
new mid-channel islands have formed. In all of these types of
reaches, post-dam deposits line the banks and sediment has accumulated in side-channels that previously separated islands from
the bank. These findings demonstrate that sediment budgets that
show a balance between inputs and outputs cannot necessarily
be interpreted to indicate channel equilibrium. A sediment mass
balance for 150-km reach between the dam and the first long-term
gage indicates approximate balance of inputs and outputs for the
pre- and post-dam periods. When uncertainty in budget components is considered, the mass balance is indeterminate. Although
the Green River may have been in approximate equilibrium in the
pre-dam period, we have shown that channel width is decreasing
in the post-dam period. The post-dam deposits constitute a small
but a significant component of the sediment budget upstream
from the first major tributary. Sediment is supplied to this reach
by small tributaries and, to a lesser extent, erosion of pre-dam
alluvium. Downstream from the study area, the volume of the
post-dam deposits is tiny relative to the volume of sediment input
from the first major tributary. В© 2005 Elsevier B.V. All rights
reserved.
1420 Potential sedimentation impacts related to dam removal: Icicle Creek, Washington, U.S.A
Lorang M.S. and Aggett G. Geomorphology 2005 71/1-2 (182201)
A series of small dams were built in Icicle Creek in 1937 to
facilitate the operations of Leavenworth National Fish Hatchery.
However, several of those dams have been abandoned spurring
recent discussions among local watershed conservation groups,
as well as state and federal agencies, about removing the dams
and the potential impact to the lower reaches of Icicle Creek due
to elevated sedimentation. The objective of this study was to
measure the total volume of sediment trapped behind the Icicle
Creek dams and estimate the potential sedimentation impacts for
the lower portion of Icicle Creek should the dams be removed.
Another objective was to assess the ability of the river to flush
the sediments and naturally restore the system to as close to
its predam condition as possible. A flow-competence approach
was used to assess the restoration potential of the river to do the
work of flushing sediments and reestablishing the predam stream
channel characteristics. A sediment probe, a total station, a GPS
and aerial photographs were used to map out sediment deposits
and measure their depths to determine sediment volumes. Grain
size distributions from bed sediments, bars, islands and stream
banks were used to assess potential downstream sedimentation
impacts. The total volume of sediment trapped behind the dams
was estimated at 36,000 m3 ( 4000 m3 ). The river has sufficient
stream power to flush these sediments over 90% of its natural
discharge regime. Controlled flushing of the trapped sediments
over several years poses very little threat to the water quality and
spawning habitats in the lower Icicle Creek scaled against natural
flux rates. В© 2005 Elsevier B.V. All rights reserved.
1421 The evolution of gravel bed channels after dam removal: Case study of the Anaconda and Union City Dam
removals
Wildman L.A.S. and MacBroom J.G. Geomorphology 2005 71/12 (245-262)
The Anaconda and Union City Dams on the Naugatuck River
in Connecticut were removed in February and October 1999.
A detailed study of the sites prior to removal was undertaken
including sediment testing and predictions of upstream channel
formation post-dam removal. The 3.35-m-high timber crib/rock
fill spillway of the Anaconda Dam partially breached during a
storm prior to the damвЂ™s scheduled removal allowing a portion
of the impounded sediment to move down through the river system. This event changed the removal plans and the remainder
of the spillway was removed under an emergency order in the
course of 4 days. The Union City Dam, a 2.44-m-high timber
crib/rock fill dam capped with concrete and stone, was removed
on schedule. A portion of the impounded sediment was removed
by mechanical means during the deconstruction of the structure.
LANDFORMS
The evolution of the two upstream channels post-project provided unique challenges and valuable insights as to what kind of
channel transition can be expected in gravel bed river systems
after a low head dam has been removed. This paper describes the
initial engineering analysis and design, the subsequent removal
of the two dams, and compares observations on the transition of
the upstream channels following dam removal to the initial engineering predictions and other models. The relatively steep gravel
bed channels evolved in a predictable manner, except where anthropogenic barriers (sanitary sewer, rock weir) interrupted. В©
2005 Elsevier B.V. All rights reserved.
1422 Riverine landscape and geomorphology: Ecological
implications and river management strategy
LehotskВґy M. and GreЛ‡skovВґa A. Ekologia Bratislava 2004
23/SUPPL. 1 (179-190)
Traditionally, geographers and landscape ecologists have focused
their attention on terrestrial systems (in Slovakia LANDEP, landscape potencial approach are examples) and rivers have been
considered either as elements of landscape pattern as biocorridors or as units that are linked to the terrestrial landscape by
flows across boundaries. We present the methodology of riverine
landscape with accent to its geomorphic base. The concept of
river connectivity and river continuum, hierarchy, flood-pulse
and related telescoping concepts as well as channel sensitivity
and natural capital value concepts are discussed.
1423 Case study: Modeling the lateral mobility of the Rio
Grande below Cochiti dam, New Mexico
Richard G.A., Julien P.Y. and Baird D.C. Journal of Hydraulic
Engineering 2005 131/11 (931-941)
The Cochiti reach of the Rio Grande served as a case study to
test the hypothesis that the lateral mobility of an alluvial river decreases as the river approaches equilibrium. The lateral mobility
of the river was measured using a geographic information system from digitized aerial photographs of the nonvegetated active
channel between 1918 and 2001. Reach-averaged lateral mobility was quantified in terms of width change, lateral migration,
and total lateral movement. By 2001, the width of the Cochiti
Reach was close to the expected equilibrium width indicating that
the river had adjusted to the incoming water and sediment load.
An exponential equation based on deviation from equilibrium
width described 95-96% of the variance in channel width, 7890% of variance in migration rates, and 92% of the variance in
total lateral movement between 1918 and 1992. For validation
of the model, the 2001 width and migration rates were predicted
with errors as low as 19 and 8%, respectively. The exponential
width model was also appliedto four other rivers that exhibited
narrowing trends following dam construction and explained 8289% of the variance in width change on those rivers. Journal of
Hydraulic Engineering В© ASCE.
1424 Regional patterns of salt lake morphology in the lower
Yarra Yarra drainage system of Western Australia
Boggs D.A., Boggs G.S., Eliot I. and Knott B. Journal of Arid
Environments 2006 64/1 (97-115)
This paper examines the spatial variation of salt lake morphology
in the lower Yarra Yarra drainage system of Western Australia.
Shape, size (length and area), orientation and density of 4500
salt lakes were measured. Two main morphological groups were
distinguished: small (<10 ha), elliptical to circular playas with
a NNW-SSE orientation; and large (>30 ha), elongated playas.
Intra-system variability in morphologic characteristics was notable. Regional patterns in lake size, shape and density distribution were markedly different between the west and east sides
of the system. The boundary between the two sides coincides
approximately with rainfall distribution. The Morawa sub-division in the west of the region was morphologically different
from the remainder of the lower lacustrine system in that it had
a predominance of small, elliptical playas and lacked a major
playa. It was postulated that lake segmentation processes have
been enhanced in this part of the system through a combination
of local climate variation, the near-parallel orientation of the
thalweg of the drainage system axis relative to prevailing winds,
with possible topographical relief and geological influences. В©
2005 Elsevier Ltd. All rights reserved.
269
1425 The Oxaya anticline (northern Chile): A buckle enhanced by river incision?
Zeilinger G., Schlunegger F. and Simpson G. Terra Nova 2005
17/4 (368-375)
A prominent structure in the Western Escarpment of the Andes
of northern Chile is the Oxaya anticline, dissected at the culmination by >1500 m deep valleys. The distribution of fault
and fold structures indicates that the anticline could represent a
simple buckle. Buckling thus appears to have accommodated
crustal shortening in the plate overriding the subducting plate,
between the trench and the Western Cordillera. Cross-cutting
relationships between structures and dated strata indicated that
the time interval of enhanced buckling coincides with the period
when rates of valley formation were enhanced. We thus propose
that the formation of this anticline was enhanced by fluvial incision, which is consistent with the results of published theoretical
models. В© 2005 Blackwell Publishing Ltd.
1426 Recession rates of waterfalls in and upstream of the
Tateno canyon, Aso volcano (Japanese)
Hayakawa Y.S.,
Yokoyama S. and Matsukura Y.
Chikei/Transactions, Japanese Geomorphological Union
2005 26/4 (439-449)
Recession rates of two waterfalls, Ayugaeri Falls and Sugaru
Falls, which are associated with the gorge formation of in the
Tateno Canyon in the western part of the Aso caldera, are examined on the basis of the empirical equation after Hayakawa
and Matsukura (2003). The waterfalls are postulated to have
originated at a location out of the caldera as a waterfall which
was formed around the front of the Akase lava erupted from the
inside of the caldera. The initial waterfall receded about 2.8 km
upstream forming the gorge to the present site of the confluence
of the Shirakawa River and the Kurokawa River in the caldera.
At the confluence, the waterfall bifurcated into two waterfalls
which continued recession along the Shirakawa River and the
Kurokawa River to the present locations of the Ayugaeri and
Sugaru falls. The recession rates estimated from the equation are
0.086 m/y for Ayugaeri Falls and 0. 143 m/y for Sugaru Falls.
The calculated time taken for the recession from the confluence
to the present sites of the individual waterfalls is nearly equal: ca.
13,000 y, indicating that the bifurcation of the waterfalls occurred
about 13,000 years ago. Rough estimation suggests that the time
for the initial waterfall to recede the distance of 2.8 km is 14,00028,000 y, The total time of the waterfall recession from the start to
the present location is thus 27,000-41,000 y, which is consistent
with the age of the Akase lava flow (ca. 30,000 y).
1427 Gandak fan - A macro quaternary feature of middle
Ganga plain, Uttar Pradesh and Bihar
Prasad S. and Khan E.A. Journal of the Geological Society of
India 2005 65/5 (597-608)
Gandak fan, is a large lobate feature trending in NW-SE direction,
restricted between the fluvial regimes of Little Gandak in the west
and Burhi Gandak in the east, in parts of eastern Uttar Pradesh
and north Bihar. It is characterised by distinct geomorphology,
manifested by clusters of tals, palaeochannels, oxbow lakes and
spill over channels left out by a past history of river migration
and flash floods of Gandak and its predecessors. The terrain
is characterised by wide spread drapes of newer alluvium sediments locally known as Bhat Alluvium forming a calcareous,
fine sandy to silty soil. Granulometric properties of the sand
sequence associated with this unit indicate dominance of very
fine grained sand with median value of 3.0 phi. The clay mineral
study of this soil unit indicates preponderance of calcite mineral
(30%) besides illite, chlorite and muscovite. Based on the analysis and synthesis of data, an attempt has been made to interpret
the morphology of Gandak fan and the genesis of widespread
occurrences of Bhat Alluvium of this region. The model envisaged for the formation of the fan dwells on possible cataclasmic
neotectonic events related to Gandak Tear and other structures in
the vicinity. The neotectonic event triggered widespread river
migration/avulsion and cascades of mud flows released from
breach and spill over of some large lacustrine bodies formed
earlier by damming of the river course in the Jhawani Valley in
upstream of Gandak catchment area in Nepal. In addition, the
geological and geomorphological set up of Gandak Fan has also
270
LANDFORMS
relevance to environmental scenario of the area especially to the
perpetual floods in large tracts of north Bihar. It is also surmised
th at the cascades of mudflows related in the formation of fan
and rampant floods in the area might be the causative factors for
burial of many important temples and monasteries of Buddhist
period, such as Kushinagar, Vaishali, Lauria, etc. В© Geol. Soc.
India.
Coastal landforms
1428 Phytolith assemblages as indicators of coastal environmental changes and hurricane overwash deposition
Lu H.- Y. and Liu K.- B. Holocene 2005 15/7 (965-972)
We demonstrate that phytolith assemblages are a useful proxy for
reconstructing coastal environmental changes and for validating
the overwash origin of sand layers in palaeotempestology studies. Phytolith analysis was conducted on 50 topsoil or surface
sediment samples collected from a variety of coastal plant communities or depositional environments in the southeastern USA.
The data suggest that different coastal subenvironments can be
distinguished by their modern phytolith assemblages. For example, coastal marsh samples contain a diverse phytolith assemblage dominated by smooth-elongate and square morpho-types
and maritime forest samples are dominated by phytoliths from
palms and broadleaf dicotyledonous plants. Remarkably, the
phytolith assemblages from sand dunes are characterized by high
percentages of two-horned-tower, flat-tower, spool/horned-tower
and short-saddle types. Phytolith analysis of three prehistoric
sand layers in a sediment core from Western Lake, northwestern
Florida, shows that they contain a phytolith assemblage similar
to those characteristic of sand dunes and interdune meadows.
These observations are confirmed by the results of principal
components analysis and discriminant analysis on the modern
and fossil phytolith data sets. Our study results support the
interpretation that the sand layers in Western Lake were indeed
formed by the erosion of sand dunes during overwash processes
caused by landfalling catastrophic hurricanes. В© 2005 Edward
Arnold (Publishers) Ltd.
1429 Persistence of storm-induced morphology on a modal
low-energy beach: A case study from NW-Iberian Peninsula
Costas S., Alejo I., Vila- Concejo A. and Nombela M.A. Marine
Geology 2005 224/1-4 (43-56)
The morphology of low-energy beaches is inherited from highenergy events showing a non equilibrium state with the prevailing
conditions. An example of a sheltered, low-energy beach (Rodas
Beach, NW-Iberian Peninsula) is examined in this paper. The
evolution of six beach profiles was analysed during three years in
order to investigate the response of this beach under fair-weather
and storm conditions. The beach presented significant morphological differences alongshore due to its geographical location
with respect to the wave approach. These differences determined
the sediment transfer pattern (longshore or cross-shore sediment
transport) from the emerged beach towards the adjacent inner
shoreface zone. Significant morphological changes at each profile seem to be related to the incidence of sea waves along the
beach superimposed on persistent swell during winter. Morphological changes were recorded under high-energy storms, during
winter, whereas the recovery to prestorm conditions occurred
under prevailing fair weather conditions, during summer. The
traditional beach classification parameter Relative Tidal Range
(RTR), which takes into account the effect of the tide range, was
found unsuitable to properly classify such a mesotidal low-energy beach. Therefore, a new parameter, the Relative Tidal Range
Maximum (RTRmax) was introduced, which is a modification of
the commonly used RTR. RTRmax uses the highest wave breaking
height, observed during high-energy storm conditions, instead of
the modal wave breaking height. By using this parameter, the
studied beach could be properly classified into the traditional
beach classification models taking into account the tide range.
Since low-energy beaches generally show a morphology that
is inherited from higher energy conditions than the prevailing
conditions, it is expected that the RTRmax will be applicable for
the classification of other low-energy sheltered beaches. В© 2005
Elsevier B.V. All rights reserved.
1430 Barrier formation on an actively prograding delta system: The Red River Delta, Vietnam
Van Maren D.S. Marine Geology 2005 224/1-4 (123-143)
An extensive barrier-spit system 20 to 30 km long developed on
the delta front platform of the Ba lat Delta within a relatively short
period (10-20 years). However, it was not evident whether the
formation was related to river floods, typhoons or calm weather
conditions, or to cross-shore or alongshore sediment transport
mechanisms. Therefore a process-based numerical model that
simulates sediment transport and morphologic changes by waves,
tides, wind, and river flow, is used to analyze the processes that
govern this barrier formation. The mechanism that initiates the
barrier formation is concluded to be onshore transport by wave
asymmetry of sediment previously transported seaward in the
buoyant river plume. The main mechanism that counteracts the
barrier formation is probably destruction of the barrier by river
flow. During the subsequent transformation from a subaqueous barrier into a sub-aerial barrier-spit system, overwashes and
alongshore sediment transport become increasingly important.
This spit system therefore appears to be dominated by alongshore
processes, even though its initial formation is more strongly regulated by cross-shore processes. The importance of cross-shore
processes results in a minor contribution of typhoons to the initial
formation of these barriers. Typhoons are not very important to
destruction of barriers as well, because wave energy is gradually
dissipated over the gentle offshore profile, which in turn results
from river plume sedimentation. В© 2005 Elsevier B.V. All rights
reserved.
1431 Fetch limited barrier islands of Chesapeake Bay and
Delaware Bay
Lewis D.A., Cooper J.A.G. and Pilkey O.H. Southeastern Geology 2005 44/1 (1-17)
Barrier islands within bays, lagoons, estuaries and other protected
waters have never been the subject of systematic research on a
large scale. Within both the Chesapeake and Delaware Bays,
barrier islands are numerous and widely distributed. Totaling
more than 300 in number, these fetch limited barrier islands
exhibit a range of morphologies uncommon along open ocean
shorelines. We group the barrier islands in the two bays into
three primary categories based on their morphology and location.
In general, they are much shorter ( km), narrower (<25m), and
lower (1-2m) than their open ocean analogs, yet they behave in
much the same way in their response to oceanographic processes.
The greatest difference between ocean and bay barriers is the
strong control of evolutionary processes by vegetation, usually
salt marsh, in the bays.
1432 The impact of Hurricane Georges (September 28,
1998) across Dauphin Island, Alabama
Froede Jr. C.R. Southeastern Geology 2005 44/1 (45-51)
On the morning of September 28, 1998, Hurricane Georges (a
Category 2 hurricane on the Saffir-Simpson scale) made landfall
between the towns of Ocean Springs and Biloxi, Mississippi.
Passing well to the west of Dauphin Island, the storm still impacted the island with wind speeds up to 129 km/hr (a Category
1 hurricane on the Saffir-Simpson scale). This resulted in substantial changes along the islandвЂ™s gulf side. The eastern end of
the island experienced a storm surge along with accompanying
storm waves that easily overtopped the swash zone berm crest.
Storm waves washed tens of meters landward and flattened the
beach profile. Much of the western end of the island was completely overwashed by storm waves. As of early 2005, natural
shoreline processes have not restored the pre-storm beach profile
or returned the swash zone to its former position. Tropical storms
and hurricanes that impact the island reveal its vulnerability and
dependence on regular sand nourishment. Hurricane Georges
exposed the fragile nature and precarious setting of Dauphin
Island in the Gulf of Mexico.
LANDFORMS
1433 Contribution of simulations on historical bathymetries
to the understanding of evolutions of estuarine sand banks
(French) (Apports de la modВґelisation sur bathymВґetries historiques dans la comprВґehension des eВґ volutions des bancs de sable
estuariens)
Bertin X. and Chaumillon E. Comptes Rendus - Geoscience 2005
337/15 (1375-1383)
Formation and evolution of estuarine sand ridges are some of the
less well known among the different classes of sand banks. Simulation of tides and related sand bedload transport on historical
bathymetries brings new insights about the secular evolution of
two estuarine sand ridges (the Saint-Georges and the вЂ�Longe de
BoyardвЂ™ sand banks, Atlantic coast of France). Two different
mechanisms are involved in order to explain the evolutions of
these banks, suggesting the category of estuarine sand banks to
be less homogenous than it is proposed in the last classifications
of sand banks. В© 2005 AcadВґemie des sciences. PubliВґe par
Elservier SAS. Tous droits rВґeservВґes.
Arid landforms
1434 Preliminary assessment of sand dune stability along
a bioclimatic gradient, North-Central and Northwestern
Oklahoma
Cordova C.E., Porter J.C., Lepper K. et al. Great Plains Research
2005 15/2 (227-249)
Sandhills of eolian origin and currently active dunes in Oklahoma
are located mainly on the northern side of the main rivers. Their
longitudinal distribution spans a gradient of annual precipitation
ranging from 914 mm in the east to 403 mm in the west. Vegetation types along this gradient include cross-timbers woodlands
in the east and sand-sage and short grasses in the west. The
information presented here is a preliminary assessment of sand
dune dynamics and morphology, soils, and vegetation as the
basis for an ongoing study on past and present processes of sand
dune stability. For this purpose, six areas along the east-west
precipitation gradient were selected to evaluate potential sources
of information. Pedostratigraphic data were used to reconstruct
prehistoric landscape-change events and sequential aerial photographs were used to reconstruct modern processes affecting
sand dune stability in the context of climate change and human
agency. В© Copyright by the Center for Great Plains Studies,
University of Nebraska-Lincoln.
1435 Aeolian sand depositional records from Western Nebraska: Landscape response to droughts in the past 1500
years
Forman S.L., Marn L., Pierson J. et al. Holocene 2005 15/7
(973-981)
The Great Plains is dominated by presently stabilized dune fields
that are indicators of extreme drought in the late Holocene. This
study focused on deciphering the timing of reactivation of dunes
in western Nebraska. Stratigraphy adjacent to dune-dammed
lakes reveals aeolian sand separated by palaeosols, indicating
mobilization of aeolian sand followed by landscape stability. The
chronology of aeolian-sand depositional events is constrained using the luminescence-based, single aliquot regeneration method,
providing resolution to relate dune movement to tree-ring and
palaeolimnologic records of drought. There are at least a six
aeolian depositional events in the past 1500 years, with apparent
mean ages of 1390 130, 670 70, 470 40, 240 40, 140
20 and 70 10 yr. All study sites show evidence for aeolian accumulation in the twentieth century, potentially reflecting
the 1930s drought. Significant aeolian activity is coincident
with the tree-ring-identified sixteenth-century megadrought, indicating widespread landscape impacts. В© 2005 Edward Arnold
(Publishers) Ltd.
1436 Late Pleistocene eolian history of the Liwa region,
Arabian Peninsula
Stokes S. and Bray H.E. Bulletin of the Geological Society of
America 2005 117/11-12 (1466-1480)
The Liwa region of the United Arab Emirates is one of the most
distinctive geomorphological features of the Rub Al Khali desert
of southern Arabia. Characterized by a sharp crescentic boundary
271
coincident with a N-S elevation drop of 65 m with the transverse
ridges in Al QЛ†afa to the north, Liwa is an area of some of the
worldвЂ™s largest megabarchan dunes. Deep drilling of continuous
cores has provided an opportunity to observe the internal structure
and age of these two ergs. Subsurface stratigraphy is complex,
reflecting rapid facies transitions between dune and interdune
sub-environments. Most of the cored sediment is dominated
by cross-bedded and structureless sand units of inferred eolian
(transverse dune) depositional origin. A total of 56 optical ages
for sand-sized quartz grains extracted from these cores provide
a chronological framework for deposition of the late Quaternary
ergs. A marine isotope stage (MIS) 5 erg is identified north of
the Liwa crescent in the Al QЛ†afa region, which reaches vertical
thicknesses >100 m. A MIS 1 erg in the form of megabarchan
dunes is recorded south of the Liwa crescent. This was deposited
on a pre-MIS 5 land surface, since ca. 6 ka, over a period of just
a few thousand years. Contemporary bypassing of eolian sands
via superimposed dunes in both Al QЛ†afa and Liwa appears to be
in equilibrium with the current wind regime. A consideration of
a variety of factors that control the availability, mobilization, and
preservation of eolian sediments and resulting bedforms leads us
to infer that the system is not sediment-supply or transport limited. Instead, the system is preservation limited, being controlled
by a correlated combination of sea level and precipitation. Both
of these factors are strongly linked to global climate variations in
the eccentricity (ca. 100 ka) band. Paradoxically, the bulk of the
preserved record of eolian activity in the southern Arabian Peninsula occurs within relatively humid interglacial phases rather
than arid intervals. Evidence of eolian deposition during arid
phases may not for the most part be preserved in large areas of
the sand sea. Observed contrasts in the preserved record of eolian
activity between Al QЛ†afa and Liwa, and the Wahiba Sand Sea,
may in part relate to contrasting eolian bedform morphology. В©
2005 Geological Society of America.
Regional physiography
1437 Palaeo-environment reconstruction from the geomorphological context of four archaeological sites on the East-Lyonnais plain (RhЛ†one, France) (French) (Reconstitution palВґeoenvironnementale a` partir du contexte gВґeomorphologique de
quatre sites archВґeologiques de la plaine de lвЂ™est Lyonnais
(RhЛ†one, France))
Franc O. Quaternaire 2005 16/2 (95-105)
The East-Lyonnais plain, where glaciers have spread debris to
form either morainic hills covered with loess or fluvioglacial
terraces, has been inhabited by Man from the Mesolithic period
to Antiquity. On the hills, where we can see some undulations,
an interesting stratigraphy is developed with pedogenesis, colluviums and anthropological impact on the environment. The
signatures of these processes are analysed by means of sedimentologic and micromorphologic surveys, methods used as arguments to intepret this kind of stratigraphy. A palaeo-environment
reconstruction, supported by radio-carbon and archaelogical dating, is thus proposed for four sites on two of the morainic hills.
In conclusion, the thickness of the endorheic depression infill, at
different periods, seems to depend on man-made pressure rather
than climatic considerations.
1438
Geomorphological and geological studies for
Bangladesh: A review (Japanese)
Takagi T., Oguchi T., Zaiki M. and Matsumoto J.
Chikei/Transactions, Japanese Geomorphological Union 2005
26/4 (405-422)
Rapid geomorphological changes mainly due to fluvial processes
have been uccurring in Bangladesh despite its very flat topography. This observation reflects its location in the downstream
areas of the two large rivers: Ganges and Brahmaputra, with their
upstream areas being subjected to abundant rainfall. Fluvial systems in Bangladesh are quite complex, because the meandering
Ganges and the braided Brahmaputra merges in the center of the
country, and southern plains are prone to tide-related processes.
Despite such interesting geomorphological settings, detailed scientific studies on landforms and sediments in Bangladesh have
272
LANDFORMS
only been activated since the 1990s, because of political chaos in
the earlier decades and a limited number of researchers within the
country. It is necessary to extend recent studies to better understand the geomorphology of the country. This paper reviews the
history and contents of geomorphological and geological studies
for Bangladesh, to facilitate future progress of relevant research.
Although this paper intends to cover a wide range of topics, special attention is directed toward fluvial geomorphology in relation
to frequent large floods, which significantly affect peopleвЂ™s life
in Bangladesh.
Neotectonics and structural control
1439 Late Quaternary systematic stream offsets caused by
repeated large seismic events along the Kunlun fault, northern Tibet
Fu B., Awata Y., Du J. and He W. Geomorphology 2005 71/3-4
(278-292)
The Kunlun fault is one of the largest strike-slip faults in northern
Tibet, China. In this paper, we focus upon the Kusai LakeKunlun Pass segment of the fault to understand the geomorphic
development of offset streams caused by repeated large seismic
events, based on tectono-geomorphic analysis of high-resolution
satellite remote sensing images combined with field studies. The
results indicate that systematic left-lateral stream offsets appear
at various scales across the fault zone: Lateral offsets of small
gullies caused by the 2001 Mw 7.8 Kunlun earthquake vary typically from 3 m to 6 m, meanwhile streams with cumulative
offsets of 10 m, 25-30 m, 50-70 m, 250-300 m and 750-1400 m
have resulted from repeated large seismic events during the late
Quaternary. An average slip rate of 10 1 mm/year has been
estimated from the lateral stream offsets and 14 C ages of alluvial
fan surfaces incised by the streams. A three-dimensional model
showing tectono-geomorphic features along a left-lateral strikeslip fault is also presented. The Kusai Lake-Kunlun Pass segment
provides an opportunity to understand the relationship between
geomorphic features produced by individual large seismic events
and long-term geomorphic development caused by repeated large
seismic events along a major strike-slip fault. В© 2005 Elsevier
B.V. All rights reserved.
1440 Regional relief characteristics and denudation pattern
of the western Southern Alps, New Zealand
Korup O., Schmidt J. and McSaveney M.J. Geomorphology 2005
71/3-4 (402-423)
The Southern Alps of New Zealand are the topographic expression of active oblique continental convergence of the Australian
and Pacific plates. Despite inferred high rates of tectonic and
climatic forcing, the pattern of differential uplift and erosion remains uncertain. We use a 25-m DEM to conduct a regional-scale
relief analysis of a 250-km long strip of the western Southern
Alps (WSA). We present a preliminary map of regional erosion and denudation by overlaying mean basin relief, a modelled stream-power erosion index, river incision rates, historic
landslide denudation rates, and landslide density. The interplay
between strong tectonic and climatic forcing has led to relief
production that locally attains 2 km in major catchments, with
mean values of 0.65-0.68 km. Interpolation between elevations
of major catchment divides indicates potential removal of l01 103 km3 , or a mean basin relief of 0.51-0.85 km in the larger
catchments. Local relief and inferred river incision rates into
bedrock are highest about 50-67% of the distance between the
Alpine fault and the main divide. The mean regional relief variability is
0.5 km. Local relief, valley cross-sectional area,
and catchment width correlate moderately with catchment area,
and also reach maximum values between the range front and
the divide. Hypsometric integrals show scale dependence, and
together with hypsometric curves, are insufficient to clearly differentiate between glacial and fluvial dominated basins. Mean
slope angle in the WSA ( = 30В°) is lower where major longitudinal valleys and extensive ice cover occur, and may be an
insensitive measure of regional relief. Modal slope angle is strikingly uniform throughout the WSA ( = 38-40В°), and may record
adjustment to runoff and landsliding. Both and show non-linear relationships with elevation, which we attribute to dominant
geomorphic process domains, such as fluvial processes in lowaltitude valley trains, surface runoff and frequent landsliding on
montane hillslopes, "relief dampening" by glaciers, and rock
fall/avalanching on steep main-divide slopes. В© 2005 Elsevier
B.V. All rights reserved.
1441 Magmatic and tectonic history of IcelandвЂ™s western rift
zone at Lake Thingvallavatn
Bull J.M., Minshull T.A., Mitchell N.C. et al. Bulletin of the
Geological Society of America 2005 117/11-12 (1451-1465)
High rates of Holocene sedimentation in a lake spanning the
Thingvellir rift zone of western Iceland provide an unusual opportunity to study the interaction of tectonic and magmatic processes on time scales of thousands of years. Lake Thingvallavatn
is oriented SW-NE, parallel to the trend of normal faults and fissures, which extend northeast from Hengill, a central volcano
system. ThingvallavatnвЂ™s lake sediments provide a continuous
high-fidelity record of tectono-magmatic processes. Chirp subbottom profiler and sidescan records, together with sediment core
information, enabled us to improve constraints on lake stratigraphy since the emplacement of a postglacial lava at 9.1 0.3
ka. This lava, together with three younger horizons, enabled
detailed study of the main tectonic and magmatic events. A
major Hengill volcanic event, which controlled the development
of the present-day lake morphology, occurred at 1.9 ka, with the
eruption of a scoria cone within the lake (Sandey). During this
event, the Nesjahraun lava was erupted into the southern part of
the lake, the Sandey scoria cone was formed, and major faulting
and subsidence occurred in the northern part of the lake, resulting
in the formation of an asymmetrical rift. Within the southern part
of the lake, a deformed sequence of sediments aged 2.9-1.5 ka,
between undeformed younger and older sediments, indicates that
liquefaction phenomena are associated with the emplacement of
the Nesjahraun lava. Analysis of fault displacement reveals that
the total throw summed over all faults across the width of the
rift zone is approximately constant (110-130 m) along the long
axis of the rift. We estimate an extension rate on the faults of
3.3-8.2 mm yr-1 since 9.1 ka, assuming fault dips of 60-75В°,
which represents 17%-43% of the total plate boundary extension
estimated from global plate motion inversion. We speculate that
the remaining extension must either be taken up elsewhere in
Iceland, for example in the eastern rift zone or along the South
Iceland seismic zone, or that extension estimated over the last
9 k.y. underestimates the long-term extension rate due to incomplete sampling of the episodic magmatic component. В© 2005
Geological Society of America.
1442 Recognition of past earthquakes along the Sparta fault
(Peloponnesus, southern Greece) during the Holocene, by
combining results of different dating techniques
Papanastassiou D., Gaki- Papanastassiou K. and Maroukian H.
Journal of Geodynamics 2005 40/2-3 (189-199)
Sparta fault is an impressive landform, located on the eastern
front of Taygetos mountain, southern Greece. Detailed morphotectonic observations on this fault suggest that it should be
active at least since Early Quaternary. However, according to
the current seismological knowledge, this region is characterized
by very low seismicity. The only reported earthquake to have
occurred in this area is that of 464 b. c., a destructive event that
devastated the whole city of Sparta. In order to get information
on the occurrence of past earthquakes during the Holocene, results of different independent dating works that have performed
along the Sparta fault were used. These researchers confirm
the existence not only of the 464 B.C. earthquake but also of
several more that occurred at ca. 3900 b. c., 2500 B.C. and 2000
B.C., 550 A.D. and 1000 A.D. The events that occurred at 2500
and 464 B.C. should correspond to major events of magnitude
of the order of 7, which ruptured the entire length of the fault,
while these at 3900 B.C., 2000 B.C., 550 A.D. and 1000 A.D., to
smaller events of magnitude 6-6.5. The return periods of strong
earthquakes along the Sparta fault is estimated to be around
2000 years, but within these periods events of smaller magnitude
that ruptured segments of the fault have also occurred. В© 2005
Elsevier Ltd. All rights reserved.
LANDFORMS
1443 Neotectonic map of Syria and some aspects of Late
Cenozoic evolution of the northwestern boundary zone of the
Arabian plate
Rukieh M., Trifonov V.G., Dodonov A.E. et al. Journal of Geodynamics 2005 40/2-3 (235-256)
The neotectonic map of Syria, 1:500,000, was compiled by the
authors in 2003-2004. The map shows tectonic features formed
or continued to develop during the Neogene and Quaternary in
Syria and adjacent territories, including the Mediterranean realm.
The neotectonic structure of the region was formed as a result
of three phases of deformation. During the Early Miocene first
phase, the Arabian plate moved along the Dead Sea-Jordan segments of the Levant (Dead Sea) transform fault zone, Roum fault
and its continuation in the continental slope of the Mediterranean.
The chain of the coastal anticlines in the "Arabian" side of the
transform zone and the Lattaqie oblique (sinistral-thrust) boundary fault zone in the north were formed under the NNW-trending
compression. The Lattaqie zone continued by the Cyprus arc in
the west and by the Taurus (Bitlis) thrust in the east and further by
the Main Thrust of the Zagros. After "quiet" (for Syria) epoch
of the Middle Miocene when the Arabian plate moved to the
NE, during the Late Miocene second phase of deformation, the
Arabian plate moved again to the NNW along the same transform
boundary. But a part of the Late Miocene plate motion (up to
20 km) resulted by shortening in the Anti-Leban-Palmyride foldthrust belt that separated the Aleppo block from the main part of
the Arabian plate. During the Pliocene-Quaternary third phase
of deformation, the recent structural pattern of the Levant zone
was formed in Lebanon and the northwestern Syria. At the same
time, the Serghaya and smaller sinistral faults branched out the
Levant zone and the system of the W-E-trending convex to the
south dextral faults ruptured the Palmyrides and the stable part of
the Arabian plate. The total Pliocene-Quaternary sinistral offset
on the young Levant zone segments and the associated faults
has reached 35-40 km, like on the Dead Sea-Jordan segments of
the Levant fault zone. The faults, demonstrating the PlioceneQuaternary activity are still active now and represent the main
seismic zones in Syria. Offsets on them are mostly a cumulative
effect of strong earthquakes. В© 2005 Published by Elsevier Ltd.
1444 Paleoseismology in Venezuela: Objectives, methods,
applications, limitations and perspectives
Audemard M. F.A. Tectonophysics 2005 408/1-4 (29-61)
The privileged location of Venezuela along an active interplate
deformation belt, despite of being a "so-called" developing country, has led to a long paleoseismic tradition as attested by 45
trench assessments since 1968. Since then, a first 2-trench study
was carried out by the American Woodward-Clyde company
across the Oca fault at Sinamaica. Since 1980, all further paleoseismic studies have been performed by FUNVISIS and the
Uribante-Caparo hydroelectric project (southern MВґerida Andes)
became their first assessment where 22 huge trenches were bulldozer-dug. Except for these CompaЛњna AnВґonima de AdministraciВґon y Fomento ElВґectrico (CADAFE) financed trenches and
two others, all other assessments were for PetrВґoleos de Venezuela
S. A. -PDVSA-. In this paper, geographic and geologic factors, as
well as logistic limitations, conditioning success in paleoseismic
studies by trenching, shall be discussed based on the Venezuelan
experience developed over the years. The scientific contribution of this approach refer to: confirmation of Holocene fault
activity, slip-per-event and average slip rate of a given fault (or
segment), seismic potential (repeat of maximum credible earthquakes) of known faults, fault segmentation, fault interaction as
consequence of stress loading by stick-slip on contiguous faults,
time-space distribution of seismic activity along a given tectonic
feature, seismotectonic association of historical earthquakes and
landscape evolution on the short term and its implications on the
long-term evolution (poorly discussed since this is really part of
the field of Neotectonics). In recent years (since 1999), a new
approach has been introduced in Venezuela consisting in complementing the seismic history derived from trenching studies with
the evaluation of seismically induced perturbations in the continuous Quaternary sedimentary record of (either active or fossil)
lakes. The future of this discipline in Venezuela heads to more
trenching and lake coring in order to gather more data on the
previously mentioned aspects. Other paleoseismic approaches
have been developed very little in Venezuela since either climate
273
or the geodynamic setting do not favor their application. В© 2005
Elsevier B.V. All rights reserved.
1445 Some considerations concerning seismic geomorphology and paleoseismology
Dramis F. and Blumetti A.M. Tectonophysics 2005 408/1-4 (177191)
Seismic geomorphology studies landforms which developed in
connection with earthquakes. Among them, two different end
members may be distinguished: 1) seismo-tectonic landforms,
including surface faults and fractures, land uplift and subsidence
at different scales, surface bulges, elongate ridges, and any other
permanent ground deformations directly related to tectonic stress,
and 2) seismo-gravitational landforms, such as landslides, deepseated gravitational slope deformations, sinkholes, and fissures
due to sediment compaction or liquefaction and sand blows, connected with both seismic shaking and gravitational stress. A
clear-cut distinction between the two categories of landforms
is not always easy to make (and in many instances not really
useful), while there are, in many cases, ground effects that might
be (and should be) considered as simultaneous combinations of
seismo-tectonic and seismo-gravitational processes. This applies especially to surface fracturing and faulting which could
be the combined result of tectonic stress, stress produced by
seismic shaking, and gravitational stress. The objective of this
paper is to review selected case histories mainly from Italy and
the Mediterranean region, in order to show the importance of a
comprehensive study of earthquake-generated landforms for understanding the seismicity level of the area under investigation.
We argue that in earthquake prone areas, seismic landforms often
constitute typical patterns (seismic landscapes) whose recognition, mapping and paleoseismological analysis may help in the
evaluation of seismic hazards. В© 2005 Elsevier B.V. All rights
reserved.
Landforms of other planets
1446 Stratigraphy and sedimentology of a dry to wet eolian
depositional system, Burns formation, Meridiani Planum,
Mars
Grotzinger J.P., Arvidson R.E., Bell III J.F. et al. Earth and
Planetary Science Letters 2005 240/1 (11-72)
Outcrop exposures of sedimentary rocks at the Opportunity landing site (Meridiani Planum) form a set of genetically related
strata defined here informally as the Burns formation. This formation can be subdivided into lower, middle, and upper units
which, respectively, represent eolian dune, eolian sand sheet,
and mixed eolian sand sheet and interdune facies associations.
Collectively, these three units are at least 7 m thick and define a "wetting-upward" succession which records a progressive
increase in the influence of groundwater and, ultimately, surface water in controlling primary depositional processes. The
Burns lower unit is interpreted as a dry dune field (though grain
composition indicates an evaporitic source), whose preserved
record of large-scale cross-bedded sandstones indicates either
superimposed bedforms of variable size or reactivation of leeside slip faces by episodic (possibly seasonal) changes in wind
direction. The boundary between the lower and middle units is
a significant eolian deflation surface. This surface is interpreted
to record eolian erosion down to the capillary fringe of the water
table, where increased resistance to wind-induced erosion was
promoted by increased sediment cohesiveness in the capillary
fringe. The overlying Burns middle unit is characterized by finescale planar-laminated to low-angle-stratified sandstones. These
sandstones accumulated during lateral migration of eolian impact
ripples over the flat to gently undulating sand sheet surface. In
terrestrial settings, sand sheets may form an intermediate environment between dune fields and interdune or playa surfaces.
The contact between the middle and upper units of the Burns
formation is interpreted as a diagenetic front, where recrystallization in the phreatic or capillary zones may have occurred.
The upper unit of the Burns formation contains a mixture of
sand sheet facies and interdune facies. Interdune facies include
wavy bedding, irregular lamination with convolute bedding and
274
LANDFORMS
possible small tepee or salt-ridge structures, and cm-scale festoon
cross-lamination indicative of shallow subaqueous flows marked
by current velocities of a few tens of cm/s. Most likely, these
currents were gravity-driven, possibly unchannelized flows resulting from the flooding of interdune/ playa surfaces. However,
evidence for lacustrine sedimentation, including mudstones or
in situ bottom-growth evaporites, has not been observed so far
at Eagle and Endurance craters. Mineralogical and elemental
data indicate that the eolian sandstones of the lower and middle
units, as well as the subaqueous and eolian deposits of the Burns
upper unit, were derived from an evaporitic source. This indirectly points to a temporally equivalent playa where lacustrine
evaporites or ground-water-generated efflorescent crusts were
deflated to provide a source of sand-sized particles that were
entrained to form eolian dunes and sand sheets. This process
is responsible for the development of sulfate eolianites at White
Sands, New Mexico, and could have provided a prolific flux
of sulfate sediment at Meridiani. Though evidence for surface
water in the Burns formation is mostly limited to the upper unit,
the associated sulfate eolianites provide strong evidence for the
critical role of groundwater in controlling sediment production
and stratigraphic architecture throughout the formation. В© 2005
Elsevier B.V. All rights reserved.
Slopes
1447 Slope movements as a disturbance agent increasing heterogeneity and biodiversity of landscape in Eastern
Moravia
Kirchner K. and Lacina J. Ekologia Bratislava 2004 23/SUPPL.
1 (94-103)
The paper is devoted to the characterisation of complex relations
between vegetation cover and slope movements, especially sliding, in the Vsetn region in the eastern Moravia. The area is a
part of highland flysch relief of the Outer Western Carpathians,
where the extreme rainfall of July 1997 activated a lot of slope
deformations. It was recognised on the basis of biogeographic
(geobiocoenologic) and geomorphic investigations of 20 study
sites that landslides originate in various potential as well as actual vegetation types. The process of sliding alters the ecological
conditions of the site which results to the change of the geobiocoen type; slope movements as a disturbance agent increase the
landscape heterogeneity and biodiversity.
1448 An attempt to refine rockfall hazard zoning based on
the kinetic energy, frequency and fragmentation degree
Jaboyedoff M., Dudt J.P. and Labiouse V. Natural Hazards and
Earth System Science 2005 5/5 (621-632)
Rockfall hazard zoning is usually achieved using a qualitative
estimate of hazard, and not an absolute scale. In Switzerland,
danger maps, which correspond to a hazard zoning depending on
the intensity of the considered phenomenon (e.g. kinetic energy
for rockfalls), are replacing hazard maps. Basically, the danger
grows with the mean frequency and with the intensity of the
rockfall. This principle based on intensity thresholds may also
be applied to other intensity threshold values than those used
in Switzerland for rockfall hazard zoning method, i.e. danger
mapping. In this paper, we explore the effect of slope geometry
and roc kfall frequency on the rockfall hazard zoning. First,
the transition from 2D zoning to 3D zoning based on rockfall
trajectory simulation is examined; then, its dependency on slope
geometry is emphasized. The spatial extent of hazard zones is
examined, showing that limits may vary widely depending on
the rockfall frequency. This approach is especially dedicated
to highly populated regions, because the hazard zoning has to
be very fine in order to delineate the greatest possible territory
containing acceptable risks. В© 2005 Author(s). This work is
licensed under a Creative Commons License.
1449 The Influence of the North Atlantic Oscillation on rainfall triggering of landslides near Lisbon
Trigo R.M., ZЛ†ezere J.L., Rodrigues M.L. and Trigo I.F. Natural
Hazards 2005 36/3 (331-354)
The majority of landsliding episodes in the area north of Lisbon
are associated with rainfall events of short (less than 5 days)
medium (5-20 days) or long duration (more than 20 days). The
precipitation regime in Portugal is highly irregular, with large
differences between wet and dry years. We have assessed the
impact of the North Atlantic Oscillation (NAO) on both the winter
precipitation and the timing and magnitude of associated landslide events. Results show that the large inter-annual variability
of winter precipitation is largely modulated by the NAO mode.
The precipitation composite corresponding to high NAO index
presents a considerable lower median value (47 mm/month) than
the corresponding low NAO index class (134 mm/month). The
entire precipitation distribution associated with the low NAO index composite encompasses a wider range of values than the corresponding high NAO index composite. This non-linear behavior
is reflected in the probability of occurrence of a very wet month
(precipitation above the 90% percentile) that is just 1% for the
positive NAO class and 23% for low NAO index months. Results
for the low NAO class are crucial because these months are more
likely associated with long-lasting rainfall episodes responsible
for large landslide events. This is confirmed by the application of
a 3-month moving average to both NAO index and precipitation
time series. This procedure allowed the identification of many
months with landslide activity as being characterized by negative
average values of the NAO index and high values of average precipitation (above 100 mm/month). Finally, using daily data we
have computed the return periods associated with the entire set of
landslide episodes and, based on these results, obtained a strong
linear relationship between critical cumulative rainfall and the
corresponding critical rainfall event duration. В© Springer 2005.
1450 Case history of landslide movement during the
Northridge earthquake
Pradel D., Smith P.M., Stewart J.P. and Raad G. Journal of
Geotechnical and Geoenvironmental Engineering 2005 131/11
(1360-1369)
We document a case history of Northridge earthquake induced
movement of a coherent landslide mass comprised principally
of weathered, previously sheared siltstone. Information on the
residual shear strength of the material through which the sliding
occurred is available both from backanalysis of a static (rainfall-induced) failure on the same slope and laboratory test data.
Postearthquake field reconnaissance data establishes the seismic
slope displacements near the slope crest. A yield coefficient is
estimated for the slope based on residual shear strengths and
measured groundwater levels at the time of the Northridge earthquake. This yield coefficient is used with four horizontal equivalent acceleration time histories (that approximate the seismic
demand within the slide mass) in Newmark sliding block displacement analyses. The calculated displacements range from
approximately 20 to 90 mm, which compares well with observed
displacements at the slide scarp of approximately 50 mm. Journal
of Geotechnical and Geoenvironmental Engineering В© ASCE.
1451 Reliability analysis of unsaturated soil slopes
Sivakumar Babu G.L. and Murthy D.S.N. Journal of Geotechnical and Geoenvironmental Engineering 2005 131/11 (14231428)
Many soil slopes are unsaturated in their initial state, and suction
contributes to initial stability. Stability of these slopes decreases
as suction decreases with time due to rainfall infiltration and
water redistribution. Many of the parameters in the assessment
of stability are highly variable. In this technical note, sensitivity/reliability analysis of design variables for a typical unsaturated soil slope is conducted. Sensitivity analysis shows that
suction parameters have significant influence on the stability. Reliability computations performed for the slope considered show
that failure zones are better captured by the reliability index than
the conventional factor of safety. The study also shows that variation of saturated hydraulic conductivity significantly influences
slope reliability. Journal of Geotechnical and Geoenvironmental
Engineering В© ASCE.
1452 On the use of Saint Venant equations to simulate the
spreading of a granular mass
Mangeney- Castelnau A., Bouchut F., Vilotte J.P. et al. Journal
of Geophysical Research B: Solid Earth 2005 110/9 (1-17)
LANDFORMS
Cliff collapse is an active geomorphological process acting at
the surface of the Earth and telluric planets. Recent laboratory
studies have investigated the collapse of an initially cylindrical
granular mass along a rough horizontal plane for different initial
aspect ratios a = Hi /Ri , where Hi and Ri are the initial height
and radius, respectively. A numerical simulation of these experiments is performed using a minimal depth-integrated model
based on a long-wave approximation. A dimensional analysis
of the equations shows that such a model exhibits the scaling
laws observed experimentally. Generic solutions are independent of gravity and depend only on the initial aspect ratio a and
an effective friction angle. In terms of dynamics, the numerical
simulations are consistent with the experiments for a 1. The
experimentally observed saturation of the final height of the deposit, when normalized with respect to the initial radius of the
cylinder, is accurately reproduced numerically. Analysis of the
results sheds light on the correlation between the area overrun by
the granular mass and its initial potential energy. The extent of
the deposit, the final height, and the arrest time of the front can
be directly estimated from the "generic solution" of the model for
terrestrial and extraterrestrial avalanches. The effective friction,
a parameter classically used to describe the mobility of gravitational flows, is shown to depend on the initial aspect ratio a.
This dependence should be taken into account when interpreting
the high mobility of large volume events. Copyright 2005 by the
American Geophysical Union.
1453 Classifying and assessing the geologic contribution to
rockfall hazard
Vandewater C.J., Dunne W.M., Mauldon M. et al. Environmental
and Engineering Geoscience 2005 11/2 (141-154)
Rockfalls from roadcuts are a major hazard and pose problems
for transportation agencies across the country. In the context
of rockfall hazard management, however, no consensus exists
about the role of geology in assessing rockfall hazard. This
study investigates the geologic contribution to rockfall hazard
through application of rockfall hazard rating systems to roadcuts
in Tennessee and through additional data collection to reveal correlations between hazard characteristics and geologic attributes.
The geologic character of 80 roadcuts in central and eastern Tennessee was evaluated using the Tennessee Rockfall Hazard Rating System (RHRS), which is a revision of the National Highway
Institute (NHI) RHRS. Scores for both RHRSs were compared to
evaluate whether the improved reproducibility of scoring for the
Tennessee RHRS yielded unintended losses of scoring accuracy
and sensitivity. Additional geologic attribute data beyond those
used in the RHRS system were collected to determine with logistic regression analysis whether relationships among the geologic
attributes, rockfall type, and block size exist. Results indicate
the revised geologic component of TennesseeвЂ™s RHRS is more
informative and permits description of a wider spectrum of geologic conditions than does the NHI version. Logistic regression
analysis indicates rockfall type correlates to lithologic variation
and the number of discontinuity sets; and block size correlates to
structurally controlled rockfall, lithologic variation, mechanical
layer thickness, and number of discontinuity sets. Consequently,
roadcuts containing potential rockfall modes with two or more
discontinuity sets, no lithologic variation, and mechanical thicknesses that exceed 1.0 m are expected to have greater Geologic
Character scores.
1454 Risk-based definition of zones for land-use planning in
snow avalanche terrain
McClung D.M. Canadian Geotechnical Journal 2005 42/4
(1030-1038)
For avalanche applications, the definition of zones for land-use
planning typically involves estimates of both return period and
impact pressures as functions of position in the runout zone.
Since return period is related to expected avalanche frequency
and impact pressure is related to consequences if structures are
bit, zone specifications imply a risk-based approach. In this
paper, the schemes for definition of zones from three countries
(Switzerland, Canada, and Austria) are presented and compared
from a mathematical, risk-based framework. The comparison
reveals that the Swiss standard is the least conservative and the
Austrian standard is the most conservative. В© 2005 NRC Canada.
275
1455 Geological and morphological study of the Jiufengershan landslide triggered by the Chi-Chi Taiwan earthquake
Chang K.- J., Taboada A. and Chan Y.- C. Geomorphology 2005
71/3-4 (293-309)
The Jiufengershan rock and soil avalanche is one of the largest
landslides triggered by the Chi-Chi earthquake Taiwan 1999. The
landslide destabilized the western limb of the Taanshan syncline
along a weak stratigraphic layer. It involved a flatiron remnant,
which was almost entirely mobilized during the earthquake. The
avalanche was slowed down by NS trending ridges located downstream along the Jiutsaihu creek. The landslide affected a 60 m
thick and 1.5 km long sedimentary pile composed of shales and
sandstones, which dip 22В°SE toward a transverse valley. The
triggering mechanism and the sliding process were analyzed by
means of geological and morphological data from aerial photographs and observed in the field. A high-resolution airborne
Light Detection and Ranging (LiDAR) image taken 2.5 years after the landslide allows the identification of morphological structures along the sliding surface and the landslide accumulation.
The sliding surface shows several deformation structures such as
fault scarps and folds. These structures are interpreted in terms
of basal shear stresses created during the avalanche. Three major
joint sets were identified at the sliding surface. The isopach map
of the landslide was calculated from the comparison between
elevation models before and after the earthquake. The coseismic
volume of mobilized material and landslide deposit data are 42
106 m3 and 50 106 m3 , respectively. The geometry of the
landslide accumulation in the field has an irregular star shape.
The morphology of the deposit area shows a sequence of smooth
reliefs and depressions that contrast with the neighboring ridges.
В© 2005 Elsevier B.V. All rights reserved.
1456 The 1786 earthquake-triggered landslide dam and subsequent dam-break flood on the Dadu river, southwestern
China
Chanson H. Geomorphology 2005 71/3-4 (437-440)
Forensic studies of past hydraulic structure failures are rare despite their critical relevance to modern hydraulic design, and the
writers (Dai et al., 2005) must be congratulated for their outstanding study. Herein the discussion is focused on two aspects
of the conclusion. It is believed that dam overtopping was the
primary cause of the Dadu river landslide dam failure, although
aftershocks may have further weakened the embankment. Using
physically based equations supported by recent physical model
data, the maximum outflow may be estimated to be about 6000
m3 /s. В© 2005 Elsevier B.V. All rights reserved.
1457 The statistical relationship between unconfined compressive strengths and the frequency distributions of slope
gradients - A case study in northern Hungary
PВЁuspВЁoki Z., SzabВґo S., Demeter G. et al. Geomorphology 2005
71/3-4 (424-436)
This paper focuses on the question of whether there is a deterministic connection between the slope gradient and unconfined
compression strength (UCS) as a lithological factor and on describing the nature of this connection. Moreover, the authors
determined the sensitive statistical parameters in the statistical
surface analyses. The surface analyses were carried out in an
area extending over 1500 km2 in northern Hungary and containing parts of the uplifted Palaeozoic and Mesozoic basement and
the semi-consolidated material of the Palaeogene and Neogene
molasse sediments. The 67 geological formations of the area
were grouped into 10 petrophysical categories characterised by
unconfined compressive strength as a petrophysical parameter.
The geological database was the digitalized geological map of
North Hungarian Region (1 : 100 000). The digital topographic
database was based on 10 m contour lines of 1 : 50 000 maps, the
digital elevation model was generated by kriging interpolation.
Three topographic models were created with resolutions of 25
25, 50 50 and 100 100 m per pixels. Evident correlation can
be shown between the UCS and the relative frequency of the slope
gradient. The adequate regression procedure is the power regression for low slope category values while logarithmic regression
is applicable at high slope angles. Based on the characteristic
of the relationship and the value of r2 , slope category intervals
can be identified the relative frequency of which is proven to be
determined by the UCS. These intervals are found to be between
276
LANDFORMS
4-10%, 10-16%, 16-22%, 22-44% and over 44%. Using the determination equations of slope gradient between 4-10% and over
44%, the UCS of the bedrock can be calculated approximately as
the average value of the two calculated results. So the quotient
of the frequency of these two category intervals can be regarded
as an important morphometric index for a given bedrock. From
the aspect of petrophysical characteristics, the rock with UCS
between 6 and 86 MPa were proven to be deterministic for the
slope development i.e. in the determination of the slope category
frequencies. Applying the relative frequency of slope gradients a
relative erosion resistance of the petrophysical categories can be
calculated. Considering the determination coefficients, among
the statistical parameters of the distribution of slope category
values the standard deviation, mode, mean and median proved to
be determined by the UCS of the bedrock. В© 2005 Elsevier B.V.
All rights reserved.
1458 Analysis of dynamic factors of debris landslide by
means of the model of quantitative theory - Using the Xintan
landslide, China, as an example
Keqiang H., Jibao Y. and Sijing W. Environmental Geology 2005
48/6 (676-681)
If prediction of a debris landslide is to be completed, the first
problem is how to determine and correlate the dynamic factors.
The special composition and complicated geological conditions
of debris landslides have many dynamic factors influencing displacement and stability. Correlations are generally very complicated. The relationship and sequence of factors is too complex
to be completed by traditional mathematical model. In order
to solve the problem above, a systematical study of the quantitative and qualitative dynamic factors using a model of the
quantitative theory was performed based on the displacements
of Xintan landslide, China. Rainfall was found to be the most
important dynamic factor among the six factors controlling displacements. Relative importance sequence and correlation was
also established. All prediction results agree with the mechanism
and displacement pattern of the Xintan landslide. Optimized
measures of prevention and control for debris landslides can be
completed with correlation of the dynamic factors by means of
the quantitative theory model. В© Springer-Verlag 2005.
1459 Distribution of landslides adjacent to the northern side
of the Yarlu Tsangpo Grand Canyon in Tibet, China
Shang Y., Park H.- D., Yang Z. and Yang J. Environmental Geology 2005 48/6 (721-741)
This paper presents results of recent studies on distribution and
category of landslides in one section of the Sichuan-Tibet Highway, adjacent to the northern side of the Yarlu Tsangpo Grand
Canyon, Tibet, Southwestern China. In the tectonic setting predominated by compression and strike-slipping, active faults are
dominant and result in the genesis of the great alpine relief together with fluvial incision and unloading. In this section, with
a distance of about 290 km between Ranwu and Lulang, 34
landslides occurred. Among them, the 12 large and super-large
landslides comprise the most dangerous part of the highway system to road users over the past 50 years. The landslides usually
occurred in slopes comprised of moraine with a large thickness,
fluvio-pluvial and lacustrine deposits and fractured rocks. Based
on the examination of the physical geography, structural geology, Quaternary geology, stratigraphy and petrography, this paper
presents the temporal-spatial distribution of landslides along the
section and classification of them into three types with respect
to mechanism and composites of landslides. Type 1. Landslide
initiated at high elevation and transformed into a distal debris
flow damming the river with a long reoccurrence interval Type 2.
Landslide at stream banks, in different ranks of mass movements
in dissecting layers of moraines Type 3. Landslide of fractured
rock mass with quick translation movements. Each of the three
types is presented by distinctive case examples. Type 1 is Yigong
Landslide; type 2 includes Dongjiu Landslide group, 102 Landslide group, Suotong Landslide group, Songzong Landslide; and
the type 3 is Layue Landslide. A binary landslide, which is
seldom seen in nature and which occurred in the outlet of one
creek under the integrative function of fluvial incision and road
cut, is also presented. These are distributed in different parts of
the area with characterized structural geology, topography and
composites (gneiss and Quaternary deposits) with accumulative
quantity between Suotong and Dongjiu. The most occurred with
frequent and rapid translation, shallow shearing planes, various
influential factors and unique triggering factors, and a variable period of reoccurrence with a tendency of increasing magnitude. In
this region, six influential factors greatly contribute to their occurrence: (a) intensive neotectonic movements, (b) ongoing alpine
canyon relief, (c) earthquakes, (d) heavy precipitation, (e) stream
erosion, and (f) human activities, to a certain extent. Mostly, the
latter four factors play major roles in triggering landslide occurrence. The earthquake causes the rock and soil to fracture and
deform, and tends to be unstable, or cause earth-induced landslides. The heavy rainfall in monsoon seasons which saturates the
soil and lower the shearing strength is mostly responsible for the
occurrence of landslides. The stream erosion disturbs slope toes
causing progressive failure. Road construction and deforestation
decrease the natural slope stability. Comments and suggestions
on the physical measures for remediation of landslides and safety
of highways are also made. В© Springer-Verlag 2005.
1460 Location of critical three-dimensional non-spherical
failure surface by NURBS functions and ellipsoid with applications to highway slopes
Cheng Y.M., Liu H.T., Wei W.B. and Au S.K. Computers and
Geotechnics 2005 32/6 (387-399)
At present, location of critical three-dimensional failure surfaces
is mainly limited to spherical shape due to the various difficulties in performing global optimization for general non-spherical
failure surface. Non-spherical failure surface is however the
most general and critical shape that should be considered in
slope stability analysis. This paper introduces a practical way
in using NURBS surface and ellipsoidal surface to simulate a
three-dimensional sliding surface. Numerical examples have
indicated that the present proposal is effective in application and
the critical failure surfaces as determined for 2 specially designed
problems are also reasonable. The authors have also applied the
optimization search to a curved highway slope and have obtained
the relation between curvature of slope and the minimum factors
of safety of slope. В© 2005 Elsevier Ltd. All rights reserved.
Soil mechanics
1461 Engineering-related slope failure in permafrost regions
of the Qinghai-Tibet Plateau
Niu F., Cheng G., Ni W. and Jin D. Cold Regions Science and
Technology 2005 42/3 (215-225)
Thaw slumping existing on two slopes in permafrost region of the
Qinghai-Tibet Plateau is studied with their geological features,
deformations and ground temperature in this paper. The failure
shows as collapse and slide of active layer along the massive
ground-ice surface. The field-monitored data show that the retrogressively extending area, soil-body sliding velocity and the
water content of the soils in the failed area strikingly change
with the air temperature and slope facing aspect. On the southfacing slope, the values of all of these items are higher than that
on the north-facing slope. The mean annual ground temperature
in the failed area on the south-facing slope is evidently higher
than that in the undisturbed natural ground and that in the northfacing slope. In addition, the input of heat into the permafrost
below the sliding mass on the south-facing slope is more than the
output. Therefore the permafrost in the slope processes degradation when landslide occurs. The genesis of this kind of slope
failure is closely related to ice-rich frozen soils and activities of
engineering cut. Based on static balance analysis, the stability
estimating method for such landslide is presented considering
the seepage of ice-melting ground water in the paper. At last, the
engineering measures of preventing thaw slumping are proposed
too. В© 2005 Elsevier B.V. All rights reserved.
1462 Numerical analysis of a landslide in soils with strainsoftening behaviour
Troncone A. Geotechnique 2005 55/8 (585-596)
The results of an analysis concerning a landslide of great dimensions, which occurred at Senise (Southern Italy) on 26 July 1986,
are presented. The landslide was of a translational type, and the
LANDFORMS
failure developed within a thin clayey silt layer interbedded by a
slightly cemented sand formation. Both these soils experienced
a pronounced strain-softening behaviour during laboratory tests.
From the analyses performed using the traditional limit equilibrium approach, it has been found that the average operational
resistance along the sliding surface was less than that of the
peak and greater than the residual resistance deduced from the
laboratory tests. As a consequence, it has been postulated that a
progressive failure had occurred. Such a failure process can be
appropriately studied using methods that are capable of simulating the formation and development of shear zones, where strain is
localised. From a computational point of view this presents many
difficulties, because the numerical procedures currently used are
very often affected by a lack of convergence, and the solution
may depend strongly on the mesh adopted. In order to overcome
these numerical drawbacks, in the present study use is made of
both an elasto-viscoplastic constitutive model and a non-local
elasto-viscoplastic model implemented in a finite element code.
The Mohr-Coulomb plastic law is adopted, and the strain-softening behaviour of the soil is simulated by reducing the strength
parameters with the accumulated deviatoric plastic strains. The
results of the analysis show that a progressive failure occurred
owing to deep excavations carried out at the toe of the slope. In
addition, the soil mass involved in the sliding and the location
of the failure surface deduced from the numerical simulation are
found to be very similar to those observe.
Karst
1463 Modeling the influence of epikarst evolution on karst
aquifer genesis: A time-variant recharge boundary condition
for joint karst-epikarst development
Bauer S., Liedl R. and Sauter M. Water Resources Research 2005
41/9 (1-12)
[1] The epikarst, a zone of increased weathering near the land
surface, determines the distribution of recharge to a karst aquifer
in both space and time. It links climatic and near-surface geological conditions with the karstification of a limestone aquifer,
defining both the hydraulic and the chemical boundary conditions
for the development of the karst system. Realistic modeling
of the epikarst is therefore a prerequisite for the simulation of
karst aquifer genesis. A conceptual model of the joint karstepikarst evolution is presented in this paper. An epikarst module
is developed and implemented in a numerical continuum-discrete
conduit flow model for karst genesis, which accounts for the joint
evolution of the epikarst and the main karstic conduit network
under unconfined conditions. The influence of epikarst genesis
on the evolution of the underlying karst aquifer is investigated in
four scenarios. It is found that only the interaction of epikarst
and initial heterogeneity in the underlying carbonate rock leads
to the development of a dendritic cave system. If no heterogeneity in the initial conduit network or in the recharge distribution
is included, maze-type caves develop. Copyright 2005 by the
American Geophysical Union.
1464 Solution-collapse breccias of the Minkinfjellet and
Wordiekammen Formations, Central Spitsbergen, Svalbard:
A large gypsum palaeokarst system
Eliassen A. and Talbot M.R. Sedimentology 2005 52/4 (775-794)
Large volumes of carbonate breccia occur in the late syn-rift
and early post-rift deposits of the Billefjorden Trough, Central
Spitsbergen. Breccias are developed throughout the Moscovian
Minkinfjellet Formation and in basal parts of the Kazimovian
Wordiekammen Formation. Breccias can be divided into two
categories: (i) thick, cross-cutting breccia-bodies up to 200 m
thick that are associated with breccia pipes and large V-structures,
and (ii) horizontal stratabound breccia beds interbedded with undeformed carbonate and siliciclastic rocks. The thick breccias
occur in the central part of the basin, whereas the stratabound
breccia beds have a much wider areal extent towards the basin
margins. The breccias were formed by gravitational collapse into
cavities formed by dissolution of gypsum and anhydrite beds in
the Minkinfjellet Formation. Several dissolution fronts have
been discovered, demonstrating the genetic relationship between
dissolution of gypsum and brecciation. Textures and structures
277
typical of collapse breccias such as inverse grading, a sharp flat
base, breccia pipes (collapse dolines) and V-structures (cave roof
collapse) are also observed. The breccias are cemented by calcite
cements of pre-compaction, shallow burial origin. Primary fluid
inclusions in the calcite are dominantly single phase containing
fresh water (final melting points are ca 0В°C), suggesting that
breccia diagenesis occurred in meteoric waters. Cathodoluminescence (CL) zoning of the cements shows a consistent pattern
of three cement stages, but the abundance of each stage varies
stratigraphically and laterally. 18 O values of breccia cements
are more negative relative to marine limestones and meteoric cements developed in unbrecciated Minkinfjellet limestones. There
is a clear relationship between 18 O values and the abundance
of the different cement generations detected by CL. Paragenetically, later cements have lower 18 O values recording increased
temperatures during their precipitation. Carbon isotope values of
the cements are primarily rock-buffered although a weak trend
towards more negative values with increasing burial depth is
observed. The timing of gypsum dissolution and brecciation was
most likely related to major intervals of exposure of the carbonate platform during Gzhelian and/or Asselian/Sakmarian times.
These intervals of exposure occurred shortly after deposition of
the brecciated units and before deep burial of the sediments. В©
2005 International Association of Sedimentologists.
1465 Gypsum karst and its evolution east of Hafik (Sivas,
Turkey)
ВЁ
DoЛ‡gan U. and Ozel
S. Geomorphology 2005 71/3-4 (373-388)
Sivas and its surroundings is the most important gypsum karst terrain in Turkey with a massive Lower Miocene gypsum formation
750 m thick. The region east of Hafik has a wide variety of well
developed karstic features such as karrens, dissolution dolines,
collapse dolines, blind valleys, karstic springs, swallow holes,
caves, unroofed caves, natural bridges, gorges and poljes. The
karstification started in the Early Pliocene. The piezometric level
to the east of Hafik has lowered at least 200 m since the Early
Pliocene and 90-100 m since the Early Pleistocene. There is a
youthful karst (doline karst) on the Higher Plateau (1520-1600 m)
and a mature karst on Lower Plateau (1315-1420 m). The mature
karst evolved in two stages, first stage where excessively karstic
paleovalleys, uvalas and collapse dolines appear and the second stage where poljes, collapse dolines and degraded collapse
dolines dominated. В© 2005 Elsevier B.V. All rights reserved.
1466 Land subsidence and caprock dolines caused by subsurface gypsum dissolution and the effect of subsidence on
the fluvial system in the Upper Tigris Basin (between BismilBatman, Turkey)
DoЛ‡gan U. Geomorphology 2005 71/3-4 (389-401)
Karstification-based land subsidence was found in the Upper
Tigris Basin with dimensions not seen anywhere else in Turkey.
The area of land subsidence, where there are secondary and
tertiary subsidence developments, reaches 140 km2 . Subsidence
depth ranges between 40 and 70 m. The subsidence was formed
as a result of subsurface gypsum dissolution in Lower Miocene
formation. Although there are limestones together with gypsum
and Eocene limestone below them in the area, a subsidence with
such a large area is indicative of karstification in the gypsum.
The stratigraphical cross-sections taken from the wells and the
water analyses also verify this fact. The Lower Miocene gypsum,
which shows confined aquifer features, was completely dissolved
by the aggressive waters injected from the top and discharged
through by Zellek Fault. This resulted in the development of
subsidence and formation of caprock dolines on loosely textured
Upper Miocene-Pliocene cover formations. The Tigris River runs
through the subsidence area between Batman and Bismil. There
are four terrace levels as T1 (40 m), T2 (30 m), T3 (10 m) and
T4 (4-5 m) in the Tigris River valley. It was also found that there
were some movements of the levels of the terraces in the valley
by subsidence. The subsidence developed gradually throughout
the Quaternary; however no terrace was formed purely because
of subsidence. В© 2005 Elsevier B.V. All rights reserved.
278
THE QUATERNARY
1467 Analysis of karst hydrodynamics through comparison of dissolved and suspended solidsвЂ™ transport (French)
(Fonctionnnement hydrodynamique des systèmes karstique par
comparaison du transport du matВґeriel dissous et particulaire)
Valdes D., Dupont J.- P., Massei N. et al. Comptes Rendus Geoscience 2005 337/15 (1365-1374)
In karst systems, rain events often result in a decrease of the conductivity (a tracer of dissolved phase transport) and an increase
in turbidity (a tracer of suspended solids transport) at wells and
springs. This study shows that the comparison of suspended
solids and solute transport by the coupled approach of T - C
curves (Turbidity-Conductivity) and autocorrelations gives evidence of the transport processes in the karst network and allows
understanding the karst hydrodynamics. В© 2005 AcadВґemie des
sciences. Published by Elsevier SAS. All rights reserved.
Anthropogenic landforms
1468 Methods for the characterization of areas sensitive to
desertification: An application to the Calabrian territory
(Italy)
Coscarelli R., Minervino I. and Sorriso- Valvo M. IAHS-AISH
Publication 2005 -/299 (23-30)
Desertification, as it has been defined by the United Nations
Convention to Combat Desertification (UNCCD), represents the
whole phenomena of land degradation, resulting from many
causes. Southern European countries are considered as areas of
new expansion of desertification, caused by inadequate agricultural practices, overgrazing, and deforestation, which increase
anthrophic pressure. During the last few years, in the context
of several international research projects, methodologies were
proposed, based on various parameters. These are grouped in
uniform classes and weighted by the attribution of scores in order to assess the so-called "quality indexes". By computation
of the previous indexes, "desertification indicators" are defined.
This work reviews the most-used methodologies and presents
an application of the methodology proposed in the European
MEDALUS project to an area of the Calabrian territory (southern
Italy), relative to the physical aspects.
1469 Landscape change and sandy desertification in arid areas: A case study in the Zhangye Region of Gansu Province,
China
Luo F., Qi S.Z. and Xiao H.L. Environmental Geology 2005 49/1
(90-97)
The Zhangye Region of Gansu Province is an important agricultural base in arid northwestern China. During the twentieth
century, especially in the last five decades, the region has experienced sandy desertification. To document the status and causes
of this deterioration, satellite images, meteorological and socioeconomic data to assess landscape change from 1993 to 2002
were interpreted and analyzed. The results show that during the
intervening 9-year period the area of sandy lands has increased
by 642.2 km2 , which consist of aeolian sand dune (357.1 km2 )
and potential sandy land (216.3 km 2 ). Although the development and reversion of sandy desertification co-exist, the sandy
desertification in this area seems serious and is attributable to the
irrational use of water and land. В© Springer-Verlag 2005.
THE QUATERNARY
Chronology
1470 Lower Azilian at Cueva Oscura de Ania (Las Regueras,
Asturias, Spain) (French) (LвЂ™Azilien ancien de Cueva Oscura
de Ania (Las Regueras, Asturias, Espagne))
Вґ
AdВґan Alvarez
G.E., Garca SВґanchez E. and Quesada LВґopez J.M.
Anthropologie 2005 109/3 (499-519)
Recent definition of the Cantabrian Lower Azilian has turned
the Late Upper Magdalenian/Azilian transition into one of the
most interesting archaeological ages in the area. This period is
considered representing the earliest Azilian groups in Asturias.
Critic review of Cueva Oscura de Ania record, in the center of
Asturias, has allowed us to give full details of the Lower Azilian
archaeological characteristics. Cueva Oscura de Ania archaeological collection shows archaic traits, close to those from Cueva
de Los Azules and Cueva de La Riera, two eastern asturian sites.
These likenesses suggest a high stylistic and technical uniformity in distant areas during a critical period, when Palaeolithic
groups changed their subsistence strategies. Cueva Oscura de
Ania archaeological and polinic records suggest that this deposit
was built at the beginning of the paleoclimatic phase known as
AllerВЁod/ Cantabrian VIII (12 000-10 800 BP), when numerous
cantabrian sites suffered high erosion processes. All these circumstances convert Cueva Oscura de Ania in a fundamental site
to get a best knowledge of the origin and development of the
Cantabrian Azilian. The study of its bone collection allows us
outline new hypothesis about this archaeological period. В© 2005
PubliВґe par Elsevier SAS.
1471 Norwegian conifer chronologies constructed to date
historical timber
Thun T. Dendrochronologia 2005 23/2 (63-74)
Tree-ring chronologies have been constructed for Scots pine (Pinus sylvestris L.) from central Norway (TrГёndelag), west Norway
and south-east Norway back to 552, 765 and 871, respectively.
The purpose was to enable the dendrochronological dating of medieval and post-medieval timber constructions and other wooden
artefacts, and this proved to be possible. Absolute dates of floating chronologies based on medieval building material from urban
excavations in Trondheim, Bergen and Oslo were also obtained.
In northern Norway, samples taken from recently living Scots
pines in Troms have enabled the construction of a chronology
back to 1294. Chronologies based on samples taken from timber
constructions built of Norway spruce (Picea abies (L.) Karst.)
have been constructed for central Norway (TrГёndelag) and outer
Oslofjord back to 1351 and 1466, respectively. Historical events
have influenced the availability of building timber. Although
much material is available from the early and post-medieval periods, hardly any constructions have been found dating from an
approximately 60-year period after the Black Death in 13491350. The various regional chronologies based on Scots pine
have a matching tree-ring pattern with high t values and sign tests
at a 99.9% level of significance. The match between Norwegian
chronologies and chronologies constructed in Sweden also give
high t values and sign tests at a 99.9% level of significance. В©
2005 Elsevier GmbH. All rights reserved.
1472 Radiocarbon evidence for annual growth rings in the
deep-sea octocoral Primnoa resedaeformis
Sherwood O.A., Scott D.B., Risk M.J. and Guilderson T.P. Marine Ecology Progress Series 2005 301/- (129-134)
The deep-sea gorgonian octocoral Primnoa resedaeformis is distributed throughout the Atlantic and Pacific Oceans at depths of
65 to 3200 m. It has a 2-part skeleton of calcite and gorgonin.
Towards the inside of the axial skeleton gorgonin and calcite
are deposited in concentric growth rings, similar to tree rings.
Colonies were collected from the NE Channel (NW Atlantic
Ocean, southwest of Nova Scotia, Canada) from depths of 250 to
475 m. Radiocarbon was measured in individual rings isolated
from sections of each colony, after dissolution of calcite. Each
14 C measurement was paired with a ring age determined by 3
amateur ring counters. The precision of ring counts averaged
better than
2 yr. Accurate reconstruction of 20th century
bomb-radiocarbon showed that (1) the growth rings are formed
annually, (2) the gorgonin is derived from surface particulate
organic matter (POM) and (3) useful environmental data are
recorded in the organic endoskeletons of deep-sea octocorals.
These results support the use of P. resedaeformis as a long-term,
high resolution monitor of ocean surface conditions, particularly
in temperate and boreal environments where proxy data are lacking. В© Inter-Research 2005.
THE QUATERNARY
1473 Characteristics and sources of tephra layers in the
EPICA-Dome C ice record (East Antarctica): Implications
for past atmospheric circulation and ice core stratigraphic
correlations
Narcisi B., Petit J.R., Delmonte B. et al. Earth and Planetary
Science Letters 2005 239/3-4 (253-265)
Thirteen discrete air-fall tephra layers were identified in the last
200,000-yr section of the EPICA-Dome C ice record drilled
in the East Antarctic plateau (75В°06 S, 123В°21 E). Quantitative grain size, glass particle morphology, and the grain-discrete
major element composition of the glass fraction of these layers were investigated. Through comparison with literature data
on the rock composition of Quaternary volcanic centres located
within and around Antarctica, five tephra layers were attributed
to South Sandwich volcanoes in the South Atlantic Ocean, two
to South Shetland volcanoes (northern Antarctic Peninsula), two
to Andean volcanoes, and four to Antarctic (Marie Byrd Land
and Melbourne) provinces. The abundance of layers originating
in the southern part of the Atlantic confirms that westerly atmospheric circulation spiralling towards East Antarctica prevailed
over the last 200 ka. Moreover, the record of events from Antarctic centres suggests that atmospheric trajectories from West
to East Antarctica can also be significant. A few ash layers
are geochemically distinct and appear equivalent to levels from
Vostok and Dome Fuji deep ice records, located ca. 600 km
and ca. 2000 km, respectively, from Dome C on the Antarctic
plateau. These layers provide unambiguous markers for future
correlation with other Antarctic ice cores and circumpolar marine
climatic records. They also provide reliable constraints to get a
common timescale by glaciological modelling, and represent a
first step towards absolute ice core dating. В© 2005 Published by
Elsevier B.V.
1474 First dating of protohistorical forest clearings on the
Vosges grasslands (Rossberg, Haut-Rhin, France). A pedoanthracological study (French) (Premières datations directes
de dВґefrichements protohistoriques sur les chaumes secondaires
des Vosges (Rossberg, Haut-Rhin). Approche pВґedoanthracologique)
Schwartz D., Thinon M., Goepp S. et al. Comptes Rendus Geoscience 2005 337/14 (1250-1256)
The age of the upland grasslands of the Vosges Mountains is still
not well known. On the basis of the study of historical archives, it
was assumed that the forest clearings, which led to grasslands establishment, were done by the monks who colonized the Vosges
valleys between the 7th and the 8th centuries. Our pedo-anthracological study raises questions about this hypothesis, based
on the discovery of Juniperus communis charcoal in soils from
the 2nd or 1st century BC. This plant specie is characteristic of
grasslands developing into fallows. The occurrence of Juniperus
communis charcoals indicates that upland grasslands did exist at
least 800 years earlier than it was expected before our study, i.e.
at least since the late Iron Age. В© 2005 AcadВґemie des sciences.
PubliВґe par Elsevier SAS. Tous droits rВґeservВґes.
1475 The age of the Paludi Formation: A major constraint
to the beginning of the Apulia-verging orogenic transport in
the northern sector of the Calabria-Peloritani Arc
Bonardi G., De Capoa P., Di Staso A. et al. Terra Nova 2005
17/4 (331-337)
A stratigraphic revision of the Paludi Formation, cropping out in
Northern Calabria on the north-eastern side of Sila Massif, has
confirmed that it has been deposited between two main tectonic
phases. Actually the formation is involved only by top to the
north-east thrusts, different from those separating the crystalline
and ophiolitic nappes of Northern Calabria, and rests unconformably on the Sila Unit, the uppermost nappe of the tectonic
stack. In the frame of the interpretation of Northern Calabria as a
fragment of the Alps, the Paludi Formation play the role of a deposit post-dating the eo-alpine tectonic phases and pre-dating the
Apenninic orogenic transport. Therefore the Aquitanian age of
the formation, obtained by nannofloras analyses, can be considered the minimum age to the Apuliaverging orogenic transport,
witnessed by top to north-east thrusts. It fairly corresponds to the
age referred to the Lucanian ocean closure. В© 2005 Blackwell
Publishing Ltd.
279
1476 Pleistocene geomorphology and geochronology of eastern Grand Canyon: Linkages of landscape components during climate changes
Anders M.D., Pederson J.L., Rittenour T.M. et al. Quaternary
Science Reviews 2005 24/23-24 (2428-2448)
We report new mapping, soils, survey, and geochronologic (luminescence, U-series, and cosmogenic-nuclide) data from Pleistocene deposits in the arid setting of eastern Grand Canyon. The
result is a stratigraphic framework of inset fill gravels and associated terraces that provide a record of the responses of hillslopes,
tributary streams, and the Colorado River to the last 400 kyr of
glacial-interglacial climate change. The best-preserved last 80
kyr of this record indicates a stratigraphic-chronologic disconnect between both deposition and incision along the Colorado
River versus along the trunks of local tributaries. For example,
the Colorado River finished aggrading and had already begun incising before the main pulse of aggradation in the trunks of local
catchments during Marine Isotope Stage 3, and then tributary incision followed during the millennial-scale fluctuations of the last
glacial epoch, potentially concurrent with mainstem aggradation.
The mainstem record appears to broadly correlate with regional
paleoclimate and upstream geomorphic records and thus may
be responding to climatic-hydrologic changes in its mountain
headwaters, with aggradation beginning during full-glacial times
and continuing into subsequent interglacials. The contrasting
lag time in responses of the dryland catchments within Grand
Canyon may be largely a function of the weathering-limited nature of hillslope sediment supply. В© 2005 Elsevier Ltd. All rights
reserved.
1477 Development of an OSL chronology for Late Pleistocene channel belts in the lower Mississippi valley, USA
Rittenour T.M., Goble R.J. and Blum M.D. Quaternary Science
Reviews 2005 24/23-24 (2539-2554)
The broad alluvial valley of the lower Mississippi River contains
large channel belts for which age control has been limited by
the lack of organic material for radiocarbon dating and deposit
ages greater than the limit of radiocarbon. In order to produce
a detailed chronology of fluvial evolution, samples for optical
dating were collected from Late Pleistocene channel-belt deposits. Quartz sand was analyzed using the coarse-grained, singlealiquot regenerative-dose (SAR) technique. Samples showed
little evidence of partial bleaching, and optical ages are for the
most part consistent with the available radiocarbon and relative
age constraints. Optical ages range from 85 to 11 ka and, along
with geomorphic and stratigraphic relationships, indicate that
the Mississippi River was meandering during the end of the last
interglacial (85-83 ka) and switched to a braided regime by 64-50
ka during initial marine oxygen isotope stage (OIS) 4/3 glaciation
of the upper Mississippi drainage basin. The Mississippi River
switched back to a meandering regime after formation of the
youngest braid belt at 11 ka. The 69 optical ages presented here
provide the first detailed chronology of lower Mississippi valley
braid-belt and Pleistocene meander-belt formation, and provide
an example of the utility of optical dating in fluvial settings where
material for radiocarbon dating is scarce. В© 2005 Elsevier Ltd.
All rights reserved.
1478 Isotopic fractionation during leaching of impure carbonates and their effect on uranium series dating
Alcaraz Pelegrina J.M. and Martnez- Aguirre A. Quaternary
Science Reviews 2005 24/23-24 (2584-2593)
Experiments were designed to evaluate the behaviour of detritus
during the leaching of impure carbonates by applying the U-Th
isochron technique. We used one natural detritus and a pure,
well-dated CaCO3 , alone and in artificial mixtures. One set of
experiments was designed to study the effects of sample pretreatment on the detritus and a second set to examine the effect
of acid attacks on both the carbonate and the detritus fractions
in a mixture of constant proportions. For both sets of data,
the extracted fraction from the detritus was calculated for 238 U,
234 U, 230 Th and 232 Th and their constancy established. These
conditions are necessary to apply the L/L method [Schwarcz,
H.P., Latham, A.G., 1989. Dirty calcites. 1.-Uranium-series
dating of contaminated calcite using leachates alone. Chemical
Geology (Isotopes Geoscience Section) 80, 35-43] for U/Th dat-
280
THE QUATERNARY
ing. Finally, the L/L method was applied to the artificial impure
carbonate and the resulting age is found in agreement with the
age of the pure carbonate sample. We concluded that conditions
of the L/L method to be applied for ageing impure carbonates
hold. В© 2005 Elsevier Ltd. All rights reserved.
1479 In situ U-series dating by laser-ablation multi-collector
ICPMS: New prospects for Quaternary geochronology
Eggins S.M., GrВЁun R., McCulloch M.T. et al. Quaternary Science
Reviews 2005 24/23-24 (2523-2538)
The capabilities and potential applications of in situ dating of
Quaternary materials using laser ablation-MC-ICPMS are explored. 234 U/ 238 U and 230 Th/234 U can be measured with precision
sufficient for dating at a spatial resolution of 100 m or better in
samples that contain as a little as 1 ppm uranium. Moreover, U
and Th concentrations and U-series isotope ratios can be continuously profiled to determine changes in age that occur with sample
growth (e.g. in speleothems). These capabilities additionally
permit the dating of bones, teeth and possibly molluscs, which
are subject to post-mortem open-system behaviour of U-series
isotopes, and can be employed to elucidate processes of U-series
migration during weathering and diagenesis. A drawback of
laser ablation-MC-ICPMS is that it cannot in general provide
U-series age estimates with the high precision and accuracy of
conventional TIMS or solution MC-ICPMS methods. However,
sample preparation is straightforward, the amount of sample consumed negligible, and it can be used to rapidly characterise or
screen and select samples from which more precise and accurate
dates can be obtained using conventional methods. Given further instrumental developments and the establishment of suitable
matrix-matched standards for carbonates and other materials, we
foresee that laser ablation-MC-ICPMS will play an increasingly
important role in Quaternary dating research.
1480 A middle Pleistocene mollusc fauna from a borehole in
Northern Oberrheingrabens (Bohrung Mannheim-Lindenhof) (German) (Eine mittelpleistozВЁane Molluskenfauna aus
dem Oberen Zwischenhorizont des nВЁordlichen Oberrheingrabens (Bohrung Mannheim-Lindenhof))
RВЁahle W. Mainzer Geowissenschaftliche Mitteilungen 2005 -/33
(9-20)
Upper layer sediments from the so-called "Oberer Zwischenhorizont" obtained from boreholes in the Mannheim area of the Upper
Rhine Graben yielded quite a diverse mollusc fauna dating from
a Middle Pleistocene interglacial. The occurence of extinct taxa
like Parafossarulus crassitesta and Clausilia rugosa antiquitatis is
biostratigraphically important and so are the finds of molars of
an early representative of the vole Arvicola terrestris. Judging
from these fossil remains the age of the investigated section is
unlikely to be younger than Cromer-Interglacial IV (OIS 13),
yet not older than Cromer-Interglacial III (OIS 15). An Upper
Pleistocene age (Eemian) should, no doubt, be excluded.
1481 ESR dating of glacial tills and glaciations in the Urumqi
River headwaters, Tianshan Mountains, China
Zhao J., Zhou S., He Y. et al. Quaternary International 2005
144/1 (61-67)
Electron spin resonance (ESR) dating of the Shangwangfeng, the
Xiawangfeng, and the Gaowangfeng tills in the headwaters of the
Urumqi River was carried out using Ge centers in quartz grains.
The Shangwangfeng till is dated at 35 3.5 ka BP. Three dates
from the lower portion of the Xiawangfeng till are 171.1 17,
176 18, and 184.7 18 ka BP, respectively, and the age of the
Gaowangfeng till is 459.7 46 ka BP. Considering the available
ages (i.e. 14 C, TL and ESR) and the principles of geomorphology and stratigraphy, the Shangwangfeng till is determined to
be deposited in marine isotopic stage 2-3 (MIS2-3). The upper
part of the Xiawangfeng till was formed in MIS4 and the lower
part was deposited in MIS6. The Gaowangfang till is the oldest
at the head of the Urumqi River, corresponding to MIS12. The
age of the Gaowangfang till also demonstrates that the Tianshan
Mountains lay at a suitable altitude for a glacial climate at that
time, when the glaciers on this segment of the mountain began
to develop. В© 2005 Published by Elsevier Ltd.
Palaeoclimatology
1482 Pervasive and long-term forcing of Holocene river instability and flooding in Great Britain by centennial-scale
climate change
Macklin M.G., Johnstone E. and Lewin J. Holocene 2005 15/7
(937-943)
This paper presents the first probability-based record of flooding
in Europe that spans the entire Holocene. An analysis of 506 14 C
dated fluvial units collected across the whole of Great Britain
provides a novel and robust methodology for improving flood
risk assessment by geographically and temporally extending the
record of extreme flood events. Sixteen episodes of increased
flooding occurrence are identified, 12 of which (at c. 11 160,
5730, 4840, 4520, 3540, 2730, 2550, 2280, 1950, 1290, 660,
570, cal. BP) are recorded in most regions, whereas four phases
(at c. 6820, 5540, 1650, 860 cal. BP) affected some parts
of Great Britain more than others. In all regions large variations in flood frequency and magnitude occurred before forest
clearance and indicate an underlying climatic control. During
the mid-Holocene there is evidence for a hydroclimatic вЂ�system
switchвЂ™, which in terms of catchment hydrology in Great Britain
was marked by two sudden increases in both the frequency and
severity of floods at c. 5000 cal. BP and, most notably, at
c. 3000 cal. BP. The marked non-stationary behaviour of the
British flood series at these times reflects a regional hydrologic
response to large-scale ocean-atmospheric circulation changes
superimposed on a pattern reflecting both long-term land-use
change and the preferential preservation of later fluvial units.
Centennial-scale variations in the occurrence of extreme flood
events in Great Britain appear to be a sensitive indicator of past
and present climate change in the North Atlantic region. В© 2005
Edward Arnold (Publishers) Ltd.
1483 Holocene climate evolution in the high-latitude Southern Hemisphere simulated by a coupled atmosphere-sea iceocean-vegetation model
Renssen H., Goosse H., Fichefet T. et al. Holocene 2005 15/7
(951-964)
The Holocene climate is simulated in a 9000-yr-long transient
experiment performed with the ECBilt-CLIO-VECODE coupled
atmosphere-sea ice-ocean-vegetation model. This experiment is
forced with annually varying orbital parameters and atmospheric
concentrations of CO2 and CH 4 . The objective is to study the
impact of these long-term forcings on the surface temperature
evolution during different seasons in the high-latitude Southern
Hemisphere. We find in summer a thermal optimum in the midHolocene (6-3 ka BP), with temperatures locally 3В°C above the
preindustrial mean. In autumn the temperatures experienced a
long-term increase, particularly during the first few thousand
years. The opposite trend was simulated for winter and spring,
with a relatively warm Southern Ocean at 9 ka BP in winter (up
to 3.5В°C above the preindustrial mean) and a warm continent
in spring (+3В°C), followed by a gradual cooling towards the
present. These long-term temperature trends can be explained
by a combination of (1) a delayed response to orbital forcing,
with temperatures lagging insolation by 1 to 2 months owing to
the thermal inertia of the system, and (2) the long memory of the
Southern Ocean. This long memory is related to the storage of the
warm late winter-spring anomaly below the shallower summer
mixed layer until next winter. Sea ice plays an important role
as an amplifying factor through the ice-albedo and ice-insulation
feedbacks. Our experiments can help to improve our understanding of the Holocene signal in proxies. For instance, the results
suggest that, in contrast to recent propositions, teleconnections
to the Northern Hemisphere appear not necessarily to explain the
history of Southern Hemisphere temperature changes during the
Holocene. В© 2005 Edward Arnold (Publishers) Ltd.
1484 Ice caves as an indicator of winter climate evolution:
A case study from the Jura Mountains
Luetscher M., Jeannin P.- Y. and Haeberli W. Holocene 2005
15/7 (982-993)
Subsurface ice fillings were first described in the Jura Mountains
at the end of the sixteenth century. In order to assess the impact
THE QUATERNARY
of climate change on low-altitude cave ice a detailed inventory
has been drawn up and more than 50 objects have been identified.
Comparisons between older cave maps, photographic documents
and present-day observations outline a negative trend in ice mass
balances, a trend that increased at the end of the 1980s. As most
of these ice caves act as cold air traps, this negative mass balance
is mainly attributed to higher winter temperatures and to reduced
snow precipitation at low altitudes. The equilibrium line altitude
of ice caves is believed to have increased several hundred metres
between AD 1978 and 2004. Photographic comparisons and
proxy records in some of the caves studied provide evidence of
a rapid mass turnover. Ice ages range between less than a few
decades and a millennium. Climatic records in these ice fillings
will therefore present only short time series compared with other
cave sediments. However, indications of former ice fillings have
been found in different caves of the Jura Mountains and outline
their potential role as palaeoclimatic markers. В© 2005 Edward
Arnold (Publishers) Ltd.
1485 Vegetation and fire history since the Late Pleistocene
from the Trinity Mountains, northwestern California, USA
Daniels M.L., Anderson R.S. and Whitlock C. Holocene 2005
15/7 (1062-1071)
A 267-cm sediment core spanning the past c. 15 200 cal. yr
was recovered from Mumbo Lake, in the Trinity Mountains of
northwestern CaliforniaвЂ™s Klamath Region. Plant macrofossils
and pollen detail local and extra-local vegetation history, while
high-resolution charcoal analysis provides details on local fire
history. For the first c. 3000 years, climate was colder and
drier than present, and supported an open, subalpine parkland
vegetation, with low fire frequencies and fuel biomass. From
c. 12 100 to 9800 cal. yr BP increasing moisture and soil
development led to a woodland community with three new pine
species invading the basin. Fire frequencies remained low, but
individual fires may have been more intense because of increased
fuel loads. Between c. 9800 and 7200 cal. yr BP, climate
warmed and dried considerably, allowing for the expansion of
oak and other chaparral species. Fire frequencies increased in
the early Holocene, but low charcoal accumulation rates suggest
a frequent, relatively low-intensity fire regime. From c. 7200 to
3800 cal. yr BP, the climate became cooler and moister again.
Many conifer species appeared for the first time, although chaparral species maintained a strong presence. The fire record shows
a dramatic increase in charcoal accumulation rates as well as an
increase in fire frequency. From c. 3800 cal. yr BP to present,
more conifer species enter the record, and abundance of chaparral
species gradually diminishes to present levels. В© 2005 Edward
Arnold (Publishers) Ltd.
1486 Standardized precipitation index reconstructed from
Turkish tree-ring widths
Touchan R., Funkhouser G., Hughes M.K. and Erkan N. Climatic
Change 2005 72/3 (339-353)
May-July Standardized Precipitation Index (SPI) for the land area
of most of Turkey and some adjoining regions are reconstructed
from tree rings for the period 1251-1998. The reconstruction was
developed from principal components analysis (PCA) of four
Juniperus excelsa chronologies from southwestern and southcentral Turkey and is based on reliable and replicable statistical relationships between climate and tree ring growth. The
SPI reconstruction shows climate variability on both interannual
and interdecadal time scales. The longest period of consecutive
drought years in the reconstruction (SPI threshold -1) is 2 yr.
These occur in 1607-1608, 1675-1676, and 1907-1908. There
are five wet events (SPI threshold +1) of two consecutive years
each (1330-1331, 1428-1429, 1503-1504, 1629-1630, and 19131914). A 5-yr moving average of the reconstructed SPI shows
that two sustained drought periods occurred from the mid to late
1300s and the early to mid 1900s. Both episodes are characterized by low variability. В© Springer 2005.
1487 Vegetation changes during the past 1300 years in western equatorial Africa: A high-resolution pollen record from
Lake KamalВґetВґe, LopВґe Reserve, Central Gabon
Ngomanda A., Chepstow- Lusty A., Makaya M. et al. Holocene
2005 15/7 (1021-1031)
Vegetation changes during the past 1300 years are reconstructed
281
in western equatorial Africa using a high-resolution pollen record
from Lake KamalВґetВґe. This small marshy basin (c. 5-7 ha)
is located in forest-savanna mosaic in LopВґe Reserve (0В°43вЂ™S,
11В°46вЂ™E), central Gabon. The KamalВґetВґe pollen data show the
persistence over the past 1300 years of a relatively stable forestsavanna mosaic, associated with significant changes of the forest
component. Three successive stages of forest dynamics occurred.
First, at 1325 cal. BP, moist semi-evergreen rainforest existed
around the catchment of Lake KamalВґetВґe. However, it appears
from the consistent presence of > 70% Gramineae pollen that the
site was always primarily in savanna. Secondly, from c. 1240 to
550 cal BP, a noticeable increase in shade-intolerant plant species
indicate openings in the rainforest canopy. The persistence of
gap-colonizer species, such as Macaranga, Tetrorchidium and
Musanga for several centuries in the rainforest, is explained by
recurring canopy disturbance associated with shifts in available
moisture. These hydrological changes may be related to a succession of longer and more severe dry seasons than observed today.
Thirdly, at 550 cal BP, mature forest was re-established, corresponding to progressive savanna colonization by forest pioneer
species such as Aucoumea klaineana, Lophira alata and Fagara
macrophylla. This new phase of forest expansion coincided with
a marked lithological change, indicating an increase in lake-level.
It is concluded that the major vegetation changes observed are
due to climatic variability, and anthropogenic action had limited
influence. В© 2005 Edward Arnold (Publishers) Ltd.
1488 Complex speleothem growth processes revealed by
trace element mapping and scanning electron microscopy
of annual layers
Treble P.C., Chappell J. and Shelley J.M.G. Geochimica et Cosmochimica Acta 2005 69/20 (4855-4863)
Closely-spaced transects measured by excimer laser ablation inductively-coupled plasma mass spectrometry (ELA-ICPMS) at 5
and 32 m spatial resolution are used to generate trace element
composition maps (Ba, Sr, Mg, U, Na, P and Al) from MND-S1, a
previously studied modern stalagmite from southwest Australia
(Treble et al., 2003 1). Rainfall at the site is highly seasonal,
and trace elements in MND-S1 show strong seasonal variation.
Trace element maps show that Ba, Sr, U and Na concentrations
coherently follow annual growth layers identified from Scanning
Electron Microscopy (SEM) images. The SEM images also
reveal that stalagmite growth did not proceed uniformly: growth
layers vary in thickness and locally pinch out. Highly preferential crystal growth, determined by nucleation sites left by
the previous yearвЂ™s growth, may be responsible for this uneven
growth layering. Differential crystal growth apparently causes
variability of trace element concentrations along each annual
layer, although additional disequilibrium processes affect Mg,
which is less distinctly banded than Ba, Sr, U and Na. Uneven
and discontinuous growth layers influence the number of annual
cycles, their wavelengths and seasonal amplitudes measured in
any one transect. This has clear implications for studies that use
annual trace element cycles as chronological markers, growth
rate or seasonality proxies. Copyright В© 2005 Elsevier Ltd.
1489 Palaeoclimatology and palaeohydrography of the glacial stages on Celtic and Armorican margins over the last 360
000 yrs
Mojtahid M., Eynaud F., Zaragosi S. et al. Marine Geology 2005
224/1-4 (57-82)
Core MD03-2692 was retrieved in a water-depth of 4064 m on
the Celtic margin (Bay of Biscay) during the SEDICAR cruise
onboard the RV Marion Dufresne II. It covers the last 360 ka
in a total length of 39 m. Multidisciplinary analyses have been
applied to this sequence with the aim of studying the palaeoclimatic and palaeoenvironmental signals of the last few climatic
cycles. The analyses undertaken include: (1) non-destructive
logging with: physical properties (magnetic susceptibility, sediment colour), X-ray radiography and measurement of the major
elements by X-ray-fluorescence, (2) analyses of planktonic and
benthic foraminifera, lithic grains and stable isotopic measurements (oxygen and carbon). We have focused on the long-term
evolution of glacial stages (with special attention to terminations
and Heinrich events). The results obtained confirm the close correlation between deep-sea sedimentation recorded on the Celtic
282
THE QUATERNARY
margin and changes in the terrestrial environment of the adjacent
continent. Heinrich layers have been identified in MIS 2, 3, 6 and
8. We note the occurrence of laminated facies within deglacial
sequences deposited during Termination I and MIS 6. These facies are closely linked to disintegration phases of the British-Irish
Ice Sheet (BIS). The laminations contain lower ice-rafted detritus
(IRD) concentrations than the equivalent Heinrich layers and are
linked to abrupt changes in sea-surface palaeotemperatures. We
suggest that the laminations are formed by an annual cycle of
meltwater and iceberg release from the disintegrating BIS generating cascading plumes of dense turbid meltwater coeval with
IRD release. В© 2005 Elsevier B.V. All rights reserved.
1490 Last interglacial atmospheric CO2 changes from
stomatal index data and their relation to climate variations
Rundgren M., BjВЁorck S. and Hammarlund D. Global and Planetary Change 2005 49/1-2 (47-62)
A high-resolution atmospheric CO2 reconstruction based on
stomatal index data obtained from Betula and Quercus leaf fragments extracted from the Danish Hollerup lake sediment section
provides a unique insight into last interglacial CO2 dynamics.
According to pollen stratigraphic correlations the CO2 record
covers the first c. 7400 years of the Eemian, as palaeobotanically
defined in northwestern Europe. The first c. 3000 years of the
reconstruction are characterised by centennial to millennial CO2
variability in the interval 250-290 ppmv, while the remaining part
of the record is generally more stable with slightly higher values
(290-300 ppmv). According to pollen stratigraphic correlations
this shift in CO 2 dynamics is coincident with the end of the early
Eemian climatic optimum in northwestern Europe. Pollen data
from this region indicate that early Eemian CO2 instability may be
linked to vegetation succession following deglaciation in Europe,
but vegetation dynamics on other northern continents were probably also important. In addition, palaeoceanographic records
from the Nordic seas indicate an influence of oceanic processes
on the reconstructed Eemian CO2 evolution. A 300-year period
of rapid CO2 oscillations immediately before the establishment
of stable conditions is synchronous with a dry and cool event
previously inferred from proxy data from the same sediment
sequence, suggesting that this was a climatic event of regional
or global significance. The presented CO2 reconstruction is in
general agreement with previous ice core and stomatal-based
CO2 data, although a larger variability compared with Vostok ice
core data is evident. This may be explained partly by the different
resolution of the two records and the inherent smoothing of ice
core gas records. В© 2005 Elsevier B.V. All rights reserved.
1491 Mid-Holocene strengthening of the Southern Westerlies in South America - Sedimentological evidences from Lago
Cardiel, Argentina (49В°S)
Gilli A., Ariztegui D., Anselmetti F.S. et al. Global and Planetary
Change 2005 49/1-2 (75-93)
The paleoclimatic evolution of southern South America is characterized to a large extent by the behavior (strength and latitudinal
position) of the storm tracks of the Southern Westerlies. Our
study site, Lago Cardiel (49В°S), lies within the modern influence
of the Southern Westerlies and, therefore, is ideally located to
track the past migrations of these storm tracks. With a coring
strategy taking into account the lateral differences in sedimentation and an excellent core-to-core correlation using tephra layers,
a composite sedimentological record of almost 25 m was established covering the last 16,000 cal yr. Sedimentological and
petrophysical analysis of the cores revealed the establishment of
a dominant lake current since 6800 cal yr BP leading to a drift
deposition, which is especially well-expressed in the sedimentary record by an increase in magnetic susceptibility values. As
this pattern of currents is most likely induced by wind activity,
we propose that the observed increase in magnetic susceptibility documents an intensification of the westerly storm tracks.
This intensification occurred slightly earlier than previously suggested based on palynological evidence. The strengthening in
the Southern Westerlies during the mid-Holocene is most likely
caused by an increase in the temperature gradient as a result of
enhanced influence and/or southward migration of the Southeast
Pacific anticyclone and a larger Antarctic sea-ice extent. В© 2005
Elsevier B.V. All rights reserved.
1492 Late Pleistocene vegetation of the basin of Phlious,
NE-Peloponnese, Greece
Urban B. and Fuchs M. Review of Palaeobotany and Palynology
2005 137/1-2 (15-29)
Results of sedimentological and palynological analyses and 14 C
dating of organic lake sediments of a transect through the basin
of Phlious, west-southwest of Corinth (NE-Peloponnese, Greece)
are presented. They provide a record of five moist and temperate phases, rich in predominantly deciduous Quercus and Pinus
with minor representation of other deciduous and evergreen trees
including evergreen oak and shrubs, interrupted by five drier
and cooler episodes including Heinrich event (HE) 5, during a
period of relatively high but fluctuating lake levels within Marine Isotope Stage 3 (MIS 3). The youngest interstadial of the
Pleistocene pollen sequence is correlated with GRIP Greenland
Interstadial 9 (GI9) with a calibrated age of around 40,000 years
BP (14 C 34,440 yrs BP). In the uppermost part of the Pleistocene
sequence the occurrence of HE 4 is rather probable. This initial
Pleistocene record from southern Greece is compared with those
from central Greece to provide a regional synthesis of vegetation
and climatic variation during this part of the last glacial period.
В© 2005 Elsevier B.V. All rights reserved.
1493 Pre-industrial metal anomalies in ice cores: A simplified reassessment of windborne soil dust contribution and
volcanic activity during the last glaciation
Oyarzun R., Lillo J., SВґanchez- HernВґandez J.C. and Higueras P.
International Geology Review 2005 47/11 (1120-1130)
A major issue regarding pre-industrial accumulation of heavy
metals such as Cu, Ph, Zn, or Hg in ice cores relates to the
source(s) of the metals. We investigate the two possibilities that
have been generally advocated for the origin of metal anomalies:
(1) increased amounts of windborne dust during particularly cold
periods; and (2) volcanic activity. We analyze the time span
35,000-14,000 yrs BP, which is characterized by extreme temperature deviations ( T;-2.1В° to -9.8В°C). Our findings show no
definitive relationships between climate, dust, and metal contents, at least during the colder episodes. Thus, although dust
deposition undoubtedly adds metals to the ice, it not clear whether
climate can fully account for a direct relationship between these
variables. In order to study the volcanic hypothesis, we analyze
the case under a double perspective: (1) large explosive episodes related to acid magmatism; and (2) quieter mafic volcanic
activity. Although the first one can introduce huge volumes of
metal-rich aerosols to the stratosphere during single, catastrophic
events, the latter is more continuous, accumulative, and far richer
in sulfur. However, inasmuch as metals build volatile species
with sulfur and halides, the chloride-rich character of the acid
volcanism could easily compensate for its deficiency in sulfur.
Thus, we suggest that the volcanic activity, via quiescent degassing and eruptive episodes, may account for an important part of
the heavy metal contents present in the ice cores. Copyright В©
2005 by V. H. Winston & Son, Inc. All rights reserved.
1494 Oxygen isotopic evidence for greater seasonality in
Holocene shells of Donax variabilis from Florida
Jones D.S., Quitmyer I.R. and Andrus C.F.T. Palaeogeography,
Palaeoclimatology, Palaeoecology 2005 228/1-2 (96-108)
Donax variabilis, the variable coquina clam, has been a common
inhabitant of exposed sandy beach intertidal and shallow subtidal
zones in the southeastern United States throughout the Pleistocene and Holocene. It is ideally suited for paleotemperature
studies because it is restricted to environments of well-mixed,
normal-marine seawater with a fairly uniform isotopic composition. As a result, oxygen isotopic variability in D. variabilis
shells is largely explained by temperature variation. Although
D. variabilis is small and short-lived, its shell represents an important paleoclimate archive because of its unique habitat preference. High-resolution sampling of individual D. variabilis shells
and comparison of oxygen isotopic temperature profiles with
historical seawater temperatures from the northeastern Florida
coast indicate rapid shell growth over a brief life span of three
to five or six months. Analysis of two modern shells reveals
a close correspondence between isotopically determined water
temperatures and historical water temperatures during the springsummer growing season. Paleotemperature profiles from four
THE QUATERNARY
archaeological shells, however, suggest a longer growth interval spanning summer-autumn. Two Preceramic Archaic Period
shells (ca. 4240 and 5570 14 C yr BP) and two Orange Period
Archaic shells (ca. 3600 and 3760 14 C yr BP), from four different
archaeological sites, yield paleotemperatures that average 3.5В°C
higher than present summer-autumn water temperatures. These
warm paleotemperatures highlight seasonality differences associated with the mid-Holocene Hypsithermal climatic interval in
this region. В© 2005 Elsevier B.V. All rights reserved.
1495 Climate records from a bivalved Methuselah (Arctica
islandica, Mollusca; Iceland)
SchВЁone B.R., Fiebig J., Pfeiffer M. et al. Palaeogeography,
Palaeoclimatology, Palaeoecology 2005 228/1-2 (130-148)
We measured annual shell growth rates of a 374-year-old (radiometrically confirmed) bivalve mollusk specimen of Arctica
islandica (Linnaeus). This bivalve represents the oldest ever
reported individual animal. In addition, we analyzed 1051 individual powder samples from ontogenetic years two to 40 (=
80% of the entire shell height) for isotope analyses. Oxygen and
carbon isotopes exhibit clear intra-annual cycles. The highest
measured carbon isotope values (on average + 2.73вЂ°) occurred
during summer, i.e., during maximum primary productivity. The
18 Oaragonite -derived temperature time-series cover the period of
AD 1496-1533. Temperatures calculated from oxygen isotopes
ranged from 4.5 to 9.3В°C and exhibit a mean value of 6.2В°C. The
latter coincides well with the 1854-2003 mean value of 6.81В°C
for sea-surface temperature between February and September (=
growing season of A. islandica). Neither oxygen nor carbon
isotopes exhibit age-related, unidirectional trends. However,
13 Caragonite and 18 Oaragonite values fluctuated at decadal periods
of four, six and eight to nine years (NAO-type periods) as well as
12-14 years which may represent teleconnections to cycles in the
tropical Atlantic. Annual shell growth is positively correlated to
intra-annual 18 O aragonite minima, i.e., warm summer temperatures (R2 = 0.34), and to intra-annual 13 Caragonite minima (higher
food supply; R2 = 0.42). Using a linear multiregression model,
65% of the variation in annual shell growth can be explained
by summer temperature and food supply. The formation of extremely narrow annual increments coincides with major volcanic
eruptions (e.g., Tambora 1815). A period of extremely variable
growth occurred during the culmination of the Little Ice Age in
Iceland between ca. AD 1550 and 1620. Shell growth during
AD 1765-1780, however, was characterized by very little year-toyear variability, probably as the result of extremely mild climate
near the end of the Little Ice Age. This study demonstrates
that shells of A. islandica provide subseasonal to multidecadal,
precisely dated multi-proxies of environmental variables from
marine, mid to high latitudes. Such data can be used to validate
and complement climate models and further assess human impact on climate and ecosystems. В© 2005 Elsevier B.V. All rights
reserved.
1496 Preserving low-frequency climate signals in growth
records of geoduck clams (Panopea abrupta)
Strom A., Francis R.C., Mantua N.J. et al. Palaeogeography,
Palaeoclimatology, Palaeoecology 2005 228/1-2 (167-178)
The capacity of geoduck clams (Panopea abrupta) to preserve
detailed records of climatic change in their shells is limited primarily by longevity. Unlike the multi-centennial growth records
commonly available from trees, shells rarely yield more than 160
years of data; consequently low-frequency signals may be lost
when band width series are processed. Here we investigate use
of вЂ�Regional Curve StandardizationвЂ™ (RCS) to preserve decadal
to centennial-scale growth trends in the relatively short segment
lengths available from individual clams. Advantages of this
method over the more common вЂ�exponentialвЂ™ treatment are first
explored through simulation experiments using sine waves embedded in geoduck growth curves. Both standardization methods
are then used to remove biological trends from growth records
of geoduck shells sampled near Protection Island, in the Strait
of Juan de Fuca. The resulting chronologies are compared in
terms of their spectral properties, their correlations with historical air temperature records and their agreement with historical
observations of the marine environment. Simulation experiments
illustrated the potential benefits of using the RCS growth model
to standardize shell growth series, but empirical results were
283
inconclusive. The RCS chronology exhibited enhanced spectral power at periods exceeding the length of growth segments,
and provided stronger correlation with coastal air-temperature
records, especially during the earliest portion of the chronology.
Over the full period of comparison, however, the correlation coefficients were essentially identical. Observational data from the
mid to late 1800s appears to support the RCS results. Northward
range expansions of several marine fish species coincide with
a period of conspicuously high values in the RCS chronology,
and suggest that the coastal ocean was unusually warm along
western North America from the 1850s through the 1870s. В©
2005 Elsevier B.V. All rights reserved.
1497 Oxygen isotope composition of modern and archaeological otoliths from the estuarine hardhead catfish (Ariopsis
felis) and their potential to record low-latitude climate change
Surge D. and Walker K.J. Palaeogeography, Palaeoclimatology,
Palaeoecology 2005 228/1-2 (179-191)
Shells and otoliths (fish "ear bones") from archaeological deposits of Pine Island, southwest Florida, provide valuable archives
of ecological patterns, climate change, and associated human
responses. Many remains from these deposits that can be used
for climate reconstruction are from estuarine animals. The challenge in using oxygen isotope composition of their carbonate hard
parts lies in deconvoluting the effects of temperature and salinity
(mixing of fresh- and saltwater, each having different isotopic
compositions). Otoliths of the hardhead catfish (Ariopsis felis,
Linneaus, 1766) may provide a record of winter temperature
without the complication of salinity variation because this fish
spends winter months in waters of marine to near-marine salinities. Hence, 18 OWATER can be constrained when employing
published temperature equations. Here, we present geochemical data from modern and archaeological otoliths to evaluate
whether they preserve winter temperature. A modern catfish was
caught near Pine Island Sound and the otoliths (lapilli) removed.
Archaeological otoliths from the 2nd/3rd century AD, falling
within the Roman Optimum (RO), and the 13th/14th century
AD, falling within the Little Ice Age (LIA), were obtained from
the Florida MuseumвЂ™s collections. Oxygen isotope compositions
were converted to temperature using published temperature equations and assuming + 1вЂ° for Gulf water. Isotopic compositions
for the modern otolith range from -3.55вЂ° to + 0.29вЂ°, the LIA
otolith ranges from -3.92вЂ° to + 0.52вЂ°, and the RO otolith
ranges from -1.80вЂ° to + 0.84вЂ°. All three otoliths record winter
temperature ( 20В°C) similar to modern conditions. Calculated
summer temperatures for the modern and LIA otoliths ( 40В°C)
are overestimated and reflect the combined influence of temperature and salinity when catfish inhabit brackish estuarine waters
during their reproductive season. In contrast, summer temperature estimates for the RO otolith are similar to modern conditions
indicating estuarine water during the summer was close to + 1вЂ°.
This result suggests that seasonal rainfall patterns during the time
period represented by the RO otolith were different than today,
such that the summer wet season was not prevalent. В© 2005
Elsevier B.V. All rights reserved.
1498 Denitrification under glacial and interglacial conditions: A physical approach
Meissner K.J., Galbraith E.D. and VВЁolker C. Paleoceanography
2005 20/3 (1-13)
Recent analysis of sedimentary 15 N records over the last 200,000
years has shown an expansion of water column denitrification
zones during warmer periods and a shrinkage of these oxygenpoor regions during glacial periods. Two different mechanisms
could be responsible for driving the changes in the denitrification
records: variations in local productivity leading to a change in
remineralization rates and/or changes in the ocean circulation and
ocean temperature resulting in variations of the physical supply
of dissolved oxygen. Here we focus on the "supply" mechanism by using a fully coupled atmosphere-ocean-sea ice-land
surface scheme model (the University of Victoria Earth System
Climate Model) to examine oxygen supply under varying physical conditions while maintaining an invariant biological oxygen
utilization scheme. We show that circulation changes can be
the cause for the observed changes in dissolved oxygen in the
glacial ocean. Lower temperatures and enhanced formation of
Antarctic Intermediate Water and North Pacific Intermediate Wa-
284
THE QUATERNARY
ter during glacial periods increase the physical supply of oxygen
and therefore decrease water column denitrification. In our Last
Glacial Maximum simulations the change in water characteristics in the eastern tropical Pacific is important enough to reduce
denitrification by 46% to 65% compared to present-day conditions, depending on the wind fields used as boundary conditions.
The consequences of our findings could be substantial for the
near future. With a warming climate, denitrification zones could
expand, leading to changes in the biological pump and the flux
of N2 O into the atmosphere. Copyright 2005 by the American
Geophysical Union.
1499 Palaeoenvironmental changes in southern Patagonia
during the last millennium recorded in lake sediments from
Laguna Azul (Argentina)
Mayr C., Fey M., Haberzettl T. et al. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/3-4 (203-227)
Marked environmental changes in the southern Patagonian steppe
during the last 1100 years are detected by a multi-proxy study
of radiocarbon-dated sediment cores from the crater lake Laguna
Azul (52В°05 S, 69В°35 W). A prominent shift in carbon isotope
records occurred between AD 1670 and AD 1890 induced by a
change to cooler climate conditions with a concurrent lake level
rise. A second perturbation of the lake ecosystem started with a
fire event around AD 1830. The fire event triggered increased soil
erosion initiating a change of the diatom assemblages. This shift
in diatom assemblages may have been enhanced by shrinkage
of littoral habitats and higher nutrient supply in the course of
permanent European settlement at the end of the 19th century.
The introduction of neophytes by European sheep farmers is
confirmed by the permanent occurrence of Rumex pollen in the
sediment record since the beginning of the 20th century. В© 2005
Elsevier B.V. All rights reserved.
1500 The loess record from the section at Kurtak in Middle
Siberia
Frechen M., Zander A., Zykina V. and Boenigk W. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/3-4 (228-244)
Loess, loess-like sediments and the intercalated palaeosols along
the bluffs of the river Yenisei provide a detailed Upper Pleistocene climate archive for the southern part of Middle Siberia.
The section at Kurtak is one of the most detailed loess/palaeosol
sequences in Middle Siberia. Two major periods of sediment accumulation were recorded in the sequence: the stratigraphically
oldest one post-dating the last interglacial palaeosol and pre-dating the Kurtak Pedocomplex (oxygen isotope stage (OIS) 3); the
younger one post-dating the Kurtak Pedocomplex and predating
the Holocene soil. Three major phases of soil formation occurred
during the Upper Pleistocene. The Kameny Log Pedocomplex
(OIS 5e) consists of at least two pedogenetic episodes, a lower
clayey chernozem forming during a more humid and warmer
climate than today, and an upper chernozem representing a drier
climate than today, the latter one including a well-pronounced
carbonate-rich horizon. The Sukhoy Log Pedocomplex consists
of a chernozem-like palaeosol and two kastanozjems (OIS 5ca) and the Kurtak pedocomplex (OIS 3) with two chernozemlike palaeosols and up to three humic-rich layers. Additionally,
weakly developed gleyed horizons are considered to represent
palaeohydrological groundwater high levels. The results indicate
a synchronous evolution of climate and environment change in
both the more oceanic driven climate of West and Central Europe
and Middle Siberia, as evidenced by luminescence dating results.
В© 2005 Elsevier B.V. All rights reserved.
1501 Temperature variations since the mid-18th century for
western Nepal, as reconstructed from tree-ring width and
density of Abies spectabilis
Sano M., Furuta F., Kobayashi O. and Sweda T. Dendrochronologia 2005 23/2 (83-92)
The climate of western Nepal was reconstructed for the past 249
years using ring width and wood density of Abies spectabilis
(D. Don) Spach from western Nepal. A total of 46 increment
core samples were collected from 23 individual trees growing
in an open A. spectabilis stand near timberline of 3850 m a.s.l.
in Humla District, western Nepal. The core samples were subjected to densitometric analysis to obtain chronologies of ring
width and three kinds of intra-annual bulk densities, i.e., min-
imum, maximum, and mean. Response analysis of tree-ring
parameters with climate records revealed that the ring width
was correlated negatively with March-May (pre-monsoon) temperature and positively with March-May precipitation, while the
minimum density was correlated positively with March-July temperature and negatively with March-May precipitation. On the
other hand, the maximum and mean densities were positively
correlated with August-September and March-September temperatures, respectively. These results indicate that the ring width
and minimum density are primarily controlled by the pre-monsoon temperature and precipitation, while the latewood density
by the late monsoon temperature. Finally based on these results
of the response analysis, a transfer function was established, with
which March-September temperature was reconstructed for the
past 249 years, which shows a warming trend from 1750s until
approximately 1790, followed by cooling until 1810, then by a
gradual warming trend extending to 1950, and a notable cold
period continuing up to the present. No evidence of a consistent
warming trend over the last century or two commonly appearing
in higher latitudes was found in the present reconstruction, but
possible factor behind the widespread glacial retreat in the Nepal
Himalayas was discussed. В© 2005 Elsevier GmbH. All rights
reserved.
1502 Sediment sources and East Asian monsoon intensity
over the last 450 ky. Mineralogical and geochemical investigations on South China Sea sediments
Boulay S., Colin C., Trentesaux A. et al. Palaeogeography,
Palaeoclimatology, Palaeoecology 2005 228/3-4 (260-277)
A coupled approach based on clay mineral assemblages and isotopic data (Sr and Nd) of sediment from Ocean Drilling Program
(ODP) Site 1145 has been used to trace the sources of sediment
feeding the northern part of the South China Sea, and to investigate the evolution of East Asian monsoon intensity over the
last 450 ky. Clay mineral assemblages are dominated by illite
and smectite, with lesser abundance of chlorite and kaolinite.
87 Sr / 86 Sr and
Nd (0) isotopic data, combined with the smectite
/ (illite + chlorite) ratio, indicate that the Pearl River is the main
contributor for detrital material to the northern margin of the
SCS, with variable continental input of volcanic material derived
from the erosion of the Luzon Arc. These inputs follow the lowlatitude solar insolation with a 23 ky periodicity, as recorded by
a periodic change of the clay mineralogy. For the first time, this
study presents a SCS deep-sea sediment high-resolution record of
climatic changes in the last 450 ky, showing that smectite / (illite
+ chlorite) variations are mainly related to changes in the East
Asian summer monsoon intensity. Because the mineralogical
record is independent of other external forcing phenomena such
as global glacial/interglacial oscillations, the smectite / (illite +
chlorite) ratio has been used here as a proxy to reconstruct past
changes of the South-East Asian summer monsoon intensity. В©
2005 Elsevier B.V. All rights reserved.
1503 Did tree-Betula, Pinus and Picea survive the last glaciation along the west coast of Norway? A review of the
evidence, in light of Kullman (2002)
Birks H.H., Larsen E. and Birks H.J.B. Journal of Biogeography
2005 32/8 (1461-1471)
Aim: We discuss the hypotheses proposed by Kullman [GeoВЁ
Oko
21 (2000) 141; Nordic Journal of Botany 21 (2001) 39;
Journal of Biogeography 29 (2002) 1117] on the basis of radiocarbon-dated megafossils of late-glacial age from the central
Swedish mountains that boreal trees survived the glaciation along
the south-west coast of Norway and subsequently migrated eastward early in the late-glacial to early deglaciated parts of the
central Swedish Scandes mountains. Methods: We assess these
hypotheses on the basis of glacial geological evidence and four
lines of palaeoecological evidence, namely macro fossil records
of the tree species, vegetation and climate reconstructions from
plant evidence, independent climate reconstructions from other
proxies for the late-glacial environment of south-west Norway,
and the patterns of post-glacial spread of the tree species. Location: South and west Norway, central Swedish Scandes mountains (JВЁamtland). Results and conclusions: South-west Norway
and the adjacent continental shelf were under ice at the last-glacial maximum (LGM). The late-glacial vegetation of south-west
THE QUATERNARY
Norway was treeless and summer temperatures were below the
thermal limits for Betula pubescens Ehrh., Pinus sylvestris L. and
Picea abies (L.) Karst. Instead of spreading immediately after
the onset of Holocene warming, as might have been expected if
local populations were surviving, B. pubescens showed a lag of
local arrival of 600 to > 1000 years, Pinus lagged by 1500 to
> 2000 years, and Picea only reached southern Norway c. 1500
years ago and has not colonized most of south-west Norway
west of the watershed. Glacial geological evidence shows the
presence of an ice sheet in the Scandes at the LGM and in the
Younger Dryas, which was cold-based near or at the area where
the late-glacial-dated megafossils were recovered by Kullman.
We conclude that the samples dated by Kullman (2002) should
be evaluated carefully for possible sources of contamination. All
the available evidence shows that the biogeographical hypotheses, based on these radiocarbon dates taken at face value, of
late-glacial tree survival at the Norwegian coast and subsequent
eastwards spread to the mountains, are unsupportable. В© 2005
Blackwell Publishing Ltd.
1504 Temperatures of the habitat of quaternary mollusks
from Azerbaijan as determined from the Ca/Mg ratio
Aliyev S.A. and Sari A. Geochemistry International 2005 43/9
(920-927)
This study focuses on the characterization of calcium and magnesium distribution in the shells of Quaternary mollusks from
Azerbaijan and paleotemperature estimates from the Ca/Mg ratio.
Using the obtained paleotemperature values, three stages of temperature maximum were distinguished in the Quaternary period:
Holocene (19.9-24.3В°C), early Khvalyn (19.6-24.4В°C), and early
Khazar (19.3-22.2В°C); and two stages of cooling: late Khvalyn
(13.5-15.7В°C) and late Khazar (15.9-17.2В°C), corresponding to
the glacial and interglacial epochs of the late Pleistocene. The
obtained temperatures of the marine habitat and sedimentation in
the Caspian Sea (from the Ca/Mg ratio) were compared with temperature data for the eastern Mediterranean Sea determined by
various methods. The reported calcium-magnesium paleotemperatures are in agreement with the paleotemperature estimates
obtained by the investigation of the species composition of various systematic groups of planktonic foraminifera and 18 O in
the Late Quaternary basins of the eastern Mediterranean Sea
(including the Sea of Marmara). These data provide an adequate
record of variations in the temperature conditions of the habitat of
Caspian mollusks of Azerbaijan in Quaternary time. Copyright
В© 2005 by MAIK "Nauka/ Interperiodica" (Russia).
1505 Lateglacial palaeoenvironments and palaeoclimates
from Conty and Houdancourt, northern France, reconstructed from Beetle remains
Ponel P., Coope R., Antoine P. et al. Quaternary Science Reviews
2005 24/23-24 (2449-2465)
Two Lateglacial insect sequences are described (a) from Conty,
in the Selle valley and (b) from Houdancourt in the Oise valley,
both in northern France. These investigations are part of a multidisciplinary investigation involving archaeology, sedimentology, geomorphology, geochronology and palaeontology (pollen,
macroscopic plant remains, vertebrates, molluscs and insect fossils). The sequences of insect assemblages date from the latter
part of the BГёlling to the end of the AllerГёd periods. Environmental analysis of these faunas shows that rivers with riffles and
pools meandered across flood plains. The river was extensively
fringed with reedy vegetation. The only trees growing close to
the river were of Salix and/or Populus. All the insect assemblages
indicate that the thermal climates during the BГёlling and AllerГёd
periods were similar to one another and during both periods were
very nearly as warm as that of the present day. No insect fossils
were recovered from the sediments attributed to the Older Dryas
interval though other evidence from these sites suggests that this
event was decidedly colder than those immediately preceding
and succeeding it. Comparisons are made between Lateglacial
climatic patterns in northern France with those elsewhere in Europe. В© 2005 Elsevier Ltd. All rights reserved.
285
1506 A review of Late Pleistocene and Holocene biogeography of highland Mediterranean pines (Pinus type sylvestris)
in Portugal, based on wood charcoal
Figueiral I. and Carcaillet C. Quaternary Science Reviews 2005
24/23-24 (2466-2476)
The historical biogeography of highland Mediterranean pines is
explored based on Late Pleistocene and Holocene charcoal from
Portugal (Iberian Peninsula, SW Europe). The earliest presence
of Pinus type sylvestris (including P. nigra, P. sylvestris and P.
uncinata) is recorded in archaeological layers dated at ca 23,900
BP, during the Full Glacial. The abundance of remains identified
as Pinus type sylvestris suggests that this was a frequent taxon, at
least at middle altitudes. Significant occurrences were recorded
up until ca 11,000 BP, at the end of the Lateglacial warming
period. From the early Holocene onwards the presence of Pinus
type sylvestris is recorded only sporadically, but at least up to
2000 years ago. The competition with other tree and shrub
species favoured by the Holocene warming may have triggered
the decline of highland pines in Portugal. Eventual anthropogenic
impact is also considered as playing a role in its regional decline,
such as increasing fire frequency resulting from amplified land
use since the Neolithic. В© 2005 Elsevier Ltd. All rights reserved.
1507 Shallow-marine sediment cores record climate variability and earthquake activity off Lisbon (Portugal) for the
last 2000 years
Abrantes F., Lebreiro S., Rodrigues T. et al. Quaternary Science
Reviews 2005 24/23-24 (2477-2494)
Sea Surface Temperature (SST), river discharge and biological
productivity have been reconstructed from a multi-proxy study
of a high-temporal-resolution sedimentary sequence recovered
from the Tagus deposition center off Lisbon (Portugal) for the
last 2000 years. SST shows 2В°C variability on a century scale that
allows the identification of the Medieval Warm Period (MWP)
and the Little Ice Age (LIA). High Iron (Fe) and fine-sediment
deposition accompanied by high n-alkane concentrations and
presence of freshwater diatoms during the LIA (1300-1900 AD)
(Science 292 (2001) 662) suggest augmented river discharge,
whereas higher total-alkenone concentrations point to increased
river-induced productivity. During the MWP (550-1300 AD)
(Science 292 (2001) 662) larger mean-grain size and low values
of magnetic susceptibility, and concentrations of Fe, n-alkanes,
and n-alcohols are interpreted to reflect decreased runoff. At
the same time, increased benthic and planktonic foraminifera
abundances and presence of upwelling related diatoms point to
increased oceanic productivity. On the basis of the excellent
match found between the negative phases of the North Atlantic
Oscillation (NAO) index and the intensified Tagus River discharge observed for the last century, it is hypothesized that the
increased influx of terrigenous material during the LIA reflects
a negative NAO-like state or the occurrence of frequent extreme
NAO minima. During the milder few centuries of the MWP,
stronger coastal upwelling conditions are attributed to a persistent, positive NAO-like state or the frequent occurrence of
extreme NAO maxima. The peak in magnetic susceptibility,
centered at 90 cm composite core depth (ccd), is interpreted as
the result of the well-known 1755 AD Lisbon earthquake. The
Lisbon earthquake and accompanying tsunami are estimated to
have caused the loss of 39 cm of sediment (355 years of record
- most of the LIA) and the instantaneous deposition of a 19-cm
sediment bed. В© 2004 Elsevier Ltd. All rights reserved.
1508 Moving front or population expansion: How did Picea
abies (L.) Karst. become frequent in central Sweden?
Giesecke T. Quaternary Science Reviews 2005 24/23-24 (24952509)
The Holocene increase in Picea abies around four central Swedish
lakes was analysed using extended pollen counts over the sections
comprising the tail of frequent, but discontinuous, occurrences
and the beginning of the continuous curve. Simple landscape
scenarios were simulated to test possible mechanisms of the
spread and population expansion of P. abies in Scandinavia. Predicted patterns of pollen accumulation rates from the landscape
scenarios were compared to patterns observed at the four sites to
explore how the observed curves could have come about. Simulations of a moving front scenario indicate that pollen accumulation
286
THE QUATERNARY
rates should rise faster than the exponential and logistic increase
observed at the four sites. Exponential increase of pollen values
at the sites is most likely due to locally increasing populations.
However, the geography of expanding populations may influence
the shape of the curve. Empirical and model results are discussed
to gain new insights into the pattern and processes of the spread
of P abies in central Sweden. Propagule pressure and self-fertilisation are considered as possible explanations of why small
outpost populations that may have existed before the regional
expansion of P. abies did not expand earlier. В© 2005 Elsevier
Ltd. All rights reserved.
1509 The dynamics of chironomid assemblages and vegetation during the Late Quaternary at Laguna Facil, Chonos
Archipelago, southern Chile
Massaferro J., Brooks S.J. and Haberle S.G. Quaternary Science
Reviews 2005 24/23-24 (2510-2522)
We compare high-resolution pollen and chironomid records from
the last 15,000 yr in Laguna Facil, southern Chile. Major vegetation and chironomid changes are recorded between ca 14,900 and
14,700 cal. yr BP. During the Lateglacial, changes in the chironomid stratigraphy lag behind changes in the pollen stratigraphy
suggesting that the chironomids are responding to changes in the
tree canopy or in soil chemistry brought about by vegetational
development. At about 7200 cal. yr BP there is a change in the
chironomid stratigraphy in advance of changes in the vegetation.
This suggests that the response is to regional climatic change.
The relatively close correlation of the chironomid and pollen
stratigraphies with changes in charcoal concentrations also implicates the importance of fire and/or vulcanism in influencing
the dynamics of forest and limnological systems. There is no
clear evidence of cooling during the Younger Dryas chronozone
in Laguna Facil. В© 2005 Elsevier Ltd. All rights reserved.
1510 Synchrony of Southern Hemisphere Late Pleistocene
arid episodes: A review of luminescence chronologies from
arid aeolian landscapes south of the Equator
Munyikwa K. Quaternary Science Reviews 2005 24/23-24 (25552583)
Luminescence-dating chronologies that have been reported in
various studies of Late Pleistocene arid-land aeolian sequences
from Australia, southern Africa and South America are reviewed
with the objective of determining whether any pan-hemispheric
synchroneity existed in the timing of landscape responses to Late
Quaternary climate changes south of the equator. The results
broadly show that contemporaneous regional arid-land aeolian
activity occurred in Australia and southern Africa during the
periods ca 65-41 and 36-9 ka. The relatively limited luminescence data from the South American subcontinent also point to
recurrent arid-land aeolian deposition between 63 and 8 ka, with
increasing frequency in the period ca 32-8 ka. Records from
all three continents suggest a period of reduced aeolian activity
between 41 and 36 ka. Overall, the data are indicative of extensive landscape instability of the low to mid-latitudes in the
Southern Hemisphere during the last glacial period, particularly
at the Last Glacial Maximum, which accords with mainstream
opinions. Aeolian activity during the Holocene has generally
been localised. The rigour with which comparisons can be made
between the different studies, however, is constrained by variations in practices between laboratories and changes that have
occurred to luminescence dating procedures over the years. В©
2005 Elsevier Ltd. All rights reserved.
1511 Climatic and environmental changes at southeastern
coast of Lake Biwa over past 3000 years, inferred from borehole temperature data
Goto S., Hamamoto H. and Yamano M. Physics of the Earth and
Planetary Interiors 2005 152/4 (314-325)
In order to infer past climatic change in central Japan, we measured temperatures in a borehole at the Karasuma site, on the
southeastern coast of Lake Biwa, and reconstructed sediment
surface temperature history during the last 3000 years. The reconstructed temperature history shows apparent Medieval Warm
Period, Little Ice Age, and contemporary temperature warming.
However, the large amplitude of the temperature changes up to
4-5 K cannot be explained by past climatic change only, sug-
gesting that there was some other cause of the larger amplitude
temperature changes. The onsets of temperature decrease in
the late 12th century A. D. and temperature increase in the mid
17th century A. D. appear to coincide with occurrences of two
destructive earthquakes (1185 and 1662 A. D.) that caused water
level changes of Lake Biwa. It suggests that the reconstructed
sediment surface temperature history reflects the environmental
change due to tectonically induced water level changes of the
lake. If the annual mean of the ground surface temperature was
higher than that of the bottom water temperature in a shallow part
of the lake, which is consistent with the present-day data, the large
amplitude of the sediment surface temperature change may be
attributed to a combined effect of past climatic and environmental
changes. Thus, we suggest that the borehole temperature at the
Karasuma site preserves information not only on past climate
changes but also on environmental changes due to tectonically
induced water level changes. В© 2005 Elsevier B.V. All rights
reserved.
1512 Isotopic and biogeochemical markers help in reconstructing the Lazaret Cave environment (Nice, France) during upper Pleistocene (IOS-5) (French) (Apport des marqueurs
isotopiques et biogВґeochimiques dans la reconstitution du
palВґeoenvironnement de la grotte du Lazaret (Nice, Alpes-Maritimes) au cours du PlВґeistocène supВґerieur (stade isotopique 5))
Rousseau L., Beauchamp J., Falguères C. et al. Comptes Rendus
- Geoscience 2005 337/15 (1348-1354)
The isotopic composition of calcite from the stalagmitic floor
E of the Lazaret Cave is interpreted as proxy of atmospheric
circulation and vegetal cover changes during IOS 5. The 18O
variations could indicate change in precipitation sources, which
could originate from the Mediterranean Sea during warm periods
and from the Atlantic Ocean during colder periods. The 13C
variations could be related to vegetal cover and soil type. Tree
cover appears to be dominant according to pollen spectra, and
organic molecules trapped into calcite (sterols, terpenoids, humic
acids). В© 2005 AcadВґemie des sciences. PubliВґe par Elsevier SAS.
Tous droits rВґeservВґes.
1513 Aeolian process and pedogenesis under the influence of
the East Asian monsoon: A statistical approach to particlesize distribution variability
Parker E.J. and Bloemendal J. Sedimentary Geology 2005 181/34 (195-206)
The grain size of Chinese loess has been widely regarded as a
sensitive proxy for the intensity of the wind strength associated
with the winter component of the East Asian monsoon. The
majority of papers concerned with loess particle size examine
variations in moments of the particle size distribution. However, in coastal geomorphological research parametric models
have been used and the samples represented by resulting parameter estimates. Here we investigate the use of log-hyperbolic
and log-skew-laplace models to distinguish between loess, loess
subgroups and palaeosols in a particularly high accumulation
rate profile from the NW Chinese loess plateau area. The aim
is to define narrow units of вЂ�pristineвЂ™ loess that may indicate
brief returns to dust storm conditions. With this approach, units
within the loess, previously ascribed to Heinrich events, can
be seen to have a particular particle size distribution signature,
thus allowing them to be stratigraphically and environmentally
constrained. Parametric models applied to grain-size distribution
data in Chinese loess make a useful addition to previously used
particle size techniques that have demonstrated cyclicity on a
scale similar to that of Dansgaard-Oeschger events in ice cores
and those designed to determine the degree of loess pedogenesis
such as micromorphology and magnetic enhancement. The aim
of our work is to make full use of particle size distribution data
in the wider context of palaeoenvironmental reconstruction. В©
2005 Elsevier B.V. All rights reserved.
1514 An ostracode based paleolimnologic and paleohydrologic history of Death Valley: 200 to 0 ka
Forester R.M., Lowenstein T.K. and Spencer R.J. Bulletin of the
Geological Society of America 2005 117/11-12 (1379-1386)
Death Valley, a complex tectonic and hydrologic basin, was cored
from its lowest surface elevation to a depth of 186 m. The sediments range from bedded primary halite to black muds. Con-
THE QUATERNARY
tinental ostracodes found in the black muds indicate that those
sediments were deposited in a variety of hydrologic settings ranging from deep, relatively fresh water to shallow saline lakes to
spring discharge supported wetlands. The alkaline-enriched, calcium-depleted paleolake waters indicate extrabasinal streamflow
and basin-margin spring discharge. The alkaline-depleted, calcium-enriched paleowetland waters indicate intrabasinal spring
discharge. During Marine Isotope Stage 6 (MIS 6, ca. 180-140
ka) the hydrologic settings were highly variable, implying that
complex relations existed between climate and basin hydrology.
Termination II (MIS 6 to MIS 5E) was a complex multicyclic sequence of paleoenvironments, implying that climates oscillated
between high and low effective moisture. MIS 4 (ca. 73-61 ka)
was a spring discharge supported wetland complex. During MIS
2 (ca. 20-12 ka) the hydrologic settings were variable, although
they are not fully understood because some black muds deposited
during that time were lost during coring. В© 2005 Geological
Society of America.
1515 Temperature variations recovered from tree-rings in
the middle Qilian Mountain over the last millennium
Liu X., Qin D., Shao X. et al. Science in China, Series D: Earth
Sciences 2005 48/4 (521-529)
Based on the cross-dated tree-ring samples collected from the
middle Qilian Mountain, a standard ring-width chronology had
been developed, which covered the period AD 1000 to 2000. The
correlations between the chronology and climatic records from
the nearby meteorological stations indicated that temperature was
the dominant climatic factor for tree growth at upper timberline,
and the most important climatic factor for the tree growth in
the area was the mean temperature from previous December to
current April. The temperature variations recovered from the
ring-width data showed a cold period during the "Little Ice Age"
and the continuous warming during the twentieth century. Comparison between the ring-width chronology and 18 O records
from the Dunde ice core in the Qilian Mountain indicated that
there was a consistent trend in both time series. A significant
correlation existed between our ring-width chronology and the
Northern Hemispheric temperature, suggesting that the climate
changes in the Qilian Mountain were not only driven by regional
factors, but also responsive to the global climate. Copyright by
Science in China Press 2005.
1516 The Y. D. and climate abrupt events in the early and
middle Holocene: Stalagmite oxygen isotope record from
Maolan, Guizhou, China
Qin J., Yuan D., Cheng H. et al. Science in China, Series D:
Earth Sciences 2005 48/4 (530-537)
The isotope records which range from 3.9 kaBP to 15.7 kaBP with
an average resolution of 90 a have been obtained from 45 cm to
193.6 cm of the upper part of D4 stalagmite from Dongguo Cave
in Libo, Guizhou, by using system TIMS U-series dating and
carbon and oxygen stable isotope analyses. The study indicates
that the last cold event, the YD (Younger Dryas) event, of the last
glacial period was apparently shown in D4 record, which started
from 12.80 kaBP and ended in 11.58 kaBP, with a great range
of drop in temperature. The end of the last glacial period was
consistent with the termination I in oceanic isotope records and
was with time limit of 11.3 kaBP. The three most distinct cold
events in the early and middle Holocene occurred respectively
in 10.91 kaBP, 8.27 kaBP and 4.75 kaBP, with a range of drop
in temperature reaching 2 - 5В°C. The climate abrupt events in
thousand and hundred years scale recorded in stalagmite 18 O
can be compared to those in GISP2 ice cores from Greenland
in their happening time and the range of their lasting time. The
cold events in 8.27 kaBP and 4.75 kaBP can also be compared
to CC3 stalagmite records in Ireland, which indicate that climate
changes of short range in China monsoon areas, western Europe
and polar regions, have the same driving factor. This has a global
significance. In addition, the trend of record curves in some
time-stages is apparently different, which reflects probably the
difference between environment in monsoon climate areas and
in polar regions. Copyright by Science in China Press 2005.
287
1517 Sea-salt aerosol transport patterns over the Northern
Hemisphere inferred from two subarctic ice core records
Yan Y., Kang S., Sun J. et al. Science in China, Series D: Earth
Sciences 2005 48/4 (576-584)
Atmospheric circulation reconstruction based on glaciochemical
records requires knowledge of chemical concentration controls,
such as source, transport pathway and strength. To gain insight
into these processes, the relationships between glaciochemical
records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental
sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+ ) concentration and SLP
series show that ssNa + concentrations are closely correlated with
the autumntime (SON) Aleutian Low and the summertime (JJA)
North Pacific Subtropical High. Both the deepened Aleutian
Low and enhanced North Pacific Subtropical High strengthen the
transport of sea-salt aerosols from the North Pacific to the Mt.
Logan region. Calibrations between 20D ssNa+ concentrations
and SLP series indicate that ssNa+ concentrations are closely
related to the wintertime (Jan.) Icelandic Low. A deepening of
the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden
air masses to the Greenland ice sheet. Therefore, ice core ssNa +
records from the Mt. Logan region can be considered as a proxy
for reconstructing the autumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from
Greenland ice core (20D) may provide a proxy for reconstructing
the wintertime Icelandic Low. Copyright by Science in China
Press 2005.
1518 Lake sediment records on climate change and human
activities since the Holocene in Erhai catchment, Yunnan
Province, China
Shen J., Yang L., Yang X. et al. Science in China, Series D:
Earth Sciences 2005 48/3 (353-363)
According to high-resolution analyses on multi-proxy of sediment core from the Erhai Lake, Yunnan Province, the sequence
of climatic and environmental change since the Holocene has
been reconstructed based on accurate dating. The results show
that climate had transited from cold-wet to warm-wet during ca.
12950-8399 aBP in this area, and the transition happened in ca.
10329 aBP. Due to the enhancing southwest Asian monsoon and
increasing precipitation, the lake-level of the Erhai Lake began
to rise after ca. 10329 a BP. Climate in the catchment was
warm and wet during the mid-Holocene, and the warmest stage
appeared in ca. 8399-6371 a BP. The lake-level descended in
the mid-Holocene because of the decrease of effective moisture
in the basin. Human activities appeared in ca. 6371 a BP, and
the initial manner mainly focused on deforestation. Up to ca.
2139 a BP, due to the amount of immigration into this area, the
cultivation was developed widely, which was followed by mining
(coal mine). Copyright by Science in China Press 2005.
1519 Lithology and stratigraphy of sediment cores from the
Eifel dry maar lakes (German) (Lithologie und Stratigraphie
der spВЁatpleistozВЁanen Trockenmaare der Eifel)
Schaber K. and Sirocko F. Mainzer Geowissenschaftliche Mitteilungen 2005 -/33 (295-340)
Twentytwo long sediment cores from 12 Eifel dry maar lakes
and one modern lake are stratigraphically correlated to obtain
a continuous record of the history of sedimentation during the
last climatic cycle from today back to 140 000 years ago. The
backbone of the stratigraphy is based on 64 AMS 14 C dates, 4
luminescence dates and the occurrence of the 5 to 20 cm thick
deposits of the phonolithic DВЁumpelmaar tephra, which is found
in all records immediately above the annually laminated sections
of the last interglacial. Greyscale variations in the sections of
the last glacial show a stadial/ interstadial succession, which
is highly similar to the Greenland ice core NorthGRIP, which
allows high precision tuning of the stratigraphy, and document
also the tight link between the North Atlantic/Greenland climate
and central Europe. The sediments of the 22 cores reveal 3 different lithotypes, wh ich are synthesized into a general lithological
profile. Accordingly, the last interglacial sediments are always
fine grained laminae which allow varve counting in a few cases.
A short episode of strong seismic activity immediately after the
last interglacial caused seismites in the center of the lakes and
288
THE QUATERNARY
slumps around the flanks. Early Weichselian sediments are still
organic rich, but with much more clastic input than during the
interglacial. Massive slumps indicate a lake level regression during the beginning of the marine oxygen isotope stage 4, which
is then dominated by eolian sediments. The early interstadials
of MIS3 are again rich in organic carbon content, stadials reveal
abundant loess, which becomes dominating during the last glacial
maximum. The phonolithic tephra of the Laacher See eruption
is the second distinct chronological marker immediately above
a fast transition to high organic carbon contents at the begin of
the Holocene. This succession of sedimentation is typical for all
Eifel maar lakes and clearly reflects the climate evolution of the
last glacial cycle.
1520 Phosphorus geochemistry in the Luochuan loess section, North China and its paleoclimatic implications
Rao W., Chen J., Luo T. and Liu L. Quaternary International
2005 144/1 (72-83)
Total P (Pt ) on a carbonate-free basis in an entire loess-paleosol sequence and Pt , organic P (Po ) and inorganic P (Pi ) in the
S0 -L1 - S1 sequence were investigated in detail with different
resolutions for the Luochuan loess section from northern China.
Pt content varies between 393 and 786 ppm throughout the loesspaleosol sequence, and is generally higher in the loess than in
interstratified paleosols, showing fluctuation cycles of 100 ka in
correspondence to loess-paleosol alternations. Pt variations on
a carbonate-free basis in the loess-paleosol sequence could indicate variations in atmosphere precipitation resulting in different
leaching loss of P from paleosols. Pi has an average value of
499 ppm with a range of 324-560 ppm, accounting for more
than 70% of Pt in the S0 -L1 -S1 sequence, where the minimum
of Pi in the Malan loess is higher than the maximum of Pi in
S1 . Po ranges between 59 and 233 ppm with an average of 132
ppm in the S0 - L1 -S1 sequence. Phosphorus (P) was initially
delivered to the Luochuan loess section via influx of aeolian dust
from the northern desert and Gobi areas by the East Asian winter monsoon, and then was modified by pedogenesis associated
with the East Asian summer monsoon during the last 130 ka.
"Preserved Pt " in the loess L1 is tightly correlated with grain size
without leaching loss of P due to enrichment of P in fine-grained
fractions, as well as "initial Pt ". "Leaching Pt " data show that
paleosol S1 had lost 15-40% of its "initial Pt ", and that there
was much more precipitation in S1 than in L1 . Pi subject to
slightly weak pedogenesis was completely transformed into Po
without leaching loss of P in loess L1 . By contrast, much Pi
disappeared from paleosol S1 due to strong pedogenesis, partly
through leaching and partly through conversion to organic forms
during P cycling processes. Po variation is similar to those of MS
and the <7.8 m fraction in L1 , but contains more information on
the East Asian winter monsoon due to weak pedogenesis without
leaching of P. Po in S1 lower than L1 SS1 as a consequence of
strong decomposition of the organic matter kept constantly in the
middle of S1 where Pi kept at the lowest of 423 ppm, suggesting
that there existed a very warm and humid climate related to
the enhanced summer monsoon during that period. The mean
organic P/inorganic P ratio (Po /Pi ) is lower in the L1 LL1 and
L1 LL2 than in the S0 , S1 and L1 SS1 , indicating that low Po /Pi
ratios coincide with weak weathering-pedogenesis, and higher
Po /Pi ratios correspond to strong weathering-pedogenesis. Po /Pi
ratio can eliminate the effect of grain size on aeolian dust because
of chemical uniformity of aeolian dust and enrichment of Po and
Pi in the fine-grained fractions. Thus, Po / Pi ratio is solely linked
to pedogenesis of the Luochuan loess section. Variation in Po /Pi
ratio is similar to those of MS and the Marine Oxygen Isotope
composition, indicating the summer monsoon evolution during
the last 130 ka and providing the biogeochemical evidence for
further understanding the genetic links between the East Asian
monsoon and global climate change. В© 2005 Elsevier Ltd and
INQUA. All rights reserved.
1521 Modern pollen-rain characteristics of tall terra firme
moist evergreen forest, southern Amazonia
Gosling W.D., Mayle F.E., Tate N.J. and Killeen T.J. Quaternary
Research 2005 64/3 (284-297)
The paucity of modern pollen-rain data from Amazonia constitutes a significant barrier to understanding the Late Quaternary
vegetation history of this globally important tropical forest re-
gion. Here, we present the first modern pollen-rain data for
tall terra firme moist evergreen Amazon forest, collected between 1999 and 2001 from artificial pollen traps within a 500
20 m permanent study plot (14В°34 50 S, 60В°49 48 W) in
Noel Kempff Mercado National Park (NE Bolivia). SpearmanвЂ™s
rank correlations were performed to assess the extent of spatial
and inter-annual variability in the pollen rain, whilst statistically
distinctive taxa were identified using Principal Components Analysis (PCA). Comparisons with the floristic and basal area data
of the plot (stems 10 cm d.b.h.) enabled the degree to which
taxa are over/under-represented in the pollen rain to be assessed
(using R-rel values). Moraceae/Urticaceae dominates the pollen
rain (64% median abundance) and is also an important constituent
of the vegetation, accounting for 16% of stems 10 cm d.b.h.
and ca. 11% of the total basal area. Other important pollen taxa
are Arecaceae (cf. Euterpe), Melastomataceae/Combretaceae,
Cecropia, Didymopanax, Celtis, and Alchornea. However, 75%
of stems and 67% of the total basal area of the plot 10 cm
d.b.h. belong to species which are unidentified in the pollen
rain, the most important of which are Phenakospermum guianensis (a banana-like herb) and the key canopy-emergent trees,
Erisma uncinatum and Qualea paraensis. В© 2005 University of
Washington. All rights reserved.
1522 15,000-yr pollen record of vegetation change in the high
altitude tropical Andes at Laguna Verde Alta, Venezuela
Rull V., Abbott M.B., Polissar P.J. et al. Quaternary Research
2005 64/3 (308-317)
Pollen analysis of sediments from a high-altitude (4215 m), Neotropical (9В°N) Andean lake was conducted in order to reconstruct local and regional vegetation dynamics since deglaciation. Although deglaciation commenced 15,500 cal yr B.P., the
area around the Laguna Verde Alta (LVA) remained a periglacial
desert, practically unvegetated, until about 11,000 cal yr B.P. At
this time, a lycopod assemblage bearing no modern analog colonized the superpВґaramo. Although this community persisted until
6000 cal yr B.P., it began to decline somewhat earlier, in synchrony with cooling following the Holocene thermal maximum
of the Northern Hemisphere. At this time, the pioneer assemblage was replaced by a low-diversity superpВґaramo community
that became established 9000 cal yr B.P. This replacement coincides with regional declines in temperature and/or available
moisture. Modern, more diverse superpВґaramo assemblages were
not established until 4600 cal yr B.P., and were accompanied
by a dramatic decline in Alnus, probably the result of factors
associated with climate, humans, or both. Pollen influx from
upper Andean forests is remarkably higher than expected during the Late Glacial and early to middle Holocene, especially
between 14,000 and 12,600 cal yr B.P., when unparalleled high
values are recorded. We propose that intensification of upslope
orographic winds transported lower elevation forest pollen to
the superpВґaramo, causing the apparent increase in tree pollen at
high altitude. The association between increased forest pollen
and summer insolation at this time suggests a causal link; however, further work is needed to clarify this relationship. В© 2005
University of Washington. All rights reserved.
1523 Paleoecological and climatic changes of the Upper
Lerma Basin, Central Mexico during the Holocene
Ludlow- Wiechers B., Almeida- LeЛњnero L. and Islebe G. Quaternary Research 2005 64/3 (318-332)
The record of Almoloya Lake in the Upper Lerma basin starts
with the deposition of the late Pleistocene Upper Toluca Pumice
layer. The data from this interval indicate a period of climatic
instability that lasted until 8500 cal yr B.P., when temperature
conditions stabilized, although moisture fluctuations continued
until 8000 cal yr B.P. Between 8500 and 5000 cal yr B.P. a
temperate climate is indicated by dominance of Pinus. From
5000 to 3000 cal yr B.P. Quercus forest expanded, suggesting a
warm temperate climate: A first indication of drier environmental
conditions is an increase in grassland between 4200 and 3500 cal
yr B.P. During the Late Holocene (3300 to 500 cal yr B.P.) the
increase of Pinus and grassland indicates temperate dry conditions, with a considerable increase of Pinus between 1100 and
950 cal yr B.P. At the end of this period, humidity increased. The
main tendency during the Holocene was a change from humid
THE QUATERNARY
to dry conditions. During the Early Holocene, Almoloya Lake
was larger and deeper; the changing humidity regime resulted
in a fragmented marshland, with the presence of aquatic and
subaquatic vegetation types.
1524 A 23,000-yr pollen record from Lake Euramoo, Wet
Tropics of NE Queensland, Australia
Haberle S.G. Quaternary Research 2005 64/3 (343-356)
A new extended pollen and charcoal record is presented from
Lake Euramoo, Wet Tropics World Heritage rainforest of northeast Queensland, Australia. The 8.4-m sediment core taken
from the center of Lake Euramoo incorporates a complete record
of vegetation change and fire history spanning the period from
23,000 cal yr B.P. to present. The pollen record is divided into
five significant zones; 23,000-16,800 cal yr B.P., dry sclerophyll
woodland; 16,800-8600 cal yr B.P., wet sclerophyll woodland
with marginal rainforest in protected pockets; 8600-5000 cal yr
B.P., warm temperate rainforest; 5000-70 cal yr B.P., dry subtropical rainforest; 70 cal yr B.P.-AD 1999, degraded dry subtropical rainforest with increasing influence of invasive species
and fire. The process of rainforest development appears to be
at least partly controlled by orbital forcing (precession), though
more local environmental variables and human activity are also
significant factors. This new record provides the opportunity
to explore the relationship between fire, drought and rainforest
dynamics in a significant World Heritage rainforest region. В©
2005 University of Washington. All rights reserved.
1525 Paleoclimate changes during the last 100,000 yr from
a record in the Brazilian Atlantic rainforest region and interhemispheric comparison
Ledru M.- P., Rousseau D.- D., Cruz Jr. F.W. et al. Quaternary
Research 2005 64/3 (444-450)
A long terrestrial record, ColЛ†onia CO-3, from the Atlantic rainforest region in Brazil (23В°52 S, 46В°42 20 W, 900 m a.s.l.) registrates variations in the forest expansion during the last 100,000
yr. The 780-cm depth core was analyzed at 2-cm intervals and
arboreal pollen frequencies were compared to nearby speleothem
stable isotope records and neighboring marine records from the
tropical Atlantic. To evaluate regional versus global climate
forcing, our record was compared with Greenland and Antarctic
ice-core records. These comparisons suggest that changes in
temperature seen in polar latitudes relate to moisture changes:
e.g., to changes in the length of the dry season, in tropical and
subtropical latitudes during glacial as well as interglacial times.
These climatic changes result from changes in the frequency of
polar air incursions to these latitudes inducing a permanent cloud
cover and precipitation. This is an important result that should
help define paleoclimatic features in the Southern Hemisphere
for the last glaciation. В© 2005 University of Washington. All
rights reserved.
1526 A Holocene pollen and diatom record from Vanderlin
Island, Gulf of Carpentaria, lowland tropical Australia
Prebble M., Sim R., Finn J. and Fink D. Quaternary Research
2005 64/3 (357-371)
Sedimentary, palynological and diatom data from a dunefield
lake deposit in the interior of Vanderlin Island in the Gulf of
Carpentaria are presented. Prior to the formation of present
perennial lake conditions, the intensified Australian monsoon
associated with the early Holocene marine transgression allowed
Cyperaceae sedges to colonise the alluvial margins of an expansive salt flat surrounded by an open Eucalyptus woodland. As sea
level stabilised between 7500 and 4500 cal yr B.P. coastal dunes
ceased to develop allowing dense Melaleuca forest to establish
in a Restionaceae swamp. Dune-sand input into the swamp was
diminished further as the increasingly dense vegetation prevented
fluvial and aeolian transported sand arriving from coastal sources.
This same process impounded the drainage basin allowing a
perennial lake to form between 5500 and 4000 cal yr B.P. Myriophyllum and other aquatic taxa colonised the lake periphery
under the most extensive woodland recorded for the Holocene.
The palynological data support an effective precipitation model
proposed for northern Australia that suggests more variable conditions in the late Holocene. A more precise measure of effective
precipitation change is provided by diatom-based inferences that
indicate few changes in lake hydrology. Such interpretations are
289
explained in terms of palynological sensitivity to adjustments
in local fire regimes where regional precipitation change may
only be recorded indirectly through fire promoting mechanisms,
including intensified ENSO periodicity and human impact. В©
2005 University of Washington. All rights reserved.
1527 High-resolution pollen record from core KW31, Gulf
of Guinea, documents the history of the lowland forests of
West Equatorial Africa since 40,000 yr ago
Lezine A.- M. and Cazet J.- P. Quaternary Research 2005 64/3
(432-443)
Pollen data from core KW31 recovered off the mouth of the
Niger River (3В°31 1N-05В°34 1E; 1181 m water depth) provide
an exceptional record of vegetation changes in the West African lowlands between 40,000 and 3500 cal yr B.P. The highly
diverse microflora testify for the permanency of rain and secondary forests in the Niger river catchment, at least as gallery
formations along rivers, during the last glacial period when dry
conditions occurred in relation to enhanced trade-wind circulation. The direct consequence of the post-glacial warming and
the correlative increase in monsoon fluxes over West Africa was
the increase in forest diversity and the expansion of rain and
secondary forests on the nearby continent. Comparison between
KW31 pollen record and continental pollen data from 5В°S to
25В°N allows the evaluation of migration rates of tropical forest
populations throughout North West Africa at the beginning of the
Holocene and the vegetation response to the shift toward aridity
recorded widely at the end of the African Humid Period around
4000 cal yr B.P. В© 2005 University of Washington. All rights
reserved.
Oceans
1528 Analyses of a large-scale depositional clinoformal
wedge along the Italian Adriatic coast
Niedoroda A.Wm., Reed C.W., Das H. et al. Marine Geology
2005 222-223/1-4 (179-192)
The processes controlling the formation of the late Holocene
high-stand systems tract along the central Adriatic coast - a prograding clinoformal sediment wedge - have been diagnosed using
a large-scale behavior-oriented numerical model. This model is
based on time-averaged marine sediment dynamics, allowing it to
represent processes acting over millennial time spans. River-derived sediment is redistributed by the combined action of littoral,
shoreface and shelf processes. In this application the numerical
model successfully simulates both the overall geometry of the
deposits and the internal time-line stratigraphy. The simulation
of this prograding clinoform with the numerical model clearly
shows that the growth of these deposits depends on the combined effect of a strong and persistent coast-parallel advection
and cross-shelf dispersion related to a large number of sediment
re-entrainment events. This means that this clinoform is in the
process of forming a new shelf surface with an offshore profile
that is in adjustment with the present wave and current climate
along with the relative stability of sea level over the past six
millennia. В© 2005 Elsevier B.V. All rights reserved.
1529 Delta progradation and sediment fluxes since the last
glacial in the Thermaikos Gulf and the Sporades Basin, NW
Aegean Sea, Greece
Lykousis V., Karageorgis A.P. and Chronis G.Th. Marine Geology 2005 222-223/1-4 (381-397)
Late Quaternary sedimentary cover in the Thermaikos Gulf consists of three seismic Units: (i) the uppermost Unit A that
represents delta progradation during the last 6000 yr when the
sea surface almost reached the present level (Highstand Systems Tract, HST); (ii) Unit B that includes relatively coarsegrained sediments deposited in a shallow, high-energy, estuarine
environment during the post-glacial transgression (Transgressive
Systems Tract, TST); and (iii) the lowest Unit C which may
represent late glacial prodeltaic deposits and slope to basin turbidites (Lowstand Systems Tract, LST). Seismic units A and B
overlay a well-defined unconformity which resulted from subaerial erosion during the late glacial sea-level fall. Subtracting
290
THE QUATERNARY
the thickness of Unit A from the present bathymetry, the paleorelief of the Late Holocene times (ca. 6000 yr BP, sea level up to
- 20 m) was assessed. Similarly, the paleo-relief 24 000 yr BP
(sea level - 100 to - 120 m) was estimated. The main morphological feature is the incised valley of a major river that resulted
from the confluence of the Axios, Aliakmon, Loudias, Gallikos
and possibly Pinios Rivers. Sediment fluxes in the NW Aegean
Sea were estimated for three time spans of the Late Quaternary
(Interval I: 6000 yr BP-present, Interval II: 18 000- 6000 yr BP
and Interval III: 24 000-18 000 yr BP). The terrestrial sediment
load supplied by the Axios, Aliakmon, Pinios, and smaller rivers,
was estimated at 35.4 109 t for Interval I. 93% of this material
was deposited on the continental shelf, whereas the remaining
7% was transported to the adjacent basin. The mean annual
terrestrial flux was estimated at 5.5 106 t yr-1 . During Interval
II, more than 79 109 t of terrestrial sediment were discharged
into the area (terrestrial flux 6.6 106 t yr-1 ), of which 86% was
deposited on the shelf. During Interval III, the terrestrial load
was 40.6 109 t (terrestrial flux 6.8 106 t yr -1 ), and sediments
were predominantly deposited on the slope and basin. Based on
the sedimentвЂ™s carbonate content, the biogenic loads and fluxes
were also determined. The biogenic flux during Intervals II and
III was found to be 2.5-times higher than during Interval I. В©
2005 Elsevier B.V. All rights reserved.
1530 Isotopic and elemental records in a non-tropical coral
(Cladocora caespitosa): Discovery of a new high-resolution
climate archive for the Mediterranean Sea
Silenzi S., Bard E., Montagna P. and Antonioli F. Global and
Planetary Change 2005 49/1-2 (94-120)
A 95-year annual record of skeletal Sr / Ca, Mg / Ca, 18 O and
13 C is reported for a non-tropical, slow-growing coral (Cladocora caespitosa) collected in the north-western Mediterranean
Sea. Significant correlations were found for Sr / Ca vs. Mg
/ Ca, Sr / Ca vs. 18 O and for 18 O vs. 13 C, indicating the
possibility of using this non-tropical species as a climatic and
paleoclimatic biomarker. The Sr / Ca and Mg / Ca ratios as
well as the 18 O composition in corals were compared against
the Sea Surface Temperature (SST) data of IGOSS (Integrated
Global Ocean Service System Products) for the north-western
Mediterranean region. The Sr / Ca ratios show a significant
correlation with the SST, according to the following equation: Sr
/ Ca (mmol/mol) = 11.25 ( 0.38) - 0.079 ( 0.026) SST (В°C).
The 18 O data do not appear to fit with the SST interval used,
since the regression obtained is non-significant. This implies that
other factors apart from temperature, such as the 18 O seawater , are
affecting the coral 18 O. The relationship between Mg / Ca ratio
and SST is not statistically significant. This is probably due to
the heterogeneities in magnesium content found among the coral
microstructures (calcification centres, surrounding fibres and dissepiments), along with other factors, such as the presence of
microborings and/or organic matter. The annual record indicates
a history of SST variation that is consistent with the instrumental
measurements, and strongly suggests the feasibility of using this
non-tropical coral as a new proxy for the Mediterranean Sea. В©
2005 Elsevier B.V. All rights reserved.
1531 Late Quaternary sea-level highstands in the central
and eastern Indian Ocean: A review
Woodroffe C.D. Global and Planetary Change 2005 49/1-2 (121138)
The relative sea-level history of several atolls in the central
and eastern Indian Ocean, including the Cocos (Keeling) Islands, Chagos Archipelago, and the Maldives-Laccadive Archipelagoes, has been debated for over a century but takes on a
particular significance in the face of anticipated climate change.
For each of these central and eastern Indian Ocean atolls Pleistocene limestone is encountered at depths of 6-20 m below sea
level. On the Cocos (Keeling) Islands this has been dated to
Last Interglacial age. Conglomerate platform underlies the reef
islands on Cocos within which a sequence of fossil microatolls of
massive and branching Porites records a gradual fall of sea level
relative to the atoll. In the Maldives, the significance of outcrops
of вЂ�reef rockвЂ™ has been vigorously debated without resolving
sea-level history. Although in situ Heliopora occurs on the reef
flat of Addu Atoll, dated at around 2700 radiocarbon yrs BP,
other evidence for higher sea level remains poorly constrained.
Conglomerates of a similar age have been described from the
Chagos Archipelago, but it has not been unequivocally demonstrated that they formed under conditions of relatively higher sea
level. In contrast to reefs further west in the Indian Ocean, each
of these atolls has living microatolls of massive Porites that have
been constrained in their upward growth by sea level. Interpretation of the upper surface of two such specimens from the
Cocos (Keeling) Islands indicates broad fluctuations in the sea
surface over the past century; similar microatolls are described
from the Maldives implying little change in sea level over recent
years. Regardless of minor past fluctuations, most reef islands
in the Maldives are particularly low-lying and appear vulnerable
to inundation, and extracting a more detailed sea-level history
remains an important challenge. В© 2005 Elsevier B.V. All rights
reserved.
1532 Palaeoceanography of the Banda Sea, and Late Pleistocene initiation of the Northwest Monsoon
Spooner M.I., Barrows T.T., De Deckker P. and Paterne M.
Global and Planetary Change 2005 49/1-2 (28-46)
This paper details the Late Quaternary palaeoceanography of the
Banda Sea based on analysis of core SHI 9016, located east of
Timor. This core is located below the pathway of the Indonesian
Throughflow, at a depth of 1805 m bsl. Planktonic foraminifera
assemblages, the 18 O and 13 C of the foraminifer Globigerinoides ruber, and the total carbonate content of each sample were
used to reconstruct the vertical structure of the water column
through the past 80,000 yr. Today, the core site is characterised by high sea-surface temperature and high precipitation,
which results in the formation of a low-salinity boundary layer.
Sea-surface temperature estimates down core indicate minimal
cooling during the last glacial maximum. Mean sea-surface
temperatures ranged between 29.8В°C and 26.6В°C for the past
80,000 yr; sea-surface seasonality never increased above 3В°C. In
addition, the abundance of the planktonic foraminifera Neogloboquadrina dutertrei, Neogloboquadrina pachyderma, and Globigerinoides quadrilobatus indicates that the mixed layer (the
low-salinity boundary layer of the Throughflow) thinned during
Marine Isotope Stages 3 and 2. This enhanced a deep chlorophyll
maximum (DCM) layer. The Northwest Monsoon was less intense for about 60,000 yr and then вЂ�switched onвЂ™ at 15,000 cal
yr BP. This thickened the mixed layer, reducing the DCM, and
increased SST seasonality in the Banda Sea. В© 2005 Elsevier
B.V. All rights reserved.
1533 Inherent correlation between decreased marine sedimentary phosphorus and glacial atmospheric CO2 decline
Weng H.- X., Qin Y.- C. and Weng J.- K. Geophysical Research
Letters 2005 32/18 (1-4)
The environmental and biogeochemical information implicated
by a sediment column from the northern shelf of the South China
Sea suggests that the vertical phosphorus variation in the sediment column bares a negative correlation with those of calcium
carbonate and cadmium. The functional correlation between CO2
and PO34 in seawater is given by calculating a series of chemical equilibriums, indicating a coupling relationship between the
accumulation of marine sedimentary P and the atmospheric CO2
change. The decreased P accumulation in marine sediments
correlated to the increase of marine primary production during the glacial period might act as a key factor causing glacial
atmospheric CO2 decline. Copyright 2005 by the American
Geophysical Union.
1534 Changes in the source and transport mechanism of terrigenous input to the Indian sector of Southern Ocean during
the late Quaternary and its palaeoceanographic implications
Thamban M., Naik S.S., Mohan R. et al. Proceedings of the
Indian Academy of Sciences, Earth and Planetary Sciences 2005
114/5 (443-452)
Changes in the terrigenous sediment source and transport mechanisms during the late Quaternary have been investigated using
four sediment cores within the Indian sector of Southern Ocean,
using the magnetic susceptibility (MS) and sedimentological
records. Sediments deposited during the Holocene and other
interglacial periods were characterised by low MS, low sand
content, reduced ice-rafted detritus (IRD) input and increased
THE QUATERNARY
illite possibly transported via hydrographic advection from the
south. The glacial intervals are characterised by high MS, high
sand content, increased IRD input and reduced illite clays, derived from both local as well as Antarctic sources. Significant
reduction in clay fraction and illite content during glacials suggests that the erosive and transporting capabilities of the deep
and bottom waters could have reduced compared to the interglacial times. The changes in terrigenous influx to this region
were significantly influenced by the rhythmic glacial-interglacial
fluctuations in bottom circulation and the position of the Polar
Front. В© Printed in India.
1535 Palaeoceanographic implications of abundance and
mean proloculus diameter of benthic foraminiferal species
Epistominella exigua in sub-surface sediments from distal
Bay of Bengal fan
Saraswat R., Nigam R. and Barreto L. Proceedings of the Indian
Academy of Sciences, Earth and Planetary Sciences 2005 114/5
(453-458)
Temporal variation in abundance and mean proloculus diameter
of the benthic foraminiferal species Epistominella exigua has
been reconstructed over the last 50,000 yr BP, from a core
collected from the distal Bay of Bengal fan, to assess its potential
application in palaeoceanographic reconstruction studies. The
down-core variation shows significant change in abundance of E.
exigua during the last 50,000 yr BP. In view of the present day
abundance of this species from areas with strong seasonal organic
matter supply, we conclude that at 7, 22, 33 and 46
kyr BP, strong seasonality prevailed in the distal Bay of Bengal
fan, probably indicating either strong or prolonged north-east
monsoon or weakened south-west monsoon. For the first time, a
strong correlation is observed in abundance and mean proloculus
diameter of E. exigua. Based on coherent variation in mean
proloculus diameter and abundance, it is postulated that mean
proloculus diameter can also be used to infer increased seasonality in organic matter production, thus variation in strength or
duration of monsoon. Thus, this study establishes that the downcore vaxiation in the abundance and mean proloculus diameter of
Epistominella exigua can be used to infer past climatic variations
from the distal Bay of Bengal fan. В© Printed in India.
1536 Stable isotopes and sclerochronology of the bivalve
Mesodesma donacium: Potential application to Peruvian paleoceanographic reconstructions
CarrВґe M., Bentaleb I., Blamart D. et al. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/1-2 (4-25)
Reconstructing the past ENSO (El NiЛњno Southern Oscillation)
interannual variability requires very high resolution sea surface
temperature (SST) proxies. In order to compensate for the lack
of coral archive in the Eastern Pacific cold tongue, we studied the potentiality of the bivalve species Mesodesma donacium
as a SST tracer for the Peruvian coast. Biomineralisation cycles and growth line formation in the shells are shown to be
controlled by tides. The sclerochronology based on fortnightly
cycles allowed us to compare local SST data with high resolution shell records. As a result of the high correlation between
SST and aragonite 18 O, we calculated a linear SST-fractionation relationship for the 14-20В°C range: T(В°C)=(17.41 1.15)(3.66 0.16) ( 18 Oarag./PDB - 18
Owat./SMOW ). The difference from
the commonly used Grossman and Ku (1986) [Grossman, E.L.,
Ku, T.L., 1986. Oxygen and carbon fractionation in biogenic
aragonite: temperature effect. Chemical Geology 59, 59-74]
equation suggests the potential existence of a species dependence of vital effect within bivalves. This preliminary equation
allows monthly-scale SST reconstructions with a 1.5В°C precision using M. donacium archaeological shells from southern
Peru, giving potential insights into the problem of past ENSO
behaviour. В© 2005 Elsevier B.V. All rights reserved.
1537 Orbitally paced paleoproductivity variations in the Timor Sea and Indonesian throughflow variability during the
last 460 kyr
Holbourn A., Kuhnt W., Kawamura H. et al. Paleoceanography
2005 20/3 (1-18)
A high-resolution ( 1-2 kyr) multiproxy record from the Timor Sea in the easternmost Indian Ocean (International Marine
Global Change (IMAGES) Program Core MD01-2378, latitude
291
13В°04.95 S, longitude 121В°47.27 E, 1783 in water depth) closely
tracks changes in intermediate water ventilation and paleoproductivity over the last 460 kyr within one of the main outflow
passages of the Indonesian Throughflow. Spectral analysis of
five different flux-based productivity proxies indicates spectral
power concentrated in the 100 kyr (glacial-interglacial) and the 23
kyr and 19 kyr (precessional) periods. Paleoproductivity maxima
lead ice volume (benthic 18 O) maxima by 20В° to 40В° ( 1300
to 2600 years) at the precession band. The spectral differences
in tropical paleoproductivity records from the Pacific and Indian
oceans suggest that local processes (wind and circulation patterns
driven by insolation) are dominant in driving productivity rather
than large-scale tropical features. In the Timor Sea, productivity
fluctuations over the last 460 kyr were strongly influenced by
monsoonal wind patterns offshore NW Australia (23 and 19 kyr)
and were also modulated by sea level-related variations in the
intensity of the Indonesian Throughflow (100 kyr). Copyright
2005 by the American Geophysical Union.
1538 Diatom-bound 15 N/14 N: New support for enhanced nutrient consumption in the ice age subantarctic
Robinson R.S., Sigman D.M., DiFiore P.J. et al. Paleoceanography 2005 20/3 (1-14)
Diatom-bound 15 N/14 N was used to reconstruct the glacial nutrient status of the Subantarctic Zone in the Southern Ocean.
Down-core records from both the Pacific and Indian sectors
show 15 N of 5 to 6%вЂ° during the Last Glacial Maximum
and a decrease, coincident with the glacial termination, to values
as low as 2вЂ°. The effect of either diatom assemblage or physiological change on the diatom-bound 15 N/14 N is unknown and
cannot yet be ruled out as a possible explanation for the observed
change. However, the consistency between Indian and Pacific
sector records and with other paleoceanographic data suggests
that the glacial-interglacial difference in diatom-bound 15 N/14 N
was driven by higher consumption of nitrate in the subantarctic surface during the last ice age. Such a change in nutrient
consumption may have resulted from atmospheric iron fertilization and/or decreased glacial mixed layer depths associated with
sea ice melting. Enhanced nutrient consumption in the glacial
subantarctic would have worked to lower the concentration Of
CO2 in the ice age atmosphere. It also would have reduced
the preformed nutrient content of the low-latitude thermocline,
leading to decreases in lowlatitude productivity, suboxia, and
denitrification. Copyright 2005 by the American Geophysical
Union.
1539 Glacial to interglacial changes in the settling depth of
the Mediterranean Outflow plume
Rogerson M., Rohling E.J., Weaver P.P.E. and Murray J.W. Paleoceanography 2005 20/3 (1-12)
We present micropalaeontological and grain-size records for a set
of sediment cores from the Gulf of Cadiz (southwest Spain) that
reflect changes in the position and strength of the Mediterranean
Outflow (MO) current. The cores sample a sediment drift (the
Gil Eanes Drift) that is positioned lower on the slope in the Gulf
of Cadiz than the position of the main current today. The data
indicate that the drift is of glacial age and that the glacial MO
current was positioned lower on the slope than today but also that
it was active over a considerably reduced area of the slope. We
argue that this observation is consistent with physical constraints
on the Gibraltar Exchange and on the likely settling and spreading
behavior of the MO plume along the Iberian Margin under glacial
environmental and sea level conditions. The deeper settling of
the MO is likely to have influenced the formation of glacial North
Atlantic Intermediate Water and also may have exerted indirect
influence on the formation of glacial North Atlantic Deep Water.
Copyright 2005 by the American Geophysical Union.
1540 Ocean climate variability in the eastern North Atlantic
during interglacial marine isotope stage 11: A partial analogue to the Holocene?
de Abreu L., Abrantes F.F., Shackleton N.J. et al. Paleoceanography 2005 20/3 (1-15)
Similar orbital geometry and greenhouse gas concentrations during marine isotope stage 11 (MIS 11) and the Holocene make
stage 11 perhaps the best geological analogue period for the
natural development of the present interglacial climate. Results
292
THE QUATERNARY
of a detailed study of core MD01-2443 from the Iberian margin
suggest that sea surface conditions during stage 11 were not
significantly different from those observed during the elapsed
portion of the Holocene. Peak interglacial conditions during
stage 11 lasted nearly 18 kyr, indicating a Holocene unperturbed
by human activity might last an additional 6-7 kyr. A comparison of sea surface temperatures (SST) derived from planktonic
foraminifera for all interglacial intervals of the last million years
reveals that warm temperatures during peak interglacials MIS 1,
5e, and 11 were higher on the Iberian margin than during substage
7e and most of 9e. The SST results are supported by heavier 18 O
values, particularly during 7e, indicating colder SSTs and a larger
residual ice volume. Benthic 13 C results provide evidence of a
strong influence of North Atlantic Deep Water at greater depths
than present during MIS 11. The progressive ocean climate
deterioration into the following glaciation is associated with an
increase in local upwelling intensity, interspersed by periodic
cold episodes due to ice-rafting events occurring in the North
Atlantic. Copyright 2005 by the American Geophysical Union.
1541 Problems with paleoproductivity proxies
Anderson R.F. and Winckler G. Paleoceanography 2005 20/3
(1-7)
Difficulties associated with reconstructing past changes in export production were highlighted recently by Averyt and Paytan
(2004), who reported substantial disagreement among records
developed using different paleoproductivity proxies extracted
from two equatorial Pacific piston cores. Proxies included the
accumulation rates of barite, excess Ba, and excess as well as
elemental ratios of A1/Ti and Ba/Ti. Here we build upon their
work by presenting evidence for two factors that contributed to
these discrepancies. First, elemental (Ba/Ti and Al/ Ti) ratios
are influenced by variability in space and time of the flux of
Ti to equatorial Pacific sediments, so these proxies cannot be
expected to hold a constant relationship to export production.
Second, the late Holocene increase in CaCO3 dissolution has
caused concentrations of barite, excess Ba, and excess Al to be
enriched in surface sediments relative to the depth interval over
which sediment accumulation rates were evaluated in developing
the algorithms used by Averyt and Paytan (2004). This produces
an error in the accumulation rates of these proxies that varies
from core to core, ranging from a few tens of percent to as much
as a factor of 3. These errors would have been propagated into
the export production algorithms on the basis of fluxes of barite,
excess Ba, and excess Al. Furthermore, this bias created by
the late Holocene increase in CaCO3 dissolution will affect the
development of any algorithm based on fluxes of sedimentary
constituents. These factors must be taken into account in future paleoceanographic reconstructions. Copyright 2005 by the
American Geophysical Union.
1542 Temporal and spatial variation in tetraether membrane lipids of marine Crenarchaeota in particulate organic
matter: Implications for TEX86 paleothermometry
Wuchter C., Schouten S., Wakeham S.G. and Sinninghe
DamstВґe J.S. Paleoceanography 2005 20/3 (1-11)
The TEX86 is a new temperature proxy which is based on the
number of cyclopentane moieties in the glycerol dialkyl glycerol
tetraether (GDGT) lipids of the membranes of Crenarchaeota that
occur ubiquitously in oceans and shelf seas. This proxy was calibrated by core top sediments, but it is as yet not clear during which
season and at which depth in the water column the GDGT signal
used for TEX86 paleothermometry is biosynthesized. Here we
analyzed >200 particulate organic matter (POM) samples from
11 different marine settings for TEX86 . This revealed that the
GDGTs occur seasonally in surface waters and occur in higher
abundances during the winter and spring months. The depth
distribution showed that GDGTs generally appeared in higher
amounts below 100 m depth in the water column. However, the
TEX86 values for waters below the photic zone (150-1500 m) did
not correlate with the in situ temperature but rather correlated
linearly with surface temperature. The TEX86 for POM from the
upper 100 m showed a linear correlation with in situ temperature,
which was nearly identical to the previously reported core top
equation. The correlation of all POM samples with surface temperature was also strikingly similar to the core top correlation.
These findings demonstrate that the GDGT signal which reaches
the sediment is mainly derived from the upper 100 m of the
water column. This may be caused by the fact that GDGTs
from the photic zone are much more effectively transported to
the sediment by grazing and repackaging in large particles than
GDGTs from deeper waters. Copyright 2005 by the American
Geophysical Union.
1543 Reconstruction of paleo-particulate organic carbon
fluxes for the Campbell Plateau region of southern New
Zealand using the zinc content of sponge spicules
Ellwood M.J., Kelly M., Neil H. and Nodder S.D. Paleoceanography 2005 20/3 (1-15)
The zinc concentration of siliceous sponge spicules was determined from spicules recovered from four sediment cores spanning the last 160 kyr, from the Campbell Plateau region southeast
of New Zealand. Zinc/Si results showed little difference between
Holocene and glacial aged spicules. An increase in Zn/Si was observed for core Y14, where Zn/Si peaked at about 0.6 mol/mol
during marine isotope stages 5a-5b. To better understand the
role carbon export has on sponge Zn/Si, we explored the strong
relationship observed between surficial sediment particulate organic carbon (POC) and the Zn/Si of sponge silica and related
this to sediment trap POC flux estimates. Conversion of the Zn/
Si records to benthic POC fluxes suggests that there has been
little change in the amount of POC reaching Campbell Plateau
sediments over the past 30 kyr. These results suggest that surface
productivity over the Campbell Plateau has remained relatively
low over the past 160 kyr and suggests that glacial productivity
was not significantly higher than the present day. Finally, this
work reveals that living marine sponges appear to act as the
biological equivalents of moored sediment traps, recording the
flux of POC to the seafloor by archiving zinc associated with
sinking POC in the growing silica skeleton. Copyright 2005 by
the American Geophysical Union.
1544 Methane-driven late Pleistocene 13 C minima and
overflow reversals in the southwestern Greenland Sea
Millo C., Sarnthein M., Erlenkeuser H. and Frederichs T. Geology
2005 33/11 (873-876)
A core transect across the southwestern Greenland Sea reveals
coeval events of extremely negative planktic and benthic 13 C
excursions between 40 and 87 ka. The most pronounced event,
event 1, began at peak Dansgaard-Oeschger stadial 22 (85 ka)
with a duration of 18 k.y. During this episode, incursions of Atlantic Intermediate Water caused a bottom-water warming of up
to 8В°C. The amplitude, timing, and geographic pattern of the 13 C
events suggest that this bottom-water warming triggered clathrate
instability along the East Greenland slope and a methane-induced
depletion of 13 CDIC (DIC - dissolved inorganic carbon). Since
13 C event 1 matches a major peak in atmospheric CH concen4
tration, this clathrate destabilization may have contributed to the
rise in atmospheric CH4 and thus to climate warming over marine
isotope stage 5.1. В© 2005 Geological Society of America.
1545 Late Quaternary paleoenvironmental changes in the
southeastern Yellow Sea, Korea
Kong G.S., Park S.- C., Han H.C. et al. Quaternary International
2005 144/1 (38-52)
A 34-meter-long AMS 14 C-dated sediment core was examined
in order to reconstruct the paleoenvironmental changes that have
taken place in the southeastern Yellow Sea during the last 16,600
years. To achieve this, we analyzed the geochemical compositions of organic matter, the benthic foraminiferal assemblages,
and the stable isotopes of benthic foraminiferal tests. The organic geochemical results show that terrigenous organic matter
was dominant in the southeastern Yellow Sea between 16,600
and 4300 cal. yr BP, probably due to the influence of river
runoff; marine organic matters, originating from surface primary
productivity, began increasing drastically after 4300 cal. yr BP.
Benthic foraminiferal assemblages reveal that brackish species
were dominant before 3500 cal. yr BP, but the saline species dominated after this time. The 18 O values of the benthic foraminifer
Cibicides lobatulus showed that a change from high-amplitude to
low-amplitude fluctuations took place at 3500 cal. yr BP. These
multi-results indicate that the southeastern Yellow Sea changed
from an estuarine to a modern marine shelf environment, proba-
THE QUATERNARY
bly due to the inflow of the Yellow Sea Warm Current, between
4300 and 3500 cal. yr BP. The time discrepancy of 800 years
indicates that a modern marine shelf environment was not fully
developed in the southeastern Yellow Sea until 3500 cal. yr BP,
even though the sea began to be influenced by the oceanic current
at 4300 cal. yr BP. В© 2005 Elsevier Ltd and INQUA. All rights
reserved.
Tropics and sub-tropics
1546 Modern pollen spectra from the highlands of the Cordillera Central, Dominican Republic
Kennedy L.M., Horn S.P. and Orvis K.H. Review of Palaeobotany
and Palynology 2005 137/1-2 (51-68)
We studied pollen, spores, and pine stomata in surface pond and
bog sediments and surface soils to characterize modern pollen
deposition in highland plant communities of the Cordillera Central, Dominican Republic. We collected our samples at 47 sites
representing a range of elevations (1200-3000 m) and cover types
on both the windward and leeward flanks of the cordillera. Pollen
from the endemic West Indian pine dominated surface spectra in
nearly all forested sites, as well as in most grasslands. Detrended
correspondence analysis (DCA) revealed that the modern pollen
spectra of forested uplands and open wetland sites are clearly
distinct, while other site types that are intermediate in terms
of vegetation are also intermediate in terms of modern pollen
spectra. The DCA also separated windward from leeward sites
based mainly on higher pollen percentages of broadleaf trees and
shrubs in the windward sites. A lack of pine stomata was an
excellent indicator of treelessness in grassland sites. This clear
distinction between treeless and forested sites may be useful in
interpreting highland fossil records that date to the last glacial
period. В© 2005 Elsevier B.V. All rights reserved.
1547 Stratigraphical and palynological appraisal of the Late
Quaternary mangrove deposits of the west coast of India
Kumaran K.P.N., Nair K.M., Shindikar M. et al. Quaternary
Research 2005 64/3 (418-431)
The organic deposits derived from the mangrove swamps form
reliable stratigraphic markers within the Late Quaternary sequence of Kerala - Konkan Basin. Three generations of such
deposits have been identified. The older one is dated to around
43,000-40,000 14 C yr B.P., with a few dates beyond the range
of radiocarbon. The younger ones date from the Middle Holocene to latest Pleistocene (10,760-4540 14 C yr B.P.) and the Late
Holocene (<4000 14 C yr B.P.). Pollen analyses confirm that
the deposits are mostly derived from the mangrove vegetation.
Peat accumulation during the period 40,000-28,000 14 C yr B.P.
can be correlated with the excess rainfall, 40-100% greater than
modern values, of the Asian summer monsoon. The low occurrence of mangrove between 22,000 and 18,000 14 C yr B.P.
can be attributed to the prevailing aridity and/or reduced precipitation associated worldwide with Last Glacial Maximum,
because exposure surfaces and ferruginous layers are commonly
found in intervals representing this period. The high rainfall of
11,000-4000 14 C yr B.P. is found to be the most significant as
the mangrove reached an optimum growth around 11,000 14 C
yr B.P. but with periods of punctuated weaker monsoons. From
the present and previous studies, it has been observed that after
about 5000 or 4000 14 C yr B.P., the monsoons became gradually
reduced leading to drying up of many of the marginal marine
mangrove ecosystems. A case study of Hadi profile provided an
insight to the relevance of magnetic susceptibility (x) to record
the ecological shift in Late Holocene. В© 2005 University of
Washington. All rights reserved.
1548 How a wet tropical rainforest copes with repeated volcanic destruction
Jago L.C.F. and Boyd W.E. Quaternary Research 2005 64/3
(399-406)
The Holocene Period for the province of West New Britain, Papua
New Guinea, is characterised by periodic catastrophic volcanism.
The region is mantled in dense wet tropical rainforest, and has
been occupied by people since the Pleistocene. Analyses of peat
from two nearby sites within a lowland rainforest environment
293
provide us with a macro-level landscape account of the periodic
destruction and recovery of the coastal forests during seven periods of volcanic activity in the latter part ( 2900 yr ago to present)
of the Holocene. Radiocarbon dating shows the very close correlation of the peat and tephra layers at both sites, yet the pollen
analysis reveals different vegetation communities. These initial
results allow us to begin identifying the processes of recovery, and
to recognise different ecological pressures placed on vegetation
at these neighbouring sites. Evidence of hydrological changes
are observed beginning with a marine incursion recorded at Garu
Site 3 1360 14 C yr B.P. The distinct differences in the vegetation re-establishment and community regeneration rates suggest
the greater level of disturbance at Garu Site 1 could be related
to the depth of the ashfall, although the proximity of a known
human settlement may also be a contributing factor. Of note,
palynologically, we found that the fern spore flora is particularly
rich and believe it will be useful for ecological interpretation. В©
2005 University of Washington. All rights reserved.
Mid-latitude and extra-glacial
1549 Estimating relevant source area of pollen for small
Danish lakes around AD 1800
Nielsen A.B. and Sugita S. Holocene 2005 15/7 (1006-1020)
The aims of this study were to obtain estimates of the relevant
source area of pollen (RSAP) that can be used to interpret fossil
pollen diagrams from medium sized lakes, and to elucidate factors affecting RSAP for such lakes. A data set of sediment pollen
assemblages dating from AD 1800 from 25 Danish lakes (3-27
ha) and land cover around the same lakes from historical maps
was used. The plant abundance data were distance weighted
using a species-specific model of pollen dispersal/deposition and
other distance weighting functions (1, 1/d and 1/d2 ). Extended
R-value models were applied to evaluate the relationship between
pollen and plant abundance and to estimate RSAP. The choice
of distance weighting function influenced the RSAP estimates.
When using the species-specific model, wind speed and speciesspecific properties of pollen dispersal had little effect on the
RSAP estimates, which were approximately 1700 m in radius,
when all lakes were analysed together. When the pollen types
were classified into fewer groups, the RSAP estimate increased,
probably because this procedure affected the spatial pattern of
the plant abundance data by, in effect, increasing patch size.
When the lakes were classified into two distinct groups (western Jutland and remaining sites) using a multivariate statistical
technique (TWINSPAN), we obtained different RSAP estimates
for each of the two groups. This result could be explained by a
difference in average patch size of the land cover types between
regions. A series of simulations supported our interpretation that
the patch size was the main factor determining the size of the
RSAP for the Danish lakes at AD 1800. В© 2005 Edward Arnold
(Publishers) Ltd.
1550 Aeolian sand preserved in Silver Lake: A new signal
of Holocene high stands of Lake Michigan
Fisher T.G. and Loope W.L. Holocene 2005 15/7 (1072-1078)
Aeolian sand within lake sediment from Silver Lake, Michigan
can be used as a proxy for the timing of high lake levels of Lake
Michigan. We demonstrate that the sand record from Silver Lake
plotted as percent weight is in-phase with the elevation curve of
Lake Michigan since the mid-Holocene Nipissing Phase. Because fluctuations in Lake MichiganвЂ™s lake level are recorded
in beach ridges, and are a response to climate change, the aeolian sand record within Silver Lake is also a proxy for climate
change. It appears that increases in dune activity and lake sand
are controlled by similar climatic shifts that drive fluctuations in
lake level of Lake Michigan. High lake levels destabilize coastal
bluffs that drive dune sand instability, and along with greater
wintertime storminess, increase niveo-aeolian transport of sand
across lake ice. The sand is introduced into the lake each spring
as the ice cover melts. В© 2005 Edward Arnold (Publishers) Ltd.
294
THE QUATERNARY
1551 Holocene paleosols of the Upo wetland, Korea: Their
implications for wetland formation
Nahm W.- H., Kim J.- K., Yang D.- Y. et al. Quaternary International 2005 144/1 (53-60)
A 4.490 m long core UP-1 was recovered from the marginal part
of the Upo wetland. The wetland is a typical riverine wetland
in Korea and has been designated as a Protected Wetland in
accordance with the International Ramsar Treaty. We studied
the Holocene environmental changes of the Upo wetland and the
depositional conditions under which the Upo wetland formed.
The core is divided into four units on the basis of grain size
distribution, abundance of mottles and vertical color variation.
Unit 1 has undergone pedogenic processes, resulting in variably
weak to moderate soil profile development. Unit 1 paleosols are
regarded as synsedimentary soils of floodplain origin, and the
radiocarbon data suggest that the whole paleosol profile spans
the last 5790 years. The boundaries between the soil horizons
are not clear-cut, probably due to a repeated cycle of accumulation, denudation and soil-forming processes. The recurrence
of these processes initiated the development of the Upo wetland.
The lower boundary of Unit 2 lies at about 2300 14 C yr BP, the
beginning of the Subatlantic age in Korea. The lack of intense
soil formation and abundant clay content in Unit 2 indicate that
the geomorphologically stable wetland was developed around
the coring site at that time. This means that the depositional
environment changed from a floodplain to a stable, continuously
submerging wetland setting. An abrupt change in sediment textures was detected in Unit 3, which commenced formation around
1000-900 14 C yr BP, indicative of geological events such as inundations or inflows of slope-wash sediments. Anthropogenic
deforestation and plowing around the Upo wetland area might
have started at that time. В© 2005 Elsevier Ltd and INQUA. All
rights reserved.
1552 A comparison of late Quaternary forest changes in
New Caledonia and northeastern Australia
Stevenson J. and Hope G. Quaternary Research 2005 64/3 (372383)
A pollen record from Lake Xere Wapo, southeast New Caledonia,
is the longest continuous terrestrial record to be recovered from
the tropical southwest Pacific and reveals a series of millennial
scale changes in vegetation over the last 130,000 yr. A comparison of the Lake Xere Wapo record with the key northeast
Australian record of LynchвЂ™s Crater reveals regional patterns of
change. From 120,000 to 50,000 yr ago the vegetation around
Lake Xere Wapo alternated between rainforest and maquis with
fire an important disturbance factor. In the last 50,000 yr fire
is almost absent from the record and the vegetation assumes a
character unprecedented in the preceding 100,000 yr, dominated
by Dacrydium and Podocarpus pollen. The most compelling
aspect of the comparison with LynchвЂ™s Crater is that the muchdiscussed Araucaria decline at around 45,000 yr ago in northern
Queensland is matched by a similar decline in the Lake Xere
Wapo record. В© 2005 University of Washington. All rights
reserved.
Glacial landforms and sediments
1553 A complex subglacial clastic dyke swarm, SВґolheimajВЁokull, southern Iceland
Le Heron D.P. and Etienne J.L. Sedimentary Geology 2005 181/12 (25-37)
A complex network of clastic dykes dissects loosely consolidated Holocene sediments along the east flank of the proglacial
braid plain of SВґolheimajВЁokull, southern Iceland. The dykes comprise downward-bifurcating intrusions up to 0.5 m thick and
several metres in length and are intruded into glaciogenic deposits (sandy gravel, gravelly sand, interlaminated silt and sand, and
diamicton). The dykes were sourced from a clast-poor sandy
diamicton, interpreted as a subglacial till, and were intruded
downwards beneath SВґolheimajВЁokull glacier during a previous
phase of advance. As the glacier advanced southwards, it loaded
the sediment column resulting in the intrusion of dykes with
a consistent south-southwest dip (with rare northward-dipping
examples). The dyke fills are characterised by laminated sed-
iment, with laminae oriented parallel to the dyke margins and
comprise interlaminated clay, silty clay, silt, sand, sandy gravel
and diamicton. In some dykes, high concentrations of pebble- to
boulder-sized clasts occur in association with rotated pods of the
laminated sediment. The laminae are thought to have evolved
by a slow, long-lived intrusion process that involved the repeated
fracture and expansion of the host sediments followed by viscous
smearing-on of subglacial material onto the dyke walls, rather
than rapid injection of fluidised sediment. В© 2005 Elsevier B.V.
All rights reserved.
1554 3-D sedimentary architecture of a Quaternary gravel
delta (SW-Germany): Implications for hydrostratigraphy
Kostic B., Becht A. and Aigner T. Sedimentary Geology 2005
181/3-4 (147-171)
This paper investigates a Quaternary Gilbert-type gravel delta
that was formed in an ice-marginal environment at the end of
the last glacial period. Outcrop, sediment core and groundpenetrating radar (GPR) studies reveal the sedimentary facies
and depositional architecture of the delta that comprises three
major units: (1) a 2-5 m thick, gravelly topset with an erosional base, formed by accretion of bedload sheets in a braided
river; (2) an up to 40 m thick, steeply inclined (13-35В°) foreset,
dominated by gravelly lithofacies being the product of cohesionless debris flows and debris falls as well as gravity slides
while sandy lithofacies was deposited by traction currents; and
(3) a 10-20 m thick, sandy bottomset comprising low-density
turbidites. Syn- to postdepositional deformation of parts of the
bottomset deposits largely resulted from rapid deposition of overlying gravels and differential loading of the prograding foreset
beds. The development of the delta was most likely controlled
by a high sediment supply and lake level fluctuations. The overall coarsening-upward succession reflects delta progradation and
aggradation into a glaciolacustrine environment. Outcrop sedimentology served as a direct analogue in order to characterise
the three-dimensional sedimentary and hydraulic architecture of
the nearby gravel-delta aquifer. Applying a multidisciplinary
approach, sedimentological, geophysical, and hydrogeological
data were integrated within the 3-D modelling package Gocad
(Earth Decision Sciences) to develop high-resolution 3-D aquifer
models. В© 2005 Elsevier B.V. All rights reserved.
1555 Evolution of the southern Barents Sea framing in the
Late Pleistocene
Tarasov G.A. and Matishov G.G. Doklady Earth Sciences 2005
404/7 (1093-1096)
The Late Pleistocene was characterized by the growth and degradation of continental and, sometimes, marine ice sheets in
the Northern Hemisphere. These processes were responsible for
the main global changes that occurred on the continents and in
the ocean and atmosphere. The study region is a key one for
the study of unclear and controversial problems concerning the
reconstruction of deglaciation conditions and postglacial environmental changes. The present communication is based o n
results of the lithological study of the offshore borehole sections
of bays, shelf zones, and lacustrine depressions in the northern
Kola and Kanin peninsulas. We also used data from morphostructural and geomorphological observations, dendrochronological
analysis (Pinus silvestris), radiocarbon datings, 10 Be and 26 Al
isotopic datings in quartz-bearing rocks, and other materials.
The study region is large. Moreover, its geological-geomorphological structure and physicogeographic conditions sharply vary
from east to west. Therefore, it is reasonable to consider the main
natural peculiarities separately for each of the examined areas.
Copyright В© 2005 by Pleiades Publishing, Inc.
1556 Strandline analysis in the southern basin of glacial
Lake Agassiz, Minnesota and North and South Dakota, USA
Fisher T.G. Bulletin of the Geological Society of America 2005
117/11-12 (1481-1496)
Glacial Lake Agassiz, a large Pleistocene lake, left behind strandlines at multiple elevations within its basin. Prior researchers
have used these strandlines to identify four relatively stable water level stages, but tracing them over long distances is often
problematic. In this study, the elevation of the Tintah strandline
is returned to its original designation, and a newly interpreted
stable lake level at 1020-1030 ft (311-314 m) is referred to as
THE QUATERNARY
the Upham level, based on a concentration of ridges and a spit
at that elevation. Cores from strandline and lagoon complexes
from the Milnor to Tintah beaches reveal a decreasing thickness
of strandline sediment associated with shorter aggregate-length
strandlines. This relationship is most likely controlled by sediment starvation, greater water level fluctuations and shallower
water. Beaches near the head of the southern outlet spillway
indicate that shoreline occupation at the Lower Campbell level
was either very short-lived or strandline development was hampered by shallow water. The modern-day sill elevation between
the southern outlet spillway and the lake basin is found to be 3
km south of White Rock, Minnesota, at an elevation of 974 ft
(297 m). All but the Campbell strandlines at the southern outlet
are interpreted as the result of a regression driven by incision
of the southern outlet spillway. В© 2005 Geological Society of
America.
The Holocene
1557 Archaeological evidence for the first Mesolithic occupation of the Western Isles of Scotland
Gregory R.A., Murphy E.M., Church M.J. et al. Holocene 2005
15/7 (944-950)
The examination of eroding coastal dunes at the prehistoric site of
Northton, Harris, has produced the first archaeological evidence
of Mesolithic activity in the Western Isles in the form of two
midden-related deposits. The first phase of Mesolithic activity
is dated to 7060-6650 cal. BC based on AMS dating of charred
hazelnut shells. This discovery appears to validate the frequent
pollen-based inferences of Mesolithic impact for the area and, as
predicted, allows the Atlantic fringe of Scotland to become part
of the European Mesolithic mainstream. A detailed pedological
analysis also suggests that these early midden layers may have
been amended during the Neolithic period as part of a possible
phase of cultivation. В© 2005 Edward Arnold (Publishers) Ltd.
1558 Late-Holocene environmental variability at Munsa archaeological site, Uganda: A multicore, multiproxy approach
Lejju B.J., Taylor D. and Robertshaw P. Holocene 2005 15/7
(1044-1061)
Palaeoenvironmental data, in the form of 113 counts of pollen,
fungal spores and charcoal abundances, 121 counts of phytoliths
and 15 AMS 14 C dates (11 macrofossil and 4 bulk sediment samples), have provided a means of reconstructing the late-Holocene
environmental history of Munsa archaeological site, Uganda.
The data were extracted from sediment cores from what is today
a papyrus swamp, located within an area described by an outermost ring of earthworks at Munsa. Sediment core data indicate
the general presence of forested conditions to c. AD 1100, although there is evidence for the local presence of food plants prior
to this date. Deforestation from c. AD 1100 is marked in both
the pollen and phytolith records, while fungal spores indicate
the presence of increased numbers of herbivores post-deforestation. Indicators of deforestation and increased herbivore numbers
broadly accord with the archaeological evidence for substantial
occupation of the site at Munsa and the establishment of a mixed
economy based on crops, cattle and iron working. Evidence for
forest recovery and reduced herbivore numbers locally from c.
AD 1780 could reflect abandonment of permanent settlement at
the site, possibly during or following a period of drought and/or
political upheaval in the region. Fungal spores and phytoliths
provide evidence of agricultural activities at Munsa that have not
left an imprint on pollen records, thus supporting the case for
the use of multiproxies in palaeoenvironmental research, while
intercore differences between the three sediment cores analysed,
although relatively minor, confirm the benefits of a multicore approach. Tentative evidence for the very early presence of Musa
(cultivated edible banana) is provided and warrants further study.
В© 2005 Edward Arnold (Publishers) Ltd.
1559 Tephra-dated climate- and human-impact studies during the last 1500 years from a raised bog in Central Ireland
Hall V.A. and Mauquoy D. Holocene 2005 15/7 (1086-1093)
Historic Icelandic tephrochronology constrains the time frame
of a plant macrofossil and palynological study of ombrotrophic
295
peat to evaluate the effects of climatic and human impact over
the last 1500 years on the landscape at a large monastic site in
the Irish Midlands. The plant macrofossil climate proxy record
indicates maximum wetness during the sixth century AD. Decreasing wetness occurred from the late ninth century to the late
thirteenth century. From c. AD 1290 to 1830, the plant macrofossils record a reduction in mire surface wetness and there is no
evidence for вЂ�Little Ice AgeвЂ™ climatic deteriorations. The pollen
analytical evidence indicates an agricultural system dominated
by pastoralism throughout the first millennium AD with arable
agriculture increasing in the closing years of the first millennium
and throughout the second millennium AD. From the eighteenth
century onward, agricultural land use expands with a concomitant
reduction in scrub. В© 2005 Edward Arnold (Publishers) Ltd.
1560 An evaluation of multielement analysis of historic soil
contamination to differentiate space use and former function
in and around abandoned farms
Wilson C.A., Davidson D.A. and Cresser M.S. Holocene 2005
15/7 (1094-1099)
Historic and prehistoric human activity can cause accumulation
of elements in the soil. Multielement soil analysis has been used
extensively over the last two decades to study element patterns
of historic soil enrichment as a means of prospecting for sites
and as an aid to interpretation of space use within archaeological
structures. However, there have been surprisingly few of studies
designed to assist with the interpretation of the analytical results. In this investigation soils from six abandoned farms with a
known history of spatial use were sampled to determine if similar
patterns of trace element enhancement occur between different
farms. The preliminary results show significant differences in
soil elemental concentrations between the functional areas, and
highlight similar patterns of element enhancement between the
farms. Concentrations of Ca, P, Sr, Ba, Zn and Pb are elevated
in the buildings and fields of all the farms and provide valuable
information about past human activity. В© 2005 Edward Arnold
(Publishers) Ltd.
1561 High-resolution reconstruction of a 1300 year old gully
system in northern Bavaria, Germany: A basis for modelling
long-term human-induced landscape evolution
Dotterweich M. Holocene 2005 15/7 (994-1005)
Knowledge of historical gullying and long-term processes of
interactions between land use and gullying is still rather limited. Here, I review results from case studies in Germany and
neighbouring countries and exmine the complex development of
a gully system in northern Bavaria, integrating land-use changes
and their interactions within a conceptual model. Reconstructions of gully development were made by identifying and dating
sediment layers, artificial modifications and soil horizons at high
spatial and temporal resolution, combined with analyses of historical documents. The case study in northern Bavaria shows
that more than 150 colluvial layers found in a gully system revealed the detailed history of gully development during the last
1300 years. The first gullying took place in early Mediaeval
times during several heavy rainfall events but the main phases
of gullying took place between the fourteenth and the mid-eighteenth centuries. Occurrence of gullying was strongly linked to
phases of high land-use intensity, which later changed the runoff
pattern and enlarged the catchment area by 50%. Subsequently,
overflowing field furrows led to the development of two gullies,
up to 6 m deep, in late Mediaeval and early modern times. From
the middle of the nineteenth century until today, only a little
soil erosion has taken place and most of the catchment area has
become grassland or forest. During the 1050 years from AD 800
to 1850, a soil volume of about 6430 m3 was eroded by gullying,
destroying 15% of the arable land. The results provide a basis
for modelling long-term human-induced landscape evolution. В©
2005 Edward Arnold (Publishers) Ltd.
296
THE QUATERNARY
1562 A new step towards a synthesis of the Holocene
history of the vegetation of the Monts de la Madeleine,
Forez Livradois and Pilat (Eastern Massif central, France)
(French) (LвЂ™Вґevolution Holocène de la vВґegВґetation des monts de
la Madeleine, du Forez, du livradois et du pilat (Massif central
oriental, France): LвЂ™apport dвЂ™une nouvelle sВґerie dвЂ™analyses
palynologiques)
Argant J. and Cubizolle H. Quaternaire 2005 16/2 (119-142)
In France, many fens and peat bogs are located in the granitic
eastern part of the Massif central. In this area peat formation
was determined by the climate with abundant rainfalls - from
1000 to 1500 mm above an altitude of 1000 m a.s.l. - a fair
distribution of this rainfalls over the year, the topography with
shallow headwaters areas, small hollows with concave bottoms
and the geomorphology with glacial and periglacial land forms
and deposits. During the last sixty years several pollen analysies, discussed in that paper, allows the reconstruction of the
vegetation of this area back to the end of the Lateglacial. But
the most ancient studies are not so precise as those of today
and have often either few or even no radiocarbon dates. All
these studies have not been published. So, four new analysies
were undertaken on three peat bogs and one fen. They are supported by 32 14 C dates which allows us to be precise about the
former available data. They are part of global research including
palaeoenvironmental reconstruction, understanding the origin of
the great number of holocene mires and evaluation of the role
of Man in the landscape evolution since the prehistoric time.
Pollen analysis shows that the changes in vegetation are very
similar to what is known elsewhere in the Massif central, except
in the Massif du Pilat where the dynamics of Fagus and Abies
is quite different. Human influence can be noted since the end
of the Atlantic period (Middle Neolithic, about 5500 cal. BP)
and the numerous radiocarbon dates make it possible to have an
accurate chronology and they give us a better understanding of
the occupancy of the middle-range-mountain in the past.
1563 13 C variation of C3 and C4 plants across an Asian
monsoon rainfall gradient in arid northwestern China
Liu W., Feng X., Ning Y. et al. Global Change Biology 2005
11/7 (1094-1100)
We have investigated carbon isotopic compositions of four plant
genus/species, Bothriochloa ischaemum (C4 ), Stipa bungeana (C
3 ), Lespedeza sp. (C3 ) and Heteropappus less (C 3 ), along a
precipitation gradient in northwest China in order to assess the
impact of water availability on the carbon isotopic discrimination against 13 C during carbon assimilation in this area. This
information is necessary for reconstruction of paleovegetation,
particularly paleo-C 3 /C4 plant ratios using 13 C value of organic
matter in loess and paleosols in the Chinese Loess Plateau. The
13 C of C plants, as a group, exhibits a negative correlation with
3
the annual precipitation amount with a total change and sensitivity of 5%o and -1.1%o/100 mm, respectively, for the precipitation
range from 200 to 700mm. The C4 grass, B. ischaemum responds
to aridity by decreasing 1.7%o for over the precipitation range
from 350 to 700 mm; the plant 13 C is significantly correlated
with annual precipitation with a slope -0.61%o/100 mm. This
result implies that without considering the effect of water availability on the plant 13 C values, reconstruction of percent C4
vegetation during the last glaciation can be overestimated by
about a factor of two. В© 2005 Blackwell Publishing Ltd.
1564 Climate change and human impact on the Song Hong
(Red River) Delta, Vietnam, during the Holocene
Li Z., Saito Y., Matsumoto E. et al. Quaternary International
2005 144/1 (4-28)
On the basis of the results of palynological research on two cores
from the Song Hong (Red River) delta in the sub-tropical zone of
Asia, centennial- to millennial-scale climate changes and human
impacts during the Holocene were clarified. Three cycles of
cooling and warming were identified during the last 5000 yr: a
cool and wet climate during 4530-3340 cal. yr BP, 2100-1540
cal. yr BP, and 620-130 cal. yr BP, a warm and dry climate during
3340-2100 cal. yr BP, 1540-620 cal. yr BP and the present warm
climate. The first and last cooling events correspond to global
Holocene cooling events, the Neoglacial Period and the Little
Ice Age, respectively. Each persisted for 500-1000 yr, and they
occurred at intervals of 1500-2000 yr. Pollen records also reflect
human impacts on this area, which intensified after 3340 cal. yr
BP when large quantities of cultivated Gramineae taxa, possibly
including the main wet rice species, Oryza sativa, secondary
forest, and other upland cultivated taxa appear in the record. В©
2005 Elsevier Ltd and INQUA. All rights reserved.
1565 Quantification strategies for human-induced and natural hydrological changes in wetland vegetation, southern
Florida, USA
Donders T.H., Wagner F. and Visscher H. Quaternary Research
2005 64/3 (333-342)
An accurately dated peat profile from a mixed cypress swamp
in the Fakahatchee Strand Preserve State Park (FSPSP, Florida,
USA) has been examined for pollen and spores. The near-annual
resolved pollen record shows a gradual shift from a wet to a
relatively dry assemblage during the past 100 years. Timing
of drainage activities in the region is accurately reflected by the
onset and duration of vegetation change in the swamp. The reconstructed vegetation record has been statistically related to pollen
assemblages from surface sediment samples. The response range
of the FSPSP wetland to environmental perturbations could thus
be determined and this allows better understanding of naturally
occurring vegetation changes. In addition, the human impact
on Florida wetlands becomes increasingly apparent. Superimposed high-frequency variation in the record suggests a positive
correlation between winter-precipitation and pollen productivity of the dominant tree taxa. However, further high-resolution
analysis is needed to confirm this relation. The response range
of the FSPSP wetland to environmental perturbations on both
annual- and decadal-scales documented in this study allows recognition and quantification of natural hydrological changes in
older deposits from southwest Florida. The strong link between
local hydrology and the El NiЛњno Southern Oscillation makes the
palynological record from FSPSP highly relevant for studying
past El NiЛњno - variability. В© 2005 University of Washington. All
rights reserved.
1566 The stratigraphy and fire history of the Kutai Peatlands, Kalimantan, Indonesia
Hope G., Chokkalingam U. and Anwar S. Quaternary Research
2005 64/3 (407-417)
The equatorial peatlands of the Kutai lowland of eastern Kalimantan are generally 4-10 m in thickness but some sections exceed
16 m in depth. The deposition of peat commenced about 8000
yrs ago after shallow flooding of the basin by the Mahakam River.
The earliest vegetation is a Pandanus swamp which grades upwards to swamp forest dominated by dipterocarps. The peatland
has expanded laterally and rivers have maintained narrow leveechannel tracks through the swamp, which has grown vertically in
balance with river accretion. Historical fires are associated with
extreme El NiЛњno years of drought, but human agency is important.
The fires of 1982-1983 and 1997-1998 burnt up to 85% of the
vegetation on the peatland. Although charcoal analyses show
that fire has occurred throughout the history of the peatland, it
is rare in forests remote from rivers until the last 3000 years and
only common within the last millennium. Fires are earlier and
more frequent in sites accessible from waterways, and floodplains
have been widely burnt down to water table or below, forming
extensive lakes. В© 2005 University of Washington. All rights
reserved.
1567 Vegetation change in the coastal-lowland rainforest at
AvaiвЂ™oвЂ™vuna Swamp, VavaвЂ™u, Kingdom of Tonga
Fall P.L. Quaternary Research 2005 64/3 (451-459)
AvaiвЂ™oвЂ™vuna Swamp, a small coastal wetland in VavaвЂ™u, Kingdom of Tonga, produced a 4500-year pollen and sediment record.
Results are: (1) a mid-Holocene sea level highstand is confirmed
for Tonga between about 4500 and 2600 14 C yr B.P.; marine clay
contains pollen from mangroves (Rhizophora mangle), coastal
forest trees (Barringtonia asiatica and Cocos nucifera), and rainforest trees (Alphitonia, Rhus, Hedycarya and Calophyllum).
(2) Microscopic charcoal first appeared at 2600 14 C yr B.P., coincident with the arrival of Polynesians. (3) Cocos, Pandanus,
Excoecaria, Macaranga, and Elaeocarpaceae pollen reflects the
establishment of a mixed coastal-lowland rainforest in the last
2500 years. (4) The loss of Hedycarya, Elaeocarpus, Calophyl-
THE QUATERNARY
lum, and Guettarda and the reduction of Terminalia and taxa in
the Papilionaceae family by about 1000 years ago may be due
to habitat destruction and the loss of dispersal capabilities of
some species through the extinction of the two largest pigeons in
Tonga. В© 2005 University of Washington. All rights reserved.
1568 Cultivation and human impact at 6000 cal yr B.P. in
tropical lowland forest at Niah, Sarawak, Malaysian Borneo
Hunt C.O. and Rushworth G. Quaternary Research 2005 64/3
(460-468)
This paper describes palynological evidence for what appears to
be comparatively large-scale human impact in the catchment of
the Sungai Niah in the wet tropical lowland swamp forests of
Sarawak, Malaysian Borneo close to the Great Cave of Niah.
Pollen associated with cleared landscapes and rice cultivation is
evident in the sedimentary record from before 6000 cal yr B.P.
Human activity seems to have been associated with changes in
sedimentary regime, with peat-dominated environments being
replaced diachronously by clay-dominated deposition. This may
reflect anthropogenic soil erosion in the catchment of the Sungai
Niah. В© 2005 University of Washington. All rights reserved.
1569 Holocene dryness and human occupation in Brazil during the "Archaic Gap"
Araujo A.G.M., Neves W.A., PilВґo L.B. and Atui J.P.V. Quaternary Research 2005 64/3 (298-307)
An overview of the archaeological data produced over the last
decades for Brazil, coupled with a background of recent paleoenvironmental studies, suggests that during the mid-Holocene vast
areas of Central Brazil ceased to be occupied by human groups.
Independent data from dated human skeletons, rock-shelter stratigraphy, and chronology of open-air sites converge to support
the inference that these areas were depopulated or altogether
abandoned. Paleoenvironmental data suggest that dryness events
constitute the major cause behind the observed trends. This
phenomenon expands the already perceived notion that climatic
stresses had a major role in the shaping of human settlement patterns in marginal environments, such as deserts and high-altitude
settings. В© 2005 University of Washington. All rights reserved.
1570 Interactions between human activity, volcanic eruptions and vegetation during the Holocene at Garua and Numundo, West New Britain, PNG
Boyd W.E., Lentfer C.J. and Parr J. Quaternary Research 2005
64/3 (384-398)
This paper reviews recent fossil phytolith analysis from wet
tropical West New Britain (Papua New Guinea). The Holocene vegetation has been influenced by spatially and temporally
diverse patterns of both prehistoric human settlement and catastrophic volcanic events. We have hypothesized different landscape responses and recovery pathways to events during the last
six millennia. Phytolith sequences on the coastal lowlands, the
Willaumez Peninsula, and nearby island of Garua provide details of vegetational change and human interactions at different
landscape scales since c. 5900 cal yr B.P. During this period
four major volcanic eruptions (c. 5900, 3600, 1700 and 1400
cal yr B.P.) have disrupted the landscape. The evidence provides
detailed descriptions of temporal and spatial patterning in the
impacts and changes in the vegetation. In particular, vegetation
responded differently from one event to another, reflecting both
forest recovery from seed bank and shooting, and the influence
of prehistoric people on recovering vegetation. Furthermore,
after some events landscape recovery was moderately uniform,
while after others there was considerable landscape partitioning.
Although these differences largely relate to airfall tephra type,
distribution and magnitude, the partitioning is more strongly influenced by human activity. В© 2005 University of Washington.
All rights reserved.
Periglacial
1571 Pleistocene cryostructures and landslide at Petit-Bost
(southwestern France, 45В°N)
Bertran P. and Fabre R. Geomorphology 2005 71/3-4 (344-356)
297
Remnants of a Pleistocene landslide have been observed during
field investigations of Quaternary alluvial formations of the Isle
River at Petit-Bost, southwestern France. The main features of
the landslide-induced deformation give a good indication of its
size and depth. The surface of rupture is located in a 0.5 m thick,
very plastic mottled clay at the top of an alluvial gravel. The
clay is overlain by 1.7 m thick loamy colluvial deposits with a
polygonal net of bleached wedges that testify to past permafrost
conditions. The mechanical parameters used in stability calculations for the case of an infinite planar sliding surface, that fits
well the geomorphological data, are given by triaxial tests. Stability calculation indicates that the slope is very stable at present
and that rupture can only have occurred in fully unconsolidated
and undrained conditions. This likely happened during permafrost degradation and subsequent thawing of ice-rich soil layers.
Oedometric tests indicate post-sliding over-consolidation of the
clay. With regards to the debate on permafrost distribution in
France during the Pleistocene, this study gives support to a wide
extent of permafrost, at least to the latitude 45В°N southward, during the coldest periods. It also points out that frost-induced slope
instability may have played a major, but still underestimated, role
in many French regions north to this latitude. В© 2005 Elsevier
B.V. All rights reserved.
Glaciology
1572 Holocene glacier chronology of Valenzuela Valley,
Mendoza Andes, Argentina
Espizua L.E. Holocene 2005 15/7 (1079-1085)
Glacial geologic evidence and radiocarbon-dated glacial deposits
provide evidence of glacier fluctuations during the last 5 ka years
in the Andes. Radiocarbon-dated moraines, morphological and
stratigraphical studies permit the reconstruction of glacier fluctuations during the Holocene in the Valenzuela area of the Mendoza
Andes valley located at 35В°S, in the upper Rio Grande basin. The
Holocene record in this part of the Andes is mostly unknown,
so this research is relevant for palaeoclimatic reconstructions in
South America. In the Ro Valenzuela, glacier variations were
dated in the El Azufre and El PeЛњnoВґ n valleys. The first Neoglacial
advance occurred at c. 5700 yr BP and a very close re-advance
of similar magnitude occurred at 4700-4300 yr BP which formed
well-preserved lateral-terminal moraines. The first Neoglacial
advance occurred in the El PeЛњnoВґ n valley at c. 4400 yr BP and a
well-preserved terminal moraine is observed. A second Neoglacial advance reached its maxima at c. 2500-2200 yr BP in the El
Azufre and El PeЛњnoВґ n glaciers. A third, corresponding to the вЂ�ittle
Ice AgeвЂ™, culminated at c. 400 yr BP (c. AD 1451-1641 cal. yr)
and 350 60 yr BP (c. AD 1460-1644 cal. yr) in the El Azufre
valley. The third Neoglacial advance is distinguished in the
El PeЛњnoВґ n valley based on morphological characteristics, colour,
freshness of the glacial deposits and the proximity to the active
glacier. It is indicated by the Amarilla I, II, III lateral moraines.
An estimation of the magnitude of snowline depression is obtained comparing the altitude of the present snowline with that
of the reconstructed snow line for the first Neoglacial and вЂ�Little
Ice AgeвЂ™ advances. В© 2005 Edward Arnold (Publishers) Ltd.
1573 An alternative form for the statistical distribution of
extreme avalanche runout distances
Keylock C.J. Cold Regions Science and Technology 2005 42/3
(185-193)
There are two main approaches in the avalanche literature for the
statistical characterisation of extreme avalanche runout and these
are known as the alpha-beta and runout ratio methods. Recent
work suggests that the latter method is a more robust approach.
This paper examines the statistical reasoning behind the selection of the Extreme Value Type I or Gumbel distribution used to
characterise the runout distribution in the runout ratio method.
On the basis that a threshold is often applied to the distribution of extreme avalanches used in analysis, it is proposed that
the Generalised Pareto Distribution is an appropriate candidate
distribution based on theoretical arguments. Such a proposal is
tested against data on extreme avalanches in Iceland for both
the largest events on specific paths and for all events exceeding
a threshold. The latter is a peaks-over-threshold approach that
298
THE QUATERNARY
potentially allows more robust distribution estimation due to the
increase in data availability. В© 2005 Elsevier B.V. All rights
reserved.
1574 Greenland mass balance from GRACE
Velicogna I. and Wahr J. Geophysical Research Letters 2005
32/18 (1-4)
We use 22 monthly GRACE (Gravity Recovery and Climate Experiment) gravity fields to estimate the linear trend in Greenland
ice mass during 2002-2004. We recover a decrease in total ice
mass of 82 28 km3 of ice per year, consistent with estimates
from other techniques. Our uncertainty estimate is dominated
by the effects of GRACE measurement errors and errors in our
post glacial rebound (PG) correction. The main advantages of
GRACE are that it is sensitive to the entire ice sheet, and that
it provides mass estimates with only minimal use of supporting
physical assumptions or ancillary data. Copyright 2005 by the
American Geophysical Union.
1575 A user-friendly anisotropic flow law for ice-sheet
modelling
Gillet- Chaulet F., Gagliardini O., Meyssonnier J. et al. Journal
of Glaciology 2005 51/172 (3-14)
For accurate ice-sheet flow modelling, the anisotropic behaviour
of ice must be taken fully into account. However, physically
based micro-macro ( -M) models for the behaviour of an anisotropic ice polycrystal are too complex to be implemented easily in
large-scale ice-sheet flow models. An easy and efficient method
to remedy this is presented. Polar ice is assumed to behave as
a linearly viscous orthotropic material whose general flow law
(GOLF) depends on six parameters, and its orthotropic fabric
is described by an вЂ�orientation distribution functionвЂ™ (ODF) depending on two parameters. A method to pass from the ODF to
a discrete description of the fabric, and vice versa, is presented.
Considering any available -M model, the parameters of the
GOLF that fit the response obtained by running this -M model
are calculated for any set of ODF parameters. It is thus possible
to tabulate the GOLF over a grid in the space of the ODF parameters. This step is performed once and for all. Ice-sheet flow
models need the general form of the GOLF to be implemented
in the available code (once), then, during each individual run, to
retrieve the GOLF parameters from the table by interpolation. As
an application example, the GOLF is tabulated using three different -M models and used to derive the rheological properties
of ice along the Greenland Icecore Project (GRIP) ice core.
1576 A distributed surface energy-balance model for complex topography and its application to StorglaciВЁaren, Sweden
Hock R. and Holmgren B. Journal of Glaciology 2005 51/172
(25-36)
A grid-based surface energy-balance mass-balance model has
been developed to simulate snow- and ice melt in mountainous
regions with an hourly resolution. The model is applied to StorglaciВЁaren, a valley glacier in Sweden, using a 30m resolution
digital elevation model. Emphasis is directed towards computing
the radiation components. These are modelled individually, considering the effects of slope angle, aspect and effective horizon.
A new parameterization for snow albedo is suggested, modifying the albedo of the preceding hour as a function of time after
snowfall, air temperature and cloudiness. The model is used to
provide the meltwater input for discharge modelling and to assess
the influence of the individual components on melt. Results are
validated by means of observed melt rates, patterns of snow-line
retreat and proglacial discharge. In general, simulations are in
good agreement with observations. In particular, the diurnal and
seasonal fluctuations of discharge are simulated remarkably well.
1577 Spatial and temporal evolution of rapid basal sliding
on Bench Glacier, Alaska, USA
Macgregor K.R., Riihimaki C.A. and Anderson R.S. Journal of
Glaciology 2005 51/172 (49-63)
We measured the surface velocity field during the summers of
1999 and 2000 on the 7 km long, 185 m thick Bench Glacier,
Alaska, USA. In the spring of both years, a short-lived pulse of
surface velocity, 2-4 times the annual mean velocity, propagated
up-glacier from the terminus at a rate of 200-250 md-1 . Displacement attributable to rapid sliding is 5-10% of the annual
surface motion, while the high-velocity event comprised 60-95%
of annual basal motion. Sliding during the propagating speed-up
event peaked at 6-14cmd-1 , with the highest rates in mid-glacier.
Continuous horizontal and vertical GPS measurements at one
stake showed divergence and then convergence of the ice surface
with the bed as the velocity wave passed, with maximum surface
uplift of 8-16 cm. High divergence rates coincided with high horizontal velocities, suggesting rapid sliding on the up-glacier side
of bedrock steps. Initiation of the annual speed-up event occurred
during the peak in englacial water storage, while the glacier was
entirely snow-covered. Basal motion during the propagating
speed-up event enlarges cavities and connections among them,
driving a transition from a poorly connected hydrologic system
to a well-connected linked-cavity system. Sliding is probably
halted by the development of a conduit system.
1578 Borehole imagery of meteoric and marine ice layers in
the Amery Ice Shelf, East Antarctica
Craven M., Carsey F., Behar A. et al. Journal of Glaciology 2005
51/172 (75-84)
A real-time video camera probe was deployed in a hot-water
drilled borehole through the Amery Ice Shelf, East Antarctica,
where a total ice thickness of 480 m included at least 200 m of
basal marine ice. Down-looking and side-looking digital video
footage showed a striking transition from white bubbly meteoric
ice above to dark marine ice below, but the transition was neither
microscopically sharp nor flat, indicating the uneven nature (at
centimetre scale) of the ice-shelf base upstream where the marine ice first started to accrete. Marine ice features were imaged
including platelet structures, cell inclusions, entrained particles,
and the interface with sea water at the base. The cells are assumed
to be entrained sea water, and were present throughout the lower
100-150 m of the marine ice column, becoming larger and more
prevalent as the lower surface was approached until, near the
base, they became channels large enough that the camera field of
view could not contain them. Platelets in the marine ice at depth
appeared to be as large as 1-2 cm in diameter. Particles were
visible in the borehole meltwater; probably marine and mineral
particles liberated by the drill, but their distribution varied with
depth.
1579 Use of the ELA as a practical method of monitoring
glacier response to climate in New ZealandвЂ™s Southern Alps
Chinn T.J., Heydenrych C. and Salinger M.J. Journal of Glaciology 2005 51/172 (85-95)
In lieu of direct glacier surface mass-balance measurements,
equilibrium-line altitudes (ELAs) have been measured over a 28
year period at 50 selected glaciers distributed along the glacierized length of New ZealandвЂ™s Southern Alps. Analysis of the data
shows that ELAs are a useful measurement of glacier response
to annual climate fluctuations, although there is much variability
in the degree of response between glaciers in any given year.
Comparisons of individual glacier annual ELA with the mean
for all annual ELAs of the Southern Alps show a large variation of individual glacier response, with coefficients of variation
(r2 ) ranging from 0.53 to 0.90. The ELA data show detailed,
but qualitative, annual mass-balance variations on both regional
and individual glacier scales. The ELA record closely predicts
glacier termini responses that follow after appropriate response
time delays. The recorded variability in climate response for the
Southern Alps suggests no single glacier is truly representative
for detailed studies of glacier-climate relationships, and that a
large number of ELA measurements may be as good an indicator of climate as a few mass-balance measurements. Given the
appropriate mass-balance gradient, mass-balance values may be
calculated for any of the monitored glaciers.
1580 Ice-elevation changes of Glaciar Chico, southern Patagonia, using ASTER DEMs, aerial photographs and GPS
data
Rivera A., Casassa G., Bamber J. and KВЁaaВЁ b A. Journal of Glaciology 2005 51/172 (105-112)
Hielo PatagВґonico Sur (HPS; southern Patagonia icefield) is the
largest temperate ice mass at mid-latitudes in the Southern Hemisphere. With few exceptions, the glaciers in this region have been
retreating during the last 50 years. Based on field data, vertical
THE QUATERNARY
aerial photographs and satellite images, ice-elevation changes
since 1975 on Glaciar Chico, one of the main tongues of HPS,
are presented. A maximum ice thinning of 5.4 0.55 ma-1 was
observed at the glacier front between 1975 and 1997. Global positioning system (GPS) data were used in the accumulation area
of the glacier to infer a thinning rate of 1.9 0.14ma-1 between
1998 and 2001. This thinning rate is three times higher than the
snow accumulation rate estimated for that part of the glacier. A
mean net glacier mass balance of -0.29 0.097 km3 w.e. a-1
was estimated between 1975 and 2001. Climate data suggest an
increase in temperature and a reduction in precipitation during
most of the 20th century in the vicinity of HPS. Although these
climate changes are the primary explanation for the observed
ice-elevation changes of the glacier, ice-dynamics effects are
also believed to play an important role.
1581 Spatial and temporal variability of snow accumulation
in East Antarctica from traverse data
Frezzotti M., Pourchet M., Flora O. et al. Journal of Glaciology
2005 51/172 (113-124)
Recent snow accumulation rate is a key quantity for ice-core
and mass-balance studies. Several accumulation measurement
methods (stake farm, fin core, snow-radar profiling, surface morphology, remote sensing) were used, compared and integrated at
eight sites along a transect from Terra Nova Bay to Dome C, East
Antarctica, to provide information about the spatial and temporal
variability of snow accumulation. Thirty-nine cores were dated
by identifying tritium/ marker levels (1965-66) and non-seasalt (nss) SO 24 spikes of the Tambora (Indonesia) volcanic event
(1816) in order to provide information on temporal variability.
Cores were linked by snow radar and global positioning system
surveys to provide detailed information on spatial variability in
snow accumulation. Stake-farm and ice-core accumulation rates
are observed to differ significantly, but isochrones (snow radar)
correlate well with ice-core derived accumulation. The accumulation/ablation pattern from stake measurements suggests that
the annual local noise (metre scale) in snow accumulation can
approach 2 years of ablation and more than four times the average
annual accumulation, with no accumulation or ablation for a 5
year period in up to 40% of cases. The spatial variability of
snow accumulation at the kilometre scale is one order of magnitude higher than temporal variability at the multi-decadal/secular
scale. Stake measurements and firn cores at Dome C confirm
an approximate 30% increase in accumulation over the last two
centuries, with respect to the average over the last 5000 years.
1582 Dissipated work, stability and the internal flow structure of granular snow avalanches
Bartelt P., Buser O. and Kern M. Journal of Glaciology 2005
51/172 (125-138)
We derive work dissipation functional for granular snow avalanches flowing in simple shear. Our intent is to apply constructive theorems of non-equilibrium thermodynamics to the snow
avalanche problem. Snow chute experiments show that a bilayer system consisting of a non-yielded flow plug overriding a
sheared fluidized layer can be used to model avalanche flow. We
show that for this type of constitutive behaviour the dissipation
functionals are minimum at steady state with respect to variations
in internal velocity; however, the functionals must be constrained
by subsidiary mass-continuity integrals before the equivalence of
momentum balance and minimal work dissipation can be established. Constitutive models that do not satisfy this equivalence
are henceforth excluded from our consideration. Fluctuations
in plug and slip velocity depend on the roughness of the flow
surface and viscosity of the granular system. We speculate that
this property explains the transition from flowing avalanches
to powder avalanches. Because the temperature can safely be
assumed constant, we demonstrate within the context of nonequilibrium thermodynamics that granular snow avalanches are
irreversible, dissipative systems, minimizing - in space - entropy
production. Furthermore, entropy production is linear both near
and far from steady-state non-equilibrium because of the masscontinuity constraint. Finally, we derive thermodynamic forces
and conjugate fluxes as well as expressing the corresponding phenomenological Onsager coefficients in terms of the constitutive
parameters.
299
1583 Debris transport in a temperate valley glacier: Haut
Glacier dвЂ™Arolla, Valais, Switzerland
Goodsell B., Hambrey M.J. and Classer N.F. Journal of Glaciology 2005 51/172 (139-146)
This paper considers the role of structural glaciology in debris
entrainment, transport and deposition at Haut Glacier dвЂ™Arolla,
a temperate valley glacier in Valais, Switzerland. Sedimentological descriptions and clast analysis have been used to identify
relationships between ice structure and debris transport. Relationships identified are (1) debris associated with crevasse traces,
(2) the folding of rockfall material incorporated within primary
stratification to form medial moraines and (3) dirt cones and englacial debris layers associated with reactivated crevasse traces.
A conceptual model is introduced to summarize the manner in
which ice structures at Haut Glacier dвЂ™Arolla control entrainment
and deposition of debris.
1584 Decadal-scale variations in ice flow along Whillans Ice
Stream and its tributaries, West Antarctica
Stearns L.A., Jezek K.C. and Van Der Veen C.J. Journal of Glaciology 2005 51/172 (147-157)
We investigate velocity changes occurring along Whillans Ice
Stream (WIS) by comparing velocities derived from repeat aerial
photographs acquired in 1985-89 (average date of 1987) to interferometric satellite radar (InSAR) velocities collected in 1997.
Three different analysis methods are applied to the velocity data.
First, temporal and spatial changes in velocities are correlated to
identifiable features (flowlines, shear margins, bed features) visible on the 1997 RADARSAT Antarctic Mapping Project mosaic.
Second, we relate velocity gradients to stresses via the flow law
and, along with surface topography and ice-thickness data, apply
the force-budget technique to determine the relative importance
of driving stress, side drag and basal drag over time. Finally, the
mass balance of the main part of WIS is determined for 1987
and 1997. Our results are consistent with previous studies that
show an overall deceleration resulting in downstream thickening
of the ice stream (Whillans and others, 2001; Joughin and others,
2002).
1585 Instruments and Methods A non-destructive method
for measuring the salinity and solid fraction of growing sea
ice in situ
Notz D., Wettlaufer J.S. and Worster M.G. Journal of Glaciology
2005 51/172 (159-166)
We describe an instrument developed to make in situ measurements of salinity and solid-fraction profiles in growing sea ice.
The vertical resolution of the measurements is up to a few millimeters, with a temporal resolution of up to fractions of a second.
The technique is based on impedance measurements between
platinum wires around which sea ice grows. Data obtained using
this instrument in laboratory experiments are in good agreement
with theoretical predictions. In a field test in the Arctic, the bulk
salinity of growing sea ice has been measured in situ throughout
the whole depth of the ice layer. The data are compared with bulk
salinities obtained from ice cores, and confirm the general understanding that the bulk salinity in ice-core studies is significantly
underestimated in the lower parts of the cores. The approach can
also be used in other glaciological applications and for general
studies of two-phase, two-component porous media.
1586 The retreat stages of Arve glacier between cluses bolt
and chamonix ombilic during the lateglacial (Arve Valley,
Haute-Savoie) (French) (Les stades de retrait du glacier de
lвЂ™Arve entre le verrou de cluses et lвЂ™ombilic de chamonix au
cours du tardiglaciaire (VallВґee de lвЂ™Arve, Haute-Savoie))
Coutterand S. and Nicoud G. Quaternaire 2005 16/2 (85-94)
This updated cartography of glacial deposits, especially the ablation moraines and the associated devices, such as kame terraces,
enables us to suggest a paleogeography more complete of the
various steps of the Tardiglaciaire deglaciation in the middle
Arve Valley. The two main stages during the retreat, namely
Magland and Le Fayet ones were subdivided into two subdivisions (Tour Noire and Pierre a` Voix), and four subdivisions,
- AmВґerands, Fayet dвЂ™en Haut, Fayet du Milieu and Fayet dвЂ™en
Bas -, respectively. One age based on the exposur e method
(Be10 ) performed on a crystalline erratic boulder of the Magland-
300
THE QUATERNARY
Tour Noire stage-the most downstream from those studied in the
Sallanches ombilic, yield 17540 50010 Be BP. On the basis of
the various glacial equilibrium line values and on 10 Be ages, a
correlation is suggested between our relative chronology and the
Grisons scale (Switzerland).
1587 Laboratory study of erosion processes in snow
avalanches
Barbolini M., Biancardi A., Cappabianca F. et al. Cold Regions
Science and Technology 2005 43/1-2 (1-9)
In order to better understand the mechanics of erosive processes
characteristic of snow avalanche flows, a series of laboratory
experiments were carried out. In these experiments a mass of
dry granular material was released in a channel with rectangular
cross-section. A part of the channel was covered with an erodible
layer. The experiments were recorded with a high-speed digital
camera and the interaction between the flowing material and the
erodible bed was studied using different colours for the two materials. The records allowed an extremely detailed high-frequency
visualisation of the phenomenon. Observations of the erosion
mechanisms as well as measurements of the erosion rates were
performed. The results of the experiments were analysed and
interpreted with respect to some theoretical erosion models from
the literature. В© 2005 Elsevier B.V. All rights reserved.
1588 Mathematical modeling of snow entrainment in avalanche motion
Eglit M.E. and Demidov K.S. Cold Regions Science and Technology 2005 43/1-2 (10-23)
The entrainment of snow plays an important role in snow avalanche dynamics. Various ways of incorporating the entrainment
effect into avalanche mathematical models are discussed in this
paper. The results of calculations using a variety of formulae
for the entrainment rate that have been proposed for bed erosion
by flows of various physical natures are presented. For various
studied entrainment laws it is found that in motion at a steep slope
the entrainment takes place in a frontal part of an avalanche. The
motion of an avalanche depends mainly on the total depth of the
entrainable snow layer and on the length of the entrainment zone,
but only weakly on the form of the entrainment law. However
the length of an entrainment zone depends on the values of the
coefficients entering the entrainment law. В© 2005 Elsevier B.V.
All rights reserved.
1589 On size and shape effects in snow fracture toughness
measurements
Sigrist C., Schweizer J., Schindler H.- J. and Dual J. Cold Regions
Science and Technology 2005 43/1-2 (24-35)
Dry snow slab avalanche release is preceded by two fracture mechanical processes: shear failure of a weak layer or an interface
within the snowpack, followed by tensile failure of the overlaying
slab. For a slope stability analysis based on fracture mechanics,
the fracture toughness of snow has to be known. The purpose
of this work was to evaluate snow fracture toughness in mode I,
to determine to what extent it is affected by the specimen size
and shape and to search for adequate correction methods. Edgecracked beam-shaped snow specimens cut from homogeneous
layers of naturally deposited snow were subjected to three-point
bending and cantilever beam tests. To describe the size dependence an empirical size effect law and the FAD (failure assessment
diagram) approach were explored. By comparing the three-point
bending with the cantilever beam tests a shape dependence of the
toughness was found. The fracture process zone was estimated
to be in the order of at least one centimetre. Due to the large
size of the fracture process zone a dependence of the toughness
on the specimen size has to be expected, as it is typical for nonlinear, quasi-brittle materials. Experiments with four different
specimen sizes clearly confirmed that toughness is size dependent, possibly up to the scale of a slab avalanche. Preliminary
results suggest that the actual fracture toughness might be twice
as large as the one determined experimentally. Therefore, size
correction functions will be essential to transform toughness data
of laboratory-scaled experiments to the scale relevant for snow
slope stability models. В© 2005 Elsevier B.V. All rights reserved.
1590 Two-dimensional mathematical and numerical model
for the dynamics of granular avalanches
De Toni S. and Scotton P. Cold Regions Science and Technology
2005 43/1-2 (36-48)
This paper considers a model that reproduces the dynamics of
snow avalanches from initiation to runout for a given terrain
topography and given the volume, shape and position of the
initial mass. According to the Savage-Hutter theory, the granular
avalanche is treated as an incompressible cohesionless continuum, which satisfies a Mohr-Coulomb yield criterion and with
a Coulomb-type friction law at the bottom. The internal and
bottom friction angles, and , are the only rheological parameters to be set. The balance laws of mass and momentum are
simplified imposing the "shallow water" assumption and then
averaged along the vertical direction. The momentum balance
along the direction normal to the bottom reduces to a hydrostatic
distribution of pressure in a form which includes the centrifugal
forces due to the curvature. The stress tensor is written in a
coordinate system independent of the topography and related to
the velocity vector. The numerical model is validated by laboratory experiments, performed at the Hydraulic Laboratory of the
University of Trento, and by comparing the simulation results
with data collected from the literature. The applicability of the
model to natural snow avalanches is discussed with reference to
observations on granular avalanches reported in the literature and
to the surveys carried out at the Lavina Granda and Spini Valley
avalanche sites in Trentino Province (Italy). В© 2005 Elsevier
B.V. All rights reserved.
1591 A low cost system for the estimation of concentration
and velocity profiles in rapid dry granular flows
Barbolini M., Biancardi A., Natale L. and Pagliardi M. Cold
Regions Science and Technology 2005 43/1-2 (49-61)
A series of laboratory experiments with granular material has
been carried out at the Hydraulic and Environmental Engineering Department of the University of Pavia (Italy). The aim was
to investigate the internal properties of fast moving dry granular flows, with particular attention paid to the measurements
of concentration and velocity profiles. A low-cost acquisition
system was built using a Pulnix digital camera and off-the-shelf
components and integrating only open-source software around
a GNU/Linux operating system. Different techniques for the
measurements of velocity and concentration profiles have been
proposed and tested. The flow regimes have been investigated
and a distinction between "front", "body" and "tail" of the moving
mass has been established in terms of the flow concentration. Additionally, a comparison with experimental results and theories
found in the literature has been outlined. В© 2005 Elsevier B.V.
All rights reserved.
1592 Application of the snow cover model SNOWPACK to
snow avalanche warning in Niseko, Japan
Nishimura K., Baba E., Hirashima H. and Lehning M. Cold
Regions Science and Technology 2005 43/1-2 (62-70)
We describe the use of the snow cover model SNOWPACK for
avalanche warning in Niseko, Japan. Input data was collected
from a newly installed meteorological station at 800 m a.s.l.
To verify the model output, snow pit observations were made
almost everyday during the winter 2002-2003. Ten dry snow
slab avalanches occurred during the observation period. Most of
them were released after a heavy storm and had fracture depths
of 40-60 cm. Pit observations revealed that the fracture layers in
the snowpack consisted of either graupel or stellar precipitation
particles without rime (70%) or faceted crystals (30%). Slab
layers consisted of precipitation or decomposing and fragmented
particles, which indicated that these avalanches occurred soon
after the snow deposition. Snow profiles simulated with SNOWPACK roughly agreed with the observed profiles. The model
reproduced faceted crystals on a crust that became the weak
layer and caused the avalanches on 14-16 February 2003. In
addition, air temperature, solar radiation, wind speed, and snow
depth in the study area were estimated for grid points with 50 m
spacing. This allowed to calculate for each grid point snow
properties such as grain type and density as well as the snow
stability index SI. The predictions agreed reasonably well with
the field observations. В© 2005 Elsevier B.V. All rights reserved.
THE QUATERNARY
1593 High-speed photography of fractures in weak snowpack layers
van Herwijnen A. and Jamieson B. Cold Regions Science and
Technology 2005 43/1-2 (71-82)
During the winters of 2002-2003 and 2003-2004, fractures in
weak snowpack layers were recorded with a portable digital highspeed camera in the Columbia Mountains of British Columbia,
Canada. Fractures were photographed at 250 frames per second
in 21 compression tests, four rutschblock tests, three cantilever
beam tests as well as on five skier-tested slopes. Theoretical
slab avalanche release models generally assume propagation of a
brittle shear fracture in an incompressible weak snowpack layer.
However, displacement measurements of markers placed in the
snow above the weak layer indicated that slope normal displacement (due to crushing of the weak layer) was directly caused by
the fracture in the weak layer and independent of slope angle,
whereas the slope parallel displacement following fracture was
probably dependent on slope angle. Furthermore, displacement
measurements from rows of markers placed in the snow above
weak layers resulted in fracture speed measurements ranging
from 17 to 26 m/s, in good agreement with the only other published fracture speed measurement known to the authors: 20 m/s.
В© 2005 Elsevier B.V. All rights reserved.
1594 Avalanche forecast using numerical weather prediction
in Indian Himalaya
Singh A., Srinivasan K. and Ganju A. Cold Regions Science and
Technology 2005 43/1-2 (83-92)
The integration of a nearest-neighbours method based avalanche
forecast model with a mesoscale weather forecast model (MM5)
has been attempted for avalanche forecasting in Indian Himalaya.
The MM5 model simulates weather parameters up to day-4 over
the entire western Himalaya. The paper describes the methodology of using MM5 model predictions and some empirical relations, to find the probability of avalanche occurrence up to day-4
at a spatial resolution of 5 km by applying the nearest-neighbours
method. The nearest-neighbours model uses Euclidean weighted
distance metric to find 10 nearest neighbours from the past data in
terms of snow and weather parameters. Based on the avalanche
occurrences associated with nearest-neighbours, an a priori probability of avalanche occurrence is derived. This approach has
been tested for forecasting of avalanches in Chowkibal-Tangdhar road axis in Indian western Himalaya. В© 2005 Elsevier B.V.
All rights reserved.
1595 Improvement of a numerical snow drift model and
field validation
Durand Y., GuyomarcвЂ™h G., MВґerindol L. and Corripio J.G. Cold
Regions Science and Technology 2005 43/1-2 (93-103)
For about 10 years, MВґetВґeo-France has developed and operated
a real time operational suite aimed at snowpack simulation and
avalanche risk forecasting: the numerical model chain SafranCrocus-Mepra (SCM). It presently includes only a crude formulation of snowdrift effects at large spatial scales (massif). This
paper presents the improvements to a snow drift module suited to
the SCM chain. The new version called SYTRON3 which aims
at an improved simulation of snow drift effects at smaller spatial
scales. It is coupled with the SCM environment, which provides
hourly meteorological conditions and snow forcing. The main
modifications concern the new parameterisation schemes, which
are more realistic and more physically based. The increased
number of vertical layers allows now to represent explicitly the
three modes of movement during snow drift: creep, saltation
and diffusion. The validation of this new version as well as
comparisons with the previous version are performed at the Col
du Lac Blanc test site (2700 m a.s.l., French Alps) by the use of
digital photographs and field observations. В© 2005 Elsevier B.V.
All rights reserved.
1596 Avalanche activity in an extreme maritime climate:
The application of classification trees for forecasting
Hendrikx J., Owens I., Carran W. and Carran A. Cold Regions
Science and Technology 2005 43/1-2 (104-116)
Classification trees were trained to determine periods of significant avalanche activity in terms of an avalanche day, based on
meteorological parameters for the Milford Road, Fiordland, New
301
Zealand. Using a 10 year data set of meteorological parameters
and over 1800 individual avalanche occurrences from the Transit
New Zealand Milford Road Avalanche Programme we have described and statistically explored this avalanche regime and the
relationship between storm and avalanche activity in this extreme
climatic region. The Milford Road is located in the south western
corner of New Zealand and is dominated by a maritime climate
delivering in excess of 8 m water equivalent per year in precipitation, while winter storms can deposit up to 2 m of snow in one
storm. As the avalanche climate is dominated by direct action
avalanching, the meteorological parameters up to a maximum of
72 h preceding a significant avalanche period were examined.
Standard meteorological parameters including air temperature,
air pressure, wind speed and direction, snow depth and precipitation were obtained from two automatic weather stations located
in the starting zone and at road level. These parameters as well as
two derived wind drift parameters were used as the variables for
predicting the avalanche days. Two 10 fold cross validated classification trees were created, and suggested for use in forecasting.
The classification tree with highest accuracy of 85% predicted
avalanche days less well at 79%. An alternative tree using only
wind speed and wind speed and precipitation combined in a temperature sensitive wind drift parameter resulted in a lower overall
accuracy of 78%, but permitted a higher rate of correct prediction
for avalanche days at 86%. The alternative, more conservative
tree also reduced the number of false negative cases (observed as
avalanche days, but predicted as non-avalanche days) from 31 to
20 at a cost of increasing the false positive or false alarm rate. В©
2005 Elsevier B.V. All rights reserved.
1597 Geomorphological evidence for variations of the North
Patagonian Icefield during the Holocene
Glasser N.F., Jansson K.N., Harrison S. and Rivera A. Geomorphology 2005 71/3-4 (263-277)
Elucidating the timing and extent of former glacier fluctuations
is important because of the palaeoclimatic inferences that can
be drawn from such studies. Here we present new geomorphological evidence of the patterns of glacier behaviour around
the North Patagonian Icefield during the Holocene. Mapping
is based on visual interpretation of Landsat 7 ETM+ and Terra
ASTER satellite images, including the contemporary glaciers, areas of ice-scoured bedrock, trimlines, glacial lineations, terminal
moraines, sandur and fluvial sediments, deltas and ice-contact
deposits and alluvial fans. Recession of the icefield is marked by
three distinct moraine sets. These moraine sets are interpreted
as marking terminal positions related to the "Little Ice Age" and
two preceding, but as yet undated, phases of Holocene glacier expansion. Large arcuate terminal moraines in front of three of the
western glaciers are interpreted as composite features, reflecting
topographic limits to glacier expansion, indicating that caution
is required in the interpretation of previous 14 C dates obtained
from these moraines. There are strong contrasts in the patterns
of glacier behaviour between the east and west sides of the North
Patagonian Icefield, which cannot be attributed simply to an
east/west differential in the rates of change of atmospheric temperature and precipitation. We argue here that glacier response to
first-order climate forcing is tempered by second-order controls
introduced by regional-scale topographic effects, notably glacier
drainage basin extent and area, topographic controls on glacier
snout morphology and differences in terminal environment (calving/non-calving) during glacier recession. В© 2005 Elsevier B.V.
All rights reserved.
1598 Dating of Little Ice Age glacier fluctuations in the tropical Andes: Charquini glaciers, Bolivia, 16В°S
Rabatel A., Jomelli V., Naveau P. et al. Comptes Rendus Geoscience 2005 337/15 (1311-1322)
Fluctuations of the Charquini glaciers (Cordillera Real, Bolivia)
have been reconstructed for the Little Ice Age (LIA) from a set
of 10 moraines extending below the present glacier termini. A
lichenometric method using the Rhizocarpon geographicum was
used to date the moraines and reconstruct the main glacier fluctuations over the period. The maximum glacier extent occurred
in the second half of the 17th century, followed by nearly continuous retreat with three interruptions during the 18th and the 19th
centuries, marked by stabilisation or minor advances. Results obtained in the Charquini area are first compared with other dating
302
SEDIMENTOLOGY
performed in the Peruvian Cordillera Blanca and then with the
fluctuations of documented glaciers in the Northern Hemisphere.
Glacier fluctuations along the tropical Andes (Bolivia and Peru)
were in phase during the LIA and the solar forcing appears to
be important during the period of glacier advance. Compared
with the Northern Hemisphere mid-latitudes, the major advance
observed on these glaciers during the first half of the 19th century
is not present in the tropical Andes. This discrepancy may be
due to regional scale climate variations. В© 2005 AcadВґemie de
sciences. Published by Elsevier SAS. All rights reserved.
1599 Ice-sheet extent of the Antarctic Peninsula region during the Last Glacial Maximum (LGM) - Insights from glacial
geomorphology
Heroy D.C. and Anderson J.B. Bulletin of the Geological Society
of America 2005 117/11-12 (1497-1512)
We present marine geological and geophysical data for the Antarctic Peninsula that call for a larger ice-sheet reconstruction
during the Last Glacial Maximum (LGM) than suggested by
previous studies. Such glacial reconstructions are important
for quantifying post-LGM sea-level rise and providing boundary
conditions for general circulation models. Megascale glacial lineations on the continental shelf surrounding Antarctica provide
documentation for grounded ice that was streaming. Swath bathymetry data (NBP02-01) reveal lineations in each of the major
glacial troughs, except for Smith Trough, which features grooves
and bedrock drumlins (0.5-3 km spacing, 1:20 elongation ratios)
on crystalline bedrock. We place the maximum extent of ice at
the seaward limit of the lineations, at or near (<10 km landward
of) the shelf break. The occurrence of line-sourced gullies at the
mouth of each glacial trough (except Vega Trough, Weddell Sea)
supports the interpretation of ice grounded at the shelf break.
Megascale glacial lineations imaged in this study and other areas surrounding Antarctica (including the Ross Sea, Pine Island
Bay) have a consistent morphology, with elongation ratios of
>80:1 and spacings of 200-600 m (mode of 300 m). In contrast,
lineations ("bundles"; Canals et al., 2000) in the Gerlache-Boyd
Trough exhibit larger spacing (1-5 km), and the upstream portions ( 7 km) are carved directly into bedrock rather than till, as
suggested by previously unpublished air gun ( 120 Hz) seismic
data. These features have yet to be dated; however, they are believed to have been active during the LGM. Radiocarbon dates in
glaciomarine sediments (foraminifera and organic matter) from
seven glacial troughs indicate that megascale glacial lineations
were formed during the LGM. Other geomorphic features, such
as the grounding zone wedge in the northwestern Weddell Sea,
formed when the ice sheet was retreating. The initial retreat of
the grounded ice from the outer shelf occurred by 18,500 cal yr
B.P. The inner shelf was mostly ice free by 13,000 cal yr B.P.
This is significantly earlier than numerical models, which suggest Antarctic deglaciation began at 12,000 cal yr B.P. This also
suggests the peninsula area contributed to global sea-level rise
associated with meltwater pulse (MWP) 1a. В© 2005 Geological
Society of America.
SEDIMENTOLOGY
Sediments and sedimentary
processes - physical properties
1600 Statistical and geostatistical features of streambed hydraulic conductivities in the Platte River, Nebraska
Chen X. Environmental Geology 2005 48/6 (693-701)
This paper presents streambed hydraulic conductivities of the
Platte River from south-central to eastern Nebraska. The hydraulic conductivities were determined from river channels using
permeameter tests. The vertical hydraulic conductivities (K v )
from seven test sites along this river in south-central Nebraska
belong to one statistical population. Its mean value is 40.2 m/d.
However, the vertical hydraulic conductivities along four transects of the Ashland test site in eastern Nebraska have lower mean
values, are statistically different from the K v values in south-central Nebraska, and belong to two different populations with mean
values of 20.7 and 9.1 m/d, respectively. Finer sediments carried
from the Loup River and Elkhorn River watersheds to the eastern
reach of the Platte River lowers the vertical hydraulic conductivity of the streambed. Correlation coefficients between water
depth and K v values along a test transect indicates a positive correlation - a larger K v usually occurs in the part of channel with
deeper water. Experimental variograms derived from the vertical
hydraulic conductivities for several transects across the channels of the Platte River show periodicity of spatial correlation,
which likely result from periodic variation of water depth across
the channels. The sandy to gravelly streambed contains very
local silt and clay layers; spatially continuous low-permeability
streambed was not observed in the river channels. The horizontal
hydraulic conductivities were larger than the vertical hydraulic
conductivities for the same test locations. В© Springer-Verlag
2005.
Sediments and sedimentary
processes - transport
1601 RRS Charles Darwin Cruise 126, 11 Mar-20 Mar 2001.
Piston coring of debris flows and turbidites west and south of
the Canary Islands
Masson D.G. Cruise Report of the Southampton Oceanography
Centre 2002 -/40 (15p)
The major cruise objective was to obtain sediment cores at various locations to the west and southwest of the Canary Islands
with the aims of: Sampling debris flow sediments in the Canary
and Saharan debris flows Obtaining dateable sediments immediately above and below the debris flow sediments Sampling
turbidite sediments associated with the debris flows Sampling
sediments on either flank of a sediment wave west of La Palma In
addition, it was planned to obtain seabed video footage, using
the SHRIMP towed camera station, at several localities where
downslope sediment transport was believed to be active at the
present day, and undertake some test deployments of the SOC
Scatterometer system. В©2003-2004 University of Southampton.
1602 Assessment of sediment yield of watersheds by reservoir survey and simulation modelling in Brazilian semiarid
environment
De AraВґujo J.C. and Knight D.W. IAHS-AISH Publication 2005
-/299 (124-130)
Reservoir survey is a reliable method for assessing sediment
yield, which is a major environmental issue concerning impacts
on water resources. The paper presents field surveys of one urban
and six rural watersheds located in the Brazilian semiarid region,
with a wide range of characteristics. Basin areas range from 3 to
1220 km2 ; reservoir capacity 0.5-126 Mm3 ; silting history 46-94
years; and hydrological regimes range from very dry "scrtЛњao"
to mild mountain and coastal regions. Sediment yield assessment consisted of topo-bathymetric reservoir surveys; volume
reduction computation; dry bulk density evaluation based on
core samples; and trap efficiency estimation. Results showed per
capita urban contribution to be 21 kg year-1 ; average sediment
yield to be 426 t km-2 year -1 ; and reservoir-volume reduction at
a rate of 2% per decade. The Hidrosed model was applied and
field data were used for its validation. Hidrosed showed good
agreement with field data, with Nash and Sutcliffe efficiency
coefficient 0.81 for Maner SDR formulation.
1603 A theoretical exploration of catchment-scale sediment
delivery
Lu H., Moran C.J. and Sivapalan M. Water Resources Research
2005 41/9 (1-15)
[1] This paper proposes a theoretical explanation of the variations of the sediment delivery ratio (SDR) versus catchment
area relationships and the complex patterns in the behavior of
sediment transfer processes at catchment scale. Taking into account the effects of erosion source types, deposition, and hydrological controls, we propose a simple conceptual model that
consists of two linear stores arranged in series: a hillslope store
that addresses transport to the nearest streams and a channel
store that addresses sediment routing in the channel network.
SEDIMENTOLOGY
The model identifies four dimensionless scaling factors, which
enable us to analyze a variety of effects on SDR estimation,
including (1) interacting processes of erosion sources and deposition, (2) different temporal averaging windows, and (3) catchment runoff response. We show that the interactions between
storm duration and hillslope/channel travel times are the major
controls of peak-value-based sediment delivery and its spatial
variations. The interplay between depositional timescales and
the travel/residence times determines the spatial variations of
total-volume-based SDR. In practical terms this parsimonious,
minimal complexity model could provide a sound physical basis
for diagnosing catchment to catchment variability of sediment
transport if the proposed scaling factors can be quantified using climatic and catchment properties. Copyright 2005 by the
American Geophysical Union.
1604 Estimating sediment budgets at the interface between
rivers and estuaries with application to the Sacramento-San
Joaquin River Delta
Wright S.A. and Schoellhamer D.H. Water Resources Research
2005 41/9 (1-17)
[1] Where rivers encounter estuaries, a transition zone develops
where riverine and tidal processes both affect sediment transport processes. One such transition zone is the Sacramento-San
Joaquin River Delta, a large, complex system where several rivers
meet to form an estuary (San Francisco Bay). Herein we present
the results of a detailed sediment budget for this river/estuary
transitional system. The primary regional goal of the study was
to measure sediment transport rates and pathways in the delta in
support of ecosystem restoration efforts. In addition to achieving this regional goal, the study has produced general methods
to collect, edit, and analyze (including error analysis) sediment
transport data at the interface of rivers and estuaries. Estimating
sediment budgets for these systems is difficult because of the
mixed nature of riverine versus tidal transport processes, the different timescales of transport in fluvial and tidal environments,
and the sheer complexity and size of systems such as the Sacramento-San Joaquin River Delta. Sediment budgets also require
error estimates in order to assess whether differences in inflows
and outflows, which could be small compared to overall fluxes,
are indeed distinguishable from zero. Over the 4 year period
of this study, water years 1999-2002, 6.6 0.9 Mt of sediment
entered the delta and 2.2
0.7 Mt exited, resulting in 4.4
1.1 Mt (67
17%) of deposition. The estimated deposition
rate corresponding to this mass of sediment compares favorably
with measured inorganic sediment accumulation on vegetated
wetlands in the delta.
1605 Transport of gravel and cobble on a mixed-sediment inner bank shoreline of a large inlet, Grays Harbor, Washington
Osborne P.D. Marine Geology 2005 224/1-4 (145-156)
Gravel and cobble transport measurements were obtained by particle tracing experiments from a mixed sand, gravel and cobble
beach at the head of a crenulate-shaped shoreline, Half Moon
Bay in Grays Harbor, Washington. The direct measurements
and results provide insight regarding the differential transport
of gravel and cobble sized material on mixed-sediment beaches.
The results are of relevance to the development of both predictive
formulae for coarse-grained sediment transport and guidance for
practical gravel and cobble beach design. Net alongshore transport of gravel and cobble is generally several times greater than
the net cross-shore transport at Half Moon Bay. Larger and
smaller particles both move preferentially alongshore; however,
smaller particles tend to move across-shore more than larger particles. Particle transport distance during a tidal cycle increases
with particle size (or mass) up to a point, beyond which the particle transport rate begins to decrease with increasing size. The
direct relationship between transport rate and particle size may
reflect the selective entrainment and the rejection (or overpassing)
of larger particles, which are more exposed to fluid forces on the
beach surface than smaller particles, which are sheltered within
the matrix of larger particles, as well as the higher susceptibility
to burial of smaller particles. The decrease in transport rate for
the largest sizes may reflect the limited competency of the fluid
forces to transport larger and heavier particles under the observed
conditions. The direct transport measurements are consistent
with the overall particle size and shape distributions observed
303
on this crenulate-shaped inner bank beach whereby the larger
and flatter particles have tended to outrun the smaller and more
spherical particles in the downdrift direction. В© 2005 Elsevier
B.V. All rights reserved.
1606 Estimates of Australian dust flux into New Zealand:
Quantifying the eastern Australian dust plume pathway using
trace element calibrated 210 Pb as a monitor
Marx S.K., Kamber B.S. and McGowan H.A. Earth and Planetary Science Letters 2005 239/3-4 (336-351)
Weekly average atmospheric 210 Pb flux data collected between
March 1989 and February 2001 are used to construct a record
of Australian dust incursions onto the west coast, South Island,
New Zealand. Dusts collected from New Zealand glaciers were
found to contain a mixture of local New Zealand and long range
Australian material, based on novel binary and tertiary mixing
models of their ultra trace element chemistries. Trace element
characteristics further allowed determination of the provenance
of the long range dust component within Australia to better than
200 km resolution. 210 Pb analyses of these chemically characterised dust samples show that activity is related to the percentage
of Australian dust in a linear fashion. However, 210 Pb activity of
Australian dusts collected in New Zealand is orders of magnitude greater than that measured in the alluvial sediments of the
provenance areas. Australian dusts collected in New Zealand
are also highly enriched in 210 Pb compared to dusts collected
in Australia. This shows that dust scavenges atmospheric 210 Pb
which can therefore be used as an effective tracer of long range
dust transport. Previously obtained average atmospheric 210 Pb
flux data can thus be converted into the first record of long range
Australian dust flux in New Zealand. Results show that the
average atmospheric concentration of Australian dust in New
Zealand is 5.3 g m-3 . There is a clear seasonality with the
highest concentrations occurring in autumn-winter, preceding
AustraliaвЂ™s major dust storm season, which occurs in winterspring. We propose that while meteorological factors control
the occurrence of major dust storms, the availability of sediment
in source areas is a major control on Australian dust flux in
New Zealand. Dust flux is greatest after seasonal river flows
when transport of extremely fine grained dust occurs. This is
followed by transport of larger particles in the more spectacular
winter-spring dust storms. Our results provide information on
the characteristics and seasonality of dust transport in the Australian region, which had previously been difficult to quantify by
other methods (e.g., satellite imagery). Results also attest to the
effectiveness of 210 Pb as a tracer in this region. В© 2005 Elsevier
B.V. All rights reserved.
1607 Process-based model linking pocket gopher (Thomomys bottae) activity to sediment transport and soil
thickness
Yoo K., Amundson R., Heimsath A.M. and Dietrich W.E. Geology 2005 33/11 (917-920)
Burrowing organisms assist in shaping earth surfaces and are simultaneously affected by the environment they inhabit; however,
a conceptual framework is not yet available to describe this feedback. We introduce a model that connects the population density
of soil-burrowing animals to sediment transport via energy. The
model, combined with available data from California hillslopes
where soil erosion is driven by pocket gophers (Thomomys bottae), suggests that a gopher annually expends 9 kJ of energy,
or 1% of reported burrowing energy expenditure, in generating
sediment transport. The model is used to evaluate the case that
gophers prefer to populate thicker soils. The results suggest that
this behavior may drastically dampen the spatial and temporal
variations of soil thickness and gopher populations, implying
that burrowing organisms may create landscapes distinct from
those affected by abiotic process. В© 2005 Geological Society of
America.
1608 Prograde Rayleigh wave particle motion
Tanimoto T. and Rivera L. Geophysical Journal International
2005 162/2 (399-405)
Fundamental mode Rayleigh waves generally show retrograde
particle motion at the surface of the Earth. If there exists a
thick sedimentary layer, however, reversal of the sign of vertical eigenfunction occurs near the surface, resulting in prograde
304
SEDIMENTOLOGY
Rayleigh-wave particle motion at the surface. We show that, for
structures similar to those found in the Los Angeles basin (with
thickness up to 8 km), surface prograde motion may occur within
the frequency band 0.05-0.3 Hz. Although it has been suggested
that the effect of gravity on waves in unconsolidated surface layer
may be important, partitioning of energy between the elatic and
gravitational energy shows that the gravitational energy is less
than 1 per cent and thus is not important. The phenomenon
is caused by elastic effects, mainly caused by extremely slow
shallow seismic velocities. Observation of prograde elliptical
particle motion may be difficult, however, because particle motion is largely horizontal and high microseismic noise exists in
the same frequency band. В© 2005 RAS.
1609 Sediment suspension dynamics and a new criterion for
the maintenance of turbulent suspensions
Leeder M.R., Gray T.E. and Alexander J. Sedimentology 2005
52/4 (683-691)
The vertical component of the turbulent flow acceleration term,
@ (u i u j - is used to determine the net positive vertical force that
may support a suspended sediment load. A dimensionless criterion, A, is proposed for the maintenance of suspension, defined
as the ratio of the maximum vertical turbulent stress to immersed
weight of the suspended load above a unit bed area. In order
that a suspension be maintained: A= (v 2 -)max /m( - / )g 1
where vвЂ™ is instantaneous vertical turbulent velocity, and are
solid and fluid densities, respectively and m is the suspended load
dry mass. The A criterion is dynamic, being a ratio of stresses
and is analogous in this respect to Shields dimensionless stress
criterion, , for the initiation of bedload motion. The new criterion is successful in predicting the maintenance of steady-state
suspended sediment transport in open channel shear flow and
deposition from non-uniform particulate density flows of wall jet
type. В© 2005 International Association of Sedimentologists.
1610 Sand grain threshold, in relation to bed вЂ�stress historyвЂ™:
An experimental study
Paphitis D. and Collins M.B. Sedimentology 2005 52/4 (827-838)
Besides particle size, density and shape, the erodibility of a
sediment bed depends also upon the exposure to prethreshold
velocities in the overlying flow. Such flow effectively rearranges
the grains (at and below the bed surface), causing them to become more resistant to subsequent erosion. The effects of the
вЂ�stress historyвЂ™, leading up to the critical condition for sediment
movement, are investigated for unidirectional flows generated in
a recirculating laboratory flume. The sediment beds investigated
consisted of cohesionless quartz sand grains, with mean grain
diameters of 0-194 mm (fine sand), 0-387 mm (medium sand)
and 0-774 mm (coarse sand), with narrow particle-size distributions. The critical (threshold) shear velocity (target value) for the
three beds was established, within 2-5 min of increasing the flow
from zero velocity. The subsequent experiments were performed
under prethreshold velocities at 70% (for 5, 10, 20, 40 and 80 min
exposure duration), 80% (for 5, 10, 20, 40 and 80 min exposure
duration), 90 and 95% (for 5, 10, 20, 40, 80 and 120 min exposure duration) of the target value. Following exposure to these
different prethreshold conditions, the flow was increased then
to reach actual critical conditions, within a period of 2-5 min.
The critical condition for the initiation of sediment movement
was established using visual observation (supplemented by video
recordings), according to the Yalin criterion. The results show
that if the exposure duration to prethreshold velocities remains
constant, then the critical shear velocity increases with increasing prethreshold velocity. Likewise, if the prethreshold velocity
remains constant, then the critical shear velocity increases with
increasing exposure duration. In some circumstances, the critical shear velocity was found to increase by as much as 27%.
An empirical formula is proposed to account for the exposure
correction to be applied to the critical shear velocities of sandsized sediment beds; this is prior to their inclusion into bedload
transport formulae, for an improved prediction of the magnitude
and nature of transport. В© 2005 International Association of
Sedimentologists.
1611 Bedload path length and point bar development in
gravel-bed river models
Pyrce R.S. and Ashmore P.E. Sedimentology 2005 52/4 (839-857)
Low-sinuosity meandering gravel-bed flume experiments were
employed to investigate spatial patterns of deposition, which
point to patterns of channel development related to the pool
and bar morphology. At channel-forming discharges, fluorescent bedload tracers indicate that deposition is typically focused
around the point bar apex, downstream of the apex (contributing
to downstream bar migration), and at the bar head/riffle surface.
Seven flume experimental runs illustrate a sequence of point bar
development related to the spatial patterns of tracer deposition,
and the related path length distribution. At early stages of bar
formation, transport is from the scour zone across the point bar
head to the bar apex and bar margin downstream of the apex. As
the point bar develops, bedload transport across the bar decreases,
as transport along the channel thalweg increases and sediment is
deposited along the bar margin. Deposition cells appear to move
from downstream to upstream of the bar apex as this sequence
of bar formation progresses. At low (non-channel-forming) discharges, transport occurs to the bar head/riffle surface with very
little material being transported to the apex region or point bar
interior. The implication is that there is an inherent connection
between the loci of particle deposition and point bar formation,
largely controlled by the morphology of the channel. В© 2005
International Association of Sedimentologists.
1612 Wind forces and related saltation transport
Leenders J.K., van Boxel J.H. and Sterk G. Geomorphology 2005
71/3-4 (357-372)
The effect of several wind characteristics on sand transport was
studied in three experiments in north Burkina Faso, West Africa.
The first experiment is used to analyse the relation between wind
speed and shear stress fluctuations across height. The second experiment is used to study the relation of these wind characteristics
with saltation transport for fourteen convective storms, registered
during the rainy seasons of 2002 and 2003. The effect of sampling
time is studied for two of these convective storms. The third
experiment relates the turbulent structures of four convective
storms to saltation transport. Wind speed measurements were
undertaken with two sonic anemometers and sediment transport
was measured by two saltiphones. The sampling frequency was
either 8 or 16 Hz. The sonic frame of reference was rotated
according to a triple rotation. Horizontal fluctuations showed a
(fairly) good correlation with height because the wind speed at
both sensors was affected by the same vortices. The correlation
coefficients ranged from 0.42 (when the distance between the
sensors was 1.75 m) to 0.92 (when the distance was 0.25 m).
The instantaneous ReynoldsвЂ™ stress had the weakest correlation
(correlation coefficient of 0.05 at 1.75 m between the sensors
and 0.56 at 0.25 m between the sensors), because the momentum
at 2 m above the soil surface is transported by different eddies
than those close to the ground. This also explains the fairly
good correlation coefficients between the horizontal components
of the wind and saltation compared to the poor correlations between instantaneous ReynoldsвЂ™ stress and saltation. An increase
in sampling time did not have much impact on these correlation
coefficients up to sampling periods of about 30 s. However, this
sampling interval would be too coarse to describe the vertical
wind component adequately. The classification of the moments
of shear stress into the turbulent structures, sweeps, ejections,
inward and outward interactions, showed that the mean saltation
flux is higher at sweeps and outward interactions than at ejections
and inward interactions. Also, saltation occurred more often during sweeps and outward interactions than during ejections and
inward interactions. В© 2005 Elsevier B.V. All rights reserved.
1613 Processes of soft-sediment clast formation in the intertidal zone
Knight J. Sedimentary Geology 2005 181/3-4 (207-214)
Muddy soft-sediment clasts found on the sandy beach at Formby
Point, north-west England, are formed by wave erosion of late
Holocene intertidal sediments that are exposed during summertime ridge and runnel development. Break-up processes of the
intertidal sediments are strongly controlled by pre-existing bedding and surface desiccation cracks. Erosion of the intertidal
sediments and formation of soft-sediment clasts contributes to
the provision of fines into this dominantly sandy environment,
but loss of the archaeologically significant Holocene intertidal
SEDIMENTOLOGY
sediments is a potentially important management issue along
this coast. В© 2005 Elsevier B.V. All rights reserved.
Sediments and sedimentary
processes - deposition
1614 Sediment and organic carbon focusing in the Shelikof
Strait, Alaska
Rember R. and Trefry J. Marine Geology 2005 224/1-4 (83-101)
Profiles of excess 210 Pb and 137 Cs in sediment cores were used
to determine sediment accumulation rates in Outer Cook Inlet
and the Shelikof Strait, Alaska. In Outer Cook Inlet and the
northern Shelikof Strait, sediment accumulation rates averaged
0.16 cm yr-1 and ranged from 0.10 to 0.21 cm yr-1 . In contrast, sediment accumulation rates were > 4 times higher in the
central and southern Shelikof Strait where the average was 0.68
cm yr-1 with a range of 0.46 to 0.94 cm yr -1 . In addition to
higher rates of sedimentation, higher activities of excess 210 Pb
and higher levels of silt + clay, total organic carbon, Pb and
Mn also were found in surface sediments from the central and
southern Shelikof Strait relative to Outer Cook Inlet and the
northern Shelikof Strait. These trends are directly related to the
progressive sorting and focusing of sediments along the transport pathway from Cook Inlet to the Shelikof Strait. The flux
of excess 210 Pb and organic carbon to the sediments increased
by > 2- and 4.8-fold, respectively, from Outer Cook Inlet and
the northern Shelikof Strait to the central and southern Shelikof
Strait. Based on 13 C values for surface sediments, the amount
of carbon derived from marine sources increased from 30% in
Outer Cook Inlet and the northern Shelikof Strait to 60% in
the central and southern Shelikof Strait. The good correlation
between the accumulation rate of sediment organic carbon and
excess 210 Pb fluxes (r = 0.93) suggests that scavenging of excess
210 Pb by organic carbon is an important process in this region.
Modern sediment budgets for Outer Cook Inlet and the Shelikof
Strait indicate that > 70% of the total sediment accumulation
of 61 106 tons yr-1 is deposited in the central and southern
Shelikof Strait. These sediment budgets are in good agreement
with the calculated value of 70 106 tons yr-1 of riverine and
erosional sediment transported into Outer Cook Inlet and the
Shelikof Strait. Collectively, the data support focusing of finegrained sediments and organic carbon to the central and southern
Shelikof Strait. В© 2005 Elsevier B.V. All rights reserved.
1615 Millennial-scale depositional cycles from the Holocene
of the Po Plain, Italy
Amorosi A., Centineo M.C., Colalongo M.L. and Fiorini F. Marine Geology 2005 222-223/1-4 (7-18)
The Holocene depositional history of southeastern Po Plain on
time scales of 103 yr is reconstructed, based upon integrated sedimentological and micropalaeontological analyses of nine continuously-cored boreholes, about 40 m deep. Major palaeoenvironmental changes include the rapid landward migration of a
barrier-estuary-lagoon system during the Early-Middle Holocene
(transgressive systems tract-TST), followed by extensive delta
progradation in the last 6000 yr (highstand systems tract-HST).
Detailed facies analysis of cores combined with the identification of 12 microfossils (benthic foraminifer and ostracod) associations allow an ultra-high-resolution sequence-stratigraphic
framework to be reconstructed. Particularly, eight small-scale,
high-frequency cycles, about 3-5 m thick and spanning intervals
of time of about 1000 yr, can be physically traced throughout the
study area. Interpretation of these cycles, which are invariably
bounded by sharp flooding surfaces and generally show internal
shallowing-upward trends (parasequences), indicates that relative sea-level changes during the Holocene were episodic and
punctuated by rapid phases of sea-level rise, followed by periods
of stillstand (or decreasing sea-level rise). From seaward to
landward locations, parasequence boundaries document beachbarrier migration, bay-head delta abandonment and increasing
accommodation in the coastal plain. The ensuing phases of sealevel stillstands resulted in the progressive filling of the newly
formed accommodation space, through beach progradation, extensive mud deposition in behind-barrier lagoonal (estuarine) and
305
marsh deposits, and aggradation in bay-head delta systems at the
head of estuaries. Eustacy appears to be the major controlling
factor of the retrogradational stacking pattern of parasequences
within the TST. By contrast, a complex interplay of eustacy,
sediment supply and subsidence, with an increasing influence of
autocyclic mechanisms, such as channel avulsion and delta lobe
abandonment, controlled facies architecture within the HST. The
maximum flooding surface cannot be assumed to be synchronous,
its timing being strongly dependent upon local variations in sediment influx and subsidence. This study shows that the micropalaeontologic characterization of mud-prone (coastal plain
and estuarine) successions in terms of water depth and salinity
can lead to very accurate sequence-stratigraphic interpretations,
allowing identification of parasequence boundaries that may not
be detected by conventional stratigraphic approach. В© 2005
Elsevier B.V. All rights reserved.
1616 The modern Po Delta system: Lobe switching and
asymmetric prodelta growth
Correggiari A., Cattaneo A. and Trincardi F. Marine Geology
2005 222-223/1-4 (49-74)
The modern Po Delta system, comprising five main delta lobes,
has been investigated by integrating VHR seismic surveys,
recorded offshore from water depths as shallow as 5 m to the
toe of the prodelta in about 30 m, with accurate historical cartography extending back several centuries. Previous studies give
sedimentological and geochronological information from precisely positioned sediment cores. This combined historical and
stratigraphic reconstruction of the modern Po prodelta allows
volumetric reconstructions indicating an average sediment load
of 9.4 106 t yr-1 for Po di Pila and Po di Goro-Gnocca lobes. This
estimate is remarkably consistent with the total sediment load of
11.5 106 t yr-1 available for parts of the last century from a gauge
station at the apex of the delta plain (in Pontelagoscuro). These
integrated stratigraphic studies allow to explain the key characters
of the Po delta system: a) the marked asymmetry of the whole
delta-prodelta system reflecting prevailing sediment dispersal to
the south of each individual delta outlet; b) the shore-parallel
overlapping of successive prodelta lobes fed by distinct river
outlets of ever changing relative importance; c) the delta outlets
being artificially forced in a fixed position so that natural avulsion
is prevented and delta lobes undergo headland retreat leaving a
marked erosion on the prodelta; d) the presence of prodelta lobes
showing widespread "cut-and-fill" features (ranging from 100 to
300 m and depths up to 4-5 m filled with massive silt to very fine
sand) offshore of short-lived very active distributary channels
(e.g.: Po di Tolle lobe) and suggesting that, in some particular
interval, short-lived episodes of submarine erosion are induced
by catastrophic increases in river discharge (of natural origin or
induced by human maintenance). The seismic stratigraphy of
the modern Po Delta documents that markedly distinct prodelta
architectures form when a newly activated lobe is located updrift
(north, in this case) or downdrift (south) of the one that is retreating: in the first case the abandoned lobe becomes sheltered by
the new, rapidly advancing, one; in the opposite case the retreating lobe is updrift and a substantial portion of the sediment is
cannibalized and transported to the new lobe, downdrift. В© 2005
Elsevier B.V. All rights reserved.
1617 Distributary channels and their impact on sediment
dispersal
Syvitski J.P.M., Kettner A.J., Correggiari A. and Nelson B.W.
Marine Geology 2005 222-223/1-4 (75-94)
A global analysis of world deltas, with details from a natural
and an anthropogenic-influenced delta, demonstrates how distributary channels control the flux of sediment into the coastal
ocean. The study addresses the range in the number of distributary channels across world deltas using remote sensing techniques. A power law relationship is found between the number
of distributary channels and the length of river and, separately,
the delta gradient. These relationships hold for all types of
deltas whether controlled or strongly influenced by waves, river
discharge, tides or ice (permafrost or sea-ice). Nature-controlled
deltas, such as the Klinaklini delta, have distributary channels
that act as overflow conduits that become active during flooding
events. Anthropogenic-controlled deltas, like the Po delta, have
distributary channels that are controlled for flood mitigation or
306
SEDIMENTOLOGY
low flow maintenance. Anthropogenic influences greatly impact
the natural rate of delta progradation through changes in sediment
supply, controlling the position of distributary channels, and impacting subsidence from gas and groundwater extraction. Even
with flood controls, the Po delta traps 16% of the sediment load
in its channels that are becoming super-elevated at rates of 4 to 10
cm/yr, with respect to the delta plain. A new model is formulated
and shown to predict accurately the sediment flux through each
channel, along with their hydraulic properties. Deltas with high
numbers of distributary channels produce hypopycnal plumes
with reduced transport capacity. As a result, sediment diffuses
out of the multi-channel deltas as a buoyantly driven plume,
rather than as a momentum driven jet. В© 2005 Elsevier B.V. All
rights reserved.
1618 The use of 7 Be to identify event and seasonal sedimentation near the Po River delta, Adriatic Sea
Palinkas C.M., Nittrouer C.A., Wheatcroft R.A. and Langone L.
Marine Geology 2005 222-223/1-4 (95-112)
In October 2000, a major flood event of the Po River occurred.
The resulting seabed deposit was initially sampled in December
2000, and most sites were reoccupied on subsequent cruises over
a 3-yr period. Using the maximum penetration depth of the shortlived radioisotope 7 Be (half-life 53.3 d), the flood deposit was
found to be up to 15 cm thick. Individual depocenters of thick
strata were located immediately adjacent to the distributaries at
the river mouth in relatively shallow water (< 30 m). These flood
deposit thicknesses are minimum estimates because the depth of
234 Th (half-life 24.1 d) exceeds that of 7 Be in physically stratified
flood sediment, indicating that the first sediment deposited during
the flood event likely originated from the river channel. 30-55%
of the estimated sediment load delivered to the shelf during the
flood event can be accounted for using 7 Be penetration depths.
Seasonal deposition also can be quantified using 7 Be, after removing the effects of biological mixing. Seasonal deposition
rates are a maximum of 6 cm yr-1 near the Pila distributary,
decreasing to 2 cm yr-1 in the southern portions of the dispersal
system. В© 2005 Elsevier B.V. All rights reserved.
1619 Fine-sediment mass balance in the western Adriatic
continental shelf over a century time scale
Frignani M., Langone L., Ravaioli M. et al. Marine Geology
2005 222-223/1-4 (113-133)
To obtain a quantitative estimate of the sediment accumulating on
the muddy belt extending along the western Adriatic continental
shelf, a budget was calculated based on the mass accumulation
rates measured from more than one hundred activity-depth profiles of 210 Pb. 137 Cs depth-distributions were used, when possible,
to support 210 Pb results. 210 Pb profiles show quasi-monotonic
declines in the foreset region of the central Adriatic clinoform.
In the prodelta of the rivers Po and Isonzo, 210 Pb profiles are
characterized by intervals of low and uniform activity, which
are thought to be produced by flood deposition. Since the north
Adriatic is shallow and occasionally affected by storms from
Bora wind, sediments are not in steady-state and their accumulation is the net result of recurring deposition, resuspension and
winnowing events. In the western Adriatic, mass accumulation
rates range between 0.04 and 6.6 g cm-2 yr-1 . Peak values were
recorded in the Po and Isonzo prodeltas and along a narrow belt
between Pescara and the Gargano promontory. Furthermore, the
latter depocentre is located immediately seaward of the offlap
break (40-50 m water depth) and parallels that of the most recent
sigmoid of the HST. The integration of mass accumulation rates
throughout the mud wedge of the north and central Adriatic gave
a value of 42.0 Tg yr-1 of sediment accumulating along the
Italian coast. The balance between sediment accumulation and
riverine sediment supply ( 46.6 Tg yr-1 ) suggests an export of
4.6 Tg yr-1 to the south Adriatic basin and/or the Mediterranean
Sea. The along-shore sediment transport is very effective and,
in particular, 16.2 Tg yr-1 of sedimentary material ( 35% of
the riverine supply) is transferred from north to central Adriatic,
through the Ancona section. В© 2005 Elsevier B.V. All rights
reserved.
1620 Po River plume on the Adriatic continental shelf: Dispersion and sedimentation of dissolved and suspended matter
during different river discharge rates
Boldrin A., Langone L., Miserocchi S. et al. Marine Geology
2005 222-223/1-4 (135-158)
Suspended matter and dissolved nutrients were studied in the
prodelta of the Po River (northern Adriatic Sea) immediately after one of the greatest floods of the last century, which occurred
in October 2000, and in four successive seasonal conditions.
Hydrology, total suspended matter (TSM), particulate organic
carbon (POC) and particulate nitrogen (PN) content, organic carbon stable isotopes ( 13 CPOC ), particle grain size spectra, phytoplankton, and dissolved inorganic nutrients (i.e., nitrate, nitrite,
ammonium, phosphate, and silicate) were measured in different
discharge conditions to describe processes occurring in the Po
River delta. The main effect of high river discharge was a large
volume of low salinity water at the surface that extended over the
entire study area. The concentration of most sampled variables
decreased along a dilution gradient from the Po River distributariesвЂ™ mouths to the offshore. For TSM at the surface, riverine
input and dilution were the main factors affecting its distribution.
At the bottom, however, increased TSM in the nearshore was due
to rapid sinking of suspended matter at the river mouth, while
resuspension and advection dominated the transport of near bottom sediments offshore at 15-20 m depth. In the offshore where
resuspension was active, an increase in ammonium and decrease
in oxygen supported the presence of regeneration processes occurring at the bottom. During the October 2000 flood event, high
nutrient concentrations promoted new production, triggering an
algal bloom in the southern region of the study area. The origin of
particulate organic carbon in the river delta was then estimated
from a mixing model based on 13 CPOC values and carbon :
nitrogen (C / N) molar ratios, and as the contribution of three
distinct sources of organic carbon were determined (i.e., marine,
riverine, and terrestrial). The riverine end-member accounted for
50% of the surface POC and generally decreased towards the
offshore. The terrestrial carbon contribution was generally the
least abundant (20-28% at the surface and at depth, respectively)
and exhibited peak values (30-40%) during the October 2000
flood. Last, the marine contribution was the most abundant at
the bottom ( 40%) and generally increased offshore. During the
October 2000 flood, the fluvial contribution of particulate organic
carbon, that is the terrestrial and riverine fractions, represented
approximately 80% of the total particulate organic carbon in the
Po River delta. В© 2005 Elsevier B.V. All rights reserved.
1621 Shallow gas and flood deposition on the Po Delta
Orange D., Garca- Garca A., Lorenson T. et al. Marine Geology
2005 222-223/1-4 (159-177)
Sediment cores acquired on the Po delta, northwestern Adriatic
Sea, in water depths of 10 to 25 m yielded anomalous concentrations of methane up to 41,300 ppm. Of the 19 unique sites
analyzed 5 sites (9 cores) had more than 90 ppm of CH4 and
of those, 3 sites (4 cores) had more than 13,800 ppm methane.
Compositional and isotopic analyses of the gas support a bacterial origin. Anomalous methane concentrations were found in
kasten, gravity, and box cores; where more than one core type
was acquired at a single location, all cores contained anomalous
methane. Despite the regional high productivity in the Adriatic,
all of the highest gas concentrations were found in the region associated with the thickest accumulation of recent flood deposits
off the most active channel of the Po delta (Po di Pila). Cores
acquired in this region contain primary sedimentary structures
that indicate rapid burial of thick (> 10 cm) flood deposits and a
relative lack of bioturbation down to the base of the flood layer.
We propose that in the Po delta, flood deposits deliver significant amounts of terrigenous organic matter that can be rapidly
buried on the prodelta, effectively removing this organic matter
from aerobic oxidation and biological uptake, and leading to the
potential for methanogenesis with burial. In areas unaffected by
this high flux of organic matter and rapid/thick flood deposition,
or in between flood events, our data indicate that the conditions
for methanogenesis and gas accumulation have not been met. We
suggest that in these areas, the physical and biological reworking
of the surficial sediment between flood events may effectively
oxidize and mineralize organic matter (derived from both marine
SEDIMENTOLOGY
and terrestrial sources) and limit bacterial methanogenesis in the
subsurface. В© 2005 Elsevier B.V. All rights reserved.
1622 Numerical modeling of hyperpycnal plume
Khan S.M., Imran J., Bradford S. and Syvitski J. Marine Geology
2005 222-223/1-4 (193-211)
When the density of sediment laden river water exceeds that of
the ambient ocean water, the river plunges to the ocean floor
and generates a hyperpycnal plume. Hyperpycnal plumes can
travel significant distances beyond the continental shelf and may
be sustained for hours to weeks. There are several Apennine
Rivers in Italy that are likely to develop hyperpycnal discharges
on the Western Adriatic shelf. Among them, River Tronto is
a moderately вЂ�dirtyвЂ™ river capable of producing 64 hyperpycnal
flow events (lasting 6 h) during a 100 year period. Numerical simulations of hyperpycnal events have been conducted for
the Adriatic shelf near the mouth of River Tronto using a twodimensional depth-integrated finite volume model to study the
spreading of the plume and its interaction with the alongshore
current. Simulation results indicate that the alongshore current
has great impact on the spreading and deposition pattern of the
hyperpycnal flow. Sedimentary deposits generated from a series
of simulated hyperpycnal flow events have developed undulating
bed forms. В© 2005 Elsevier B.V. All rights reserved.
1623 Pleistocene "muddy" forced-regression deposits on the
Adriatic shelf: A comparison with prodelta deposits of the
late Holocene highstand mud wedge
Ridente D. and Trincardi F. Marine Geology 2005 222-223/1-4
(213-233)
The upper Pleistocene-Holocene stratigraphy of the Adriatic margin consists of a succession of depositional sequences separated
by shelf-wide unconformities. The most recent of these depositional sequences encompasses the last ca. 25 kyr, and consists of
lowstand, transgressive and highstand units formed, respectively,
during the Last Glacial Maximum lowstand, the subsequent sea
level rise and the modern highstand. Older deposits are grouped
into four depositional sequences, each recording ca. 100 kyr
glacio-eustatic cycles during an interval between ca. 450 and
25 kyr BP. Each of these Pleistocene sequences is composed
dominantly by muddy progradational units deposited during prolonged phases of sea level fall; therefore, these sequences represent a unique example of well-preserved muddy forced-regression deposits. Detailed seismic-stratigraphic analyses show that
forced-regression deposits composing the four sequences are not
directly connected to nearshore and/or fluvio-deltaic environments. In contrast, typical forced-regression deposits defined
in outcrop and reported in the literature consist of sand-rich,
nearshore/deltaic facies preserved as patchy remnants of ancient
shorelines. We suggest that muddy forced-regression deposits on
the Adriatic shelf represent the offshore counterpart of shoreface
deposits recognised in outcrop as the product of typical forced
regressions. Interestingly, muddy forced-regression deposits on
the Adriatic shelf bear clear similarities with the late Holocene
highstand mud wedge, suggesting a common depositional mechanism through lateral advection of fine-grained sediment. In this
view, subaqueous progradation of muddy deposits occurs below
storm wave base, with a subaqueous roll-over point that, during
proceeding sea level fall, likely positioned at decreasing distance
from the time-equivalent shoreline. В© 2005 Elsevier B.V. All
rights reserved.
1624 Evolution of the RhЛ†one delta plain in the Holocene
Vella C., Fleury T.- J., Raccasi G. et al. Marine Geology 2005
222-223/1-4 (235-265)
The delta plain of the Rhone shows many sandy beach ridges
cropping out at the surface. We propose here a radiocarbon
chronology for the accumulation of the sedimentary bodies and
an interpretation of the morphology of the mouth lobes that they
form. Morphologies of the lobes depend on four principal factors: (1) the variation of the relative sea level, which constitutes
the morphogenic base level, (2) the fluvial input (volume of
water discharge and sedimentary input, number and position of
the mouths), (3) marine dynamics (volume and direction of the
longshore drift, dominant wave direction) (4) the accommodation space created by the rise of relative sea level, along with
the paleobathymetry onto which the lobe will prograde imme-
307
diately in front of the delta and at sea. Our conclusions are:
the main Holocene paleo-delta lobes of Ulmet and Saint FerrВґeol
were contemporaneous, being deposited from 4000 to 2000 yr BP.
However, the fluvial style of their downstream channel (meandering for Ulmet channel and linear for Saint-FerrВґeol) and the lobe
morphologies of both channels are contrasted: rounded in the
case of Ulmet and elongated for Saint-FerrВґeol. The role of
the accommodation space is confirmed by two recent drillholes traversing the entire Holocene succession, which reveal a
prior stage of sedimentary filling in the case of the Saint-FerrВґeol
lobe, thus limiting the accommodation space and favouring a
rapid and pointed progradation of this lobe. The decoupling
between hydrological activity and progradation of lobe indicates
the complexity of mechanisms in the large catchment basin of
RhЛ†one. However, the high rate of progradation of Saint-FerrВґeol
lobe after 2900 BP is probably a consequence of the increase
of human activity after this date. The variation of relative sea
level remains an important factor controlling the evolution of
the Rhone delta after 6000 BP. The local (?) stabilization of
the relative sea level between 4585 BP and 3520 BP played an
important role in the triggering of coastal progradation (SaintFerrВґeol lobe, eastern margin RhЛ†one delta). В© 2005 Elsevier B.V.
All rights reserved.
1625 High resolution stratigraphy and evolution of the
RhЛ†one delta plain during Postglacial time, from subsurface
drilling data bank
Boyer J., Duvail C., Le Strat P. et al. Marine Geology 2005
222-223/1-4 (267-298)
This study is based upon a large set of core drilling data (lithology and well logs) of the RhЛ†one delta plain extracted from the
French geological survey (BRGM) databank. The main goals
are to set up a sequence stratigraphy model of the postglacial
sedimentary bodies of the RhЛ†one delta plain and to evaluate the
relative importance and influence of the main controlling factors
and processes (subsidence, eustasy, sediment yield, climate, anthropic influence) that led to their formation. First, a detailed
study (60 drill holes with tenth meters spacing) was performed
on a restricted area (Saint FerrВґeol lobe, 1.5 km2 ). Correlation
between well logs data and lithological data allows to identify
the main sediment lithofacies and key surfaces, and to set up a
detailed stratigraphic framework. Postglacial deposits are subdivided into a lower member of coastal plain and backbarrier
deposits and an upper member of marine deposits (coastal barrier
environments). Following, the analysis of 160 wells distributed
on the whole delta plain depicts the large scale architecture of
postglacial deposits. In the upper delta plain, fluviatile coastal
plain and palustral deposits prevail. In the lower delta plain,
the deposits are made of a lower part of coastal plain deposits
organized into four units (T1-T4) stacked in a retrograding pattern. This lower member is truncated by an erosional surface
progressively deepening seaward. Above, an upper member
of marine deposits thickening seaward and coarsening upward
is organized into five units (P1-P5) arranged in a prograding
pattern. The core drilling data have been correlated with high
resolution seismic data on the adjacent shelf and are interpreted
in sequence stratigraphy terms. The retrogradational units (T1T4), with coastal plain deposits, are correlative of shelf units and
constitute together trangressive parasequences deposited during
phases of slowing down of postglacial sea level rise. The upper
marine units (P1-P5), arranged in a prograding pattern, represent
parasequences of the Highstand Systems Tract which have prograded since the period of reduced rate of sea level rise at the
end of the Holocene. During this period, the evolution of the
sedimentary RhЛ†one system was controlled by major changes of
the hydrologic regime. Periods of increased sediment discharge,
aggradation of the floodplain and progradation of the coastline
are correlated with the development of the deltaic lobes of the
RhЛ†one dвЂ™Ulmet (unit P3) and of the RhЛ†one du Bras de Fer (unit
P4). Unit P5 correlates with adjacent prograding shelf unit that
developed seaward of the present RhЛ†one river mouth. Comparison of sea level history between the Eastern part of the RhЛ†one
delta plain and the rocky coast to the east of Marseille suggests
that tecto-subsident movements account for part of the changes in
relative sea-level. Moreover, the truncation of transgressive and
progradation surfaces, the unevenness of the MFS, the dilatation
308
SEDIMENTOLOGY
of sedimentary record and deformations of key surfaces are also
in favor of differential subsidence.
1626 Seismic stratigraphy of the Deglacial deposits of the
RhЛ†one prodelta and of the adjacent shelf
Labaune C., Jouet G., BernВґe S. et al. Marine Geology 2005
222-223/1-4 (299-311)
In order to achieve a synthesis of the stratigraphic organization
of the Deglacial deposits of the inner/middle shelf in front of the
RhЛ†one delta plain, we merged high resolution (Mini-sparker and
Sparker), and very high resolution (chirp and mud-penetrator)
seismic data into a single seismic database. Thus, the merged
seismic database improves the lateral correlation between eastern
and western parts, separated by the RhЛ†one Incised Valley deposits. As a result the interpretation of seismic units in relation to
local and global environmental changes was refined. The Deglacial deposits rest on a basal erosional discontinuity capping
a complex of Pleistocene prograding wedges. The identified
units make up Transgressive and Highstand Systems Tracts, and
are bounded by flooding surfaces. The main flooding surfaces
are (1) the transgressive surface (D200) which forms the lower
boundary of the Deglacial deposits and (2) the maximum flooding
surface which forms the boundary between the Transgressive and
Highstand Systems Tracts. Regarding the data set the study area
is divided into three parts depending on the stacking pattern and
main control factors. In the western area the units present an
aggradational stacking pattern and the rate of sediment supply
and dynamic conditions seems coupled with glacio-eustacy role
on sedimentary units building and evolution. In the central area
the units present an overall backstepping pattern mainly controlled by glacio-eustacy. In the eastern area the units present
an aggradational stacking pattern and both the glacio-eustacy
and rate of sediment supply have an important role. The lower
parasequence of the Transgressive Systems Tract (U200) is due
to the reworking of WВЁurmian terraces. Above, the parasequence
U300 is a transgressive body formed during a rapid sea-level
rise. The two upper parasequences are interpreted as ancestral
coastal systems with a backstepping pattern. The first coastal
system (U400) is due to a decrease in the rate of sea-level rise
that occurred during the Younger Dryas. The second coastal
system (U500) may be due to a similar event or to an increased
rate of sediment supply during a constant sea-level rise. Finally
the Highstand Systems Tract is composed of three units: (i) unit
U601, located to the West and interpreted as a subaqueous delta,
(ii, iii) units U600 and U610, located to the East and interpreted
as prograding deltaic lobes.
1627 Small rivers contribution to the Quaternary evolution
of a Mediterranean littoral system: The western gulf of Lion,
France
Tesson M., Labaune C. and Gensous B. Marine Geology 2005
222-223/1-4 (313-334)
Along the Mediterranean coasts and the Atlantic French coast,
former and actual research programs focused on major river systems, estuaries and deltas, characterized by a last Glacial relative
sea level lowstand and incision and a well developed sedimentary
incised valley infilling deposited during the following sea level
rise and highstand. This paper presents the preliminary results of
a program focused on a particular area of the Gulf of Lion coast
with a thin sedimentary cover over the substratum and only minor
rivers with non-apparent and important sedimentary contribution
during the Late Quaternary. The results show that in this area
the best Pliocene to Actual sedimentary record is preserved. The
paper rests on the analysis of an extensive database of recent high
resolution and very high resolution seismic reflection lines and
previously published core data. Seismic data show that a major
complex of paleovalleys connected with the Orb, Aude and Agly
rivers is preserved on the inner shelf and adjacent coastal plain.
On the inner shelf, the separated incised valleys merged in a
unique broad and shoreparallel incision dipping southward. At
the southward extremity, the incision turns eastward and seaward.
The basal surface of this incision extends seawards under six to
seven Late Quaternary depositional sequences preserved on the
mid and outer shelf. The infilling of the complex of paleovalleys
is characterized by aggrading deposits attributed to periods of
relative sea level rise (transgressive systems tracts), organized
into several subunits bounded by internal discontinuities locally
deeply incising. The discontinuities are amalgamated surfaces,
including successive sequence boundaries (indicative of phases
of relative sea level falls) merged with transgressive surfaces
(indistinct tidal and wave ravinement surfaces). The subunits
are the part of Late Quaternary depositional sequences preserved
in estuarine environments. They are the lateral equivalents of
landward fluvial terraces and seaward coastal and prodeltaВЁД±c deposits on the shelf. Using borehole dataset, the underlying and
eroded deposits below the basal unconformity are correlated with
Pliocene deposits outcropping landward in the hinterland. The
top of the incised valleys complex is capped by the last Glacial
lowstand surface of erosion (18 ky B.P.) reworked by the postglacial transgressive surface (TS), dissociated near the shoreline
into a tidal and a wave ravinement surfaces. Above the TS, the
very high resolution (VHR) seismic data in the lagoons, the tidal
channels and cores, reveal in details the stratigraphic architecture
of the deposits. At the base, a small wedge constitutes the postglacial transgressive systems tract (TST) locally thinning in the
areas distant of the sediment point sources. The TST is capped
by a flat surface of wave reworking (maximum flooding surface
or mfs) prolongating under the Leucate lagoon and merging offshore at the seafloor. Boreholes and VHR seismic lines trough
the coastal barrier and in the lagoon show that the shoreline
probably migrated far landward at the end of the transgression.
When the rate of sea level rise decreased strongly, the shoreline
migrated seaward and prograding and aggrading sandy material,
with landward muddy lateral equivalent facies, deposited early
highstand systems tract (HST) above the MFS. Offshore, fine
material deposited as a sigmoidal blanket of mud originating in
part from the north-east and RhЛ†one river under oceanic circulation
(equivalent to a subaqueous prodelta). Subsequently, the modern
beach barrier built up by wave reworking of the early HST. This
new study of the western part of the Gulf of Lion inner shelf and
littoral illustrates an incised valley complex and thus presents the
best preserved example of the sedimentary record of the effects
of the relative sea level changes during the Pliocene to Actual
period. For the first time, the land to sea transition is preserved
and the Late Quaternary depositional sequences are in a great
part observed. The last post Glacial deposits present a simplified
but very different organisation compared to a record front of the
adjacent RhЛ†one river. Consequently a synthesis is now possible.
1628 Formation of the Aude, Orb and Herault prodeltas and
their characterisation using physicochemical and sedimentological parameters
Pauc H. Marine Geology 2005 222-223/1-4 (335-343)
The formation of Mediterranean prodeltas depends on microtidal
estuarine dynamics. The study of the Aude estuary and others
shows the usual presence of a salt wedge which induces the
formation of two turbidity maxima created by two different processes [Pauc, H. 1997. Fluvio-marine interface in a microtidal
mediterranean estuarine environment. The nepheloВЁД±d layer supply problem. Journ. Rech. OcВґeanogr. 22 (3), 83-90]. The first
process is a loss of charge due to the annulment of the current
momentum, driving sedimentation of the silt-size material. The
second process is flocculation, which results in deposition of
fine sediment. The end results of the combination of these two
processes is a sedimentary sequence with two distinct sediment
units: silt below and clay minerals above. Granulometrical and
mineralogical analysis of the sediment body enables the zone
of sedimentation of each type of material to be determined, and
hence the style of sedimentation to be inferred. Illite, quartz
and dolomite are of detrital origin and accumulate close to the
river mouths; while smectite is deposited by both dynamical and
flocculation processes, and accumulating over the surface of the
prodelta and also seaward by some 30-40 m depth. Calcite is
of biogenic origin, and is found further offshore, associated with
muddy sediments only. В© 2005 Elsevier B.V. All rights reserved.
1629 Early muddy deposits along the Gulf of Lions
shoreline: A key for a better understanding of land-to-sea
transfer of sediments and associated pollutant fluxes
Roussiez V., Aloisi J.- C., Monaco A. and Ludwig W. Marine
Geology 2005 222-223/1-4 (345-358)
Large quantities of sediment introduced by rivers especially during flood events lead to the formation of prodeltaic structures
characterized by fine-grained deposits in the proximal area of the
SEDIMENTOLOGY
shelf. According to their mean grain size, it is largely admitted
in the literature that these deposits mainly stand below the storm
wave base. In the Gulf of Lions (NW Mediterranean), however,
our data show that these muddy sediments also exist above the
storm wave limit, in the uppermost unit of the Holocene prism.
The purpose of this work is therefore to draw a detailed sedimentological and geochemical portrait of these units, and to discuss
the processes involved in the sedimentation and remobilization
of these sediments. Our results show that the fine particles accumulate earlier in the inner-shelf in front of the nearby rivers,
in association with the chemical elements which are commonly
associated with this grain size fraction (e.g. organic carbon,
radionuclides, and heavy metals). This accumulation probably
mainly occurs during storm and flood events. The early deposits
are then exposed to resuspension events and can actively participate to the distribution of fine-grained sediment in the entire
margin by advective transfers via the benthic nepheloid layer.
These fine-grained nearshore prodeltas are a common feature of
the Mediterranean deltaic systems and mark the frontal processes
that occur at the continent/sea interface of non-tidal seas. Our
results especially point out the potential use of heavy metals as
markers of the tracking of riverine sediments, which is naturally
an important condition when evaluating the ultimate fate of landderived pollutants in the marine realm. But also more fundamental studies on the understanding of sedimentological processes
and reconstruction of margin stratigraphies should consider these
deposits as functional units for the distribution of platform sediments. В© 2005 Elsevier B.V. All rights reserved.
1630 Development of the Kura delta, Azerbaijan; a record
of Holocene Caspian sea-level changes
Hoogendoorn R.M., Boels J.F., Kroonenberg S.B. et al. Marine
Geology 2005 222-223/1-4 (359-380)
Late Holocene deposits of the Kura delta indicate an alternating
dominance of deltaic and shallow marine environments. These
major environment shifts are controlled by the high frequency
sea-level changes of the Caspian Sea. The level of the Caspian
Sea, now at 27 m below Global Sea Level (GSL), changes at
rates of up to a hundred times as fast as global sea level, allowing
observation of sedimentary processes on a decadal scale that
would take millennia in an oceanic environment. The modern
Kura delta is a river-dominated delta with some wave action
along its north-eastern flank, and without tidal influence. Morphological and hydrological changes have been monitored for
over 150 years, continuing up to the present day using remote
sensing imagery. Offshore sparker survey data, onshore and offshore corings, biostratigraphical analysis and radiometric dating
enable a reconstruction of the Holocene Kura delta. Four phases
of delta progradation alternating with erosional transgressive surfaces have been identified, representing just as many cycles of
sea-level fall and rise. The first cycle is represented by lowstand
deposits truncated by a transgressive surface (TS1) at ca. 80 m
below GSL. TS1 is overlain by several metres of laminated clays
and silts, deposited during a Late Holocene forced regression
(H1). These deposits are truncated by the prominent reflector
(TS2), corresponding to the Derbent lowstand around 1500 yr
BP and subsequent transgression. This transgressive surface is
overlain by prograding shallowing upwards deposits, H2, in turn
truncated by a third transgressive surface (TS3), correlated with a
lowstand of ca. 32 m below GSL. The last phase, H3, comprises
an onshore progradational unit followed by an aggradational unit
with an offshore veneer of clays and silts, corresponding to the
formation of the modern Kura delta that started at the beginning
of the 19th century. В© 2005 Elsevier B.V. All rights reserved.
1631 Internal structure and evolution of the Late Quaternary sequence in a shallow embayment: The Amvrakikos
Gulf, NW Greece
Kapsimalis V., Pavlakis P., Poulos S.E. et al. Marine Geology
2005 222-223/1-4 (399-418)
The Late Quaternary stratigraphic pattern of the Amvrakikos
Gulf in the eastern Mediterranean has been studied on the basis of the analysis of high-resolution seismic profiles and short
sediment cores. Lowstand, transgressive and highstand systems
tracts have been identified that are configured in a major depositional sequence of a fifth-order sea level cycle. During the last
glaciation, when the sea level was lowered by 55 m relative
309
to its present position (ca. 50 ka BP), the Amvrakikos Gulf
was probably emerged, giving rise to: (a) subaerial erosion and
fluvial incision in the western shallow part of the Gulf; and (b)
development of a paleo-lake in the eastern deepest domain. Until
the early phase of the post-glacial transgression (ca. 11-50 ka
BP), a paleo-river, characterized by a dense network of V-shaped
valleys, was draining the western part of the Gulf and flowing into
the Ionian Sea. In the isolated eastern part, lowstand lacustrine
deposits (deltaic and prodeltaic units) accumulated within the paleo-lake. At the latter stage of the last post-glacial transgression
(ca. 11 ka BP), seawater entered the Gulf and the transgressive
systems tract was deposited, consisting of incised-channel fills,
beach-shoreface deposits and delta/prodelta wedges. Buried terraces have been identified also within this transgressive tract that
reveal a step-like sea level rise. Since ca. 6 ka BP, when the
sea level reached its present-day position, a distal prodeltaic unit
has been deposited and overlain by prograding deltaic wedges.
The spatial distribution of these wedges provides evidence of a
continuous shifting of the river mouths during Holocene. The
recent sedimentation patterns are related to the terrigenous inputs
primarily from the Arachthos River, located in the northeastern
part of the Gulf, and secondarily from the Louros River, located in
the northwestern part. В© 2005 Elsevier B.V. All rights reserved.
1632 Stratigraphic signature of the Vesuvius 79 AD event
off the Sarno prodelta system, Naples Bay
Sacchi M., Insinga D., Milia A. et al. Marine Geology 2005
222-223/1-4 (443-469)
Sedimentological and chemical analysis of gravity core samples,
along with the interpretation of very high resolution, single channel seismic reflection profiles acquired off the Sarno prodelta
system (southeastern Naples Bay), document the sedimentary
facies and seismic stratigraphic signature of the tephra deposit
erupted by Vesuvius during the plinian eruption of 79 AD. The
79 AD pyroclastic deposits sampled off the Sarno prodelta system revealed significantly different characters with respect to
both the subaerial succession documented from the type sections of Pompeii, Herculaneum and Oplontis and the more distal
pyroclastic fallout deposits that were recovered from the outer
continental shelf off the northern Salerno Bay. This was likely
to be expected as, in proximal subaqueous settings, both primary
deposition and reworking of tephra are known to be influenced
by the hydrodynamics of the water itself (induced by the pyroclastic currents entering the sea) as well as by the early instability
of pyroclastic bedforms due to the exceptionally high sediment
yield during volcanic eruption. According to the data illustrated
and discussed in this study, we suggest that the 79 AD tephra
deposit sampled off the Sarno prodelta is likely to be the result of
a number of syn-eruptive genetically-related depositional and/or
erosional mechanisms associated with (1) anomalous waves (tsunami) and currents generated by the entrance of pyroclastic flows
and surges into the sea; (2) subaqueous density flows evolved
from the impact of hot pyroclastic currents into the seawater;
(3) failure of water-logged, cohesionless pumice deposits, due to
instability of pyroclastic bedforms rapidly accumulating on the
seafloor. Seismic interpretation revealed that the Upper Holocene
sequence off the Sarno prodelta system is affected by extensive
creep involving the whole post-79 AD succession. Deformation
due to creep is documented by slumping of semi-consolidated
strata over a basal surface represented by the lithologic discontinuity between the base of the 79 AD tephra deposits and the
underlying hemipelagite. Seismic data also suggest that gravitational instability of this area has been induced, or enhanced,
by significant volcanotectonic deformation and local uplift of the
seafloor that ostensibly predated the eruptive event. The results
of this research may be relevant to studies of other eruption
events in close proximity to coastlines in terms of wave- and/or
current-generated sedimentary features as a possible explanation
of unusual subaqueous facies architecture. В© 2005 Elsevier B.V.
All rights reserved.
1633 Mediterranean river systems of Andalusia, southern
Spain, and associated deltas: A source to sink approach
Liquete C., Arnau P., Canals M. and Colas S. Marine Geology
2005 222-223/1-4 (471-495)
The northern shores of the semi-isolated Mediterranean Sea with
310
SEDIMENTOLOGY
its low tidal range and a relatively voluminous fluvial supply
of sediments constitute an ideal delta forming environment. In
this paper, we examine the present-day and multi-decadal behaviour of 26 river systems from Andalusia, southern Spain,
forming deltas in the Alboran Sea, the westernmost basin in the
Mediterranean Sea. Eastern, Central and Western Andalusian
watersheds have been defined based on geomorphological, climatological and hydrological characteristics. A comprehensive
data set has been compiled, including satellite images, aerial photographs, a digital elevation model, thematic maps, time series of
precipitation, temperature and water discharge, and the damming
history of individual river basins. This data set has been used
to analyse basin morphology and hydrology, and anthropogenic
impact. Several modelling approaches have been applied to
obtain the water budget and mean annual sediment yield of 12
of the 26 studied river systems. In addition, the periodicities
of water discharge events and their possible link with North
Atlantic Oscillation (NAO) fluctuations have been also studied.
A decreasing trend has been observed in most water discharge
time series during the last decades, which has been attributed
to natural factors. Although it could have been expected that
the diminution of water discharge may have caused a reduction
in sediment load, calculated sediment discharge time series do
not show any significant tendency. In general, sediment yield
shows an opposite relationship with basin area. A comparative
analysis of Spanish Mediterranean deltas indicates that in terms
of sediment transport Andalusian river systems are quite efficient
despite the small size of their catchments. Repetitive flood events
and the consequent suspension plumes off river mouths play a
major role in the development of deltaic and prodeltaic bodies.
Nowadays, 42% of the study area is regulated, although to date
the effect of dam building is hardly noticeable on river mouths.
В© 2005 Elsevier B.V. All rights reserved.
1634 Characterization of deltaic sediment bodies based on
in situ CPT/CPTU profiles: A case study on the Llobregat
delta plain, Barcelona, Spain
Lafuerza S., Canals M., Casamor J.L. and Devincenzi J.M. Marine Geology 2005 222-223/1-4 (497-510)
This article describes a preliminary study on the Llobregat delta,
Spain, which includes the construction of a 3D model from cone
penetration tests (CPT) and piezocone tests (CPTU) in order to
establish the architectural stacking pattern of deltaic sediment
bodies. The sediment facies identified from boreholes have been
characterized by using their mechanical behaviour and have been
used to identify the depositional sequence of the Llobregat delta.
Within the general architectural frame, flood plain silts and silty
sands, crevasse sands, fluvial channel sands, sand ridges, delta
front silts and clays, and prodelta silts and clays have been characterized as a function of cone tip resistance (qc ) and sleeve friction
(fs ). From the sediment facies characterization, a depositional
sequence constituted by three systems tracts is proposed. The
sequence is divided into: a lowstand systems tract (LST) represented by fluvial gravels, a transgressive systems tract (TST)
constituted by a fining-upward sequence with a thin sand sheet
below silts and clays, and the highstand systems tract (HST)
represented by three prograding wedges displaying coarseningupward sequences. We emphasize the simplicity, speed, high
spatial resolution and low cost of CPT/CPTU grids as a new
tool enabling us to reconstruct the three-dimensional structure
of deltaic environments for sedimentological and stratigraphical
purposes. В© 2005 Elsevier B.V. All rights reserved.
1635 Origin of depositional sequences from TВґemara caves
(Morocco) based on heavy minerals and quartz grains exoscopy (French) (Origine du remplissage sВґedimentaire des grottes de TВґemara (Maroc) dвЂ™après lвЂ™Вґetude des minВґeraux lourds et
lвЂ™Вґetude exoscopique des grains de quartz)
Niftah S., Debenath A. and Miskovsky J.- C. Quaternaire 2005
16/2 (73-83)
Quaternary deposits of the areas of Rabat and Casablanca
(Morocco) have been intensively investigated. We focus here
on depositional sequences from the caves of El Mnasra (Casino),
Ouled Bouchikha (Les Contrebandiers) and El Harhoura II in the
area of TВґemara. The sequences are correlated with isotopic stages
3 and 2. Exoscopic study under ESEM (Environmental Scan-
ning Electron Microscope) of quartz grains selected throughout
the different sequences has helped to describe sediment transport processes, Sediments originating from various areas of the
Moroccan Meseta and Middle Atlas, were carried by wind and
river transport, and then deposited along the coastal continental
shelf They followed there a complex evolutionary process before
completing their transport which ended in the TВґemara caves.
1636 Sedimentological study of sediment from an hypersaline system of oriental Tunisia in recent quaternary: MokВґ
nine sebkha (French) (Etude
du remplissage sВґedimentaire dвЂ™un
système hypersalin de la Tunisie orientale au cours du quaternaire rВґecent: La sebkha de Moknine)
Chairi R. Quaternaire 2005 16/2 (107-117)
Results from a detailed sedimentological study of sediments from
Moknine sebkha indicate two different deposit episodes. The
first is characterized by an abundance of mud and organic matter
which is good preserved in clay level. The second episode is
qualified by the progradation of clay and organic matter to the
centre. This evolution is controlled by two important factors such
as dissymetry of basin topography and the abundance of rivers
on the West. In the past, the sebkha is widened than actual. The
abundance of clay in the base of the sequence at the periphery
and in intermediate zone gives evidence. Clay level is rich on
smectite which is more deposit in the center of the sebkha and
contains high quantity of organic matter. Organic matter fraction
is dominated by autochthonous material indicated by high values
of hydrogen index and n-alkanes centred on nC18 and nC22.
1637 Sedimentation model for the quaternary intramontane
Bhimtal-Naukuchiatal Lake deposits, Nainital, India
Shukla U.K. and Bora D.S. Journal of Asian Earth Sciences 2005
25/6 (837-848)
The Bhimtal-Naukuchiatal Lake was created due to blocking of
the valley by a huge debris flow along a narrow outlet at about 40
ka BP. The lake basin was filled intermittently due to fluvio-lacustrine and colluvial processes that deposited a thick sequence of
interbedded mud and gravel. In the basin fill sequence five major
lithofacies, most of them divisible into subfacies, have been identified and assigned to specific depositional environments. The
coarsening upward (CU) mud-silt cycles represent sedimentation
in a lake setting. The clasts-and mud-supported gravels consists
of fining upward (FU) and CU sequences, respectively, indicating deposition by channel processes and debris flows. Having
basin wide extent, the pedogenic mottled, clayey silt unit represents an important tectonic event when the lake was temporarily
drained and sediments were sub-aerially exposed. Fluctuating
arid-semiarid to humid climatic conditions and repeated tectonic
activity may have governed the mode of sedimentation and ultimately the basin fill history. В© 2004 Elsevier Ltd. All rights
reserved.
1638 History of sedimentary infilling and faulting in Subic
Bay, Philippines revealed in high-resolution seismic reflection
profiles
Cabato Ma.E.J.A., Rodolfo K.S. and Siringan F.P. Journal of
Asian Earth Sciences 2005 25/6 (849-858)
Subic Bay sediments and faults identified in seismic-reflection
profiles were dated using sea-level curves. The oldest sedimentary packages are marine sediments subaerially exposed and
eroded 20 ka. Fluvio-marine to wholly marine sediments were
deposited during the ensuing transgression, and prograding units
were deposited during stillstands or minor sea-level falls. Faults
within the bay have three age ranges. The oldest set cuts through
the pre- 18 O Stage 2 rock units, >18 ka; a second disrupts 10.211.3 ka sediments; and the youngest, which cut the uppermost
sedimentary package, show that movements occurred about every
2 ky, most recently about 3 ka. Northwest-southeast faults that
parallel onshore structures associated with Paleogene emplacement of the Zambales Ophiolite Complex to the west and north
likely represent rejuvenated tectonism. The northern coastline
and north-south-trending axial bay islands appear related to a
lineament that dissects Mt Pinatubo farther northeast. A breach
in the caldera of Mt Natib is the most likely source of a presumed pyroclastic deposit in the eastern bay that is associated
with sediments about 11.3-18 ka, indicating that a Natib eruption
SEDIMENTOLOGY
occurred much more recently than previously documented for
this volcano. В© 2004 Elsevier Ltd. All rights reserved.
1639 Bar and dune development during a freshet: Fraser
River Estuary, British Columbia, Canada
Villard P.V. and Church M. Sedimentology 2005 52/4 (737-756)
Bi-weekly multi-track sonar surveys collected along a 2-km reach
of the estuarine South Arm of the Fraser River, British Columbia,
Canada, during seasonal high flows document the initiation, development and interaction of dune and bar morphologies. Bedforms of several scales developed in well-delineated fields. Bedforms that appear to fit accepted equilibrium depth-scaling developed in the main channel during rising discharge when there
was little local aggradation. During the rising stage, a bar also
formed along the tidal shelf of the channel, migrated downstream
and expanded into the main channel. Dunes that formed along
the bar crest, a region of rapid deposition, lagged flow conditions
and were larger than expected based on depth-scaling relations.
The larger dunes developed simultaneously, although bar growth
lagged dune development and was initially partially obscured by
the more rapidly developing dune field. It appears that rapid
deposition enhances dune development along the channel tidal
shelf to dimensions larger than would be expected by simple
depth-scaling rules. Smaller dunes that fit equilibrium depthscaling relations re-established themselves throughout the study
area during falling discharge when there was again little or no
aggradation. Bed-material transport rates estimated from the
migration rates of the large dunes suggest that, at high flows, the
dunes transport the majority of the material found within the bar.
В© 2005 International Association of Sedimentologists.
1640 Quantification of the dry aeolian deposition of dust on
horizontal surfaces: An experimental comparison of theory
and measurements
Goossens D. Sedimentology 2005 52/4 (859-873)
Eight techniques to quantify the deposition of aeolian dust on horizontal surfaces were tested in a wind tunnel. The tests included
three theoretical techniques and five measurement techniques.
The theoretical techniques investigated were: the gradient technique, the inferential technique without grain-shape correction,
and the inferential technique corrected for grain shape. The
measuring techniques included the following surrogate surfaces:
a water surface, a glass surface, a metal surface, a vertical array
of metal plates, and an inverted frisbee filled with glass marbles.
The efficiency of the techniques was investigated for the sediment
as a whole (all grain sizes together) as well as for a large number
of grain sizes extending from 1 to 104 m. The surrogate surfaces
showed more or less comparable catch efficiencies, although the
water surface nearly always caught the highest quantities of dust
and the marble-filled frisbee and the vertical array of metal plates
the lowest quantities of dust. The dust fluxes calculated by theoretical methods were markedly different from those obtained
by direct measurements. The fluxes calculated by the inferential
technique approximated those of the direct measurements only
for grain sizes between 30 and 40 m. For smaller and coarser
grains, deviations from the measured fluxes were high. The
gradient method, in its turn, provided extremely low calculated
fluxes for grains in all size classes investigated. The latter technique was not considered very reliable for the dust used in the
tests. В© 2005 International Association of Sedimentologists.
1641 Effects of calculation procedure and sampling site on
trap method estimates of sediment resuspension in a shallow
lake
Horppila J. and Nurminen L. Sedimentology 2005 52/4 (903-913)
Resuspension estimates given by two different trap methods in a
shallow lake were compared. The sensitivity of the methods to
errors in estimates of gross sedimentation and organic fraction of
trapped material was explored. The methods were label method,
in which resuspension is estimated by determining the organic
fraction of surface sediment, suspended seston and trapped material, and SPIM/SPM method, where the relationship between
settling particulate inorganic matter (SPIM) and total settling
particulate matter (SPM) is used. During the whole 111 day
study period, according to the label method, at a sheltered station
1949 g m-2 dry weight of sediment was resuspended, whereas
SPIM/SPM gave an estimate of 1815 g m-2 . The difference in
311
the estimates was probably due to mineralization loss of organic
material in the traps during the two week exposure periods. Sensitivity analysis showed that of the two methods, the label method
was more sensitive to variations in the organic content of trapped
material. At a wind-exposed station, the total amounts of resuspended matter given by the label method and by the SPIM/SPM
method were 4966 g m-2 and 4971 g m-2 , respectively. Due to
wind effects, escape of trapped material took place, which caused
underestimation of gross sedimentation and compensated the effects of mineralization loss to diminish the difference between
the methods. Of the two methods, the SPIM/SPM method seems
thus more suitable for lakes, where bacterial activity is high. If
cyanobacterial blooms take place, the label method is probably
more reliable, providing that the exposure time of sediment traps
is kept adequately short. В© 2005 International Association of
Sedimentologists.
1642 Recent evolution of a Mediterranean deltaic coastal
zone: Human impacts on the Inner Thermaikos Gulf, New
Aegean Sea
Kapsimalis V., Poulos S.E., Karageorgis A.P. et al. Journal of
the Geological Society 2005 162/6 (897-908)
The Inner Thermaikos Gulf is located in the northwestern Aegean
Sea, receiving water and sediment fluxes from the Axios, Aliakmon, Gallikos and Loudias Rivers. The geomorphological and
sedimentological evolution of the system is reconstructed for the
last 150 years (1850-2000), on the basis of detailed analysis of
historical bathymetric charts. Late Holocene history is considered within the context of changing riverine sediment supply and
human activities. Three evolutionary stages are identified. Stage
I (1850-1916) corresponds to a natural phase of rapid deltaic
progradation and sea-floor deposition, with an average sediment
accumulation rate of 6.5 106 m3 a-1 . During Stage II (19461956), human interference (e.g. artificial changes in river delta
plains, realignment of channels and land reclamation schemes) to
the deltaic system increased sediment delivery to the coastal waters by a factor of three; this, in turn, enhanced the progradation of
the active river mouth areas. In contrast, Stage III (1956-2000) is
characterized by significant coastline (deltaic) retreat and erosion
of the adjacent sea floor (net loss of 2.5 106 m3 a-1 ); this was
as a result of extensive river damming, which trapped a significant part of the sediment moving seaward. Furthermore, these
human impacts have affected the character of the surficial seabed sediments of the Gulf, by reducing the proportion of mud.
The response of the deltaic margin of the Inner Thermaikos Gulf
to various anthropogenic interventions seems to be analogous
to that of other deltas in the Mediterranean region where large
drainage projects, the development of irrigation networks and
dam construction have taken place within their river basins.
1643 Sudden enhancement of sedimentation flux of210 Pbex
as an indicator of lake productivity as exemplified by Lake
Chenghai
Wan G., Chen J., Xu S. et al. Science in China, Series D: Earth
Sciences 2005 48/4 (484-495)
The fundamental assumption of 210 Pb sediment dating is the stable flux of 210 Pbex , which was derived from atmosphere and then
transferred into sediments via lake water. When the sedimentation rate is relatively constant, the 210 Pbex activity in sediments
will be exponentially reduced with sedimentation age. 210 Pb
ex in lake water is incorporated into sediments mainly via organic particulates. If the sedimentation flux of organic matter
in lake water is suddenly increased, 210 Pbex will be significantly
deposited and then transferred into sediments. On the one hand
such sudden purification effect is obviously unfit for the fundamental assumption of 210 Pb dating; on the other hand, the
sudden enhancement of 210 Pbex flux would be indicative of the
conspicuous variation of primary productivity of lake water. This
problem will be discussed in accordance with the variation trend
of 210 Pbex in the vertical profile of recent sediments of Lake
Chenghai, Yunnan Province. The sediment core was collected
from the deep-water area of Lake Chenghai in June 1997. The
vertical profile of 137 Cs activity is characterized by a tree-peak
pattern. This profile gave reliable ages, and also showed the
stability of sediment accumulation in the recent ten years. The
vertical profile of 210 Pbex activity displays a specific distribution
312
SEDIMENTOLOGY
of peaks, and is similar to the vertical profile of Corg . This phenomenon seems to be related to the mechanism of constraining
the transfer of 210 Pbex into lake sediments. The average atomic
ratios of Horg /Corg and Corg /Norg in Lake Chenghai sediments are
5.51 and 7.04, respectively, indicating that the organic matter was
predominantly derived from the remains of endogenic algae. In
terms of the three-stage evolutionary characteristics of organic
matter in sediments, i.e., "deposition-decomposition-accumulation", the sedimentation fluxes (F(Corg)) of organic carbon (Corg )
since 1970 were calculated by modeling. The sedimentation
fluxes of 210 Pb ex (F(210 Pbex )) in different years display good
synchronous relations with the sedimentation flux of organic
carbon (F(C org )), especially in the years of 1972-1974 and 19861989. The variation of F(Corg ) led to the variation of F(210 Pb ex );
the variation of F(210 Pbex ) reflects, to some extent, the historical
variation of lake productivity. Copyright by Science in China
Press 2005.
1644 Hydraulic behavior of tsunami backflows: Insights
from their modern and ancient deposits
Le Roux J.P. and Vargas G. Environmental Geology 2005 49/1
(65-75)
Tsunamis are unpredictable, catastrophic events, and so present
enormous difficulties for direct studies in the field or laboratory.
However, their sedimentary deposits yield evidence of a wide
variety of hydrodynamic conditions caused by flow transformations on a spatial and temporal scale. Tsunami deposits ranging
from the Miocene to modern times identified at different localities along the Chilean coast are described to provide a database
of their characteristics. Among the typical features associated
with tsunami deposits are well-rounded megaclasts eroded from
coastal alluvial fans or beaches by very dense, competent flows.
Sand injections from the base of these flows into the substrate indicate very high dynamic pressures, whereas basal shear carpets
suggest hyperconcentrated, highly sheared flows. Turbulence
develops in front of advancing debris flows, as indicated by megaflutes at the base of scoured channels. В© Springer-Verlag 2005.
Sediments and sedimentary
processes - diagenesis
1645 Facies-related diagenetic alteration in lacustrinedeltaic red beds of the Paleogene Ergeliin Zoo Formation
(Erdene Sum area, S. Gobi, Mongolia)
Dill H.G., Khishigsuren S., Melcher F. et al. Sedimentary Geology 2005 181/1-2 (1-24)
The Late Eocene Ergeliin Zoo Formation, Mongolia, was subdivided into four facies associations/stratigraphic units which are
characterized by various carbonate minerals: (I) mud-sand flat
(low-Fe dolomite, high-Mg calcite), (II) delta front (high-Mn
dolomite, low-Mg calcite), (III) delta plain (high-Mn calcite,
low-Mg and moderate-Fe calcite), (IV) calcretes (high-Mg calcite). Besides carbonate minerals, prevailing among the cement
minerals, some sheet silicates (Ca smectite, palygorskite, illite),
apatite and Fe oxide-hydroxides occur in the siliciclastics of these
lacustrine-deltaic red beds. The prodelta/mud-sand flat deposits
(unit I) were dolomitized and cemented by high-Mg calcite during evaporative pumping at times of low lake-stand under redox
conditions greater than 0 and intrastratal solutions of strong alkalinity. Manganoan dolomite is fairly widespread in the delta front
sediments (unit II), the Mn content of which is likely to have been
derived from decomposition of vertebrate remains. The Mn/Fe
ratio in the carbonate minerals was controlled by the redox conditions and the shallow burial depth. In the porous delta front
sediments Eh values around zero and pH values slightly above
7 occurred as a result of basinward fluid movements (high-Mn
dolomite, high-Fe dolomite, low-Mg calcite). Fluid movement
was locally impeded by finer-grained delta plain deposits (unit
III), intertonguing with arenaceous aquifers (low Mg-moderate
Fe calcite, high-Mn calcite). Higher up on the delta plain with
deposits laid down in an environment transitional between distal
alluvial and deltaic (unit IV), closed lake basin conditions reappeared as fluids emerged from the distal alluvial-fluvial deposits
or were driven by capillary force to ascend and form calcretes
abundant in Mg-bearing calcite. The climatic conditions in the
Erdene Sum area, Mongolia, are likely to have been semi-arid
transitional into arid. В© 2005 Elsevier B.V. All rights reserved.
1646 Early diagenesis impact on precise U-series dating of
deep-sea corals: Example of a 100-200-year old Lophelia
pertusa sample from the northeast Atlantic
Pons- Branchu E., Hillaire- Marcel C., Deschamps P. et al.
Geochimica et Cosmochimica Acta 2005 69/20 (4865-4879)
Deep-sea coral has proved useful for paleoceanographic reconstructions and for documenting 14 C-ages of water masses using
230 Th-ages. However, for precise and accurate U-series dating,
further information on coral-age structure, growth rate and diagenetic evolution is still needed. To document such processes, we
used U-Th-226 Ra systematics in a 40 cm diameter, Lophelia pertusa specimen collected in 1912 from the Eastern Atlantic (Sea of
the Hebrides). External parts of the specimen are thought to have
been alive when collected whereas more internal parts were likely
dead. The "live-collected" and "dead" parts of the skeleton were
sampled and analyzed for their 230 Th, 232 Th, 234 U, 238 U, 226 Ra and
Ba contents by thermal ionization and multicollector inductively
coupled plasma mass spectrometry. 230 Th/234 U ratios in the most
recent parts yielded ages of 86 6 a and 92 9 a, in agreement
with the date of recovery. The older parts yielded 230 Th ages ranging from 169 15 to 211 10 a (n = 5), but had a 31% higher
U content than more recent parts of the skeleton. This raises
concerns about the possibility of secondary diagenetic U uptake,
although an environmentally controlled U/Ca shift between coral
growth stages cannot be ruled out. 226 Ra/Ba measurements were
made, and model- 226 Ra/Ba ages averaging 250 12 yr were
calculated for the older part, assuming a constant initial 226 Ra/Ba
ratio in bottom waters. These ages are slightly older than 230 Thages, suggesting either that 226 Ra/Ba ratios of ambient-seawater
changed over time or that a diagenetic phenomenon have affected
the U-series system, or both. Scanning electron microscope observations revealed bioerosion and secondary biomineralization
in the older part of the coral skeleton, supporting the hypothesis
that diagenetic processes may have influenced the ages obtained
by the U-series toolbox. Modeled U-series ages for such an open
system are discussed. However, a comparison between 14 C- and
230 Th-ages performed on both pristine and bioeroded parts of
the coral gives coherent values (ca 450 a) for the preindustrial
14 C-reservoir age of North Atlantic waters. It remains to be
determined, however, whether diagenesis occurs rapidly over a
short period of time, or whether it continues for longer periods.
In the latter case, diagenetic processes would hamper paleoceanographic interpretations as well as the precise calculation of 14 C
ages of deep-water masses, based on comparative U/Th- and
14 C-chronologies. Copyright В© 2005 Elsevier Ltd.
1647 Vertical variations in bassanite distribution patterns
in near-surface sediments, southern Egypt
Mees F. and De Dapper M. Sedimentary Geology 2005 181/3-4
(225-229)
Nile valley sediments of the El AdaВЁД±ma area in southern Egypt
contain bassanite (CaSO4 0.5H2 O), associated with gypsum
(CaSO4 2H2 O), in the upper 1 m of the deposits. The presence
of bassanite at this site, formed by dehydration of gypsum, is
marked by variations in mode of occurrence with depth. In the
lowest bassanite-bearing interval, bassanite occurs mainly along
the contact between gypsum crystals in pores, which is related
to the protection of bassanite from rehydration in those parts of
the gypsum aggregates. At a higher level, bassanite occurs along
the sides of lenticular gypsum crystals in the sediment matrix.
Near the top of the studied sequence, bassanite mainly appears
as inclusions in gypsum crystals, which represents a texture that
developed by repeated dehydration and rehydration. Elsewhere
in the upper part of the deposits, bassanite occurs as aggregates of
small crystals in pores, without associated gypsum, which was
entirely dehydrated to bassanite in these parts. These vertical
variations in bassanite distribution patterns record differences in
the diagenetic history of the deposits between depth intervals. В©
2005 Elsevier B.V. All rights reserved.
SEDIMENTOLOGY
Sedimentary geochemistry
1648 Recent variations in sediment organic carbon content
in Lake Soyang (Korea)
Khim B.- K., Jung H.M. and Cheong D. Limnology 2005 6/1
(61-66)
Four gravity cores were taken from Lake Soyang, which was
created by the construction of an artificial dam in 1973. The variation of organic carbon content of the bottom sediments since the
construction was interpreted using a variety of sedimentological
and geochemical measurements. Based on the textural properties of sediments and the total organic carbon (TOC) content, it is
clear that sediment organic carbon has been deposited very consistently throughout the postconstruction period, except for local
sudden inputs caused by summer flooding events near fish farms
or farmland areas. The autochthonous input resulting from the
enhanced primary production led by phytoplanktons each year
is likely to become a major problem at downstream sites within
Lake Soyang. The vertical variation of 13 C values of sediment
organic matter also reflects the fact that the level of autochthonous supply of organic carbon becomes high downstream. В©
The Japanese Society of Limnology 2005.
1649 Dynamics of redox changes of iron caused by lightdark variations in littoral sediment of a freshwater lake
Gerhardt S., Brune A. and Schink B. Biogeochemistry 2005 74/3
(323-339)
Depth profiles of oxygen concentration and the redox status of
acid-extractable iron were measured in littoral sediment cores of
Lake Constance incubated under a light-dark regimen of 12 h.
While oxygen penetrated to 3.4 0.2 mm depth in the dark, photosynthetic oxygen production shifted the oxic-anoxic interface
down to 4.0 0.2 mm or 5.9 1.6 mm depth, at low or high light
intensity, respectively, and caused a net oxygen efflux into the
water column. After a light-dark or dark-light transition, the oxygen concentration at the sediment surface reached a new steady
state within about 20 min. The redox state of the bioavailable
iron was determined in 1-mm slices of sediment subcores. After
a dark period of 12 h, 85% of the acid-extractable iron (10.5
mol cm-3 total) in the uppermost 8 mm was in the reduced state.
Within 12 h at low or high light intensity, the proportion of ferrous
iron decreased to 82 or 75%, respectively, corresponding to net
rates of iron oxidation in the range of 244 and 732 nmol cm-3
h-1 , respectively. About 55 or 82% of the iron oxidation at low
or high light intensity occurred in the respective oxic zone of the
sediment; the remaining part was oxidized in the anoxic zone,
probably coupled to nitrate reduction. The areal rates of iron
oxidation in the respective oxic layer (21 or 123 nmol cm-2 h-1
at low or high light intensity, respectively) would account for 4
and 23% of the total electron flow to oxygen, respectively. Light
changes caused a rapid migration of the oxic-anoxic interface in
the sediment, followed by a slow redox reaction of biologically
available iron, thus providing temporal niches for aerobic iron
oxidizers and anaerobic iron reducers. В© Springer 2005.
1650 Redox changes of iron caused by erosion, resuspension
and sedimentation in littoral sediment of a freshwater lake
Gerhardt S. and Schink B. Biogeochemistry 2005 74/3 (341-356)
Depth profiles of oxygen concentration and the redox status of
acid-extractable iron were measured in littoral sediment cores
of Lake Constance after mechanical removal of surface sediment, mixing, and re-deposition. In undisturbed sediment cores,
oxygen penetrated down to 2.9 0.4 mm or 4.6 0.4 mm depth,
respectively, after 12 h of incubation in the dark or light; causing
a net diffusive flux of 108 20 nmol cm-2 h -1 oxygen into or
152 35 nmol cm-2 h-1 out of the sediment. The uppermost 20
mm layer of the undisturbed sediment cores contained 10.2 0.7
mol cm-3 ferrous and 3.8 1.1 mol cm-3 ferric iron. After
erosion, the oxic-anoxic interface in the newly exposed sediment
was shifted to about 2 mm depth within 30 min, causing an oxygen flow into the sediment. During the following 12 h, oxygen
penetrated deeper into the sediment, and in the light oxygen was
produced photosynthetically. Ferrous iron was largely oxidized
within two days after erosion. The oxidation rates were higher
in oxic than in anoxic sediment layers, and decreased with time.
313
This oxidation process took the longer and was confined closer
to the surface the more reduced the exposed sediment had been
before. Resuspension of eroded sediment in aerated lake water
did not cause a significant oxidation or reduction of iron. After re-deposition, the oxic-anoxic interface in the re-sedimented
material shifted to about 2 mm depth within 30 min, causing an
oxygen flow into the sediment. During the following 12 h, the
oxygen penetration depth and the oxygen flow rate into the re-deposited sediment did not change any further, and no oxygen was
produced in the light. Ferric iron was reduced during the first day
after re-deposition, and partly re-oxidized during the second day.
The extent of reduction was stronger and the extent of oxidation
weaker the more reduced the resuspended sediment was before.
Oxic conditions in the sediment surface were established faster
and ferrous iron was oxidized to a larger extent after erosion of
sediment than after resuspension and sedimentation. В© Springer
2005.
1651 Trace metal profiles in the varved sediment of an Arctic
lake
Outridge P.M., Stern G.A., Hamilton P.B. et al. Geochimica et
Cosmochimica Acta 2005 69/20 (4881-4894)
Varved (annually-laminated) sediments offer a rare and physically undisturbed archive of past trace metal deposition and limnological conditions. Here, a high-resolution 1,300 year record
of metal accumulation is presented from a varved lake sediment
on Devon Island in the Canadian High Arctic. Down-core concentration profiles of Cd, Cu and Zn were positively correlated
(P < 0.01) with organic C (Cd, Zn) or with leachable Fe (Cu),
while distinct sub-surface peaks of these metals coincided with
those of Fe, S and other redox-sensitive elements such as Co,
Cr and U. The fluxes of these metals since 1854 were correlated
with elements such as Ca, Al and La (P < 0.001) which are predominantly of local geological origin. Furthermore, the Cd, Cu
and Zn patterns did not match concurrent records in Greenland
Summit ice over the last century, nor global industrial emission
histories. These facts suggest that inputs from local geological
sources, coupled with some degree of post-depositional mobility or association with organic matter inputs, explain the metalsвЂ™
sedimentary profiles, which were apparently not affected by longrange atmospheric metal pollution. Mercury concentrations were
strongly correlated with total diatom abundance over the last 400
yrs, especially during the 20th Century when a two-fold increase
in Hg concentrations and a four order-of-magnitude increase in
diatoms occurred in tandem. Since 1854, 81% of the variation
in Hg flux was associated with diatom and Ca fluxes. A similar
correspondence between Hg and diatoms was found in a second
lake nearby, confirming that the relationship was not unique to the
main study lake. Recent Hg increases in Arctic and sub-Arctic
lakes have been attributed to global anthropogenic Hg emissions.
We propose an alternative hypothesis for High Arctic lakes: the
recent Hg increases may be partly or entirely the product of
elevated rates of Hg scavenging from the water column caused
by markedly greater algal productivity, which in turn was driven
by accelerating climate warming during the 20th Century. Given
the important environmental assessment and policy implications
if the alternative hypothesis is true, the possible effects of climate
warming on sedimentary Hg fluxes in this region deserve further
study. Copyright В© 2005 Elsevier Ltd.
1652 Sea bottom anoxia in the Archipelago Sea, northern
Baltic Sea - Implications for phosphorus remineralization at
the sediment surface
Virtasalo J.J., Kohonen T., Vuorinen I. and Huttula T. Marine
Geology 2005 224/1-4 (103-122)
The effects of the hydrophysical environment on oxygen conditions and P remineralization at sediment surface were studied in
the Archipelago Sea, northern Baltic Sea. At 94 sites, the water
column was profiled for conductivity, temperature and oxygen,
and the topmost sediment was collected for P and C fractions
and (oxy)hydroxide Fe analysis. The near-bottom water and
sediment parameters as well as visual observations on the vertical
colour distribution in the sediment cores were used to statistically
classify the sediment surfaces into oxic, anoxic and suboxic
(fluctuating oxygen conditions) bottoms. The anoxic bottoms
occurred in the basins with water depths less than 47 m, and the
suboxic bottoms were most common in the basins with depths
314
SEDIMENTOLOGY
between 20-60 m, while the oxic bottoms dominated in the depths
over 60 m. It was concluded that the preferential development
of oxygen deficiency in the shallow basins results from the combined effects of complex topography and seasonal temperature
stratification on both vertical and lateral bottom water exchange.
In the anoxic bottoms, C / P ratios suggest enhanced release
of P compared to the oxic and suboxic bottoms. In the suboxic
bottoms, high inorganic P concentrations and the strong coupling
between P and Fe suggest active transformation of organic P to
the inorganic P phases, probably due to the fluctuating oxygen
conditions. Differences in the spatial distribution of the P, C
and Fe were insignificant except for detrital P, which decreased
seawards. В© 2005 Elsevier B.V. All rights reserved.
1653 Revisiting the rare earth elements in foraminiferal tests
Haley B.A., Klinkhammer G.P. and Mix A.C. Earth and Planetary Science Letters 2005 239/1-2 (79-97)
Are the rare earth elements (REEs) in foraminifera a valuable
proxy for use in paleoceanographic and climate change studies?
In order to investigate this, we attempted a comprehensive study
of REEs in planktonic and benthic foraminifera. Several different cleaning protocols were tested. Although the hydroxylamine
used to clean all foraminifera in this study removes an unidentified source of REE contamination, it seems to remobilize metal
oxides that are otherwise unaffected in flow-through dissolution.
The calculated REE distribution coefficients, KD(REE) s, are between 100 and 500 for both planktonic and benthic foraminifera.
These KD s are high compared to other elements in biogenic
calcite but can be explained through a general model of element
incorporation during foraminiferal calcification. From data taken
from eight core tops in the southeast Pacific, we conclude that the
REEs in planktonic foraminifera are, indeed, useful as a proxy for
upper ocean water mass and mixed layer biogenic productivity.
Alternatively, the REEs in benthic foraminifera are useful as a
proxy for carbon flux to the sea floor. These proxies should be
robust down core unless the sediments have undergone anoxic
diagenesis, which stabilizes Fe carbonate thus overprinting the
primary REE signature. However, it is clear from REE distributions in foraminiferal tests if anoxic conditions have occurred. В©
2005 Elsevier B.V. All rights reserved.
1654 Fluid sources, fluid pathways and diagenetic reactions across an accretionary prism revealed by Sr and B
geochemistry
Teichert B.M.A., Torres M.E., Bohrmann G. and Eisenhauer A.
Earth and Planetary Science Letters 2005 239/1-2 (106-121)
ODP Leg 204, which drilled at Hydrate Ridge, provides unique
insights into the fluid regime of an accretionary complex and delineates specific sub-seafloor pathways for fluid transport. Compaction and dewatering due to smectite-illite transition increase
with distance from the toe of the accretionary prism and bring
up fluids from deep within the accretionary complex to sampled
depths ( 600 mbsf). These fluids have a distinctly non-radiogenic strontium isotope signature indicating reaction with the
oceanic basement. Boron isotopes are also consistent with a
deep fluid source that has been modified by desorption of heavy
boron as clay minerals change from smectite to illite. One of
three major horizons serves as conduit for the transport of mainly
fluid. Our results enable us to evaluate fluid migration pathways
that play important roles on massive gas hydrate accumulations
and seepage of methane-rich fluids on southern Hydrate Ridge.
В© 2005 Elsevier B.V. All rights reserved.
1655 Elemental composition of calcites in late Quaternary
pedogenic calcretes from Gujarat, western India
Khadkikar A.S. Journal of Asian Earth Sciences 2005 25/6 (893902)
Pedogenic calcretes commonly exhibit clotted micrite, circumgranular calcite (grain coats) and microspar/spar veins. The
three calcite-types with different dimensions were analyzed for
their magnesium content to determine the relationship between
crystal elongation and magnesium incorporation. The results
show a very low MgO content for grain coats and microspars and
high values for clotted micrite indicating that the ideal kinetic
model does not hold true and several variables govern the end
composition of calcites. The magnesium concentrations of meteoric calcites are genetically linked to the evolutionary history
of the soil and climate. Grain coats, which are elongated calcites,
contain the least amount of Mg and is related to the initial stages
of pedogenesis wherein the limiting factor is the Mg/Ca ratio of
the parent fluid. Lower magnesium contents arise due to smaller
quantities of Mg being released during incipient weathering. Micrite morphology and composition is controlled by the greater
availability of Mg ions through weathering, higher pCO2 in soil
due to increased time-dependent soil respiration, which causes a
rise in calcite precipitation rates and clay authigenesis. This in
turn exerts a physical control on morphology by occluding pore
space and providing numerous nuclei for calcite precipitation.
The wide variability in spar cements is inherently controlled by
inhomogeneties in parent fluid compositions with lower-thanmicrite values on account of slower precipitation rates. В© 2004
Elsevier Ltd. All rights reserved.
1656 Characterization and origin of Fe3 +- montmorillonite
in deep-water calcareous sediments (Pacific Ocean, Costa
Rica margin)
Gaudin A., Buatier M.D., Beaufort D. et al. Clays and Clay
Minerals 2005 53/5 (452-465)
Millimetric to centimetric green grains widespread in pelagic calcareous sediments recovered at a water depth of 3000 in near the
Costa Rica margin were studied by X-ray diffraction, scanning
electron microscopy (SEM), transmission electron microscopy
(TEM) and Fourier transform infrared spectroscopy. Samples
were collected, during the Ticoflux II expedition, from the upper
bioturbated part of four sedimentary cores (0.13-3.75 in below
seafloor). The sediments are calcareous and siliccous nanofossil
oozes (coccoliths, diatoms, radiolarians, etc.). Green grains show
generally a concentric zoning with a green rim in which smectite
largely predominates over pyrite and a black core in which pyrite
is prevalent. Observations by SEM indicate that this zoning
results from a progressive inward alteration and replacement of
the accumulations of pyrites by smectites. The high-resolution
TEM observations of the smectite-pyrite interfaces suggest that
the replacement of pyrites by smectite occurs through a dissolution-precipitation process with the formation of a gel. The pyrite
matrix is composed of a huge number of very small (0.5-2 m)
pyrite octahedra, a typical texture resulting from the pyritization
of organic material in early diagenetic environments. The accurate mineral ogical and crystal chemical characterization of the
smectites indicate that they are Fe3+ -montmorillonites (Fe3+ -rich
smectite with a dominant octahedral charge, rarely recorded in the
literature). The formation of such Fe3+ -montmorillonites forming green grains could be explained by two successive diagenetic
redox stages: (1) reducing stage: early pyritization of the organic
matter by microbial reduction within reducing micro-environments; (2) oxidizing stage: Fe3+ -montmorillonite crystallized
in space liberated after dissolution of pyrite connected with the
rebalancing of the redox conditions of the micro-environments
with the oxidizing surrounding sediments. Copyright В© 2005,
The Clay Minerals Society.
1657 REE and Nd of clay fractions in sediments from the
eastern Pacific Ocean: Evidence for clay sources
Liu J., Shi X., Chen L. et al. Science in China, Series D: Earth
Sciences 2005 48/5 (701-712)
Clay fractions in the non-calcareous surface sediments from the
eastern Pacific were analyzed for clay minerals, REE and 143 Nd/
144 Nd. Montmorillonite/illite ratio (M/I ratio), total REE contents
( REE), LREE/HREE ratio and cerium anomaly ( Ce) may effectively indicate the genesis of clay minerals. Clay fractions
with M/I ratio >1, Ce <0.85, REE >400 g/g, LREE/HREE
ratio 4, and REE patterns similar to those of pelagic sediments
are terrigenous and autogenetic mixed clay fractions and contain
more autogenetic montmorillonite. Clay fractions with M/I ratio
<1, Ce=0.86 to 1.5, REE=200 to 350 g/g, LREE/HREE ratio
6 and REE distribution patterns similar to that of China loess
are identified as terrigenous clay fraction. The 143 Nd/144 Nd ratios
or Nd values of clay fractions inherit the features of terrigenous
sources of clay minerals. Clay fractions are divided into 4 types
according to Nd values. Terrigenous clay minerals of type I
with the Nd values of -8 to -6 originate mainly from North
American fluvial deposits. Those of type II with the Nd values
of -9 to -7 are mainly from the East Asia and North American
SEDIMENTOLOGY
fluvial deposits. Those of type III with Nd values of -6 to -3
could come from the central and eastern Pacific volcanic islands.
Those of type IV with Nd values of -13 to -12 may be from
East Asia eolian. The terrigenous and autogenetic mixed clay
fractions show patchy distributions, indicating that there are volcanic or hot-spot activities in the eastern Pacific plate, while the
terrigenous clay fractions cover a large part of the study area,
proving that the terrigenous clay minerals are dominant in the
eastern Pacific. Copyright by Science in China Press 2005.
1658 Trace elements in streambed sediments of small subtropical streams on OвЂ™ahu, HawaiвЂ™i: Results from the USGS
NAWQA program
De Carlo E.H., Tomlinson M.S. and Anthony S.S. Applied
Geochemistry 2005 20/12 (2157-2188)
Data are presented for trace element concentrations determined
in the <63 m fraction of streambed sediment samples collected
at 24 sites on the island of OвЂ™ahu, HawaiвЂ™i. Sampling sites were
classified as urban, agricultural, mixed (urban/agricultural), or
forested based on their dominant land use, although the mixed
land use at selected sampling sites consisted of either urban and
agricultural or forested and agricultural land uses. Forest dominated sites were used as reference sites for calculating enrichment
factors. Trace element concentrations were compared to concentrations from studies conducted in the conterminous United States
using identical methods and to aquatic-life guidelines provided
by the Canadian Council of Ministers of the Environment. A
variety of elements including Pb, Cr, Cu and Zn exceeded the
aquatic-life guidelines in selected samples. All of the Cr and Zn
values and 16 of 24 Cu values exceeded their respective guidelines. The potential toxicity of elements exceeding guidelines,
however, should be considered in the context of strong enrichments of selected trace elements attributable to source rocks in
HawaiвЂ™i, as well as in the context of the abundance of finegrained sediment in the streambed of OвЂ™ahu streams. Statistical
methods including cluster analysis, Kruskal-Wallis non-parametric test, correlation analysis, and principal component analysis
(PCA) were used to evaluate differences and elucidate relationships between trace elements and sites. Overall, trace element
distributions and abundances can be correlated to three principal
sources of elements. These include basaltic rocks of the volcanic
edifice (Fe, Al, Ni, Co, Cr, V and Cu), carbonate/seawater derived
elements (Mg, Ca, Na and Sr), and elements enriched owing to
anthropogenic activity (P, Sn, Cd, Sn, Ba and Pb). Anthropogenic
enrichment gradients were observed for Ba, Cd, Pb, Sn and Zn
in the four streams in which sediments were collected upstream
and downstream. The findings of this study are generally similar
to but differ slightly from previous work on sediments and suspended particulate matter in streams, from two urban watersheds
of OвЂ™ahu, HawaiвЂ™i. Inter-element associations in the latter were
often stronger and indicated a mixture of anthropogenic, agricultural and basaltic sources of trace elements. Some elements
fell into different statistical categories in the two studies, owing
in part to differences in study design and the hydrogeological
constraints on the respective study areas.
1659 Sequential Factor Analysis as a new approach to multivariate analysis of heterogeneous geochemical datasets: An
application to a bulk chemical characterization of fluvial deposits (Rhine-Meuse delta, the Netherlands)
Van Helvoort P.- J., Filzmoser P. and Van Gaans P.F.M. Applied
Geochemistry 2005 20/12 (2233-2251)
Sequential Factor Analysis (seqFA) is presented here as an enhanced alternative to multivariate factorial techniques including
robust and classical Factor Analysis (FA) or Principal Component Analysis (PCA). A geochemical data set of 145 sediment
samples from very heterogeneous, mainly riverine, deposits of
the Rhine-Meuse delta (The Netherlands) analyzed for 27 bulk
parameters was used as a test case. The innovative approach
explicitly addresses the priority issues when performing PCA or
FA: heterogeneity and overall integrity of the data, the number
of factors to be extracted, and which optimum minimal set of
key variables to be included in the model. The stepwise decision
process is based on quantitative and objectively derived statistical
criteria, yet also permitting arguments based on geochemical expertize. The results show that seqFA, preferably in combination
with robust methods, yields a highly consistent factor model, and
315
is favorable over classical methods when dealing with heterogeneous data sets. It optimizes rotation of the factors, and allows
the extraction of less distinct factors supported by only a few
variables, thus uncovering additional geochemical processes and
properties that would easily be missed with other approaches.
The identification of key variables simplifies the geochemical interpretation of the factors, and greatly facilitates the construction
of a geochemical conceptual model. For the case of the fluvial
deposits, the conceptual model effectively describes their bulk
chemical variation in terms of a limited number of governing
processes. В© 2005 Elsevier Ltd. All rights reserved.
1660 Late Holocene geochemical history inferred from Sambhar and Didwana playa sediments, Thar Desert, India:
Comparison and synthesis
Roy P.D., Smykatz- Kloss W. and Sinha R. Quaternary International 2005 144/1 (84-98)
The Sambhar and Didwana playas from the eastern margin of
the Thar Desert (annual precipitation of 300-450 mm) have been
investigated for mineralogy, major and trace element geochemistry of near surface sediments. Geochemical data and evaporite
mineralogy of sediments from the playa surface and shallow
depths provide insight to the present-day geochemical processes
and the different vertical phases of pore water activity. Detrital
minerals from both the playas reflect igneous and metamorphic
source rocks in their catchments. The zeolite type mineral, analcime (NaAlSi2 O6 H2 O) is assumed to be authigenic in origin,
a product of chemical reaction between the hypersaline brine
and detrital feldspars. The evaporite mineralogy is dominated
by halite, calcite and dolomite. Major differences between the
evaporite mineralogy of the surface sediments of two playas are
the occurrence of trace amounts of the H2 O-bearing carbonate,
trona (Na3 H(CO3 )2 2H2 O), in the Didwana and K- and Mgbearing sulphate and chloride minerals e.g. polyhalite (K2 MgCa2
(SO4 )4 2H2 O), carnallite (KMgCl3 6H2 O), and sylvite (KCl) in
the Sambhar. Based on the distribution of major and trace elements, the surface sediments from both playas are divided into
three geochemical zones. Fed by river and rainwaters, the playa
surfaces show enrichment of insoluble cations and hydrolysates
in the outermost zone and soluble oxides and cations in the
innermost zone. Further, the shallow depth profiles are also
divided into distinct geochemical zones based on the elemental
ratios. The sub-recent zone I reflects low chemical weathering
and higher aeolian input, the middle zone II indicates relatively
higher weathering index and zone III, enriched in evaporites,
also shows low chemical weathering. Despite the fact that the
Sambhar and Didwana are separated only by 50 km, they show
significant differences in terms of evaporite mineralogy and inorganic composition of surface sediments. We interpret this to
be a manifestation of local variations in precipitation, inflow
and aeolian influx. В© 2005 Elsevier Ltd and INQUA. All rights
reserved.
Sedimentary environments terrestrial
1661 Sedimentation problems and management strategies
of Sanmenxia Reservoir, Yellow River, China
Wang G., Wu B. and Wang Z.- Y. Water Resources Research
2005 41/9 (1-17)
[1] Reservoir sedimentation management is of critical importance
for the sustainable development of surface water resources. Sanmenxia Dam, located on the middle reach of the Yellow River,
in China, is notorious for its severe sedimentation problems.
Because of the alarming rate of loss of reservoir storage capacity
and the unacceptable negative impact induced by the rapid upstream extension of sediment deposited in the riverвЂ™s backwater
region, the dam has been reconstructed to provide high sediment
releasing capacity, and the dam operation has been changed in
order to achieve a balance between sediment inflow and outflow.
As a result, the dam is still providing the basin with flood control,
irrigation, and hydropower generation, even though some benefits are lower than the original design. Complex sedimentation
processes in response to the dam reconstruction and changes
316
SEDIMENTOLOGY
of dam operation are discussed in this paper. The engineering
experiences and management practices of Sanmenxia Dam are
valuable assets to the sustainable use of reservoirs built on sediment-laden rivers. Copyright 2005 by the American Geophysical
Union.
1662 Sediment provenances and drainage evolution of the
Neogene Amazonian foreland basin
Roddaz M., Viers J., Brusset S. et al. Earth and Planetary
Science Letters 2005 239/1-2 (57-78)
During the Middle-Late Miocene, tidal sedimentation was the
rule in the Amazon foreland basin. The Amazon foreland basin
became emerged in the Late Miocene-Pliocene times. In this
study, trace element chemistry (n = 104) and Nd-Sr isotopic
systematic (n = 30) are used to constrain the provenance of the
Miocene tidal sediments and of the Late Miocene-Pliocene fluvial sediments. Neogene Amazonian foreland basin sediments
are the result of a mixing between Andean andesitic volcanic
rocks and cratonic shield rocks. The south Amazonian foreland
basin (SAFB) sediments are the result of long-term weathering, recycling, and erosion of the Brazilian shield and Andean
Paleozoic/Mesozoic rocks also Brazilian shield in provenance.
Compared with north Amazonian foreland basin (NAFB) sediments, SAFB sediments are more felsic. NAFB sediments have 3
distinct signatures: i) an upper crust signature with trace element
characteristics similar to PAAS and UCC and with Nd(0) values
between - 8 and - 11.9; ii) an arc andesitic rock signature with
high Cr/Th ratios, low Eu anomalies, low Th/Sc ratios and Nd(0)
values between - 3 and - 5; and iii) a cratonic signature with high
Eu anomalies and Zr/Sc ratios and with a very low Nd(0) value
(-15.5). Our data indicate that most of the basic detritus came
from the Ecuadorian Andes. In the distal part of the NAFB, the
successive uplifts of the Iquitos forebulge were responsible for
Late Miocene to Pliocene divide between Andean and cratonic
drainage systems. The modern "Amazon River" drainage network is no younger than the Pliocene. В© 2005 Elsevier B.V. All
rights reserved.
1663 Distribution of high-level alluvial deposits in the valley
and ridge of Polk County, southeastern Tennessee: Implications for river history and drainage evolution
Mills H.H., Sumners D.N., Hart E.A. and Li P. Southeastern
Geology 2005 44/1 (37-44)
Surficial mapping based on digital soil maps along the Hiwassee
and Ocoee Rivers in western Polk County, Tennessee, shows
almost 100 square kilometers of alluvium. By far the most
extensive is high-level alluvium resting on carbonate bedrock,
mainly on the Knox Group. This old alluvium covers rolling
topography at elevations of roughly 15 m or greater above the
modern river level (ARL), extending to 80 m ARL locally. It
is highly weathered, with B horizons having clay percentages
exceeding 50 percent and Munsell hues of typically 2.5YR. Sandstone clasts, where present, generally are decomposed. Deposits
lower than 15 m ARL occur on floodplains and low terraces are
much less weathered, with clay percentages less than 30 and
colors no redder than 7.5YR. Pebbles and cobbles of vein quartz
attest to the origin of most alluvium in the Blue Ridge province.
Such clasts become less common with increasing height ARL,
and at the highest levels regolith consists of scattered quartz clasts
mixed with carbonate residuum. Alluvial deposits generally occur within 4 km of the main rivers. An exception is a band of
high-level alluvium extending from the Ocoee south-southwesterly to the Conasauga River near the Tennessee-Georgia border.
This band crosses a prominent divide between the Tennessee
and Coosa River basins where only small, local streams flow
today. Its presence suggests either that the Conasauga, currently
a tributary to the Coosa, once flowed north to the Tennessee
River, or else that the Ocoee, now a tributary of the Tennessee,
once flowed south to the Coosa.
1664 Deposition of playa windblown dust over geologic time
scales
Pelletier J.D. and Cook J.P. Geology 2005 33/11 (909-912)
Thick eolian deposits are commonly observed beneath desert
pavements downwind of dust-emitting playas. These deposits
play an important role in piedmont-surface evolution, controlling
surface hydrologic conductivity and rates of pedogenesis. To
better understand the factors controlling the spatial distribution
of eolian deposition, we developed a numerical model that treats
deposition from spatially distributed playa sources using analytic
point-source solutions for deposition from a Gaussian plume.
The model also accounts for complex downwind topography. As
a test case, model predictions were compared to eolian deposit
thicknesses on Eagle Mountain piedmont, southern Amargosa
Valley, California, which receives dust from nearby Franklin
Lake playa. The close relationship between the model predictions and mapped thicknesses suggests that eolian transport and
deposition can be modeled from basin to regional scales within
this framework. These results have important implications for
hydrologic, pedogenic, and air-quality problems. В© 2005 Geological Society of America.
1665 Fractal river networks of Southern Africa
Stankiewicz J. and de Wit M.J. South African Journal of Geology
2005 108/3 (333-344)
Fractals and scaling laws abound in nature, and it is said that
geometry of river networks and basins is an epitome of this. This
study investigates how, in the southern section of the tectonically
unique African continent, scaling parameters and deviations from
вЂ�perfect fractal patternsвЂ™ relate to parameters like geomorphology
through which the river flows, and the underlying geology. A
number of river network scaling laws and scaling parameters have
been put forward, but it has been suggested that all river networks
can be divided into universality classes represented by just 2 of
these scaling parameters. One of these is the fractal dimension
of individual streams, usually labelled d and having a value of
1.1. The other parameter, HackвЂ™s exponent h, expresses the
dependence of stream length (l) on drainage area (a) via HackвЂ™s
Law l = cah . There is no universal value for h. Different networks
often have different values for h, and inside a given network the
parameter is often observed to change with scale. We use the
natural laboratory of networks in southern Africa to investigate
the variations in HackвЂ™s exponent and find evidence to confirm
the existence of scaling regimes. We attempt to explain these
variations in scaling using the regime model of Dodds and Rothman (2000). At the smallest scale we find that non-convergent
mountain streams exist in different settings, but their spacing is
determined by underlying rock type. in this type of drainage
a 1, and hence h 1. Once streams begin to converge, the
value of h drops, and is inversely correlated to the roughness
of the underlying topography. This trend stops once basin sizes
reach a threshold value, above which basins may be self-similar.
This threshold varies in individual networks. In the smoothest
topographies it occurs as low as 400 km2 , but can occur as high
as 1400 km2 in other networks. While we have identified a number of guidelines for correlating scaling parameters with basin
settings, there exist significant variations around these guidelines
which we can only attribute to randomness, or small variations
in the initial conditions during the initial formation of the river
basins. В© 2005 Geological Society of South Africa.
1666 A lithofacies terrain model for the Blantyre Region:
Implications for the interpretation of palaeosavanna depositional systems and for environmental geology and economic
geology in southern Malawi
Dill H.G., Ludwig R.- R., Kathewera A. and Mwenelupembe J.
Journal of African Earth Sciences 2005 41/5 (341-393)
The Blantyre City Area is part of the African savanna in southern Malawi. Sedimentological, geomorphological, chemical and
mineralogical studies were conducted to create a lithofacies terrain model. The project involves mapping, cross-sectioning,
grain size, heavy mineral analysis, XRD and the study of sedimentary textures under the petrographic microscope. These
classical techniques were combined with GIS-based field and office works. The combined efforts led to 2-D maps and 3-D block
diagrams that illustrate the geomorphological and sedimentological evolution of the landscape in southern Malawi during
the late Mesozoic and Cenozoic. The results obtained through
integrated geomorphological-sedimentological studies form the
basis for land management (planning of residential areas, waste
disposal sites, assessment of bearing capacity of rocks), geohazard prediction (delineation of high risk zones in terms of mass
flow and inundation) and the evaluation of high-place (ceramic
raw materials) and high-unit value (placers of precious metals
SEDIMENTOLOGY
and gemstones) mineral commodities in the study area. The
study addresses regional and general aspects alike. In regional
terms, the study aimed at unraveling the evolution of landforms
at the southern end of the East African Rift System during the
most recent parts of the geological past. Four stages of peneplanation were established in the working area. Planation was
active from the Cretaceous to the Quaternary (stage I: early to
mid-Cretaceous, stage II: early Tertiary, stage III: early to midTertiary, stage IV: mid- to late Tertiary). During the most recent
parts of the Quaternary, strong fluvial incision was triggered by
the base-level lowering of the Shire River. Geomorphological
alteration of the landscape goes along with a phyllosilicate-sesquioxide transformation from minerals indicative of more acidic
meteoric fluids (e.g., gibbsite, kaolinite) to those typical of more
alkaline conditions (e.g. smectite, vermiculite, hydrobiotite).
In addition, the investigation is to provide some characteristic
features suitable for the recognition and interpretation of terrestrial environments resembling the present-day savanna in the
ancient sedimentary record: (1) Conspicuous bimodality in the
grain-size distribution. (2) High degree of gravel roundness. (3)
Boulder fields (basal conglomerates) with fitting breccias and no
rotation of structural elements. (4) Poor to very poor sorting of
siliciclastics. (5) Stratification is rare; if present only in sandy
beds with antidune and tabular cross-bedding at low angle prevailing over crossbedding at high angle. (6) Grading rare; in
arenaceous deposits poorly developed FU sequences, in rudites
poorly developed CU sequences, locally with surface armoring.
(7) Directional sedimentary structures in coarse-grained deposits
are unimodal. Fabric types: a(t)b(i) and a(p)b(i); shear planes
indicative of slide may be present. (8) Ribbon-shaped architectural elements prevail over channel-like types. Bounding surfaces/unconformities are uneven to wavy and more widespread
than scour-and-pool structures. (9) Fine-grained carbonaceous
interbeds are restricted to shallow depressions. (10) Etch marks
such as tafonis, flutes, honeycomb textures are common. (11)
Placer deposits of metallic and non-metallic mineral commodities
are abundant. (12) Alucretes and ferricretes of bog iron (ferrihydrite & gt; goethite) and lateritic (goethite > ferrihydrite) types
are common, calcitic freshwater limestones and gypcretes are
scarce. (13) Kandite-group minerals "in" (relic), smectite-group
minerals "in", vermiculite "in" (recent), mica-group minerals
"out". В© 2005 Elsevier Ltd. All rights reserved.
Sedimentary environments - coastal
and shallow marine
1667 The interplay of eustasy, climate and human activity in
the late Quaternary depositional evolution and sedimentary
architecture of the Po Delta system
Stefani M. and Vincenzi S. Marine Geology 2005 222-223/1-4
(19-48)
The late Pleistocene and Holocene environmental evolution and
sequence stratigraphic architecture of the Po Delta region, Northern Italy, are examined. The study units record the depositional
evolution from lowstand continental accumulation to marine
transgression and highstand progradation. Interpretation of the
high-resolution, three-dimension geological mapping of the central Po Delta area was framed within the evolution of the whole of
the delta region, stretching from Venice Lagoon to the South of
Ravenna. The development of the delta lobes was correlated with
the fluvial drainage history. A discussion on the different auto and
allocyclic mechanisms controlling the depositional evolution and
a quantitative estimation of the changing depositional rates are
also provided. Outcrop study was based on field surveying and
on the analysis of aerial photography, topographic micro-relief,
historical cartography, archaeological and historiographic data.
Subsurface analysis was based on stratigraphic coring and cone
penetration testing. During the last glacial lowstand, the modern
coastal region was the site of middle alluvial plain sedimentation. Deglaciation and early transgression were associated with
an erosive disconformity development. In the modern coastal
area, transgressive accumulation started between 10 and 9000
yr BP. Back-stepping fluvial and brackish marsh deposits were
followed by delta-estuarine sand bodies, influenced by the last
317
important eustatic rise pulses. Transgression climaxed at about
5500 yr BP, during a warm climate phase. Early highstand saw
the growth of large sand spits and barrier islands, progressively
turning the previous bays into confined lagoons. At about 35003000 yr BP, a particularly active meteo-marine regime profoundly
affected the depositional dynamics. Etruscan and Roman times
were characterised by a warm climate and by riverine stability
associated with the development of a large delta lobe. At around
1500 yr BP, transition toward moister and cooler conditions and
the abandoning of the Roman Empire hydraulic works coincided
with important drainage network instability. The modern delta
lobe was induced 400 years ago by an artificial fluvial-mouth cut.
The early evolution of the lobe recorded very high accumulation
rates. The modern fragile environmental situation is characterised by strong coastal erosion and difficult management. В© 2005
Elsevier B.V. All rights reserved.
1668 Event beds in the recent prodelta stratigraphic record
of the small flood-prone Bonea Stream (Amalfi Coast, Southern Italy)
Budillon F., Violante C., Conforti A. et al. Marine Geology 2005
222-223/1-4 (419-441)
Seismic interpretation of about 150 km of high resolution Sonar
Chirp lines, matched with cores collected off the Bonea Stream
mouth (Salerno Bay, Southern Tyrrhenian Sea) were used in the
detection of event beds interlayered in the pelitic Late Holocene
shelf wedge. Grain fabric, textures and absolute dating of core
sediment allowed to identify the most recent event bed as being
the coarse deposit that settled following the disastrous flood of the
Bonea Stream in 1954 A.D. Below this event bed, three others,
consisting of sharp-based and graded sand layers, were recognized as well. Their lithology, texture and lateral geometry point
to a diverse dynamic of deposition, involving the reworking and
winnowing of fluvial and littoral sand such as seastorm-induced,
downflow currents. The unusual thickness of tempestite sandy
layers has been linked to the large availability of sand delivered
to the coastal system by recurrent floods in the area and to the
fast burial rate. Magnetic susceptibility correlations calibrated
by a dated core, by 210 Pb and 137 Cs geochronology and by the
1822 A.D. Vesuvius tephra and seismic stratigraphic evidences,
led to constrain these events to the last 1000 yr. В© 2005 Elsevier
B.V. All rights reserved.
1669 Autogenic cyclicity of foreset sorting in experimental
Gilbert-type deltas
Kleinhans M.G. Sedimentary Geology 2005 181/3-4 (215-224)
Gilbert-type deltas are commonly characterised by steep foreset
bedding. Changes in the foreset characteristics such as grain
size, grading, alternating sand and gravel are often interpreted
as records of changes of base level or sediment input due to
diurnal, seasonal or climatic forcing. To aid such interpretations,
an important question is to what extent cyclicity in the foreset
characteristics can be explained by autogenic processes rather
than exogenic forcing. Experimental deltas were generated with
gravelly sand under constant boundary conditions and a varying
width-depth ratio of the feeder system. The foresets of the narrow
feeder system are regular and show gradual upward fining. The
foresets of the wide feeder system, in contrast, show quasi-cyclic
patterns of coarsening and fining during the delta progradation.
The cyclicity is caused by the emergence of a channelised point
feeder system with migrating gravel side bars, which distributes
the sand and gravel laterally in a non-uniform manner. This
spectacular change of foreset architecture is fully explained by
the autogenic response of the feeder system to the width. These
experiments are contrasted with experiments and data from literature in the framework of the delta classification of Postma
[Postma, G., 1990. Depositional architecture and facies of river
and fan deltas: a synthesis. In: Colella, A. and Prior, D.B. (eds),
1990. Coarse-grained Deltas. Spec. Publ. 10 of the Int. Ass. of
Sedimentologists, Blackwell Scientific, Oxford, UK, 13-28]. В©
2005 Elsevier B.V. All rights reserved.
318
SEDIMENTOLOGY
Sedimentary environments - oceanic
1670 Sedimentary architecture of a Plio-Pleistocene protoback-arc basin: Wanganui Basin, New Zealand
Proust J.- N., Lamarche G., Nodder S. and Kamp P.J.J. Sedimentary Geology 2005 181/3-4 (107-145)
The sedimentary architecture of active margin basins, including
back-arc basins, is known only from a few end-members that
barely illustrate the natural diversity of such basins. Documenting more of these basins types is the key to refining our understanding of the tectonic evolution of continental margins. This
paper documents the sedimentary architecture of an incipient
back-arc basin 200 km behind the active Hikurangi subduction
margin, North Island, New Zealand. The Wanganui Basin (WB)
is a rapidly subsiding, Plio-Pleistocene sedimentary basin located
at the southern termination of the extensional back-arc basin of
the active Central Volcanic Region (TVZ). The WB is asymmetric with a steep, thrust-faulted, outer (arc-ward) margin and
a gentle inner (craton-ward) margin. It contains a 4-km-thick
succession of Plio-Pleistocene sediments, mostly lying offshore,
composed of shelf platform sediments. It lacks the late molasselike deposits derived from erosion of a subaerial volcanic arc and
basement observed in classical back-arc basins. Detailed seismic
stratigraphic interpretations from an extensive offshore seismic
reflection data grid show that the sediment fill comprises two
basin-scale mega-sequences: (1) a Pliocene (3.8 to 1.35 Ma),
sub-parallel, regressive "pre-growth" sequence that overtops the
uplifted craton-ward margin above the reverse Taranaki Fault, and
(2) a Pleistocene (1.35 Ma to present), divergent, transgressive,
"syn-growth" sequence that onlaps: (i) the craton-ward high
to the west, and (ii) uplifted basement blocks associated with
the high-angle reverse faults of the arc-ward margin to the east.
Along strike, the sediments offlap first progressively southward
(mega-sequence 1) and then southeastward (mega-sequence 2),
with sediment transport funnelled between the craton- and arcward highs, towards the Hikurangi Trough through the Cook
Strait. The change in offlap direction corresponds to the onset
of arc-ward thrust faulting and the rise of the Axial Ranges at
ca 1.75 Ma, resulting in 5100-5700 m of differential subsidence
across the fault system. Sedimentation has propagated south- to
southeast-ward over the last 4 Myrs at the tip of successive backarc graben, volcanic arcs and the associated thermally uplifted
parts of the North Island, following the southward migration
of the Hikurangi subduction margin. Subsidence occurred by
mantle flow-driven flexure, the result of active down-drag of the
lithosphere by locking of the Hikurangi subduction interface and
sediment loading. The WB is considered to be a proto-back-arc
basin that represents the intermediate stage of evolution of an
epicratonic shelf platform, impacted by active margin processes.
В© 2005 Elsevier B.V. All rights reserved.
Applied sedimentology
1671 Manganese and iron accumulation in a eutrophic, submontane dam reservoir - The role of speciation
Szarek-Gwiazda E. Oceanological and Hydrobiological Studies
2005 34/3 (125-139)
The manganese and iron in the water and sediments of the submontane, eutrophic Dobczyce Dam Reservoir (southern Poland)
was partitioned. Manganese and iron occurred mainly in the
particulate phases in the water. In the sediments, approximately
77% of Mn was bound to exchangeable carbonate and easily reducible fractions, whereas approximately 90% of Fe was bound
to moderately reducible fractions and residues. The cumulation
coefficient (K) indicated that Mn, the more "mobile" element,
accumulated in lower amounts in the sediments (K=7200) than
did Fe (K = 51000). Element partitioning in the sediments was
an important factor in determining the level of accumulation.
1672 Occurrence of pesticides, polychlorinated biphenyls
(PCBs), and heavy metals in sediments from the Dniester
River, Moldova
Sapozhnikova Y., Zubcov E., Zubcov N. and Schlenk D. Archives
of Environmental Contamination and Toxicology 2005 49/4 (439448)
The aim of this study was to evaluate sediments of the Dniester River, in the former Soviet republic of Moldova, for the
occurrence of agricultural pesticides, polychlorinated biphenyls
(PCBs), and heavy metals. In October 2001, sediment samples
were collected at three locations of the Dniester River: upstream,
downstream, and at the tributary of the River Byk. DDT and its
metabolites were observed most frequently. Total DDT sediment
concentrations ranged from 8.2 to 34.7 ng/g dry weight with the
highest average concentration detected at the tributary location.
Heptachlor epoxide (< 0.2-3.0 ng/g dry weight), chlordane (<
0.1-6.1 ng/g dry weight), endrin (< 0.2-2.5 ng/g dry weight),
phosalone (< 0.2-1.1 ng/g dry weight), and methylparathion (<
0.2-16.8 ng/g dry weight) were also detected. Total PCB concentrations observed in sediments ranged from 68 to 763 ng/g
dry wt. Total average PCB concentrations were significantly (p
0.004) higher for sediments from the downstream sampling
sites compared to the upstream samples. Tetra- and trichlorobiphenyls accounted for 84 and 88% of the total residues measured
in the downstream and tributary locations, respectively. In contrast, heptachlorobiphenyls were the prevailing homologues in
sediments from the upstream sampling site, contributing 51%
of the total PCB concentration. Predominant PCB homologues
were: trichlorobiphenyl congener 28 and 37, tetrachlorobiphenyl
congeners 44, 49, 52, 74, 77, and 81, and heptachlorobiphenyl
congener 170. Sediment concentrations of DDE (19.7 ng/g dry
weight) in the tributary, heptachlor epoxide (3.0 ng/g dry weight)
in the downstream, and nickel (128-170 g/g dry weight) in all
locations exceeded Probable Effect Levels (PELs) established for
sediment quality in fresh water, indicating probable environmental stress and the potential for adverse effects to benthic organisms
in the Dniester River. В© 2005 Springer Science+Business Media,
Inc.
1673 Impact of highly basic solutions on sorption of Cs+ to
subsurface sediments from the Hanford site, USA
Ainsworth C.C., Zachara J.M., Wagnon K. et al. Geochimica et
Cosmochimica Acta 2005 69/20 (4787-4800)
The effect of caustic NaNO3 solutions on the sorption of 137 Cs to
a Hanford site micaceous subsurface sediment was investigated
as a function of base exposure time (up to 168 d), temperature (10В°C or 50В°C), and NaOH concentration (0.1 mol/L to 3
mol/L). At 10В°C and 0.1 M NaOH, the slow evolution of [Al]aq
was in stark contrast to the rapid increase and subsequent loss
of [Al]aq observed at 50В°C (regardless of base concentration).
Exposure to 0.1 M NaOH at 10В°C for up to 168 d exhibited
little if any measurable effect on sediment mineralogy, Cs+ sorption, or Cs+ selectivity; sorption was well described with a twosite ion exchange model modified to include enthalpy effects.
At 50В°C, dissolution of phyllosilicate minerals increased with
[OH]. A zeolite (tetranatrolite; Na2 Al2 Si3 O10 2H2 O) precipitated in 0.1 M NaOH after about 7 days, while an unnamed
mineral phase (Na14 Al12 Si13 O51 6H2 O) precipitated after 4 and
2 days of exposure to 1 M and 3 M NaOH solutions, respectively.
Short-term (16 h) Cs+ sorption isotherms (10-9 -10-2 mol/ L) were
measured on sediment after exposure to 0.1 M NaOH for 56,
112, and 168 days at 50В°C. There was a trend toward slightly
lower conditional equilibrium exchange constants ( log Na Cs Kc
0.25) over the entire range of surface coverage, and a slight loss
of high affinity sites (15%) after 168 days of pretreatment with
0.1 M base solution. Cs+ sorption to sediment over longer times
was also measured at 50В°C in the presence of NaOH (0.1 M, 1 M,
and 3 M NaOH) at Cs+ concentrations selected to probe a range
of adsorption densities. Model simulations of Cs+ sorption to the
sediment in the presence of 0.1 M NaOH for 112 days slightly
under-predicted sorption at the lower Cs+ adsorption densities.
At the higher adsorption densities, model simulations under-predicted sorption by 57%. This under-prediction was surmised to
be the result of tetranatrolite precipitation, and subsequent slow
Na ! Cs exchange. At higher OH concentrations, Cs+ sorption
in the presence of base for 112 days was unexpectedly equal to,
or greater than that expected for pristine sediment. The precipi-
SEDIMENTOLOGY
tation of secondary phases, coupled with the fairly unique mica
distribution and quantity across all size-fractions in the Hanford
sediment, appears to mitigate the impact of base dissolution on
Cs+ sorption. Copyright В© 2005 Elsevier Ltd.
1674 Trace metal distribution and enrichment in benthic,
estuarine sediments: Southport Broadwater, Australia
Burton E.D., Phillips I.R. and Hawker D.W. Environmental
Geochemistry and Health 2005 27/5-6 (369-383)
The distribution and enrichment of selected trace metals (Cd,
Cr, Cu, Ni, Pb, Sn, Zn) in benthic sediments of the Southport
Broadwater, a semi-enclosed coastal body of water adjacent to
the Gold Coast city, south-eastern Queensland, Australia, was
studied with the objective of assessing the extent and degree of
sediment contamination. Sediment samples from the 0-10 cm
and 10-20 cm depth intervals of 32 sites within the Southport
Broadwater and surrounding residential canals were analysed for
particle size distribution, pH, organic C and вЂ�near-totalвЂ™ major
(Al, Ca, Fe, Mn) and trace (Cd, Cr, Cu, Ni, Pb, Sn, Zn) metal contents. Sediment contamination for each trace metal was assessed
by (1) comparison with Australian sediment quality guidelines,
(2) calculation of the index of geoaccumulation based on regional
background values, and (3) geochemical normalisation against Al
(i.e. the abundance of alumino-silicate clay minerals). Based on
this approach, the results indicate that submerged sediments in the
study area are not presently enriched with Cd, Cr or Ni, with the
spatial distribution of these metals being very well explained by
the abundance of alumino-silicate clay minerals. However, several sites were strongly enriched with Cu, Pb, Sn and Zn, arising
from sources related to either urban runoff or vessel maintenance
activities. The study indicates that several varying approaches are
needed for a satisfactory assessment of contaminant enrichment
in estuarine sediments. В© Springer 2005.
1675 Seasonal variations of racte metal chemical forms in
bed sediments of a karstic river in Lebanon: Implications for
self-purification
Korfali S.I. and Davies B.E. Environmental Geochemistry and
Health 2005 27/5-6 (385-395)
Although Lebanon has abundant water, its rivers are polluted
and aquifer water mismanaged. Effective river water usage requires an understanding of the geochemistry of polluting metals
in catchments. Climate is "Mediterranean": Wet winters and dry
summers. Active sediment flushing is restricted to winter high
discharge episodes. Except in winter, water column pollutants
are removed by precipitation or sorption to the surface of static
bed sediments. Hence (1) does winter flushing of contaminated
sediment and replacement by clean sediment favour self purification? (2) does the distribution of metals between extractable
fractions change seasonally and thereby affect metal bioavailability? Results on the distribution of metals are reported for
Fe, Pb, Zn, Cu and Cd in bed sediments from Nahr Ibrahim (a
karstic river) for summer and winter. A Tessier-like sequential
extraction scheme was applied to samples (< 75 m) for five locations along a 13 km stretch to the sea. Water pH was above 8.2
at all locations implying a very low solubility for Fe. Sediment
was derived from catchment soils and limestone. Total sediment
Fe increased in winter at all sites following deposition of eroded
soil from upstream. Cadmium, Cu and Pb derived from polluting
sources; the sources of Zn were more complex. Dilution by clean
sediment explained winter reductions in total Cd, Cu and Pb; Zn
changes were less consistent. Iron occurred mostly (> 77% sum
of fractions) in the residual fraction compared with 6-31% for
pollutants; residual Cu and Zn showed a small increase in winter
whereas Cd and Pb did not change. All readily exchangeable
metals decreased in winter and the carbonate bound forms predominated in both seasons. Nahr Ibrahim has a high capacity for
self purification and metal resolubilisation from sediment will be
limited by the solubility of carbonate forms. В© Springer 2005.
1676 Geochemical distribution and bioavailability of heavy
metals and oxalate in street sediments from Rio de Janeiro,
Brazil: A preliminary investigation
McAlister J.J., Smith B.J., Neto J.B. and Simpson J.K. Environmental Geochemistry and Health 2005 27/5-6 (429-441)
As urbanisation accelerates within less-economically developed
countries, populations in cities such as Rio de Janeiro are sub-
319
ject to numerous health risks relating to "heavy metal", sewage
and vehicle pollution. These risks apply especially to children,
through inhalation and dermal contact with pollutant-rich street
sediments that reflect contamination from atmospheric deposition and act as effective sinks for heavy metals and oxalates.
To assess the nature and extent of these risks street sediments
were collected from industrial, commercial, residential and recreational areas with varying traffic densities within Rio de Janeiro.
A modified selective extraction procedure was used to study the
geochemical partitioning and bioavailability of Fe, Mn, Zn, Cu,
Cr, Ni, Pb and C2 O-4 . Oxalate partitioning has not been studied
by traditional sequential methods and results from this procedure
highlight the potential bioavailability of both oxalates and "heavy
metals", especially Pb and C2 O-4 in industrial and recreational
areas. В© Springer 2005.
1677 Transformation of arsenic compounds in modern intertidal sediments of Iriomote Island, Japan
Masuda H., Yamatani Y. and Okai M. Journal of Geochemical
Exploration 2005 87/2 (73-81)
The arsenic accumulation process in intertidal sediments of Iriomote Island, Japan, is analyzed as a naturally balanced arsenicfixation system. Major and minor element chemistry is analyzed
by X-ray fluorescence photometry, mineralogy is investigated by
X-ray diffractometry, and four arsenic compounds are characterized by hydrogen-generated atomic absorption photometry. It
is found that arsenic is accumulated by iron hydroxides/oxides
precipitated following the decomposition of humic acids in the
shallower sediment, and is subsequently incorporated into iron
sulfide minerals at depth. The arsenic is immobile during incorporation into arsenic-bearing phases, suggesting that arsenic is
unlikely to be released into the porewater under natural conditions
in early diagenesis. The formation and decomposition of arsenicbearing organic compounds appear to be associated with the formation and decomposition of arsenic in oxyhydroxides/oxides,
suggesting that microbial activity may play an important role in
controlling the behavior of arsenic and arsenic-bearing phases in
the sediment column. В© 2005 Elsevier B.V. All rights reserved.
1678 Preliminary magnetic studies of lagoon and stream
Вґ Area (Argentina) - Magnetic pasediments from Chascomus
rameters as indicators of heavy metal pollution and some
results of using an experimental method to separate magnetic
phases
Chaparro M.A.E., Lirio J.M., NuЛњnez H. et al. Environmental
Geology 2005 49/1 (30-43)
Magnetic properties of lagoon and stream sediments from
ChascomВґus area (Buenos Aires Province) and the relevance of
various magnetic parameters as giving pollution status are studied
in the present work. This work is focussed on magnetic parameters, such as concentration-dependent (magnetic susceptibility,
saturation anhysteric and isothermal remanent magnetisation)
and feature-dependent parameters (S-ratio, coercivity of remanence, anhysteric susceptibility/magnetic susceptibility-ratio), as
pollution indicators. Firstly and most importantly, different magnetic parameters and chemical measurements were correlated in
order to investigate their goodness, obtaining the best results
for feature-dependent magnetic parameters. Coercivity of remanence correlate very well with chemical variables, showing
correlations at high level of significance up to 0.9094, and the
anhysteric susceptibility/magnetic susceptibility-ratio also shows
very good correlations (up to 0.8376). Some results and advantages of using a new experimental method in order to discriminate
hard and soft magnetic phases are also shown. This method uses
alternately backfield isothermal remanent magnetisation and alternating field demagnetisation. From the experimental separation, the presence of hard magnetic phases in some samples was
confirmed. В© Springer-Verlag 2005.
1679 The influence of fly and bottom ash deposition on the
quality of Kastela Bay sediments
Orescanin V., Barisic D., Lovrencic I. et al. Environmental Geology 2005 49/1 (53-64)
The objective of this study was chemical and radiological characterization of Kastela Bay sediments exposed to numerous anthropogenic sources like deposition of fly and bottom ash enriched
320
SOILS
in radionuclides and heavy metals, chemical plant, cement plant,
iron plant, shipyard, electroplating facility, untreated industrial
and domestic waste waters as well as heavy traffic. Totally, 33
samples of the mixture of fly and bottom ash, 12 sediment cores
ranging from 0 to 40 cm and nine surface sediment samples were
analyzed. Enrichment in heavy metals in the mixture of fly and
bottom ash was ranging from 1.5 to 36 times compared to flysch
soil while 226 Ra and 238 U were up to 50 times enriched compared
to average activities characteristic for surrounding soils developed on the Middle and Upper Eocene flysch. Maximum 238 U
activity was approximately 32 times higher and 226 Ra approximately 40 times higher in the Kastela Bay sediment compared
to mean value determined for Adriatic sediments. The highest
enrichment in sediment cores compared to background values
were found for Zn (35.6 times), Pb (16 times), Cr (9.1 times) and
Ni (4 times) В© Springer-Verlag 2005.
(GSUE) project was initiated in 1992 and to date, 21 cities have
been mapped. Urban sampling is based upon the collection of
top (0.05 to 0.20 m) and deeper (0.35 to 0.50 m) soil samples on
a 500 m grid across the built environment (one sample per 0.25
km2 ). Samples are analysed for c. 46 total element concentrations by X-ray fluorescence spectrometry, pH and loss on ignition
as an indicator of organic matter content. The data provide an
overview of the urban geochemical signature and because they
are collected as part of a national baseline programme, can be
readily compared with soils in the rural hinterland to assess the
extent of urban contamination. The data are of direct relevance
to current UK land use planning, urban regeneration and contaminated land legislative regimes. An overview of the project
and applications of the data to human health risk assessment,
water quality protection and contaminant source identification
are presented. В© 2005 AAG/ Geological Society of London.
1680 Impact of human activity on the estuary of the Qiantang River and the reclamation of tidal flats and river
regulation
Feng L.- H. and Bao Y.- X. Environmental Geology 2005 49/1
(76-81)
The swing of the main channel of the Qiantang River is controlled by the high-water and low-water changes in the river, as
well as the impact of large-scale reclamation of tidal flats. Its
evolution in modern times is the result of the combined functions
of natural and man-made factors. This paper analyzes the cause
of the formation of the South Channel and Xisan Tidal Furrow
and proposes the regulation principle of "To regulate the river and
reclaim tidal flats by taking the advantage of local topography".
It is suggested to cut off the South Channel and Xisan Tidal
Furrow completely to restrict the swing of the main channel and
to increase the reclamation area of the tidal flat at the same time.
В© Springer-Verlag 2005.
1683 G-BASE: Baseline geochemical mapping of Great Britain and Northern Ireland
Johnson C.C., Breward N., Ander E.L. and Ault L. Geochemistry:
Exploration, Environment, Analysis 2005 5/4 (347-357)
The Geochemical Baseline Survey of the Environment is a
longestablished, high-resolution regional geochemical mapping
project run by the British Geological Survey. A project initially stimulated by mineral exploration and to assist geological
mapping has successfully evolved into a survey that has many
environmental applications. Much of the current demand for surface geochemical data is driven by legislation. The geochemical
mapping, originally based on the collection of drainage samples,
has expanded to include soils and a further suite of determinands
in stream waters. The methodology of the project and application of the baseline data are described and issues common to
worldwide geochemical mapping programmes are discussed. В©
2005 AAG/ Geological Society of London.
SOILS
Regional and survey
1681 Sub-continental-scale geochemical mapping: Sampling, quality control and data analysis issues
Reimann C. Geochemistry: Exploration, Environment, Analysis
2005 5/4 (311-323)
During 1996/97, c. 1500 samples of agricultural soils from ten
northern European countries (western Belarus, Estonia, Finland,
northern Germany, Latvia, Lithuania, Norway, Poland, northwestern Russia and Sweden) were collected from the Ap and
B/C-horizons at 750 sites. The sample sites were evenly spread
over a 1 800 000 km2 area, giving an average sample density of
one site per 2500 km2 . The <2 mm fractions (Poland: <1 mm)
of all samples were analysed for up to 62 chemical elements
following ammonium acetate, aqua regia and HF extractions,
and for total element concentrations by X-ray fluorescence spectrometry. Electrical conductivity, pH (water extraction) and loss
on ignition (1030В°C) were also determined. Each method was
applied to all the samples in one laboratory only. The analytical
results were evaluated and mapped using exploratory data analysis techniques. Even at this low sample density, regional-scale
geochemical patterns emerge for all elements. These patterns
show the influence of factors such as geology, agriculture, pollution, topography, marine aerosols and climate, and their relative
importance for the observed element concentrations in the soils.
Low-density geochemical mapping of agricultural soils is a viable tool to study the geochemical processes that determine the
element distribution in soils at a sub-continental scale. В© 2005
AAG/ Geological Society of London.
1682 GSUE: Urban geochemical mapping in Great Britain
Fordyce F.M., Brown S.E., Ander E.L. et al. Geochemistry:
Exploration, Environment, Analysis 2005 5/4 (325-336)
The British Geological Survey is responsible for the national
strategic geochemical survey of Great Britain. As part of this
programme, the Geochemical Surveys of Urban Environments
1684 Geochemical mapping at the Geological Survey of
Sweden
Lax K. and Selinus O. Geochemistry: Exploration, Environment,
Analysis 2005 5/4 (337-346)
Geochemical mapping has been carried out for several decades at
the Geological Survey of Sweden (SGU). Two kinds of sampling
media dominate: glacial till (soil geochemical programme) and
aquatic vegetation (biogeochemical mapping). Data from these
mapping programmes have been used for various applications
such as discoveries of contaminated land and research in environmental, medical and mineral exploration. The main goal
of the geochemical mapping programmes has been to produce
consistent and high quality data. Therefore, both programmes
have been subject to various changes to increase their usefulness
for decision-makers and planners. The number of parameters
determined has increased, partial leach analysis has migrated
from a combination of AAS/ ICP-AES techniques to ICP-MS,
urban geochemistry projects have been incorporated, and additional terrestrial sediments have been added to the regional soil
geochemical survey. An increasing number of new applications
have also been implemented for emerging societal needs. This
paper gives an overview of the mapping programme and examples of products for use in society as well as strategies for the
future. В© 2005 AAG/ Geological Society of London.
1685 Dynamic changes of soil ecological factors in Ziwuling
secondary forest area under human disturbance (Chinese)
Zhou Z. and Shangguan Z. Chinese Journal of Applied Ecology
2005 16/9 (1586-1590)
As a widespread natural phenomenon, disturbance is considered
as a discrete event occurred in natural ecosystems at various
spatial and temporal scales. The occurrence of disturbance directly affects the structure, function and dynamics of ecosystems.
Forest logging and forestland assart, the common human disturbances in forest area, have caused the dynamic changes of forest
soil ecological factors in a relatively consistent environment. A
study on the dynamics of soil bulk density, soil organic matter,
soil microbes and other soil ecological factors under different human disturbance (logging and assart, logging but without assart,
control) were conducted in the Ziwuling secondary forest area.
The results indicated that human disturbance had a deep impact
on the soil ecological factors, with soil physical and chemical
SOILS
properties become bad, soil organic matter decreased from 2.2%
to 0.8%, and soil stable aggregates dropped more than 30%. The
quantity of soil microbes decreased sharply with enhanced human
disturbance. Soil organic matter and soil microbes decreased
more than 50% and 90%, respectively, and soil bulk density
increased from 0.9 to 1.21 g cm-3 with increasing soil depth.
Ditch edge level also affected the dynamics of soil factors under
the same disturbance, with a better soil ecological condition at
low-than at high ditch edge level.
Methods
1686 Development and evaluation of a simplified mechanistic-stochastic method for field-scale solute transport
prediction
Lee J. and Casey F.X.M. Soil Science 2005 170/4 (225-234)
Field-scale solute transport is extremely complex due to the variability of soil properties. In this paper, a mechanistic-stochastic
procedure for predicting field-scale solute transport was developed and evaluated. The mechanistic-stochastic method was
based on a stream-tube model, which makes predictions using
field estimates of shallow soil mobile water contents ( m ) determined with a multiport permeameter. This procedure was
evaluated for its ability to predict solute transport in a field soil.
A field leaching experiment was conducted using fluorinated
benzoic acid tracers that were applied to the surface at 12 plots
in a field under pivot irrigation. Soil cores were taken to 1.5m depth at 1, 8, 18, and 36 days after initial tracer application
to determine tracer redistribution. The mechanistic- stochastic
method was compared with the observed data and against another
stochastic method, a transfer function model (TFM), to evaluate
its ability to predict solute redistribution for each sampling date.
The proposed method had satisfactory predictions of the mean
solute concentration redistributions from the leaching experiment
and compared well against the predictions made by the TFM.
The coefficients of determination ranged from 0.57 to 0.92 for
the mechanistic-stochastic method and 0.29 to 0.99 for the TFM.
The mechanistic-stochastic method can be greatly simplified,
making it practical and desirable over the TFM, which required
extensive subsoil leaching data for its calibration. Copyright В©
2005 by Lippincott Williams & Wilkins, Inc.
1687 Influence of soil moisture on near-infrared reflectance
spectroscopic measurement of soil properties
Chang C.- W., Laird D.A. and Hurburgh Jr. C.R. Soil Science
2005 170/4 (244-255)
Near-infrared reflectance spectroscopy (NIRS), a nondestructive
analytical technique, may someday be used to rapidly and simultaneously quantify several soil properties in agricultural fields.
The objectives of this study were to examine the influence of
moisture content on the accuracy of NIRS analysis of soil properties and to assess the robustness of a NIRS multivariate calibration technique. Four hundred agricultural soil samples (<2 mm)
from Iowa and Minnesota were studied at two moisture levels:
moist and air-dried. The soil properties tested included total C,
organic C, inorganic C, total N, CEC, pH, texture, moisture, and
potentially mineralizable N. About 70% of the Iowa samples were
selected for the calibration set, and the rest of the Iowa samples
and all of the Minnesota samples were assigned to validation set
I and validation set II, respectively. Calibrations were based on
partial least-squares regression (PLSR), using the first differentials of log (1/R) for the 1100 to 2500-nm spectral range. The
results for the calibration set and validation set I indicated that
NIRS-PLSR was able to predict many soil properties (total C,
organic C, inorganic C, total N, CEC, % clay, and moisture) with
reasonable accuracy for both the air-dried (R2 > 0.76) and moist
(R2 > 0.74) soils. The results for validation set II showed that
NIRS-PLSR was able to predict some properties of soils (total
C, organic C, total N, and moisture content) from a different geographic region, but other soil properties in validation set II were
not accurately predicted. Although NIRS-PLSR predictions are
slightly more accurate for air-dried soils than for moist soils, the
results indicate that the NIRS-PLSR technique can be used for
analysis of field moist samples with acceptable accuracy as long
as diverse soil samples from the same region are included in the
321
calibration database. Copyright В© 2005 by Lippincott Williams
& Wilkins, Inc.
1688 A new in situ method to analyze mineral particle reactions in soils
Birkefeld A., Schulin R. and Nowack B. Environmental Science
and Technology 2005 39/9 (3302-3307)
We developed a simple method to monitorthe transformation of
particles in soils under in situ conditions. The particles were
fixed on small polymer supports (2 cm x 2 cm) with a thin film of
epoxy resin. Attached to these carriers, the particles could be put
into close contact with soil at a chosen site and easily recovered
after extended periods of time. The method was tested with lead
oxide and copper concentrate in the field. Quartz and copper
oxide particles were used in preliminary laboratory experiments.
The used particles sizes ranged from 20 to 200 m. Laboratory
and field experiments with acidic and calcareous soils showed
that the PbO and Cu concentrate coated polymer supports were
stable under field conditions for at least one year. Nondestructive X-ray fluorescence spectroscopy was used to quantify the
metals before and after exposure. Scanning electron microscopy
combined with energy-dispersive X-ray spectroscopy as well as
micro-Raman spectroscopy was used to identify signs of dissolution and newly formed mineral phases. The mineral dissolution
rate could be determined under field conditions. The new method
has the potential to be used in other environmental media such as
sediments or water to study the reactions of a variety of particles
larger than 20 m. В© 2005 American Chemical Society.
1689 Soil water estimation using electromagnetic induction
Akbar M.A., Kenimer A.L., Searcy S.W. and Torbert H.A. Transactions of the American Society of Agricultural Engineers 2005
48/1 (129-135)
Two published salinity models (designated the Rhoades and
Mualem-Friedman models, respectively) were examined for application to real-time soil water estimation using apparent soil
electrical conductivity. Field data were collected at two sites
representing a range of soil types in central Texas: high shrinking-swelling Vertisols in Temple (the Heiden Clay site) and clay
loam soils at the Texas A&M University Research Farm near
College Station (the Westwood Scl site). The Rhoades-Corwin
model developed for the Heiden Clay site yielded an R2 of 0.72
following calibration, predicted soil water within 0.02 g g-1 during validation, and was deemed generally applicable for real-time
soil water estimation. The Rhoades-Corwin model developed for
the Westwood Scl site gave an R2 of 0.65 following calibration
but could not be validated at the site and therefore was not considered applicable for real-time soil water estimation. A modified
version of the Rhoades-Corwin model yielded a calibrated R2 of
0.91 at the Westwood Scl site with validation predictions within
0.02 g g -1 . The Mualem-Friedman model predicted soil water
within 0.05 g g-1 at the Heiden Clay site and was considered
appropriate for real-time soil water estimation. At the Westwood
Scl site, the Mualem-Friedman model could not be evaluated
since saturation data were not available. Both models show
promise for use for real-time, non-invasive soil water content
estimation using apparent electrical conductivity, but additional
testing is needed.
1690 Comparison of three extraction methods for 17 -estradiol in sand, bentonite, and organic-rich silt loam
Chun S., Lee J., Geyer R. and White D.C. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants,
and Agricultural Wastes 2005 40/5 (731-740)
Extraction is an important procedure for samples that contain soil
because other compounds in soil may affect analysis of estrogens.
This study was conducted to evaluate three different extraction
methods for 17 -estradiol in soil. Sand, bentonite, and organicrich silt loam were spiked with 1 mg kg-1 of 17 -estradiol as a
model compound of estrogens. 17 -estradiol and its metabolites,
estrone and estriol, were extracted using (i) a modified Bligh and
Dyer extraction, (ii) a pressurized fluid extraction, and (iii) a
diethyl ether extraction, and measured by liquid chromatography
tandem mass spectrometry. There were significant differences in
the extraction efficiency for 17 -estradiol among the extraction
methods and the soils: the efficiencies ranged from 10% to 97%.
322
SOILS
Overall, the diethyl ether extraction method had the largest efficiency of 17 -estradiol with 45% and 57% for bentonite and
silt loam, respectively. Transformation of 17 -estradiol to estrone and estriol in the different extraction methods was less than
3.6% during the extraction procedures. This study underlined
the importance of sample preparation for estrogen analysis in
soil samples. Copyright В© Taylor & Francis Inc.
1691 Effect of agricultural antibiotics on the persistence and
transformation of 17 -estradiol in a Sequatchie loam
Chun S., Lee J., Geyer R. et al. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and
Agricultural Wastes 2005 40/5 (741-751)
A laboratory incubation study was conducted to investigate the
effect of agricultural antibiotics (sulfamethazine, tylosin, and
chlortetracycline) on the persistence and transformation of 17 estradiol in Sequatchie loam. We measured concentrations
of 17 -estradiol and its primary metabolite (estrone) in soils
spiked with antibiotics and 17 -estradiol. Dehydrogenase activity (DHA) was also measured as an indicator of the total microbial
activity of the soils. The presence of antibiotics significantly decreased transformation of 17 -estradiol to estrone. There was
a positive correlation between the DHA and the concentrations
of estrone in soil spiked with 17 -estradiol only, implying that
the reaction is mainly catalyzed by dehydrogenases. However,
the positive correlation was weakened in soil spiked with 17 estradiol and antibiotics together. We recommend that any study
evaluating the fate and transport of estrogenic hormones in soil
should include the effect of agricultural antibiotics because antibiotics and estrogenic hormones are commonly excreted together
in environmental samples. Copyright В© Taylor & Francis Inc.
1692 Soil identification and chemometrics for direct determination of nitrate in soils using FTIR-ATR mid-infrared
spectroscopy
Linker R., Shmulevich I., Kenny A. and Shaviv A. Chemosphere
2005 61/5 (652-658)
The use of mid-infrared attenuated total reflectance (ATR) spectroscopy enables direct measurement of nitrate concentration in
soil pastes, but strong interfering absorbance bands due to water and soil constituents limit the accuracy of straightforward
determination. Accurate subtraction of the water spectrum improves the correlation between nitrate concentration and its 3
vibration band around 1350 cm-1 . However, this correlation
is soil-dependent, due mostly to varying contents of carbonate,
whose absorbance band overlaps the nitrate band. In the present
work, a two-stage method is developed: First, the soil type is
identified by comparing the "fingerprint" region of the spectrum
(800-1200 cm-1 ) to a reference spectral library. In the second
stage, nitrate concentration is estimated using the spectrum interval that includes the nitrate band, together with the soil type
previously identified. Three methods are compared for estimating nitrate concentration: integration of the nitrate absorbance
band, cross-correlation with a reference spectrum, and principal
component analysis (PCA) followed by a neural network. When
using simple band integration, the use of soil specific calibration curves leads to determination errors ranging from 5.5 to 24
mg[N]/kg[dry soil] for the mineral soils tested. The cross-correlation technique leads to similar results. The combination of soil
identification with PCA and neural network modeling improves
the predictions, especially for soils containing calcium carbonate. Typical prediction errors for light non-calcareous soils are
about 4 mg[N]/kg[dry soil], whereas for soils containing calcium
carbonate they range from 6 to 20 mg[N]/kg[dry soil], which is
less than four percent of the concentration range investigated. В©
2005 Elsevier Ltd. All rights reserved.
1693 Modification and application of a soil ATP determination method
Wen G., Voroney R.P., Curtin D. et al. Soil Biology and Biochemistry 2005 37/11 (1999-2006)
Accurate estimation of microbial adenosine 5 -triphosphate
(ATP) is a pre-requisite to quantify the impact of varying environments on microbial activity of soil. We investigated the
effectiveness of a high efficiency soil ATP determination method
(PA) [Webster, J.J., Hampton, G.J., Leach, F.R., 1984. ATP in
soil: a new extractant and extraction procedure. Soil Biology &
Biochemistry 4, 335-342] in 10 Ontario (Canada) soils collected
along a 100 m transect and spanning a textural class gradient
ranging from a sandy loam to clay loam with increasing organic
matter. Modifications of the method involved using an extract of
autoclaved soil to make the standard curve, as it was found that
the light emitted by ATP luciferin-luciferase bioluminescence
reaction in the pure extractant was different from that in the
extracts. Replacing Tricine with Tris buffer in the assay significantly improved the light emission. On an average, the internal
standard calibration method (ISM) measured a smaller amount of
extracted ATP (1199 ng ATP g-1 soil) and a lower recovery of ATP
spike (82.4 7.2%) than did the standard curve method (SCM)
(1246 ng ATP g-1 soil and 91.2 4.5%, respectively) (P<0.05 for
both comparisons). However, the average total estimated ATP
was higher with ISM (1474 102 ng ATP g-1 soil) than with SCM
(1373 88 ng ATP g-1 soil) (P<0.07). While the recovery rates
determined using SCM were consistent among the soils tested,
the rates measured using ISM was negatively correlated with soil
clay and organic matter content, implying that the latter assay
was affected by the soil properties. Our results confirmed that
the recovery rates obtained by the PA method were the highest among those reported, when only SCM was used. В© 2005
Elsevier Ltd. All rights reserved.
1694 Nematodes as bioindicator of soil health: Methods and
applications (Chinese)
Li Y., Wu J., Chen H. and Chen J. Chinese Journal of Applied
Ecology 2005 16/8 (1541-1546)
This paper summarized the advantages of using nematodes as
soil health bioindicator. A review of commonly used indices and
analyzing methods by means of nematodes was presented, with
emphases on Maturity Index, as well as the indices and analyzing methods based on their trophic groups. Compared with other
indices, Maturity Index can reflect the stressed degree of soil
more sensitively, and the indices and analyzing methods based
on their trophic groups can well reveal the state of soil health
based on ecosystem functioning. The applications of nematodes
as bioindicator in agriculture, forest, grassland, and other ecosystems were also outlined. In view of some practical limitations
in the methods, prospective researches and applications were
suggested, i.e., intensify the ecological studies to advance the
understanding on the characteristics of soil nematodes, such as
their life histories and feeding habits, consummate the indication
system by integrating various nematode indices and analyzing
methods, and extend the applications of soil nematodes in different ecosystems and in different regions at large scales.
Genesis and formation
1695 The role of fire and nutrient loss in the genesis of the
forest soils of Tasmania and southern New Zealand
McIntosh P.D., Laffan M.D. and Hewitt A.E. Forest Ecology and
Management 2005 220/1-3 (185-215)
The dominant soil patterns in forested or previously forested
landscapes in southern New Zealand and Tasmania are described.
Soil properties on adjacent sunny and shady aspects in hill country of the South Island of New Zealand are compared to soil properties under adjacent вЂ�dryвЂ™ and вЂ�wetвЂ™ eucalypt forest in Tasmania.
A soil contrast index or SCI is defined for comparing soil contrasts on parent materials of different absolute nutrient contents.
Three soil groups are defined using the SCI. Group 1 soil pairs
are stable New Zealand soils in which exchangeable Ca + Mg +
K values are higher on drier sunny aspects than on moister shady
aspects. Group 2 soil pairs are New Zealand soils in which soils
on sunny aspects display evidence of topsoil erosion by wind;
consequently some soil pairs on dry (sunny) aspects have lower
levels of exchangeable Ca + Mg + K than soils on moister (shady)
aspects. Group 3 soil pairs are Tasmanian. Soils on drier sites
(under dry eucalypt forest) invariably have lower exchangeable
Ca + Mg + K values than soils on moister sites (under wet eucalypt
forest), which is the reverse of the pattern in SCI Group 1 soils in
New Zealand. Except on clay-rich parent materials, Tasmanian
soils under dry forest generally have texture-contrast profiles and
a mean C/N ratio in topsoils (A1 horizons) of 29. Soils under
SOILS
wet forest generally have uniform or gradational texture profiles
and a mean topsoil C/N ratio of 15. The texture-contrast soils
show strong clay eluviation with sand or sandy loam textures in
upper horizons and clayey textures in lower horizons. However,
in New Zealand texture-contrast soils are all but absent, and do
not occur in the previously forested areas described in this paper.
Topsoils (Ah horizons and soils sampled to 7.5 cm depth) in New
Zealand areas sampled in this study have a mean C/N ratio of 15,
regardless of whether they occur on sunny or shady aspects. We
propose that the frequency and spatial occurrence of fire are the
dominant processes causing: (1) the marked difference in levels
of nutrients and different topsoil C/N ratios in soils of Tasmania;
(2) the development of texture-contrast soils under dry forests in
Tasmania; and (3) the difference between soil patterns in New
Zealand and Tasmania. Fire depletes nutrients in forests by
causing losses to the atmosphere, losses by runoff, and losses by
leaching. Nutrient loss by fire encourages fire-tolerant vegetation
adapted to lower soil nutrient status, so frequent fire is a feedback
mechanism that causes progressive soil nutrient depletion. By
destroying organic matter and diminishing organic matter supply
to the soil surface fire inhibits clay-organic matter linkages and
soil faunal mixing and promotes clay eluviation. Fire frequency
is likely to have increased markedly with the arrival of humans at
ca. 34 000 years B.P. in Tasmania and ca. 800 years B.P. in New
Zealand. We argue that texture-contrast soils have not formed in
New Zealand because of the short history of frequent fires in that
country. A corollary of this conclusion is that texture-contrast
soils in Tasmania are, at least in part, anthropogenic in origin. В©
2005 Elsevier B.V. All rights reserved.
1696 Soils developed on volcanic materials in the island of
Thera, Greece
Moustakas N.K. and Georgoulias F. Geoderma 2005 129/3-4
(125-138)
Samples were taken of soils formed on volcanic material, primarily composed of rhyodacitic pumice, on the island of Thera,
Greece (South Aegean Sea, Southeastern Mediterranean), and
analyses for physical and chemical properties carried out. These
soils are characterised as having a coarse texture, low organic
matter content, low cation exchange capacity (CEC) and soil
moisture retention, but a high pH despite the acidic nature of
the parent material. Extraction with sodium dithionite-citrate,
acid ammonium oxalate, sodium pyrophosphate and hot 0.5 M
NaOH showed that, in contrast to soils usually forming on volcanic material worldwide, soils lack noncrystalline minerals like
allophane, imogolite, ferrihydrite and iron and aluminium humus
complexes. The only noncrystalline mineral present and, in great
quantities, is amorphous silica. Winds, prevailing practically all
year round, transfer droplets of seawater to these soils which
in combination with the great porosity, relatively high sodium
content of the parent material and low rainfall are the primary
factors in the poor development of these soils and high pH. No
andic properties are apparent and, hence, these soils cannot be
classified as Andisols. The major factors determining soil genesis on the island of Thera would appear to be the nature of the
parent material and the climate. В© 2004 Elsevier B.V. All rights
reserved.
1697 Exploring pedogenesis via nuclide-based soil production rates and OSL-based bioturbation rates
Wilkinson M.T. and Humphreys G.S. Australian Journal of Soil
Research 2005 43/6 (767-779)
New dating techniques are available for soil scientists to test fundamental pedogenic ideas. Recent developments in applications
of terrestrial in situ cosmogenic nuclides (TCN) from bedrock
and saprolite allow the derivation of soil production rates, at
scales ranging from local (sub-hillslope) to catchment wide,
generally averaged over timescales of 104 -105 years. Where
soil depths are relatively constant over time, soil production rates
equal transport rates and are thus essential to establishing sustainable erosion rates. TCN also allow the form of the soil production
function to be compared to theoretical models - a difficult task
previously. Furthermore, parameterised soil production functions can now be incorporated into numerical surface process
models to test landscape evolution ideas. Bedrock and saprolite conversion to soil is demonstrably dependent on the overlying soil depth, and there is general agreement that weathering
323
declines exponentially beyond maximum soil production, consistent with theory. Whether maximum soil production occurs
under a finite or non-existent soil cover at particular sites remains
unresolved. We suggest that, in general, soil production from saprolite declines exponentially with increasing depth, while production from bedrock follows a humped function. Estimates of
the role of flora, fauna and processes such as freeze-thaw that
mix soil mantles to depth, have been limited prior to optically
stimulated luminescence (OSL) dating techniques. Recently derived OSL mixing rates extend the magnitude of previous partial,
short-term bioturbation rates. In fact, bioturbation appears to be
the most active pedogenic process operating in many soils, with
freeze-thaw environments a noted exception. Although bioturbation far outweighs soil production, it does not always lead to
homogenisation as is often reported. We maintain that the aboveground component of bioturbation, i.e. mounding, may alone,
or particularly when combined with particle sorting via rainwash
processes, lead to horizonisation and texture contrast soils in
those materials that can be sorted such as mixtures of sand and
clay. Together, TCN- and OSL-based estimates of hillslope soil
transport and bioturbation, suggest significant rates of downslope
soil mantle movement coupled with rapid mixing, contrary to in
situ soil development models. В© CSIRO 2005.
1698 Formation and properties of aridic soils of Azraq Basin
in northeastern Jordan
Khresat S.A. and Qudah E.A. Journal of Arid Environments 2006
64/1 (116-136)
Aridisols occupy a wide and significant part of Jordan. The
majority of soils in the Azraq Basin, northeastern Jordan, are
aridisols. A database on aridisols and land characteristics in
northeastern Jordan is needed to allow rational planning of land
and water resources utilization. The objectives of this paper are
to: characterize the main soil types in the area, and identify the
main processes contributing to their genesis and evolution. For
this purpose eight representative profiles were selected for this
study and soil samples were collected and their chemical and
physical properties were examined in the laboratory. The natural
vegetation is desert shrubs and short grasses. The sparseness
of the vegetation resulted in low SOM content and the presence
of ochric epipedons in all of the studied soils. The genesis of
these soils accounts for the accumulation of calcium carbonate, soluble salts, and gypsum in the subsoil. Carbonate, clay
eluviation-illuviation, and salt accumulation are the dominant
pedogenic processes in these soils. Silt content increased toward
the surface indicating eolian activity. Clay content increased
with depth indicating illuviation of clay. Clay illuviation and
argillic horizon development within these soils is assumed to be
a relict feature from presumably more humid climates during the
Quaternary. Desert pavements cover the surfaces of these soils
and provide a unique obstacle for agricultural development. The
major restrictions to agricultural land use in the area are very low
infiltration rate, low permeability, and high erodibility. Proper
management practices should be adopted if such soils are to be
cultivated. В© 2005 Elsevier Ltd. All rights reserved.
1699 Soil-landform development of a part of the fold belt
along the eastern coast of Bangladesh
Sharif Hossain Khan Md., Parkash B. and Kumar S. Geomorphology 2005 71/3-4 (310-327)
The evolution of landforms and soils from the Jaldi and Maiskhali
anticlines and adjoining areas in a part of the coastal region of
the north-south trending fold belt of Bangladesh during the Late
Quaternary Period has been investigated. Based on the degree of
soil development and luminescence dating, eight soil geomorphic
units have been deciphered and grouped into four members (I-IV)
of a morphostratigraphic sequence for the study area. Various
soil geomorphic units included in different member/sub-members are: Member I - river floodplains and active tidal flats (<
500 years); Member II - distal Piedmont Plains and old tidal
flats (0.5-2 ka); Member III - proximal Piedmont Plains (6-10
ka); and Member IV - Mainland Higher and Lower Hillocks and
Island Hillocks (> 15 ka). Member IV is further subdivided
into Sub-member IVa - Island Hillocks (15-18 ka); Sub-member
IVb - Mainland Lower Hillocks (23-25 ka); and Sub-member
IVc - Mainland Higher Hillocks (30-35 ka). The youngest and
poorly developed soils of Member I show features related to
324
SOILS
hydromorphism. Moderately developed soils of Members II and
III show a fersiallitisation stage of pedogenesis. Member IV
includes вЂ�strongly developed soilsвЂ™ with a ferrugination stage
of pedogenesis. These soils also exhibit degradation and poor
birefringence of argillans and ferriargillans, indicating a significant change in conditions of pedogenesis, probably related to
a paleoclimatic change from a subhumid to semiarid phase (40
ka to about 16 ka) to a hot humid to subhumid phase (16 kapresent). Parent material composition and physiography also
have affected the pedogenesis in the area. Based on ages and
heights above the mean sea level for the five terraces recognized
in the study area, the overall base-level rise rates calculated are
about 3.6 mm/year (18 ka-present) for the Maiskhali Island and
2.86 mm/year (35 ka-present) for the mainland (Jaldi anticline).
These base level changes represent combined effects of eustatic
sea level and tectonic uplift due to folding. В© 2005 Elsevier B.V.
All rights reserved.
Physical properties
1700 The effect of soil water content and microbial activity
on restoring the structure of a Vertisol
Kostopoulou S.K. and Zotos A. Soil and Tillage Research 2005
82/2 (203-209)
Soils with high clay content are susceptible to structural damage,
if they are intensively cultivated. The structure of soils of the
Vertisol group has the tendency to restore as a result of wetting
and drying. Samples of a remoulded clayey soil were exposed to
seven successive wetting/drying (w/d) cycles, in order to study
the change of some structural features of the newly formed aggregates. To assess the effect of soil water content and microbial
activity, two different matric water potential ranges were used under sterile and non-sterile conditions. Aggregate size distribution
depended on both the water potential range and microbial activity
and approached to a steady state with increasing cycle number.
The water stability of the 2-1 mm aggregates was affected by
the activity of soil micro-organisms under wet conditions and by
forces of mechanical nature when the soil was reaching dryness.
All cases resulted in aggregates of reduced water stability with
respect to the natural aggregates. The <50 m aggregated particles initially preserved stability, but after a number of w/d cycles
they collapsed at a rate, depending mainly on the water potential
range. В© 2004 Elsevier B.V. All rights reserved.
1701 Andic soils of the Inland Pacific Northwest, USA: Properties and ecological significance
McDaniel P.A., Wilson M.A., Burt R. et al. Soil Science 2005
170/4 (300-311)
Holocene tephra from the cataclysmic eruption of Mount Mazama in southwestern Oregon is an important component of many
soils east of Cascade Mountains in the Pacific Northwest region. This article examines ecologically important properties of
these tephra-influenced soils. Characterization data from 886
soil horizons (384 pedons) of the region meeting criteria for andic soil properties or subgroup classification as andic or vitrandic
intergrades in Soil Taxonomy were used to compare morphological, chemical, and physical properties. Mazama tephra typically
comprises a significant portion of a surface mantle with textures
ranging from silt loam in areas distal to the tephra source to very
gravelly loamy coarse sand in proximal locations. Tephra has
been mixed to varying degrees with other parent materials across
the region. On average, volcanic glass only comprises 31.1% of
the 0.05 to 2-mm fraction and has a bimodal distribution, suggesting that some tephra was deposited with significant quantities of
dust or, that since deposition, considerable reworking and mixing
of glass has occurred. Oxalate-extractable Al ranges from 0.04 to
5.4% and provides the best indicator of colloidal surface activity
as indicated by P retention. Cation exchange capacity (CEC)
determined at field pH (ECEC) averages 7.8 cmolc kg-1 and is
less than one-third the CEC determined at pH 8.2, indicating
considerable variable charge and relatively low capacity of these
soils to store and supply nutrient cations. Mineralogical data
suggest that a reduced pool of secondary Al may be limiting
allophane formation in soil horizons with less tephra influence.
Volumetric water-holding capacity of ash-influenced horizons is
as much as twice that of underlying horizons and underscores
the importance of tephra in seasonally dry, forested ecosystems
of the Inland Northwest region. Copyright В© 2005 by Lippincott
Williams & Wilkins, Inc.
1702 The fate of the recombinant DNA in corn during
composting
Guan J., Spencer J.L. and Ma B.- L. Journal of Environmental
Science and Health - Part B Pesticides, Food Contaminants, and
Agricultural Wastes 2005 40/3 (463-473)
In order to make regulations that safeguard food and the environment, an understanding of the fate of transgenes from genetically
modified (GM) plants is of crucial importance. A compost experiment including mature transgenic corn plants and seeds of
event Bt 176 (Zea mays L.) was conducted to trace the fate of
the transgene cryIA(b) during the period of composting. In bin
1, shredded corn plants including seeds were composted above
a layer of cow manure and samples from the corn layer were
collected at intervals during a 12-month period. The samples
were tested for the transgene persistence and microbial counts
and also the compost was monitored for temperature. In bin
2, piles of corn seeds, surrounded by sheep manure and straw,
were composted for 12 months. A method combining nested
polymerase chain reaction (PCR) and southern hybridization was
developed for detection of the transgene in compost. The detection sensitivity was 200 copies of the transgene per gram of dry
composted corn material. Composting commenced on day 0,
and the transgene was detected in specimens from bin 1 on days
0 and 7 but not on day 14 or thereafter. The transgene in corn
seeds was not detectable after 12 months of composting in bin
2. Temperatures in both bins rose to about 50В°C within 2 weeks
and remained above that temperature for about 3 months, even
when the ambient temperature dropped below -20В°C. Extracts
from compost were inoculated onto culture plates and then were
incubated at 23 to 55В°C. Within the first 2 weeks of composting
in bin 1, the counts of bacteria incubated at 55В°C increased from
3.5 to 7.5 log10 , whereas those incubated at 23В°C remained at
about 7.5 log10 . The counts of fungi incubated at 45В°C increased
slightly from 2.5 to 3.1 log10 , but those incubated at 23В°C decreased from 6.3 to 3.0 log10 . The rapid degradation of the
transgene during composting of Bt corn plants suggested that the
composting process could be used for safe disposal of transgenic
plant wastes.
1703 Traditional and new deep soil tillage techniques in Italy
Pezzi F. Transactions of the American Society of Agricultural
Engineers 2005 48/1 (13-17)
A study evaluated the performance of traditional and alternative
implements for deep tillage. Three implements were compared,
a plow and two PTO-driven machines (spading machine and
rotary chisel), along with two soil depths, 0.30 and 0.40 m, and
two forward speeds. Tests were done on a level plot, containing
silty-clay soil. Forward speed, wheel slip, fuel consumption, and
energy at the PTO and drawbar were measured. Cloddiness of
the tilled soil was evaluated. The two PTO-powered implements
did not show advantages in terms of capacity, but they gave better
results in fuel consumption and in soil pulverization. Economic
evaluation showed lower unit costs (17% to 28%) for the spading
machine. В© 2005 American Society of Agricultural Engineers.
1704 Characterization of apparent soil electrical conductivity variability in irrigated sandy and non-saline fields in
Colorado
Farahani H.J., Buchleiter G.W. and Brodahl M.K. Transactions
of the American Society of Agricultural Engineers 2005 48/1
(155-168)
Recent advances in apparent soil electrical conductivity (ECa )
sensor technology have provided the opportunity to rapidly map
soil spatial variability for site-specific management. However,
characterizing (or identifying the causes of) the ECa variability
has remained difficult, with ECa and soil property (such as soil
water and clay content) relationships showing a wide range of
varying strength across fields. In this study, our objective was to
characterize the main soil properties that alter ECa and evaluate
the temporal variability of ECa and soil property relationships
SOILS
using multi-year measurements (1998 to 2003) in three centerpivot irrigated fields in eastern Colorado. Results show that
for the irrigated sandy and non-saline fields, ECa maps may be
viewed as surrogate maps for soil water content ( w ), clay, cation
exchange capacity, and/or organic matter content due to their
strong correlations (with correlation coefficients between 0.66
and 0.96). The experimental linear functions of ECa versus soil
properties changed over time when soil solution concentration
(ECw ) changed considerably. That finding was supported by
theory (the dual-pathway EC a model) showing the relationship
between ECa and soil stable properties (such as clay content)
to be governed by the status of the soil transient properties of
ECw and w at the time of the ECa mapping. The temporal
effect of varying soil temperature on ECa could be significant but
was not accounted for due to lack of temperature data. Results
collectively suggest that because of the lack of reliability of using
empirical ECa and soil property relationships for predictive purposes over time, on-site calibration of ECa versus soil properties
of interest are needed at each ECa mapping.
1705 Freezing of subarctic hillslopes, Wolf Creek basin, Yukon, Canada
Carey S.K. and Woo M.- K. Arctic, Antarctic, and Alpine Research 2005 37/1 (1-10)
Freezing processes were monitored at five sites within the Wolf
Creek basin, Yukon, Canada during the winter of 1998-1999.
Ground temperatures were measured using thermocouples in
hillslopes that had frost status ranging from permanent to seasonal. The timing of freezing and ground thermal regimes varied
among the five sites and was controlled by (1) the variation in
surface soil temperature, (2) frost status (seasonal vs. permanent), (3) moisture content of the active layer, (4) properties
of the soil profile, and (5) the presence/absence of subsurface
drainage. On slopes with permafrost, cooling was rapid and
two-sided freezing closed the active layer several months after
the onset of freezing. On a slope with seasonal frost only, dry
soil conditions allowed frost to penetrate to depth. In contrast,
a slope with seasonal frost that had continuous drainage, frost
depths were shallow due to heat advected from flowing water. A
simple one-dimensional conduction model with latent heat was
used to simulate freezing processes. Model performance varied
among the slopes, and results indicate that (1) conduction is the
predominant heat transfer mechanism during freezing, (2) latent
heat is the principal factor controlling frost front descent, and
(3) lateral flow significantly retards frost penetration because of
heat advection. This information is valuable in assessing spatial
variability within tile-based models and in predicting freezing,
which defines an effective end-of-season on lateral hydrological
processes. В© 2005 Regents of the University of Colorado.
1706 The effect of wildfire intensity on soil aggregate stability in the Cadiretes Massif, NE Spain
Вґ
Ubeda
X. and Bernia S. IAHS-AISH Publication 2005 -/299 (3745)
This paper reports on the changes in soil aggregate stability after
a wildfire, with the focus on the effects of fire intensity on soil
structure. The aggregate stability of soils burned at different
fire intensities was tested using the TDI method. The samples
were taken from three areas burned at three fire intensities and
the results of the aggregates were compared with those from
an unburned forest. The study area is located in the Cadiretes
massif, northeast Spain. The analyses were undertaken just after
the fire in 1994, and again in 1995 and 1997. The most stable
aggregates compared to those from the control area were those
sampled just after the fire. The disaggregation was highest in
1995 and lowest in 1997. The fire did not disturb the stability
of the aggregates immediately after burning. After the fire the
aggregates did not become unstable and, in contrast, they were
even more stable than those sampled in the control forest.
1707 Nearreal time variability of soil moisture and temperature under different land use and cover: The Alabama
Mesonet
Tsegaye T.D., Metzl R., Wang X. et al. Journal of Environmental
Hydrology 2005 13/- (13p)
The Alabama Mesonet (ALMNet) has been established to pro-
325
vide near-real-time data to conduct research that aims to ensure the security, quality, and quantity of the NationвЂ™s natural
resources. The ALMNet is made up of eleven combination meteorological/soil profile stations and twelve soil profile stations
positioned at 23 locations in eight counties. The stations are included in the USDA NRCS SCAN network. Meteorological and
soil profile data collected by ALMNet include temperature (air
and soil), humidity, solar radiation, wind (speed and direction),
soil heat flux, soil moisture and precipitation. The objectives
of the ALMNet are to: (i) serve as a validation site for current
and future satellite missions of monitoring soil moisture (e.g.
the Aqua satellite) and archive both atmospheric and hydrologie
related data: (ii) study soil moisture and temperature variability
at different time scales and under different land use and land
cover: (in) model soil water content and temperature from observable climate data and compare model estimates in terms of
energy partitioning: (iv) strengthen outdoor research and training
facilities for both undergraduate and graduate students: and (v)
establish an Online Internet Service for extension agents, farmers
and interested individuals to visualize climate related data. Our
long-term vision is to complete detailed hydrological and meteorological process analyses for northern Alabama and southern
Tennessee in collaboration with scientists from NASA, USDA
and other Universities. We also hope to expand the recording
sites throughout Alabama as our resources permit.
1708 Determining long-term effective groundwater recharge by analyzing vertical soil temperature profiles at meteorological stations
Cheviron B., GuВґerin R., Tabbagh A. and Bendjoudi H. Water
Resources Research 2005 41/9 (1-6)
[1] Vertical water seepage in soils results in convective heat transport that modifies the temperature profiles and their variations
with time; consequently, there is a relationship between temperature profile variations with time and the vertical Darcy velocity
associated with the seepage. Considering the annual sinusoidal
time variation of the temperature at the soil surface, it can be
shown that convective heat transport has a significant effect on
the amplitude damping with depth and a negligible effect on the
phase lag with depth of the temperature time signal. Standard
meteorological stations constitute a relatively dense network,
and we show that their routinely collected data can be used to
determine an average value of the vertical Darcy velocity, uZ ,
representing the effective annual recharge over long time periods (several years). A new procedure for determining uZ from
these temperature records is presented. First, the layering of
the medium is determined by an electrical sounding. Then the
thermal properties of each layer are inferred from the phase lag
with depth. Finally, uZ is calculated from the amplitude damping.
After having tested this approach with synthetic data, we used
the 1984-2001 Abbeville (Somme, France) data to determine the
average recharge over six 3-year periods. The results are in good
agreement with classical meteorological recharge estimates and
show a significant increase in the recharge during the last 3year period, consistent with the observed phreatic 2001 flood
event. Specific temperature measurements at appropriate depths
and time steps could drastically improve the sensitivity of the
method. Copyright 2005 by the American Geophysical Union.
1709 Influence of water regime and N availability on the
emission of nitrous oxide and carbon dioxide from tropical,
semi-arid soils of Chiapas, Mexico
Ponce- Mendoza A., Boeckx P., Gutierrez- Miceli F. et al. Journal of Arid Environments 2006 64/1 (137-151)
The concentration of nitrous oxide (N2 O) and carbon dioxide
(CO2 ) in the atmosphere has increased considerably over the last
century, but few studies are available showing their production
from soils in semi-arid areas. Soils from the tropical semiarid Central Depression of Chiapas were sampled from fields
cultivated with maize (MAI treatment), under canopy of Acacia angustissima (TIMBRE) or outside the canopy of the trees
(OUT), adjusted to 40%, 60%, 80% or 100% of water-holding
capacity (WHC) and amended with 0, 15 or 50 mg (NH4 NO3 )-N
kg-1 dry soil. The production of N2 O, CO2 and concentrations of
NH +4 , and NO-3 were monitored in the laboratory under aerobic
conditions. Production of N2 O in the first 3 days was significantly
larger from the MAI and OUT soils, compared to the TIMBRE
326
SOILS
soil, while the addition of 50 mg inorganic N doubled the production of N2 O. In all treatments, soil at 100% WHC had the largest
production of N2 O. The emission of CO2 was significantly larger
from soils at 60% and 80% WHC compared to the soil at 40%
and 100% WHC, although the addition of inorganic N had no
significant effect on CO2 emission. The application of inorganic
N and the absence of vegetation increased the production of N2 O.
В© 2005 Elsevier Ltd. All rights reserved.
1710 Quantitative characteristics of soil aggregates under different vegetations in upper reach of Minjiang River
(Chinese)
Ning L., Shi H., Zhou H. and Liu S. Chinese Journal of Applied
Ecology 2005 16/8 (1405-1410)
Quantitative analysis on the soil aggregates under dark coniferous forest, coniferous and broad-leaved mixed forest, fargesia
under the gap of dark coniferous forest, and sclerophyllous oaks
(Quercus semicarpifolia) at Wolong Natural Reserve in the upper
reach of Minjiang River showed that wet-sieving soil aggregates
were of logarithmic-normal distribution, and the geometric mean
diameters were negatively correlated to geometric standard deviation. The aggregates under coniferous and broad-leaved mixed
forest and sclerophyllous oaks had larger sizes than those under other vegetations. The range of fractal dimension of soil
aggregates was 2.40-2.78, along with more aggregates less than
0.25 mm in size. The fractal dimension of soil aggregates under
dark coniferous forest and fargesia were larger than that under
other vegetations. The soil aggregates with 3-1 mm and 1-0.5
mm in size had a higher stability, while those with > 10 mm
and 0.5-0.25 mm in size were in adverse. The aggregate stability
index of soil under coniferous and broad-leaved mixed forest was
the highest, followed by that under sclerophyllous oaks, fargesia
under the gap of dark coniferous forest, and dark coniferous forest, which meant that coniferous and broadleaf mixed forest and
sclerophyllous oaks were favorable for soil aggregate stability.
Significant correlations were found among the three quantitative
characteristics, which could be used to indicate the stability of
soil aggregates.
Soil water
1711 Preferential water flow in a glacial till soil
Jansson C., Espeby B. and Jansson P.- E. Nordic Hydrology 2005
36/1 (1-11)
Measured and simulated response of runoff during snowmelt has
suggested that preferential water flow occurs as part of the infiltration process in glacial till. However, only a few quantitative
studies have been presented. TDR measurements of soil water
content were performed during the growing period in a till slope
(7-10%) outside Stockholm. Soil cores were used to determine
the water retention curve and the saturated hydraulic conductivity.
A physically based one-dimensional model was used to simulate
soil water dynamics in the slope. Two simulation approaches
were used: a strict one-domain Darcian approach and a two-domain approach accounting for a bypass of the matrix flow system.
The measured response of soil water content occurred within the
first few hours after rainfall. This was best represented by the
two-domain approach, while the response for the one-domain
approach was significantly delayed with time and depth. The
general behaviour of the soil water content throughout the season was, however, best simulated with a one-domain approach.
The results indicated that preferential flow patterns through the
unsaturated zone does not need to be considered to describe the
seasonal pattern in glacial till soil. However, the results also point
out that the purpose of the simulation is decisive when choosing a
simulation approach, depending on whether the general soil water content over the season or the instant behaviour immediately
after rainfall is of major interest. В© IWA Publishing 2005.
1712 Development and field validation of the pestfate model
in southern Ontario
Bera P., Prasher S.O., Madani A. et al. Transactions of the
American Society of Agricultural Engineers 2005 48/1 (85-100)
A new pesticide movement model called PESTFATE (PESTicide Fate and Transport in Environment) has been developed by
combining DRAINMOD, a well-known water table management
model, and the pesticide submodel of PESTFADE. The pesticide
sorption in the new model is based on two different techniques,
namely, conventional mechanism and a new two-stage sorption
method called Gamble kinetics. The model was validated by
comparing the simulated midspan water table depths and atrazine [2-chloro-4-ethylamino-6-isopapylamino-1, 3, 5-triazine]
concentrations against an independently collected dataset from
a research site in southern Ontario. The experimental field consisted of 16 plots with two different water table management and
four different tillage practices, replicated twice. Only the plots
with conventional tillage and controlled drainage were used in
this study. The model performed well in predicting the daily
water table depths. Although the intercept and slope of the regression between the observed and predicted water table depths
were significantly different from 0 and 1, respectively, the model
efficiencies for 1992, 1993, and 1994 were 28%, 81%, and 64%,
respectively, which shows a better accuracy for the last two years
of the study. The normalized standard errors were within 15%
to 20%, which indicates good model performance for water flow
simulation. However, the correlation between the observed and
simulated pesticide concentrations with both the conventional
and Gamble kinetics was poor. Moreover, the Gamble kinetics
did not significantly improve pesticide simulations (P < 0.05)
as compared to the conventional method. The experiments were
conducted on Brookston clay loam soil, which is known for
developing soil cracks and consequently preferential flow. This
could be one of the reasons for poorer model performance, especially with the Gamble kinetics. This was not the case in
previous studies, which reported better simulation results with
the new sorption mechanism, so the model requires additional
field testing before any concrete conclusions can be drawn about
its performance. There is also a need to test the model with other
pesticides. В© 2005 American Society of Agricultural Engineers.
1713 Hydraulic conductivity of a silt loam soil as affected
by sample length
Fuentes J.- P. and Flury M. Transactions of the American Society
of Agricultural Engineers 2005 48/1 (191-196)
Soil hydraulic conductivity is often measured with small laboratory samples. Due to sampling artifacts or spatial variability, small-scale laboratory samples may not yield representative
conductivity measurements. The objective of this study was to
analyze the effect of sample length on the saturated and nearsaturated hydraulic conductivity (K). An undisturbed soil core
of 9 cm diameter and 25 cm length was extracted from the A
horizon of a no-till, silt loam soil, and K was determined at hydraulic heads (matric potential heads) of 0, -4, -8, -12, -16, and
-22 cm-H2 O under steady-state flow conditions. The core was
then dissected incrementally from the bottom in 5 cm segments.
At each dissection step, the remaining core and the cutoff core
were re-saturated, and K was determined. Measured K varied
considerably with core length, with the saturated conductivity
being much more variable than the unsaturated conductivities.
The use of consecutive 5 cm core segments to determine the effective K resulted in an underestimation of the conductivity compared to direct measurements on longer cores, possibly caused by
smearing or compaction of cut surfaces during core dissection.
Effective K determined from 5 cm core segments matched well
with directly measured K only at hydraulic heads more negative
than -16 cm-H2 O. The results of this study highlight that small
cores on the order of a few cm may not be representative of a
larger soil profile such as the plow layer or crop root zone. В©
2005 American Society of Agricultural Engineers.
1714 Economic analysis of subsurface drip irrigation lateral
spacing and installation depth for cotton
Enciso J.M., Colaizzi P.D. and Multer W.L. Transactions of the
American Society of Agricultural Engineers 2005 48/1 (197-204)
Cotton lint yield, seed mass, fiber quality parameters, gross return, and net return were compared for subsurface drip irrigation
(SDI) lateral spacing and installation depth in a clay loam soil in
western Texas for three seasons. Drip laterals were spaced either
in alternate furrows (2 m) or beneath every planted bed (1 m),
and installation depths were either 0.2 or 0.3 m beneath the soil
surface. Net return was gross return minus fixed and variable
SOILS
costs. Fixed costs included the annual payment for financing
the initial investment of SDI materials and installation (5.00%
interest over 10 years), the annual land lease, and the annual
depreciation of the SDI system. Variable costs were those associated with cotton production and were similar for the two drip
lateral spacings. Lint yield, seed mass, and gross and net returns
were significantly greater for the 1 m lateral spacing in the first
two seasons, but these parameters were significantly greater for
the 2 m lateral spacing in the third season. These parameters were
consistently greater (either numerically or significantly) for the
0.3 m lateral depth in all seasons. Most fiber quality parameters
were not significantly different, and no consistent trends were
observed. Lint yields ranged from 640 to 1,635 kg ha-1 , and net
returns ranged from -$395 to $1,005 ha-1 . The low lint yield
and resulting net loss were due to a germination failure in the
second season for the alternate furrow spaced laterals. Additional seasons of study are required before conclusions might be
drawn concerning the most economic lateral spacing for cotton
production in the Trans-Pecos region of Texas, but the 0.3 m
lateral depth resulted in greater net returns than the 0.2 m lateral
depth.
1715 A precise irrigation system with an array of nozzles
for plug transplant production
Ohyama K., Murase H., Yokoi S. et al. Transactions of the American Society of Agricultural Engineers 2005 48/1 (211-215)
A precise irrigation system with a 6 x 12 array of needle-like
nozzles was developed for plug transplant production using 72cell plug trays. When a command for irrigation is given to the
system, all of the nozzles are directly inserted into the corresponding cells at the same time to discharge a predetermined
amount of water or nutrient solution. The amount of irrigated
water from each nozzle (Q) can be controlled by adjusting the
discharge time to keep the solenoid valve open (T) and by discharge pressure (P). The objectives of the present study were:
(1) to obtain quantitative data for the control of Q, and (2) to
examine the performance of the system during a plug transplant
production period of 20 days. By adjusting T of each nozzle
individually and P, a uniform distribution of Q was achieved over
the tray. Consequently, a high value of Christiansen coefficient
of uniformity was obtained (97.2% to 98.4%). During the plug
transplant production period, the volumetric water content in
each cell could be controlled by using the system without any
growth deterioration of the transplants owing to the root damage
caused by the nozzle insertion into the substrate. These results
demonstrate that this system is feasible for precise irrigation
management of plug transplant production. В© 2005 American
Society of Agricultural Engineers.
1716 Mechanisms of surface runoff genesis on a subsurface
drained soil affected by surface crusting: A field investigation
Augeard B., Kao C., Chaumont C. and Vauclin M. Physics and
Chemistry of the Earth 2005 30/8-10 (598-610)
Artificial drainage has been subject to widespread criticism because of its impact on water quality and because there is suspicion that it may have detrimental effects on flood genesis. The
present work aims at a better understanding of the mechanisms
controlling infiltration and surface runoff genesis, particularly
in soils with artificial drainage and affected by surface crusting.
A field experiment was conducted during one drainage season
(November 2003-March 2004) in the Brie region (80 km east
of Paris, France) on a subsurface drained silty soil. Water table
elevation and surface runoff were monitored above the drain
and at midpoint between drains. Soil water pressure head was
measured at various depths and locations between the midpoint
and the drain. Soil surface characteristics (microtopography and
degree of structural and sedimentary crust development) were
recorded regularly on the experimental site and on other plots
of various drainage intensities. The results show that the first
surface runoff events were induced by high water table. However, runoff was higher at midpoint between the drains because
water table reached the soil surface at that point, thus considerably reducing infiltration capacity compared to that above the
drain. Comparing different plots, the area with older drainage
installation (1948) yielded the most surface runoff. Wider drain
spacing, smaller drain depth and possible plugging may have led
to a greater area of saturated soil between drains. During the
327
winter period, the impact of raindrops induced the formation of a
structural crust on the soil surface. Furthermore, the development
of the sedimentary crust, which was favored by water actually
flowing on the soil surface during the high water table periods
could be correlated with surface runoff volume. The formation
of this crust had a significant impact on runoff occurrence at the
end of the winter. Therefore, poorly drained fields presented
more favorable conditions for both Horton type runoff and saturation excess runoff. Drainage effectively reduces surface runoff
occurrences not only by lowering the water table in winter but
also by limiting soil surface sealing. В© 2005 Elsevier Ltd. All
rights reserved.
1717 Can forest transformation help reducing floods in
forested watersheds? Certain aspects on soil hydraulics and
organic matter properties
Wahl N.A., WВЁollecke B., Bens O. and HВЁuttl R.F. Physics and
Chemistry of the Earth 2005 30/8-10 (611-621)
Former floodplains in many European countries increasingly suffer from serious floods due to intensified human activity. These
floods have caused safety and ecological problems as well as they
have resulted in economic losses in agricultural used watersheds.
In this context, the influence of the management practice of forest
transformation in forested areas on soil hydraulic properties is
presented and discussed as a means of preventing such disasters
at a reasonable cost and during a foreseeable period. Investigations were carried out in northeastern Germany on forest stands
differing in tree populations and stand structure. It was found
that infiltration capacity and hydraulic conductivity K exhibit
overall low values nevertheless the tree species. This finding appears to be related to water repellency, the predominating texture,
and a poor macroporosity. During the different stages of forest
transformation, the type and amount of soil organic matter and
humus in the litter layer change, leading to a decrease of the water
capacity of the litter layer and the uppermost part of the mineral
soil. Furthermore, these changes affect soil properties connected
with water repellency. It is concluded that for the approximate
duration of one century the practice of forest transformation does
not contribute to flood prevention through enhanced infiltration
capacity or water retention. В© 2005 Elsevier Ltd. All rights
reserved.
1718 Temporal dynamics of soil water in oak forest stand of
Southern Slovakia
TuЛ‡zinskВґy L. Ekologia Bratislava 2005 24/3 (304-313)
Time and spatial variability of the soil water depends on the
weather characteristic course, on soil hydrophysical characteristics and on forest stand transformation influence. Analysis of
soil water available for plants during the growing season shows
that the water dynamics in the soil under the oak forest stand
is most intense in the upper (0-50 cm) layers of the soil profile.
Water uptake and loss from this soil layer results in transition
of the soil water from one category to another, especially due to
the osmotic preassure of the soil and the water active transport
via fine roots. At the beginning of the growing season capillary
movable water category prevails in the soil profile with easy
available water supply. Radiation and air temperature increase
leads to the gradual decrease of soil water content. Increase of
evapotranspiration (> 5 mm.day-1 ) is folowed by the process of
water supply decrease. During the culminating drying off period
(July, August) the soil water supply decreases to the category
of capillary immovable water. During extremely dry season
the water supply in the soil can decrease to the wilting point
level. Soil water becomes capillary bound and non-available
for plants. Loss of contact between the fine roots and water
results in decrease of transpiration and assimilation. Premature
fall off of physiologically weakened leaves is recorded. Under
such conditions the oak resistance towards damaging factors is
decreased.
1719 Flux-saturation relationship for unsaturated horizontal flow
Evangelides C., Tzimopoulos C. and Arampatzis G. Soil Science
2005 170/9 (671-679)
The prediction of unsaturated flow is a never-ending quest for
many scientists. Many methods exist with their corresponding
328
SOILS
advantages and disadvantages, such as semianalytic, finite difference, finite element, finite control volume, and flux-saturation.
The last one, even though it belongs to the semianalytic group,
is very interesting due to its simplicity and the way it approaches
the physical problem. During laboratory research, a new intuitive
monoparametric fitting function was used for F( ). The purpose
of this research was to examine the range of variation of the new
fitting function coefficient and the feasibility to replace it with a
constant. A series of experiments was carried out on horizontal
absorption under constant-head conditions, using three different
soil types, to measure their F( ) function. F( ) values were
also obtained for four other soils, using different methods. The
soils that were examined were characterized from silt to sand,
according to the textural triangle of the United States Department of Agriculture. Actual F( ) functions were then calculated
in each soil. The proposed F( ) function was compared with
the limiting F( ) function for linear and Dirac soil and with
preexisting ones. The results were satisfactory both in shape and
in quantity, leading to a new expression for F( ) for all soil types.
Copyright В© 2005 by Lippincott Williams & Wilkins, Inc.
1720 Modeling water flow behavior where highly treated effluent is applied to soil at varying rates and dosing frequencies
Hassan G., Reneau Jr. R.B., Hagedorn C. and Saluta M. Soil
Science 2005 170/9 (692-706)
There is a need for alternative on-site wastewater systems (OWS)
that can be used in soils and on sites not suitable for conventional
OWS (septic tank and gravity dispersal) while minimizing ground
and surface water degradation. One method to accomplish this is
to apply highly treated effluent (HTE), using a technology such
as a subsurface drip irrigation system (SDIS), where effluent is
dispersed uniformly to soil and the dosing frequency can be controlled. Since there are a large number of factors that can affect
OWS function, the ability to evaluate these factors by using a
simulation model would greatly improve our ability to design
OWS that solve problems while having minimal environmental
impact. This study was conducted to determine the potential
to simulate HTE [recirculating media filter effluent (RMFE)]
flow, soil water content and potential, and changes in soil water
mass balance using HYDRUS-2D (a numerical model), in which
RMFE was applied at varying rates (518, 1036, and 2071 cm 3
d-1 ) and dosing frequencies (6, 12, and 24 doses per day) to soil
columns designed to simulate a SDIS. Fecal coliform numbers
were used to measure the effectiveness of these treatments. We
hypothesized that fecal coliform numbers would decrease when
effluent was applied in smaller (more frequent) doses. Results
showed that HYDRUS-2D could be successfully used to predict
RMFE flow, soil water potential and moisture content, and soil
mass balance. Although dosing RMFE more frequently had no
effect on fecal coliform numbers at the two lowest application
rates (518 and 1036 cm3 d -1 ), there was a significant decrease in
fecal coliforms as dosing frequency increased at the highest rate
of application (2071 cm3 d-1 ). Copyright В© 2005 by Lippincott
Williams & Wilkins.
1721 Soil hydraulic properties in a marly gully catchment
(Draix, France)
Esteves M., Descroix L., Mathys N. and Lapetite J.M. Catena
2005 63/2-3 (282-298)
Runoff is one of the main factors controlling gully development. Concentrated flow erosion occurs where flow discharge
and velocity exceed critical values. In Southern French Alps,
in black marl gully catchments, runoff from hillslopes occurs in
the form of Hortonian overland flow because rainfall intensities
exceed the infiltration capacity of the soil. In such a situation,
spatial variability of infiltration capacities is critical for describing the runoff production. This study reports detailed field measurements of near-saturation and saturated infiltration properties:
capillary sorptivity (S) and hydraulic conductivity (K). A total
of 140 infiltration tests were conducted using tension disc and
ponded ring infiltrometers on 6 different regoliths (weathering
profile) encountered in a marly gully catchment. The main objectives were to improve our knowledge of the spatial variability
of infiltration in black marl areas and to compare different field
and data analysis methods. Hydraulic conductivity values K(h)
at supply pressure heads (h) ranging from h = - 100 up to h =
0 mm were calculated using steady state flow and WoodingвЂ™s
equation [Wooding, R.A., 1968. Steady infiltration from shallow
circular pond. Water Resour. Res. 4 (6), 1259-1273]. K(h = 0
mm) was also estimated from the ponded ring infiltrometer data
set. The estimation of sorptivity was based on transient flow and
the solution of Haverkamp et al. [Haverkamp, R., Roos, P.J.,
Smettem, K.R.J., Parlange, J.Y., 1994. Three dimensional analysis of infiltration from the disc infiltrometer. 2. Physical based
infiltration equation. Water Resour. Res. 30 (11), 2931-2935].
Three methods were used to analyse tension disc infiltrometer
data: multiple radii, multiple potential and single test. Only the
multiple radii method was found not suitable in our context due to
a large spatial variability in the infiltration properties over small
distances. The other methods gave similar estimates of the hydraulic conductivity. The hydraulic conductivity K(h) ranged up
to two orders of magnitude. This result confirms the role played
by structural voids when the regolith is at near saturation. The
dispersion of the estimates of field saturated hydraulic conductivity is larger than unsaturated values. The spatial differences
found are explained by the topographical position and by the
regolith structure observed for the 6 sites. An analysis based on
the ponding time show that the regolith type plays an important
role in the dynamic of the runoff production. В© 2005 Elsevier
B.V. All rights reserved.
1722 Ecological characteristics of soil water and its relations
to landform and vegetation in a small semiarid watershed in
a loess hilly area of China
Liu W.Z., Hu M.J., Li F.M. and Zhang X.C. International Journal of Sustainable Development and World Ecology 2005 12/3
(326-333)
There is an urgent need to study soil water resources and ecohydrological characteristics in depth so as to carry forward ecological environmental construction in the Loess Plateau. Soil
moisture was measured to a depth of 5 m on 11 sites with different landforms and land uses in a transect of the Zhonglianchuan
watershed during 2002. The watershed is located in the northern
Yuzhong County, Gansu Province, and is part of a semiarid and
loess hilly area. There were different types of soil moisture
variations in 2002 on the 11 sites. Soil moisture contents were
low on all sites, and the average water contents at 2 to 5-m depth
were usually lower than 10% by weight, and the lowest water
contents were found in slope land under Medicago sativa and
Caragana korshinskii vegetation. The dry soil layer is common
in this area, not only under planted vegetation but also under
natural vegetation. The soil moisture in a slope segment or
area can be increased by collecting and harvesting surface runoff
from upslope areas. One effective way to collect runoff is by
constructing level terraces, alternating with sloping lands. The
proportion of various grasslands, acreage of alfalfa, and sustainable development of the region should be further studied in order
to successfully convert cultivated land into grassland.
1723 Water films and scaling of soil characteristic curves at
low water contents
Tuller M. and Or D. Water Resources Research 2005 41/9 (1-6)
[1] Individual contributions of capillarity and adsorptive surface
forces to the matric potential are seldom differentiated in determination of soil water characteristic (SWC) curves. Typically,
capillary forces dominate at the wet end, whereas adsorptive
surface forces dominate at the dry end of a SWC where water
is held as thin liquid films. The amount of adsorbed soil water
is intimately linked to soil specific surface area (SA) and plays
an important role in various biological and transport processes
in arid environments. Dominated by van der Waals adsorptive
forces, surface-water interactions give rise to a nearly universal
scaling relationship for SWC curves at low water contents. We
demonstrate that scaling measured water content at the dry end
by soil specific surface area yields remarkable similarity across
a range of soil textures and is in good agreement with theoretical predictions based on van der Waals interactions. These
scaling relationships are important for accurate description of
SWC curves in dry soils and may provide rapid and reliable
estimates of soil specific surface area from SWC measurements
for matric potentials below -10 MPa conveniently measured with
the chilled-mirror dew point technique. Surface area estimates
acquired by fitting the scaling relationship to measured SWC
data were in good agreement with SA data measured by standard
SOILS
methods. Preliminary results suggest that the proposed method
could provide reliable SA estimates for natural soils with hydratable surface areas smaller than 200 m2 /g. Copyright 2005 by the
American Geophysical Union.
1724 Non-linear radiation for bidimensional Richards equation in subsurface agricultural drainage (Spanish) (RadiaciВґon
no lineal en la ecuaciВґon de Richards bidimensional aplicada al
drenaje agrcola subterrВґaneo)
Zavala M., Fuentes C. and Saucedo H. Ingenieria Hidraulica en
Mexico 2005 20/4 (111-119)
A mechanistic approach is presented to simulate the hydraulic operation of a subsurface agricultural drainage system that consists
in numerically coupling the bidimensional Richards equation for
the water flow in the soil with the continuity equation and a
resistance law for the water flow in the drain. This coupling is
made by imposing a non-linear radiation condition on the drain
perimeter (Zavala et al., 2003). By using experimental data,
the description capacity of both the non-linear radiation condition and the classical approximation reported in the literature as
seepage-face condition is evaluated. By comparison with experimental information, it is shown that the seepage-face condition
overestimates drainage flow and the recession of the water table,
due to the fact that it assumes a null resistance in the saturated
soil-drain interface. The experimental validation allows to conclude that the description of mass and energy transferences in
an agricultural subsurface drainage system during the recession
of the water table must be made by imposing the non-linear
radiation condition in the circumference of the drain.
1725 Spatial heterogeneity of soil moisture after raining at
forest-grassland landscape boundary in hilly area of Loess
Plateau (Chinese)
You W., Zeng D., Liu M. et al. Chinese Journal of Applied
Ecology 2005 16/9 (1591-1596)
Soil moisture is a main factor limiting vegetation restoration in
semi-arid region. In this paper, the spatial variability of different
layers soil moisture after raining at the forest-grassland boundary in hilly area of Loess Plateau were studied by traditional
and geostatistical analysis methods. The results showed that the
moisture content in surface (0-10 cm) and subsurface soil layer
(10-20 cm) of grassland was higher than that of forestland. The
two layers soil moisture content at forest-grassland boundary
showed a small variation but an obvious ecological distribution.
By using moving split-window techniques, it was obtained that
the width of edge influence in surface and subsurface layer was
8 and 6 m, respectively. Geostatistical analyses showed that the
spatial distribution of two layers soil moisture had a pure nugget effect in grassland, linear model in forestland, and spherical
model in forest-grassland boundary. The spatial heterogeneity of
two layers soil moisture was higher at forest-grassland boundary
than at forestland and grassland, which had a stronger spatial dependence and autorelation. Kriging maps expressed the spatial
structural characters. The distribution of soil moisture in two
layers showed a strip shape near forest edge, and a patch shape
far from the edge.
1726 Simulation of energy and water balance in Soil-Vegetation-Atmosphere Transfer system in the mountain area of
Heihe River Basin at Hexi Corridor of northwest China
Kang E., Cheng G., Song K. et al. Science in China, Series D:
Earth Sciences 2005 48/4 (538-548)
In the mountain area of inland Heihe River Basin at Hexi Corridor
of northwest China during the vegetation growing season from
May to September, the Simultaneous Heat and Water (SHAW)
model of Soil-Vegetation-Atmosphere Transfer (SVAT) system
is applied to simulating and studying energy and water balance
of the soil-residue-plant canopy layers in the Picea crassifolia
forest and the grassland by the forest at the shaded slope and
the grassland at the sun-facing slope. The simulation of energy
balance indicates that net radiation of the grassland at the sunfacing slope is more than that of the Picea crassifolia forest and
the grassland by the forest at the shaded slope. The energy outgoing components are the first latent heat and next sensible heat
from the grassland both at the shaded slope and the sun-facing
slope, but those at the former are less. The energy outgoing
components are the first sensible heat and next latent heat from
329
the Picea crassifolia forest. The composition and distribution
of energy in the soil-residue-plant canopy layers in the Picea
crassifolia forest and the grassland by the forest at the shaded
slope make the soil layer receive less energy, which therefore,
especially the forest possesses the energy conditions for soil water conservation. The simulation of water balance indicates that
the water loss of the grassland at the sun-facing slope is mainly
caused by soil evaporation, while evapotranspiration of the Picea
crassifolia forest and the grassland by the forest at the shaded
slope is less than that of the grassland at the sun-facing slope.
Half of the evapotranspiration of the Picea crassifolia forest and
the grassland by the forest at the shaded slope is consumed by
transpiration. After precipitation, the soil water storage is increased much more for the Picea crassifolia forest and also more
for the grassland by the forest at the shaded slope. Therefore the
shaded slope vegetation, especially the forest is favorable for soil
water storage. Copyright by Science in China Press 2005.
Chemistry
1727 Agronomic and environmental impacts of a single application of heat-dried sludge on an Alfisol
Gavalda D., Scheiner J.D., Revel J.C. et al. Science of the Total
Environment 2005 343/1-3 (97-109)
A field experiment was conducted on Alfisols in South-West
France to assess the agronomic and environmental impacts of
a single application of heat-dried sludge pellets at 11.1 Mg dry
matter ha-1 . The sludge pellets, with a moisture level of 9.5%,
were spread on an irrigated crop of maize (Zea mays L.). This
treatment was compared with inorganic fertilization (urea and
diammonium phosphate mixed with KCl). Soil properties, yield
and the composition of maize and the quality of drained water
were monitored over 1 year to detect any changes resulting from
sludge application. Amongst several determined soil properties,
only two were significantly modified by the sludge application:
The nitric nitrogen stock of the soil was higher in the inorganic
fertilized plot, whereas Olsen-P soil content was higher in the
sludge-amended plot. Agronomic recovery rates of N and P
added by sludge were high: For the first crop following application, total amounts of N and P supplied by the sludge had the
same efficiency as approximately 45% of the N and P amounts
supplied by inorganic fertilizer. This ratio was 7% for the N
uptake by the second maize crop. The quality and quantity of
maize were equally good with both types of fertilization. During
the 2 years following sludge spreading, N leaching remained as
low in the sludged plot as in the inorganically fertilized one. The
Cu, Zn, Cr, Cd, Pb and Ni composition of the drainage water was
affected by neither of the types of amendment. From the heavymetal contents of the soil, water and maize monitored over 1 year
in the field experiment and from literature data for cow manure
and atmospheric emissions, a theoretical balance between crop
soil heavy-metal input and output over one century was drawn
up. The long-term impact of cow manure on Zn, Ni and Cr in soil
is higher than that of the studied heat-dried sludge. Obviously,
sludge tended to cause a strong increase in soil Cu storage, valued
for these soils, which are otherwise very Cu deficient. В© 2004
Elsevier B.V. All rights reserved.
1728 N fertilisation, soil type and cultivars effects on N use
efficiency in tef [Eragrostis tef (Zucc.) Trotte]
Tulema B., Zapata F., Aune J. and Sitaula B. Nutrient Cycling in
Agroecosystems 2005 71/2 (203-211)
Tef [Eragrostis tef (Zucc.) Trotte] is a major staple crop in
Ethiopia and a large proportion of the imported fertiliser is being
applied to tef fields. However, since the 1980s the yield on
farmersвЂ™ fields has stagnated. Response of the crop to applied
fertiliser is influenced by several factors. We aimed to study
the fertiliser N use efficiency (FNUE) of four tef varieties from
ammonium sulphate and urea on different soil types with the
help of the 15 N isotopic dilution technique. Three experiments
were conducted under greenhouse and field conditions. On a
typic Eutrocrept soil, higher percent N derived from fertiliser
(% Ndff) and % FNUE were obtained for all the tested tef varieties when the N source was urea, while percent N derived from
330
SOILS
soil (% Ndfs) was higher for ammonium sulphate. The mean
% FNUE for urea and ammonium sulphate was 49 and 34%,
respectively. When the varieties were grown on a Nitosol or a
Vertisol and ammonium sulphate was applied, the % Ndff, the
total and fertiliser N yield and % FNUE of the tef varieties were
higher on a eutric Nitosol compared to the Vertisol. The mean
% FNUE was 61.3 for the Nitosol and 27.8 for the Vertisol. In
an вЂ�on farmвЂ™ experiment, relatively higher FNUE (33.3%) was
obtained on an Andosol compared to Vertisols (17 and 27%).
The tested varieties showed no difference in FNUE. As tef is
the most important crop grown on Vertisols in Ethiopia, the low
FNUE has a direct negative implication for the livelihood of the
farmers and the environment. В© Springer 2005.
1729 Does pyrite oxidation contribute to the acidification of
tropical peat? A case study in a peat swamp forestin Central
Kalimantan, Indonesia
Haraguchi A., Akioka M. and Shimada S. Nutrient Cycling in
Agroecosystems 2005 71/1 (101-108)
The chemical properties of peat pore water in the basin of the Sebangau River and Lahei district, Central Kalimantan, Indonesia,
were studied. We analyzed major ions, pH, electrical conductivity (EC) and redox potential (Eh) of the peat pore water with
reference to their vertical profile. We evaluated the contribution
of sulfates to the acidi.cation of peat by including data from Furen
mire, eastern Hokkaido, Japan. The coastal peat of Furen mire
and the peat in Paduran in the lower basin of the Sebangau River
included extraordinarily high concentrations of sulfates (> 1000
mg/l) compared to the peat in the middle and upper basins of the
river (< 10 mg/l). High concentrations of sulfates, however, did
not lead to a low pH for the peat. The present findings suggest that
the acidification of the peat pore water is subject to the production
of organic acids originating from peat decomposition, rather than
the production of sulfuric acid produced by pyrite oxidation in
the underlying mineral sediments. В© Springer 2005.
1730 Simulating processes of soil phosphorus in geologically
young acidic soils of Finland
Yli- Halla M., Tattari S., BВЁarlund I. et al. Transactions of the
American Society of Agricultural Engineers 2005 48/1 (101-108)
To properly simulate phosphorus (P) loading from agricultural
land to waters, changes in soil P status and processes affecting
soil P have to be described adequately. For practical reasons,
a model has to rely on data that are commonly available. In
this study, the P submodel of the ICECREAM model, based
on the CREAMS, GLEAMS, and EPIC models, was adapted to
simulate young acidic soils, which prevail in Finland. These
soils have a high P sorption capacity, plenty of inorganic P in a
non-reactive apatitic form, and the organic matter content (Or ) in
the plow layer is commonly about 5%. The model was modified
mainly on the basis of 12 long-term fertilization experiments and
tested on three other soils. The P pools considered were labile
P (P il ), active inorganic P (Pia ), stable inorganic P (P is ), fresh
organic P (Pof ), and more stable organic P (Poh ). The major
model modifications made were: (1) initialization of Pil from the
Finnish soil test results (ammonium acetate extractable P, PAAC );
(2) initialization of Pia and Pis from Pil , assuming equilibrium;
(3) revision of the P availability factor (Fl ), which regulates the
flow between Pil and Pia ; and (4) calculation of the initial values
of Poh from soil organic carbon content. These modifications
aimed to improve simulation of Pil on the basis of data obtained
from soil testing. Proper simulation of changes in Pil , reflected
by the soil test P (P AAC ), is critical since it regulates the level of
dissolved P in runoff water. After the modifications, the model
was able to predict changes in PAAC at annual P application rates
of 0 and 30 kg ha-1 in cereal cropping, but could not fully cope
with a large surplus of P resulting from an annual rate of 60 kg P
ha-1 . В© 2005 American Society of Agricultural Engineers.
1731 Carbaryl, 2,4-D, and Triclopyr adsorption in thatchsoil ecosystems
Raturi S., Islam K.R., Caroll M.J. and Hill R.L. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes 2005 40/5 (697-710)
Thatch development in intensively managed turf sites may cause
environmental concerns for greater sorption or leaching of applied chemicals in terrestrial ecosystems. To determine the ad-
sorption potential of Carbaryl (1-Napthyl N-methylcarbamate),
2,4-D (2,4-dichloro-phenoxyacetic acid), and Triclopyr (3,5,6trichloro-2-pyridinyloxyacetic acid) in turf ecosystems, composite thatch and underlying soil samples from three- and sixyear-old stands of cool-season Southshore creeping bentgrass
(Agrostis palustris Huds.) and warm-season Meyer zoysiagrass
(Zoysiajaponica Steud.) were collected. The samples were processed and analyzed for total organic carbon (COrg ); extractable
(CExt ), humic (CHA ) and fulvic acid (C FA ); anthrone reactive
nonhumic carbon (ARC) fractions; and C HA and CFA associated
iron (Fe) contents. Pesticide adsorption capacity (Kf ) and intensity (1/n), organic carbon partition coefficient (KOC ) and Gibbs
free energy change ( G) were calculated for thatch materials and
the underlying soils using a modified batch/flow technique. Both
bentgrass (BT) and zoysiagrass thatch (ZT) contained a greater
concentration of CExt CFA , CHA , and ARC than the respective
soils (BS and ZS). The CExt , CFA , CHA , and ARC concentration
was higher in BT compared with ZT. The BT contained a greater
concentration of bound Fe in both CFA and C HA fractions than
in BS, whereas ZT had more bound Fe in C HA fraction than in
ZS. On average, the BT had a greater concentration of bound
Fe in CExt , CFA , and CHA fractions than in the ZT. Among the
pesticides, Carbaryl had higher K f and 1/n values than 2,4-D
and Triclopyr for both thatch and soil. Although the KOC and
G values of Carbaryl were higher in both BT and ZT than
in the underlying soils, the KOC and G values of 2,4-D were
significantly higher in BS and ZS than in the overlying thatch
materials. The 2,4-D and Triclopyr had higher leaching indices
(LI) than Carbaryl for both BT and ZT materials than the respective soils. The Carbaryl, however, had a higher LI for soils
than for thatch materials. Averaged across thatch materials and
soils, COrg accounted for 96, 85, and 84% variations in Carbaryl,
2,4-D, and Triclopyr adsorption, respectively. Among the COrg
fractions, lignin followed by CFA and CHA accounted for greater
adsorption of pesticides, especially Carbaryl. The concentration
of CHA and CFA bound Fe did not correlate with Kf and 1/n values
of pesticides. Copyright В© Taylor & Francis Inc.
1732 Sorption of three tetracyclines by several soils: Assessing the role of pH and cation exchange
Sassman S.A. and Lee L.S. Environmental Science and Technology 2005 39/19 (7452-7459)
Tetracyclines (TCs) are widely used in veterinary medicine for
treatment and prevention of disease and are present in animal
waste products. Detection of TCs in soil, sediments, and water,
and the growing concern of their potentially adverse effect on
natural ecosystems have resulted in a need to understand their
behavior in aqueous soil systems. TCs have multiple ionizable functional groups such that at environmentally relevant pH
values, they may exist as a cation (+00), zwitterion (+-0), or a net
negatively charged ion (+--), which complicates predicting their
sorption, availability, and transport. We investigated the sorption
of oxytetracycline (DTC), tetracycline (TC), and chlortetracycline (CTC) by several soils varying in pH, clay amount and
type, cation exchange capacity (CEC), anion exchange capacity
(AEC), and soil organic carbon in 0.01 N CaCl2 , 0.001 N CaCl2 ,
and 0.01 N KCl. All three TCs are highly sorbed, especially
in acidic and high clay soils. When normalized to CEC, sorption tends to decrease with increasing pH. A sorption model in
which species-specific sorption coefficients normalized to pH+-0
+-dependent CEC (K+00
d , Kd , and K d ) and weighted by the pHdependent fraction of each species fit the data well across all soils
except for a soil rich in gibbsite and high in AEC. Resulting K+00
d
values were more than an order of magnitude larger than values
+-0
+-+00
for either Kd and Kd values such that Kd alone described
most of the sorption observed as a function of pH for eight soils
that varied in their mineralogy and pH (pH ranged from 4 to 8).
В© 2005 American Chemical Society.
1733 Transformation of carbon tetrachloride by thiol reductants in the presence of quinone compounds
Doong R.- A. and Chiang H.- C. Environmental Science and
Technology 2005 39/19 (7460-7468)
Quinones are present in trace amounts in natural organic matter.
The addition of thiol compounds to quinones produces reactive
electron-transfer species that may be important for the trans-
SOILS
formation of chlorinated hydrocarbons under sulfate-reducing
conditions. This study systematically investigated the transformation of carbon tetrachloride (CCl4 ) in homogeneous aqueous
solutions containing quinones as electron-transfer mediators and
thiol compounds as bulk reductants. The thiol compounds, including sodium hydrosulfide (NaHS) and cysteine, were found
to effectively transform CCl4 . The transformation of CCl4 followed pseudofirst-order kinetics, and the pseudo-first-order rate
constants (kobs ) were (3.24 0.46) 10-7 and 1.04 10-7 s-1 ,
respectively, when solutions contained NaHS and cysteine alone.
Addition of quinone compounds, including anthraquinone-2,6disulfonate (AQDS), benzoquinone (BQ), juglone (JQ), naphthoquinone (NQ), lawsone (LQ), and menadione (MQ), increased
the transformation rate and efficiency of CCl4 . The k 0bs values
for CCl4 transformation in the presence of quinones were 2.671 times higher than those for the thiol compounds alone. The
enhancement efficiency followed the order JQ > NQ > BQ
AQDS > LQ > MQ. Spectroscopic studies indicated that
the quinone compounds generated various active electron-transfer mediators to transfer electrons from the bulk reductants to
CCl4 . BQ and NQ produced mercaptoquinones as active redox
mediators that significantly enhanced the transformation rate of
CCl 4 in the presence of NaHS. The addition of thiol reductants produced large amounts of AQDS semiquinone radical as
the electron shuttle. In addition, MQ and LQ were reduced by
NaHS to give hydroquinone, which slightly enhanced the transformation efficiency of CCI4. These results clearly indicate that
the enhanced efficiency of quinones for the transformation of
chlorinated hydrocarbons is specifically related to the produced
reactive species. Mercaptoquinone is a more active mediator than
either semiquinone or hydroquinone for transferring electrons in
a reducing environment containing thiol reductants. В© 2005
American Chemical Society.
1734 Fate and transport of monoterpenes through soils.
Part I. Prediction of temperature dependent soil fate model
input-parameters
Van Roon A., Parsons J.R., Te Kloeze A.- M. and Govers H.A.J.
Chemosphere 2005 61/5 (599-609)
Monoterpenes are C10HnOn compounds of natural origin and
are potentially environmentally safe substitutes for traditional
pesticides. Still, an assessment of their environmental behaviour
is required. As a first step in a theoretical study focussing on
monoterpenes applied as pesticides to terrestrial environments,
soil fate model input-parameters were determined for 20 monoterpenes with widely different structural characteristics. Inputparameters are the water solubility (SW ), vapour pressure (P),
n-octanol-water partition coefficient (KOW ), atmospheric air and
bulk water diffusion coefficients (DAair and DWwater), first order biodegradation rate constants (k), and their temperature dependence. Values for these parameters were estimated or taken
from previous experimental work. The quality of the estimations
was discussed by focussing on their statistics and by comparison with available experimental data. From these properties,
the air-water partition coefficient (KAW , HenryвЂ™s Law constant),
the interface-water partition coefficient (KIW ) and the organic
matter-water partition coefficient (KOM ) could be estimated with
varying levels of accuracy. In general, little experimental data
turned out to be available on biodegradation rate constants and
on the temperature dependence of physico-chemical parameters.
В© 2005 Elsevier Ltd. All rights reserved.
1735 Effect of dissolved organic matter on copper-zinc competitive adsorption by a sandy soil at different pH values
Mesquita M.E. and Carranca C. Environmental Technology 2005
26/9 (1065-1072)
The effect of dissolved organic carbon from sewage sludge on
copper and zinc adsorption and interaction on samples from the
surface layer (0 - 10 cm) of a sandy soil (Gleyic Podzol) were
studied at two pH levels (4 and 7). This soil presented acidification hazards and sewage sludge with a high content of Cu
and Zn was used as a fertilizer. Soil samples were treated by
solutions of Cu and Zn as nitrate salts with concentration levels
up to 30 mg l-1 in a Ca(NO3 )2 background at a constant level
(180 mg l-1 ) of dissolved organic carbon (DOC). Copper and
zinc sorption capacity decreased in the presence of DOC. As the
pH increased, the decrease in Cu adsorption due to interaction
331
with DOC was more obvious. Conversely, without addition of
DOC, Cu and Zn adsorption increased with pH. More Cu than
Zn was adsorbed. Soil sorption of these cations was described by
equilibrium isotherms that fitted both Langmuir and Freundlich
type equations, presenting however a better fit to the Freundlich
equation (R2 >98%). Adsorption dependence on DOC was more
noticeable at pH 7. В© Selper Ltd., 2005.
1736 Tylosin sorption to silty clay loam soils, swine manure,
and sand
Clay S.A., Liu Z., Thaler R. and Kennouche H. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes 2005 40/6 (841-850)
The objectives of this study were to assess sorption and desorption of tylosin, a macrolide antimicrobial chemical used in swine,
cattle, and poultry production, in three silty clay loam soils of
South Dakota and compare soil sorption to sand and manure
sorption. The silty clay loam soils, from a toposequence in eastern South Dakota, standardized sand samples, and swine manure
were used in 24-h batch sorption studies with tylosin concentrations ranging from 25 to 232 mole/L. Desorption from soil was
conducted over a four-day period. Partition coefficients, based
on the Freundlich isotherm (Kf ) or Kd values, were calculated.
Kf values for the silty clay loams were similar, not influenced
by landscape position, and averaged 1350 with isotherm slopes
ranging from 0.85 to 0.93. Kf values for sand were dependent on
solution/sand ratios and pH, ranging from 1.4 to 25.1. Kd values
of manure were dependent on the solution type and ranged from
840 L/kg with urine to about 175 L/kg when sorbed from water.
Desorption of tylosin from each soil over the four-day period was
<0.2% of the amount added. The soilsвЂ™ high Kf values and low
desorption amounts suggest that once tylosin is in these soils,
leaching to lower depths may not occur. However, this does not
preclude runoff with soil eroded particles. If tylosin reaches a
sand aquifer, through bypass flow or other mechanism(s), movement in the aquifer most likely would occur. Copyright В© Taylor
& Francis Inc.
1737 Recent atmospheric Pb deposition at a rural site in
southern Germany assessed using a peat core and snowpack,
and comparison with other archives
Le Roux G., Aubert D., Stille P. et al. Atmospheric Environment
2005 39/36 (6790-6801)
In a peat bog from Black Forest, Southern Germany, the rate of
atmospheric Pb accumulation was quantified using a peat core
dated by 210 Pb and 14 C. The most recent Pb accumulation rate
(2.5 mg m-2 y-1 ) is similar to that obtained from a snowpack on
the bog surface, which was sampled during the winter 2002 (1 to
4 mg m-2 y -1 ). The Pb accumulation rates recorded by the peat
during the last 25 yr are also in agreement with published values
of direct atmospheric fluxes in Black Forest. These values are
50 to 200 times greater than the "natural" average background
rate of atmospheric Pb accumulation (20 g m-2 y-1 ) obtained
using peat samples from the same bog dating from 3300 to 1300
cal. yr B.C. The isotopic composition of Pb was measured in
both the modern and ancient peat samples as well as in the snow
samples, and clearly shows that recent inputs are dominated by
anthropogenic Pb. The chronology and isotopic composition
of atmospheric Pb accumulation recorded by the peat from the
Black Forest is similar to the chronologies reported earlier using
peat cores from various peat bogs as well as herbarium samples of
Sphagnum and point to a common Pb source to the region for the
past 150 years. In contrast, Pb contamination occurring before
1850 in southwestern Germany, differs from the record published for Switzerland mainly due to the mining activity in Black
Forest. Taken together, the results show that peat cores from
ombrotrophic bogs can yield accurate records of atmospheric
Pb deposition, provided that the cores are carefully collected,
handled, prepared, and analysed using appropriate methods. В©
2005 Elsevier Ltd. All rights reserved.
1738 Facilitation of pentachlorophenol degradation in the
rhizosphere of ryegrass (Lolium perenne L.)
He Y., Xu J., Tang C. and Wu Y. Soil Biology and Biochemistry
2005 37/11 (2017-2024)
The phytoremediation of xenobiotics depends upon plant-mi-
332
SOILS
crobe interactions in the rhizosphere, but the extent and intensity of these effects are currently unknown. To investigate
rhizosphere effects on the biodegradation of xenobiotics, a glasshouse experiment was conducted using a specially designed rhizobox where ryegrass seedlings were grown for 53 days in a
soil spiked with pentachlorophenol (PCP) at concentrations of
8.7 0.5 and 18 0.5 mg kg-1 soil. The soil in the rhizobox was
divided into six separate compartments at various distances from
the root surface. Changes in PCP concentrations with increasing
distance from the root compartment of the rhizobox were then
assessed. The largest and most rapid loss of PCP in planted soil
was at 3 mm from the root zone where total PCP decreased to 0.20
and 0.65 mg kg-1 , respectively with the two PCP treatments. The
degradation gradient followed the order: near-rhizosphere>root
compartment>far- rhizosphere soil zones for both concentrations
where ryegrass was grown. In contrast, there was no difference
in PCP concentration with distance in the unplanted soil. The increases in both soil microbial biomass carbon and the activities of
soil urease and phosphatase were accompanied by the enhanced
degradation of PCP, which was higher in the near-rhizosphere
than far-rhizosphere soil. The results suggest that the effect of
root proximity is important in the degradation of xenobiotics such
as PCP in soil. В© 2005 Elsevier Ltd. All rights reserved.
1741 Quantification and bioavailability of scyllo-inositol
hexakisphosphate in pasture soils
Turner B.L., Mahieu N., Condron L.M. and Chen C.R. Soil Biology and Biochemistry 2005 37/11 (2155-2158)
The recent identification of scyllo-inositol hexakisphosphate in
alkaline soil extracts by solution 31 P NMR spectroscopy allowed
us to investigate this compound in soils by re-analyzing spectra from two previously published studies. Concentrations of
scyllo-inositol hexakisphosphate in 29 temperate pasture soils
from England and Wales ranged between 11 and 130 mg P kg-1
soil and accounted for between 4 and 15% of the soil organic
phosphorus. The ratio of scyllo-inositol hexakisphosphate to
myo-inositol hexakisphosphate ranged between 0.29 and 0.79.
In a 10 month pot experiment with six grassland soils from New
Zealand, growth of pine seedlings (Pinus radiata D. Don) decreased scyllo-inositol hexakisphosphate concentrations by between 10 and 46%. Growth of ryegrass (Lolium perenne L.)
decreased scyllo-inositol hexakisphosphate in three low-nutrient soils by 5-21%, but increased it in three other soils by 1116%. We conclude that scyllo-inositol hexakisphosphate is an
important component of soil organic phosphorus with potential
ecological significance. В© 2005 Elsevier Ltd. All rights reserved.
1739 Organic acid behaviour in a calcareous soil implications for rhizosphere nutrient cycling
StrВЁom L., Owen A.G., Godbold D.L. and Jones D.L. Soil Biology
and Biochemistry 2005 37/11 (2046-2054)
Calcareous soils are frequently characterized by the low bioavailability of plant nutrients. Consequently, many vascular plant
species are unable to successfully colonize calcareous sites and
the floristic composition of calcareous and acid silicate soils has
been shown to differ markedly. The root exudation of oxalate
and citrate has been suggested to play a pivotal role in same
nutrient acquisition mechanisms operating in calcareous soils.
The aim of this study was therefore to investigate the nutrient
extraction efficiency of three individual organic acids commonly
identified in root exudates, i.e. citric, malic and oxalic acid.
Our results clearly demonstrate the context dependent nature of
nutrient release by organic acids. The degree of P extraction
was highly dependent on which organic acid was added, their
concentration and pH, and their contact time with the soil. P is
generally more efficiently extracted by organic acids at a high
pH and follows the series oxalate>citrate>malate. The opposite
relationship between pH and extraction efficiency was apparent
for most other cations examined (e.g. Zn, Fe), which are more
efficiently extracted by organic acids at low pH. A serious constraint to the ecological importance of organic acid exudation in
response to P deficiency is, however, their very low P mobilization efficiency. For every mol of soil P mobilized, 1000 mol
of organic acid has to be added. It can, however, be speculated
that in a calcareous soil with extremely low P concentrations it is
still beneficial to the plants to exude organic acids in spite of the
seemingly high costs in terms of carbon. В© 2005 Elsevier Ltd.
All rights reserved.
1742 Mineralisation of C and N from root, stem and leaf
residues in soil and role of their biochemical quality
Abiven S., Recous S., Reyes V. and Oliver R. Biology and Fertility
of Soils 2005 42/2 (119-128)
The influence of biochemical characteristics of 15 crop residues
on C and N mineralisation in soil was investigated by following
the decomposition of roots, stems and leaves of four subtropical
species and one temperate species buried into the soil. The
C, N and polyphenols contents were measured in different biochemical pools obtained from residues of the different organs.
The mineralisation of root C was significantly lower than that of
leaves and stems. Chemical analysis showed a higher polyphenol
content in the leaves and a higher ligninlike content in the roots.
Carbon and N mineralisation were simulated with the STICS decomposition submodel and tested against the data set. The model
predicted leaf and stem C mineralisation for all five species fairly
accurately, but failed to predict root C mineralisation, indirectly
revealing the more complex composition of the root tissue. The
results showed the interest of separately considering the different
plant parts when studying plant residue decomposition and the
need to develop other methods of residue quality characterisation
to improve the prediction of residue decomposition.
1740 Availability of CO2 as a factor affecting the rate of
nitrification in soil
Azam F., Gill S. and Farooq S. Soil Biology and Biochemistry
2005 37/11 (2141-2144)
A laboratory incubation experiment was conducted to demonstrate that reduced availability of CO2 in soil may be an important factor limiting nitrification. Soil samples were incubated at
30 2В°C for 20 days using vessels with or without the arrangement for trapping CO2 in sodium hydroxide. This arrangement
led to a decrease of ca. 96% in the CO2 concentration of the headspace, with a range of 95.7-97.5 at different sampling intervals.
In the absence of trapping arrangement, CO 2 concentration of
the headspace varied from 580 to 859 ppm, i.e. 62-140% higher
than that of the outside atmosphere (358 ppm). The nitrification
process was significantly retarded under conditions of reduced
CO2 concentration; reduction varied from 8 to 62% at different
incubation intervals. The results of the study led to the inference that decreased availability of CO2 in closed vessels (with
arrangement for trapping CO2 ) will have a significant bearing on
the process of nitrification and hence on the overall dynamics of
N transformations. В© 2005 Elsevier Ltd. All rights reserved.
1743 Availability of urea to autotrophic ammonia-oxidizing
bacteria as related to the fate of 14 C- and 15 N-labeled urea
added to soil
Marsh K.L., Sims G.K. and Mulvaney R.L. Biology and Fertility
of Soils 2005 42/2 (137-145)
Nitrate has been found to accumulate more rapidly in soils fertilized with urea than with inorganic sources of NH4 + , despite the
fact that nitrification must be preceded by hydrolytic decomposition. For acidic conditions, this finding has been attributed to
limited uptake of NH 4 + by ammonium-oxidizing bacteria (also
reported herein), suggesting an advantage for direct utilization of
a nonionizable N substrate such as urea. If the same advantage
applies to urea-C, nitrification of urea-N would also be promoted
in neutral or alkaline soils, as reported in numerous studies. To
ascertain whether urea-C can be utilized directly by nitrifying
organisms, NO2 - production was measured for Nitrosomonas
europaea and Nitrosospira sp. NPAV in minimal media with urea
as the sole source of either C or C and N. Nitrite accumulated
only with the latter organism, in which case nearly quantitative
recovery was observed for N added as NH 4 + and/or urea. In a
subsequent study, recovery of 14 C and 15 N in gaseous, extractable, and hydrolyzable forms was determined after incubation
with labeled urea for up to 29 days, by using two soils that differed markedly in physiochemical properties affecting nutrient
availability. Results obtained in correlating 14 C incorporation in
the amino acid fraction with 15 N accumulation as NO3 - were
consistent with the stoichiometry that would be expected if C
fixation were driven by autotrophic nitrification. Our findings
demonstrate unequivocally that urea is utilized as a source of
SOILS
C and N by nitrifying microorganisms, which may account for
rapid nitrification of urea-N in soils.
1744 Effects of previous elemental sulfur applications on
oxidation of additional applied elemental sulfur in soils
Li S., Lin B. and Zhou W. Biology and Fertility of Soils 2005
42/2 (146-152)
Oxidation of elemental sulfur (S0 ) in 20 Chinese agricultural
soils was tested and the effects of previous S0 applications on
the oxidation of additional applied S0 in selected soils were investigated using laboratory, greenhouse, and field experiments.
Results showed that sulfur oxidative capacities presented great
variability among 20 tested soils, with a coefficient of variation
of 92.4%. There were no significant relationships between S0
oxidation and physical and chemical properties of the selected
soil. Previous S0 amendment significantly increased the oxidation rate of additional applied S0 . These stimulatory effects after
the first applications of S0 were greater than those after two
applications. The percent increase in S0 oxidation rate due to S0
pretreatment was negatively correlated with the oxidation capacities of soils before S0 pretreatments. The significant reduction
of sulfur oxidation in autoclaved soils and significant increase
in S0 oxidation after inoculation with S0 -treated soil suspension
demonstrated that microbial oxidation was mainly responsible
for the enhancement of soil oxidation ability after previous S0
amendments.
1745 The relation between the content of organic phosphorus and latitude in Northeast China phaeozem
Yu W., Zhao S., Zhang L. et al. Biology and Fertility of Soils
2005 42/2 (159-162)
Top phaeozem samples were collected from Nenjiang County
(in Heilongjiang province) to Changtu County (in Liaoning
province) in Northeast China every 6 km by using global positioning system (GPS) and analyzed for their content of organic
C, total N, total P, organic P, and the organic to inorganic P (P
o /Pi ) ratio. The content of organic P was significantly correlated
with organic C and total N contents (P<0.01). The contents of
organic P and total P and the Po /Pi ratio were significantly correlated with latitude (P<0.01), with r 2 coefficient of 0.59, 0.46, and
0.36, respectively. Since inorganic P content was not correlated
with latitude (r 2 =0.07) and the contents of organic P and total P
were significantly correlated (P<0.01, r 2 =0.70), it is reasonable
to hypothesize that organic P can play an important role in the
spatial differentiation of total P and the Po /Pi ratio. Probably, the
causes of these spatial differentiations were the effects of climate
and reclamation variations along the North-South transect.
1746 Base-cation cycling by individual tree species in oldgrowth forests of Upper Michigan, USA
Fujinuma R., Bockheim J. and Balster N. Biogeochemistry 2005
74/3 (357-376)
The influence of individual tree species on base-cation (Ca, Mg,
K, Na) distribution and cycling was examined in sugar maple
(Acer saccharum Marsh.), basswood (Tilia americana L.), and
hemlock (Tsuga canadensis L.) in old-growth northern hardwood
- hemlock forests on a sandy, mixed, frigid, Typic Haplorthod
over two growing seasons in northwestern Michigan. Base cations in biomass, forest floor, and mineral soil (0-15 cm and
15-40 cm) pools were estimated for five replicated trees of each
species; measured fluxes included bulk precipitation, throughfall, stemflow, litterfall, forest-floor leachate, mineralization +
weathering, shallow-soil leachate, and deep-soil leachate. The
three species differed in where base cations had accumulated
within the single-tree ecosystems. Within these three single-tree
ecosystems, the greatest quantity of base cations in woody biomass was found in sugar maple, whereas hemlock and basswood
displayed the greatest amount in the upper 40 cm of mineral
soil. Base-cation pools were ranked: sugar maple > basswood,
hemlock in woody biomass; sugar maple, basswood > hemlock
in foliage; hemlock > sugar maple, basswood in the forest floor,
and basswood > sugar maple, hemlock in the mineral soil. Basecation fluxes in throughfall, stemflow, the forest-floor leachate,
and the deep-soil leachate (2000 only) were ranked: basswood
> sugar maple > hemlock. Our measurements suggest that
species-related differences in nutrient cycling are sufficient to
produce significant differences in base-cation contents of the soil
333
over short time intervals (<65 years). Moreover, these speciesmediated differences may be important controls over the spatial
pattern and edaphic processes of northern hardwood-hemlock
ecosystems in the upper Great Lakes region. В© Springer 2005.
1747 Effect of water content on kinetics of volatile organic
compounds mass transfer between gas and aqueous phases
during gas transport in unsaturated sand
Kim H., Annable M.D. and Rao P.S.C. Soil Science 2005 170/9
(680-691)
The effect of changing water content on the air-water mass transfer kinetics of volatile organic compounds (VOCs) during gas
transport in unsaturated sand was investigated. The kinetics of
VOC adsorption at the air-water interface from the gas phase
was explored using n-decane, whereas methylene chloride was
used to examine the effect of air-water partitioning. Methane
was used as the nonreactive tracer in VOC transport experiments
conducted using a sand column installed in a gas chromatography
system. The longitudinal dispersion of methane, estimated from
methane breakthrough curve (BTC), was found to be constant in
the water content range (0.07 to 0.18) examined in this study at a
constant pore-gas velocity ( g ), whereas an inverse proportionality between the longitudinal dispersion and g was observed.
The BTCs for methane and n-decane, measured at constant g ,
were fairly symmetric, indicating that both gas diffusion and
adsorption at air-water interfaces do not produce nonequilibrium
transport. The shape of the methylene chloride BTC was gradually distorted at a constant g as water content increased. Fitting methylene chloride BTCs with a modified two-region model
showed that the water partitioning becomes more rate-limited as
water content increases. The overall mass transfer coefficient for
water partitioning of methylene chloride was found to be a direct
function of specific air-water interfacial area. Copyright В© 2005
by Lippincott Williams & Wilkins, Inc.
1748 Phosphate sorption by Thai red oxisols and red ultisols
Trakoonyingcharoen P., Kheoruenromne I., Suddhiprakarn A.
and Gilkes R.J. Soil Science 2005 170/9 (716-725)
Phosphate sorption characteristics of 28 samples of red Oxisols and red Ultisols from agricultural areas of Thailand were
described by using Langmuir and Freundlich equations. The
soils were three Typic Kandiudults, a Typic Paleustult, a Typic
Kandiustult, a Typic Kandiustox, three Rhodic Kandiustox, two
Rhodic Kandiudox, two Typic Kandiudox, and a Kandiudalfic
Eutrudox. Values of Langmuir P maximum (Xm ) ranged from
18 to 1111 mg kg-1 soil and the Freundlich k coefficient varied
between 9 and 652 mg kg -1 . Many soil properties were closely
correlated with these measures of P sorption capacity including total titanium, goethite, total iron, amorphous aluminum,
and specific surface area. Goethite, microcrystalline kaolin, and
amorphous forms of Fe and Al oxides were major contributors
to P sorption by these soils. The Freundlich B coefficient, which
is a measure of P bonding energy, was weakly related to clay
content but there were no close relationships between the equivalent Langmuir b coefficient and soil properties. Soil pH in
1 M NaF (pH 8.0) was highly predictive of P sorption and may
therefore be used as a quick economical field test for evaluating P
fertilizer requirement. Copyright В© 2005 by Lippincott Williams
& Wilkins.
1749 Low-molecular-weight organic acid exudation of rape
(Brassica campestris) roots in cesium-contaminated soils
Po N.C., Wang M.K., Jeng J.W. and Chiu C.- Y. Soil Science
2005 170/9 (726-733)
Cesium is an emission element from nuclear energy generation
easily transferred to food chain. More evidence has been found
that Brassica crops take up pollutants from soils. The objective of
this study was to investigate the correlation between soil bioavailability of cesium and low-molecular-weight organic acids (LMWOAs) in rape (Brassica campestris) root exudates. Longtan
(LT) red (Typic Hapladox) and Kuanshan (KS) iron-rich calcareous soils (Typic Paleudalf) were collected for this study. The pot
experiments of rape were conducted with cesium-amended soils
and plants grown in the soils (4 weeks). Cesium concentration
in shoots and roots correlated well with Cs concentration in the
amended soils. Within the amended range of 50 to 300 mg Cs
kg -1 soil, Cs did not inhibit rape growth. The bioaccumulation
334
SOILS
ratio ([Cs]root /[Cs]soil ] or [Cs]shoot /[Cs] soil ) for Cs in shoots of pot
grown plants ranged between 9 and 31 and showed significant
differences (P < 0.05). Plant roots can exude LMWOAs, which
are important components in root exudation. The total amounts
of volatile and nonvolatile LMWOAs in all Cs-amended soils
were higher than those in nonamended soils. Meanwhile, the
LMWOA concentrations of the rape root exudates showed good
correlation with Cs concentrations in the applied range of 50 to
300 mg Cs kg-1 soil. Copyright В© 2005 by Lippincott Williams
& Wilkins.
1750 Temperature effects on iron reduction in a hydric soil
Rabenhorst M.C. and Castenson K.L. Soil Science 2005 170/9
(734-742)
For soils to be considered hydric, they must demonstrate both
saturation and anaerobic conditions in the upper part of the soil.
Although several technologies are available for monitoring of
soil water tables, documentation of reducing conditions is more
problematic. This has led to recent interest in the use of IRIS
(indicator of reduction in soils) tubes. IRIS tubes are lengths
of PVC pipe coated with ferrihydrite paint, which are inserted
into the soil to document reducing conditions. Observations from
preliminary studies led us to postulate soil temperature will affect
the degree and rate of reduction and removal of ferrihydrite from
the IRIS tubes. To quantify the impact of soil temperature on
ferrihydrite reduction and removal from IRIS tubes, a time series
experiment was designed such that IRIS tubes were placed into
a hydric soil for time periods ranging from 7 to 28 days, between
February and June, 2004. Water tables were monitored daily,
Eh was measured at depths of 10, 20, 30, 40 and 50, cm on a
weekly basis, and soil temperature was recorded every 4 hours.
Removal of ferrihydrite from IRIS tubes was not constant during
periods of anaerobiosis and was related to soil temperature. At
temperatures below 2В°C, there was essentially no measurable ferrihydrite reduction, even though soil redox potentials fell within
the Fe(II) stability field. As soil temperatures increased between
2 and 8В°C, the quantity of ferrihydrite reduction increased with
time. At soil temperatures between 8 and 20В°C, substantial (35%
to 45%) ferrihydrite paint was reduced and removed from IRIS
tubes within 7 days. For a given temperature, there was greater
reduction of ferrihydrite in zones closer to the soil surface, presumably due to higher amounts of oxidizable organic matter in
near surface horizons. Copyright В© 2005 by Lippincott Williams
& Wilkins.
1751 Mobility of natural radionuclides and selected major
and trace elements along a soil toposequence in the Central
Spanish Pyrenees
Navas A., Machn J. and Soto J. Soil Science 2005 170/9 (743757)
Natural gamma-emitting radionuclides (238 U, 226 Ra, 232 Th, 210 Pb)
and selected major and trace elements (Ca, K, Mg, Na, Fe, Al,
Mn, Pb, Ba, Zn, Sr, Li, Co, Ni, Cu, Cr, Cd) were determined
in a soil toposequence along a mountain slope of the Tertiary
Flysch landscapes in the Central Spanish Pyrenees. A variety
of basic properties were also measured from the soil profiles.
Mean radioisotope activities (Bq kg -1 ) range from 22 to 33 for
238 U; 25 to 32 for 226 Ra; 23 to 33 for 210 Pb, and 37 to 46 for
232 Th. The radionuclides showed different patterns in their depth
distribution, thus U and Pb had largest differences in concentrations down the soil profiles, whereas 226 Ra and 232 Th exhibited
uniform depth distributions. 238 U was depleted in all upper soil
layers and enriched in deeper layers. Pb exhibits very different
depth profiles along the soil toposequence and accumulated at
upper layers in three sites. 238 U/226 Ra activity ratios indicate
disequilibrium in the 238 U decay chain and reflect the leaching
of 238 U in contrast with the lack of mobility of 226 Ra. The
values of 232 Th/226 Ra indicate that the initial proportionality in
the 238 U and 232 Th decay chains has not been maintained in
this toposequence. The relationships between soil properties and
gamma-emitting radionuclides suggested the association of 226 Ra
and 232 Th with Fe and Mn oxides. Al, Ca, Fe, and K were the
most abundant elements, followed by Mn, Ba, Pb, Sr, Li, and Zn,
whereas Co, Cu, Ni, and Cr are as trace elements and Cd was
not detected. Correlations between elements suggest association
with carbonates (Ca, Sr), silicates and clay minerals (Al, K, Na)
and with Fe and Mn oxides (Cr, Cu, Ni, Co, Zn). Along the
soil toposequence, Ca, Sr, Mg and Na, K, Al increase at the
bottom slope positions, due to highest carbonate contents and
abundance of finer soil fractions (clay and silt), respectively. Fe
and Mn decrease at the bottom slope because highest contents of
Fe and Mn oxides are at upper slope positions. This research is
of interest to describe the geochemical cycling of elements in the
environment and to assess the processes that affect their mobility
in the ecosystems. Copyright В© 2005 by Lippincott Williams &
Wilkins.
1752 Modeling the effects of gas phase CO2 intrusion on the
biogeochemistry of variably saturated soils
Altevogt A.S. and Jaffe P.R. Water Resources Research 2005 41/9
(1-9)
[1] The transport of gas phase carbon dioxide through unsaturated
soils has the potential to significantly alter the soil biogeochemistry. Leakage of CO2 from deep reservoirs, either naturally
occurring or anthropogenically emplaced, may displace oxygen
in the soil gas and hence radically alter the redox conditions
of a soil. Furthermore, the formation of carbonic acid in the
aqueous phase will alter the pH of the soil system. A two-dimensional numerical model has been developed to explore the effects
of gaseous CO2 leakage on the biogeochemistry of a variably
saturated porous media. The model describes the sequential
degradation of organic carbon by microorganisms using a series
of terminal electron acceptors. Gas phase CO2 intrusion results
in changes in redox conditions and pH of the soil water, both
of which lead to alteration of the biogeochemistry of the soil.
Alteration of the biogeochemical profile of a representative field
site is explored with the numerical model. Copyright 2005 by
the American Geophysical Union.
1753 Selenium distribution in topsoils and plants of a semiarid Mediterranean environment
Moreno Rodriguez M.J., Cala Rivero V. and JimВґenez Ballesta R.
Environmental Geochemistry and Health 2005 27/5-6 (513-519)
Selenium was determined from 25 topsoils and 25 plants in the
semi-arid Central Spain where large extents of soils are developed
on evaporitic materials. Some species of vegetation associated
with them are of the genera Astragalus, Salsola, Mercurialis,
Phlomis, Thymus and Atriplex. Total selenium in soils was determined and its bioavailability assessed by chemical sequential
fractionation. Se content in soils was adequate (in the range
0.17-0.39 mg kg-1 ) or large (in the range 0.50-4.38 mg kg-1 ) and
appeared in highly and/or potentially available forms. Several
plant species showed high Se levels (in the range 5-14.3 mg
kg-1 ), which can be a potential risk of toxicity to animals. Data
obtained from the study area can be used as a guide to the range
of values in soils and plants of the European Mediterranean area
that are relatively unpolluted from industrial sources, allowing
comparison with more polluted areas. В© Springer 2005.
1754 Uranium accumulation of crop plants enhanced by
citric acid
Chang P., Kim K.- W., Yoshida S. and Kim S.- Y. Environmental
Geochemistry and Health 2005 27/5-6 (529-538)
Citric acid was applied to soil to enhance U accumulation in
four crop plants. While the highest enhanced U accumulation of
aboveground tissues (a.c. 2000 mg kg-1 dry weight) occurred
in the leaves of Indian mustard (Brassica juncea), the highest enhanced U accumulation of roots (a.c. 3500 mg kg-1 dry
weight) occurred in canola (Brassica napus var. napus). Uranium translocation among tissues of test plants is in the relation
of roots > shoots = leaves. The flowers of sunflower (Helianthus
annuus) contained similar or higher U concentrations than those
found in shoots, but concentrations in seeds are close to zero.
In conclusion, Indian mustard is recommended as a potential
species for phytoextraction for U-contaminated soil due to its
high U accumulation of aboveground biomass (a.c. 2200 g
per plant). There is no evidence that two types of soils cause a
significant difference of the enhanced U accumulation (p<0.05).
Results, however, indicate that additional citric acid may result
in downward U migration that may contaminate groundwater.
Speciation of U that is taken up by plants is also discussed in the
end. В© Springer 2005.
SOILS
222 Rn
activity concentration in soil gas at
1755 Variation of
a site in Sapporo, Japan
Fujiyoshi R., Kinoshita M. and Sawamura S. Environmental
Geochemistry and Health 2005 27/5-6 (539-547)
Several factors controlling the soil radon level in the present site
were found to be changing air-filled porosity caused by fluctuations in moisture content, differences between the atmospheric
and soil temperatures as well as volumetric 226 Ra content of the
soil. The radon activity increased significantly in early October,
especially at point 1, possibly as a result of a magnitude 8.0
earthquake which occurred on September 26, 2003, with epicenter located offshore near Tokachi, Hokkaido. В© Springer 2005.
1756 The impact of the hyperacid Ijen Crater Lake. Part I:
Concentrations of elements in crops and soil
Heikens A., Widianarko B., Dewi I.C. et al. Environmental
Geochemistry and Health 2005 27/5-6 (409-418)
In Asembagus (East Java, Indonesia) irrigation water is contaminated with effluent from the hyperacid Ijen Crater Lake resulting
in a low pH and high levels of various elements. As a first step
towards a risk assessment, locally produced food items (rice,
maize, cassava leaf, cassava root, peanuts) were collected and
concentrations of As, B, Ca, Cd, Co, Cu, Fe, Mg, Mn, Mo, Ni,
Pb, V, Zn were compared to samples from a reference area and
with literature values. Further, concentrations in rice were compared to total soil concentrations in paddy fields. Compared to
the reference area, food items produced in the contaminated area
had increased levels of Cd, Co, Ni and Mn in particular, while
levels of Mo were lower. In contrast, total soil concentrations
of Cd and Mn in particular have decreased whereas especially
Mo was increased. In combination with the observed soil acidification, it is likely that the bioavailable concentration of most
elements in the contaminated soil is higher (except for Mo) due to
an increased weathering rate and/or input via the contaminated
irrigation water. In terms of human health, concentrations in
foods were generally within normal literature values. However,
it was observed that essential elements (in particular Fe) known
for their inhibitory effects on e.g. Cd and Mn toxicity did not
accumulate in crops whereas Cd and Mn did. В© Springer 2005.
1757 Effect of sewage sludge or compost on the sorption and
distribution of copper and cadmium in soil
Vaca- Pauln R., Esteller- Alberich M.V., Lugo- De La Fuente
J. and Zavaleta- Mancera H.A. Waste Management 2006 26/1
(71-81)
The application of biosolids such as sewage sludge is a concern,
because of the potential release of toxic metals after decomposition of the organic matter. The effect of application of sewage
sludge (Sw) and compost (C) to the soil (S) on the Cu and Cd
sorption, distribution and the quality of the dissolved organic
matter (DOM) in the soil, was investigated under controlled conditions. Visible spectrophotometry, infrared spectroscopy, sorption isotherms (simple and competitive sorption systems), and
sequential extraction methods were used. The E4 /E6 ( at 465
and 665 nm) ratio and the infrared spectra (IR) of DOM showed
an aromatic behaviour in compost-soil (C-S); in contrast sewage
sludge-soil (Sw-S) showed an aliphatic behaviour. Application
of either Sw or C increased the Cu sorption capacity of soil.
The Cd sorption decreased only in soil with a competitive metal
system. The availability of Cu was low due to its occurrence
in the acid soluble fraction (F3). The Cu concentration varied
in accordance with the amounts of Cu added. The highest Cd
concentration was found in the exchangeable fraction (F2). The
Sw and C applications did not increase the Cd availability in the
soil. В© 2005 Elsevier Ltd. All rights reserved.
1758 Characterization of phosphorus in sub-alpine forest
and adjacent grassland soils by chemical extraction and phosphorus-31 nuclear magnetic resonance spectroscopy
Chiu C.- Y., Pai C.- W. and Yang K.- L. Pedobiologia 2005 49/6
(655-663)
We used chemical extraction methods and 31 P-nuclear magnetic
resonance (NMR) to investigate the effects of vegetation on the
amount and structural composition of phosphorous (P) in the
sub-alpine soils of central Taiwan. Chemical extraction methods
were used to measure inorganic P (Pi) and organic P (Po) in main
335
soil horizons. The soil P composition was assessed by
spectroscopy on alkaline EDTA-NaOH extracts. According to
the results of chemical extractions, the forest soil had a higher
amount of Pi than the grassland soil, which might be a result
of the mineralization of Po. 31 P-NMR spectra showed inorganic
orthophosphate (up to 67%) and orthophosphate monoesters (up
to 75%) as the major forms of P extracted in forest and grassland soils, respectively. Smaller proportions of orthophosphate
diesters and trace amounts of phosphonates and pyrophosphate
were found. With possible hydrolysis of P compounds during
chemical extraction and slight systemic error in the processes
of extraction with NMR, the results from NMR analysis are, in
general, consistent with those of chemical extraction. В© 2005
Elsevier GmbH. All rights reserved.
31 P-NMR
1759 Effects of different ground clearance on soil fertility of
Chinese fir stands (Chinese)
Xue L., Xiang W., He Y. et al. Chinese Journal of Applied
Ecology 2005 16/8 (1417-1421)
The study on the soil physical properties, nutrient contents,
microbial amounts and enzyme activities of clear cuttting and
controlled burning Chinese fir stands showed that in comparing with the control, soil non-capillary porosity of clear cutting
stand increased by 23%, whereas soil natural water capacity
and capillary moisture capacity decreased by 25%. In controlled
burning stand, soil bulk density increased by 10%, while soil noncapillary porosity, natural water capacity and capillary moisture
capacity decreased by 61%, 48% and 26%, respectively. The
contents of soil organic matter, total N, total P and total K in
clear cutting stand decreased by 14%, 14%, 35% and 22%, and
in controlled burning stand, they decreased by 37%, 37%, 47%
and 7%, respectively. Soil alkalized N and available K in clear
cutting stand increased by 24% and 31%, respectively, but soil
available P decreased by 15%. The contents of soil alkalized N,
available P and available K in controlled burning stand decreased
by 25%, 43% and 40%, respectively. In clear cutting stand, the
amounts of soil bacteria, fungi and actinomyces increased by 1.4,
11.3 and 0.8 times, respectively, but in controlled burning stand,
the amounts of soil bacteria decreased by 24%, while those of
soil fungi and actinomyces increased by 5.0 and 0.5 times, respectively. The activities of soil urease, catalase and cellulase
in clear cutting stand increased by 1.9, 1.6 and 2.1 times, and in
controlled burning land, they were 35%, 90% and 106% of the
control, respectively. Damp soil had higher contents of organic
matter, total N and total P, whereas porous soil was favorable for
the accumulation of alkalized N, available P and available K and
for the increase of soil urease activity. The amount of soil fungi
decreased with increasing soil capillary porosity. Aerated soil
was favorable for the increase of soil catalase activity.
1760 Spatial variability of nutrients in cultivated soils of
Xinhui District, Jiangmen City (Chinese)
Gan H. and Peng L. Chinese Journal of Applied Ecology 2005
16/8 (1437-1442)
Employing geostatistical methods and GIS technology, this paper studied the spatial distribution characteristics of pH, organic
matter, CEC, total nitrogen, available phosphorus and slowly
available potassium in cultivated soils of Xinhui District, Jiangmen City. All the test variables were normally or log normally
distributed. Semivariogram analysis showed that soil nutrients
were moderately spatially-dependent in a given spatial range,
except that soil total nitrogen was strongly spatially-dependent.
It was shown from Kriging analysis that soil pH and CEC was
the highest in the northeast, and soil organic matter content was
higher in the middle and northeast investigation region. The area
with 1.5-2.0 g kg-1 soil total nitrogen content accounted for 75.7
% of the investigated region, mainly distributed in the west and
east, that with >40 mg kg-1 soil available phosphorus content
was accounted for 48.7%, mainly distributed in the west and
northeast, and the area that slowly available potassium content
was 160-350 mg kg-1 accounted for 48.1%, mainly distributed in
the east, northeast and the middle.
1761 Relationships between red soil enzyme activity and
fertility (Chinese)
Xue D., Yao H., He Z. and Huang C. Chinese Journal of Applied
Ecology 2005 16/8 (1455-1458)
336
SOILS
Correlation and cluster analyses on the enzyme activities and
chemical-biological properties of eight red soils showed that soil
urease, invertase, phosphatase and catalase activities correlated
significantly with soil organic carbon, total nitrogen and total
phosphorous. Similar results of soil fertility evaluation were
obtained by using soil enzyme activities and by using soil chemical-biological properties, indicating that soil enzyme activity
could be used as an index of evaluating red soil fertility. The
enzyme activities of fresh soil were generally greater than those
of air-dried sample, and more closely correlated with soil fertility.
Organic matter
1762 Soil carbon stocks and changes in the Republic of
Ireland
Tomlinson R.W. Journal of Environmental Management 2005
76/1 (77-93)
The soil carbon (C) stock of the Republic of Ireland is estimated
to have been 2048 Mt in 1990 and 2021 Mt in 2000. Peat holds
around 53% of the soil C stock, but on 17% of the land area. The
C density of soils (t C ha-1 ) is mapped at 2 km 2 km resolution.
The greatest soil C densities occur where deep raised bogs are
the dominant soil; in these grid squares C density can reach 3000
t C ha-1 . Most of the loss of soil C between 1990 and 2000 - up
to 23 Mt C (1% of 1990 soil C stock) - was through industrial
peat extraction. The average annual change in soil C stocks from
1990 to 2000 due to land use change was estimated at around
0.02% of the 1990 stock. Considering uncertainties in the data
used to calculate soil C stocks and changes, the small average
annual вЂ�lossвЂ™ could be regarded as вЂ�no changeвЂ™. В© 2005 Elsevier
Ltd. All rights reserved.
1763 Stock and distribution of total and corn-derived soil
organic carbon in aggregate and primary particle fractions
for different land use and soil management practices
Puget P., Lal R., Izaurralde C. et al. Soil Science 2005 170/4
(256-279)
Land use, soil management, and cropping systems affect stock,
distribution, and residence time of soil organic carbon (SOC).
Therefore, SOC stock and its depth distribution and association
with primary and secondary particles were assessed in long-term
experiments at the North Appalachian Experimental Watersheds
near Coshocton, Ohio, through 13 C techniques. These measurements were made for five land use and soil management
treatments: (1) secondary forest, (2) meadow converted from
no-till (NT) corn since 1988, (3) continuous NT corn since 1970,
(4) continuous NT corn-soybean in rotation with ryegrass since
1984, and (5) conventional plow till (PT) corn since 1984. Soil
samples to 70-cm depth were obtained in 2002 in all treatments.
Significant differences in soil properties were observed among
land use treatments for 0 to 5-cm depth. The SOC concentration
(g C kg-1 of soil) in the 0 to 5-cm layer was 44.0 in forest, 24.0 in
meadow, 26.1 in NT corn, 19.5 in NT corn-soybean, and 11.1 in
PT corn. The fraction of total C in corn residue converted to SOC
was 11.9% for NT corn, 10.6% for NT corn-soybean, and 8.3%
for PT corn. The proportion of SOC derived from corn residue
was 96% for NT corn in the 0 to 5-cm layer, and it decreased
gradually with depth and was 50% in PT corn. The mean SOC
sequestration rate on conversion from PT to NT was 280 kg C
ha-1 y-1 . The SOC concentration decreased with reduction in
aggregate size, and macro-aggregates contained 15 to 35% more
SOC concentration than microaggregates. In comparison with
forest, the magnitude of SOC depletion in the 0 to 30-cm layer
was 15.5 Mg C/ha (24.0%) in meadow, 12.7 Mg C/ha (19.8%) in
NT corn, 17.3 Mg C/ha (26.8%) in NT corn-soybean, and 23.3
Mg C/ha (35.1%) in PT corn. The SOC had a long turnover
time when located deeper in the subsoil. Additional research is
needed to understand association of SOC with particle and aggregate size fractions and temporal changes and depth-distribution
with regard to land use and soil management. Copyright В© 2005
by Lippincott Williams & Wilkins, Inc.
1764 Soil organic carbon sequestration rates in two longterm no-till experiments in Ohio
Jarecki M.K. and Lal R. Soil Science 2005 170/4 (280-291)
The effectiveness of no-till (NT) farming in reducing loss of soil
organic matter (SOM) depends on climate and soil properties.
Soil samples were obtained from two long-term experiments that
were designed to study the impact of tillage systems on crop
yields. However, the objectives of this experiment were to assess
the impact of NT on soil organic carbon (SOC) sequestration rate
and other soil properties and to estimate historic depletion of SOC
under different soil management practices with reference to the
undisturbed wooded control. The two long-term experiments in
Ohio studied were those sited at South Charleston and Hoytville.
The South Charleston (83В° 30 W and 39В° 48 N) experiment
was established in 1962 on Crosby silt loam (fine mixed, mesic
Aeric Ochraqualf). The site has long-term annual temperature
and precipitation of 10.8В°C and 1043 mm, respectively. Tillage
treatments for continuous corn (Zea mays) were NT, chisel plow
(CP), and moldboard plow (MP). The Hoytville (84В° 04 W and
41В° 03 N) experiment was established in 1987 on Hoytville
clay loam (fine, illitic mesic Mollic Epiaqualfs) soil. The site
has long-term annual temperature and precipitation of 9.9В°C and
845 mm, respectively. There were two crop rotations: (i) 2-year
corn-soybean (Glycine max) rotation with NT and subsoiling and
(ii) 3-year corn-soybean-oat (Avena sativa) rotation with NT, CP,
and rotational tillage soil management. The Hoytville clay site
is poorly drained, has higher clay content, and higher and more
even by distributed antecedent level of SOC in the soil profile
than does the South Charleston silt loam soil. No-til increased
SOC and N pools in the 0 to 5-cm layer in silt loam soil but
had no effect in clay soil. The rate of SOC sequestration in the
silt-loam soil under NT was 175 kg C ha-1 y -1 . The silt loam
soil had higher SOC and N stratification ratios in NT than in
MP and CP treatments, whereas the stratification ratios were low
and similar in all treatments in the clayey soil. For both soils,
there were no differences between tillage treatments in several
soil properties including texture, available water capacity, hydraulic conductivity (Ks ), and cation exchange capacity. The NT
decreased soil bulk density and pH in the 0 to 15-cm layer in
the silt loam soil. The plow til treatments had a small impact
on soil aggregation in clayey soil. The decline in water-stable
aggregates with reference to NT was no more than one sixth. In
the silt loam soil, however, the water-stable aggregates in plow
till treatments were merely one third of that in the NT treatment.
The historic loss of the SOC pool for 0 to 30-cm depth under
agricultural land use was 25 to 35% in silt loam and 19 to 25%
in the clayey soil. Copyright В© 2005 by Lippincott Williams &
Wilkins, Inc.
1765 Comparison of odorous volatile compounds from
fourteen different commercial composts using solid-phase
microextraction
Kim H., McConnell L.L. and Millner P. Transactions of the American Society of Agricultural Engineers 2005 48/1 (315-320)
In this study, odorous volatile compounds (OVCs) from marketready, commercial composts supplied by 14 different producers
were compared using a recently developed method involving
solid-phase microextraction (SPME) of headspace volatiles followed by GC analysis. The products analyzed were derived from
a cross-section of the wide array of compost feedstock ingredients
used in the U.S. (e.g., biosolids, yard trimmings, animal manure,
and industrial by-products). A variety of quality assessment tests
were performed using test procedures specified in a national certification program offered through the U.S. Composting Council.
Measurements of odorous chemicals (i.e., trimethylamine, carbon disulfide, dimethylsulfide, dimethyldisulfide, propionic acid,
and butyric acid) supplemented other quality aspects in the evaluation of stability. Result showed that relatively higher concentrations of reduced sulfur-containing compounds were detected
from marketable composts containing sewage sludge than from
composts produced with other feedstocks. The greatest amounts
of reduced sulfur-containing compounds were detected from a
compost containing a mixture of industrial sludge and agricultural byproducts. Pathogen indicator microbes for most composts
were within limits for Class A (U.S. EPA 40CFR Part503). Very
large numbers of fecal coliforms, E. coli, and Enterococcus were
present in the compost that produced the greatest concentrations
SOILS
of carbon disulfide and dimethylsulfide. Composts containing
sewage sludge and yard wastes produced relatively higher concentrations of propionic and butyric acids than those containing
other ingredients. The composition of OVCs in compost products can be objectively evaluated with the SPME method reported
here. Results in combination with other compost quality factors
may help compost producers improve product quality.
1766 Phosphorus speciation in manure and manureamended soils using XANES spectroscopy
Sato S., Solomon D., Hyland C. et al. Environmental Science
and Technology 2005 39/19 (7485-7491)
Previous studies suggested an increase in the proportion of calcium phosphates (CaP) of the total phosphorus (P) pool in soils
with a long-term poultry manure application history versus those
with no or limited application histories. To understand and predict long-term P accumulation and release dynamics in these
highly amended soils, it is important to understand what specific
P species are being formed. We assessed forms of CaP formed in
poultry manure and originally acidic soil in response to different
lengths of mostly poultry manure applications using P K-edge
X-ray absorption near-edge structure (XANES) spectroscopy.
Phosphorus K-edge XANES spectra of poultry manure showed
no evidences of crystalline P minerals but dominance of soluble
CaP species and free and weakly bound phosphates (aqueous
phosphate and phosphate adsorbed on soil minerals). Phosphate
in an unamended neighboring forest soil (pH 4.3) was mainly
associated with iron (Fe) compounds such as strengite and Feoxides. Soils with a short-term manure history contained both
Fe-associated phosphates and soluble CaP species such as dibasic calcium phosphate (DCP) and amorphous calcium phosphate
(ACP). Long-term manure application resulted in a dominance of
CaP forms confirming our earlier results obtained with sequential extractions, and a transformation from soluble to more stable
CaP species such as -tricalcium calcium phosphate (TCP). Even
after long-term manure application (>25 yr and total P in soil
up to 13 307 mg kg-1 ), however, none of the manure-amended
soils showed the presence of crystalline CaP. With a reduction
or elimination of poultry manure application to naturally acidic
soils, the pH of the soil is likely to decrease, thereby increasing
the solubility of Ca-bonded inorganic P minerals. Maintaining a
high pH is therefore an important strategy to minimize P leaching
in these soils. В© 2005 American Chemical Society.
1767 Copper(II) complexation by humic and fulvic acids
from pig slurry and amended and non-amended soils
Plaza C., Senesi N., Garca- Gil J.C. and Polo A. Chemosphere
2005 61/5 (711-716)
The effect of the consecutive annual additions of pig slurry at
rates of 0 (control), 90 and 150 m3 ha-1 y-1 over a 4-year period on the binding affinity for Cu(II) of soil humic acids (HAs)
and fulvic acids (FAs) was investigated in a field plot experiment under semiarid conditions. A ligand potentiometric titration method and a single site model were used for determining
the Cu(II) complexing capacities and the stability constants of
Cu(II) complexes of HAs and FAs isolated from pig slurry and
control and amended soils. The HAs complexing capacities and
stability constants were larger than those of the corresponding
FA fractions. With respect to the control soil HA, pig-slurry
HA was characterized by a much smaller binding capacity and
stability constant. Amendment with pig slurry decreased the
binding affinity of soil HAs. Similar to the corresponding HAs,
the binding affinity of pig-slurry FA was much smaller while that
of amended-soil FAs were slightly smaller when compared to the
control soil FA. The latter effect was, however, more evident with
increasing the amount of pig slurry applied to soil per year and
the number of years of pig slurry application. В© 2005 Elsevier
Ltd. All rights reserved.
1768 Leaf litter decomposition in a chaparral ecosystem,
Southern California
Quideau S.A., Graham R.C., Oh S.- W. et al. Soil Biology and
Biochemistry 2005 37/11 (1988-1998)
Decomposition losses from leaves of three evergreen chaparral species, scrub oak (Quercus dumosa), ceanothus (Ceanothus
crassifolius), and manzanita (Arctostaphylos glauca), were quantified over a 2-y field exposure using litterbags. Changes in
337
ash-free dry mass, C, and N were monitored at 2- to 6-month intervals at four replicate sites composed of patches of these three
chaparral species. Three proximate C fractions were extracted
from fresh and decomposing litter samples: polar and non-polar extractives (EXT), acid-solubles (ACID), and acid-insolubles
(KLIG). The chemical structure of fresh and decomposed litter
was additionally characterized using high-resolution solid-state
13 C NMR spectroscopy, while morphological properties were
examined by scanning electron microscopy (SEM). After 2 y, the
litters had lost between 20.7% 1.2 (Ceanothus) and 35.2% 6.8
(Quercus) of their original ash-free dry mass. The manzanita
decomposed at a significantly faster rate than the other two litter
types during the first few months of field exposure. Yet, after 2 y,
mass loss was greater for the oak. Differences in decomposition
rates could not be accounted for based on a single litter quality
index. Fresh manzanita exhibited a significantly higher N content, which could explain its initially faster decay rate. Fresh
oak litter, on the other hand, had a relatively high ACID and
O-alkyl C (O-ALK) content, which may have been responsible
for its decay pattern. Fresh ceanothus contained a relatively
low KLIG content, yet it decomposed more slowly than the two
other species. The solid-state 13 C NMR spectra of the ceanothus
litter had two peaks characteristic of proanthocyanidins, which
likely contributed to the recalcitrance of this litter type. SEM
revealed that ceanothus leaf surfaces were left nearly unchanged
after field exposure. In comparison, the oak and manzanita leaf
surfaces were pitted and covered by microbial growth to the point
of being unrecognizable. Taken together, our results indicate that
a combination of biological, physical and chemical factors need
to be examined to clarify the different decomposition rates and
patterns of these three chaparral species. В© 2005 Elsevier Ltd.
All rights reserved.
1769 Long-term application of organic manure and nitrogen
fertilizer on N 2 O emissions, soil quality and crop production
in a sandy loam soil
Meng L., Ding W. and Cai Z. Soil Biology and Biochemistry
2005 37/11 (2037-2045)
A long-term field experiment was established to determine the influence of mineral fertilizer (NPK) or organic manure (composed
of wheat straw, oil cake and cottonseed cake) on soil fertility.
A tract of calcareous fluvo-aquic soil (aquic inceptisol) in the
Fengqiu State Key Experimental Station for Ecological Agriculture (Fengqiu county, Henan province, China) was fertilized
beginning in September 1989 and N2 O emissions were examined
during the maize and wheat growth seasons of 2002-2003. The
study involved seven treatments: organic manure (OM), halforganic manure plus half-fertilizer N (1/2 OMN), fertilizer NPK
(NPK), fertilizer NP (NP), fertilizer NK (NK), fertilizer PK (PK)
and control (CK). Manured soils had higher organic C and N
contents, but lower pH and bulk densities than soils receiving
the various mineralized fertilizers especially those lacking P, indicating that long-term application of manures could efficiently
prevent the leaching of applied N from and increase N content
in the plowed layer. The application of manures and fertilizers
at a rate of 300 kg N ha-1 year-1 significantly increased N2 O
emissions from 150 g N2 O-N ha-1 year-1 in the CK treatment soil
to 856 g N2 O-N ha-1 year-1 in the OM treatment soil; however,
there was no significant difference between the effect of fertilizer
and manure on N2 O emission. More N2 O was released during
the 102-day maize growth season than during the 236-day wheat
growth season in the N-fertilized soils but not in N-unfertilized
soils. N2 O emission was significantly affected by soil moisture
during the maize growth season and by soil temperature during
the wheat growth season. In sum, this study showed that manure
added to a soil tested did not result in greater N2 O emission than
treatment with a N-containing fertilizer, but did confer greater
benefits for soil fertility and the environment. В© 2005 Elsevier
Ltd. All rights reserved.
1770 Dissolved organic carbon (DOC) as a parameter of
compost maturity
Zmora- Nahum S., Markovitch O., Tarchitzky J. and Chen Y. Soil
Biology and Biochemistry 2005 37/11 (2109-2116)
Despite numerous investigations of the maturation process of
composts, a simple and straightforward parameter which can
338
SOILS
predict plant response upon compost application has yet to be
defined. In light of results accumulated over a decade, we examined simple, chemical parameters of three composts from
three types of source materials (municipal solid waste (MSW),
separated cow manure (CSM), biosolids (BS)). These materials
were composted using different procedures and facilities. The
chemical parameters were correlated to the growth response of
cucumbers or ryegrass sown in potting media amended with
the composts sampled at different stages of the process. The
dissolved organic carbon (DOC) concentration of all composts
decreased rapidly within the first month, then, towards the end
of the process, stabilized at concentration below 4 g kg-1 . DOC
correlated highly and significantly to the absorbance at 465 nm
in all composts, and also to the C/N ratio. Nitrate evolution
was similar in all composts, but the final concentrations differed
among them. Plant biomass increased with composting time.
For CSM and BS compost maximum biomass was reached when
the DOC reached levels below 4 g kg-1 . DOC concentration
is suggested for use as a simple method of determining maturity, with 4 g kg-1 recommended as a threshold level indicating
maturity. Absorbance at 465 nm can be used instead of DOC
concentration after appropriate calibration. В© 2005 Elsevier Ltd.
All rights reserved.
1773 Humus accumulation and microbial activities in calcari-epigleyic fluvisols under grassland and forest diked in
for 30 years
Dilly O., Gnafl A. and Pfeiffer E.- M. Soil Biology and Biochemistry 2005 37/11 (2163-2166)
The accumulation and transformation of organic matter during
soil development is rarely investigated although such processes
are relevant when discussing about carbon sequestration in soil.
Here, we investigated soils under grassland and forest close to
the North Sea that began its genesis under terrestrial conditions
30 years ago after dikes were closed. Organic C contents of
up to 99 mg g-1 soil were found until 6 cm soil depth. The
humus consisted mainly of the fraction lighter than 1.6 g cm-3
which refers to poorly degraded organic carbon. High microbial
respiratory activity was determined with values between 1.57 and
1.17 g CO2 -C g -1 soil h-1 at 22В°C and 40 to 70% water-holding
capacity for the grassland and forest topsoils, respectively. The
microbial C to organic C ratio showed values up to 20 mg Cmic
g-1 C org . Although up to 2.69 kg C m-2 were estimated to be
sequestered during 30 years, the microbial indicators showed
intensive colonisation and high transformation rates under both
forest and grassland which were higher than those determined in
agricultural and forest topsoils in Northern Germany. В© 2005
Elsevier Ltd. All rights reserved.
1771 Improving quality of composted biowaste to enhance
disease suppressiveness of compost-amended, peat-based
potting mixes
Veeken A.H.M., Blok W.J., Curci F. et al. Soil Biology and
Biochemistry 2005 37/11 (2131-2140)
Biowaste can be converted into compost by composting or by
a combination of anaerobic digestion and composting. Currently, waste management systems are primarily focused on the
increase of the turnover rate of waste streams whereas optimisation of product quality receives less attention. This results in
low quality composts that can only be sold on bulk markets at
low prices. A new market for quality compost could be potting
mixes for horticultural container-grown crops to partially replace
non-renewable peat and increase the disease suppressiveness of
potting mixes. We report here on the effect of wetsieving biowaste prior to composting on compost quality and on disease
suppressiveness against the plant pathogen Pythium ultimum of
peat mixes amended with this compost. The increased organic
matter and decreased salt content of the compost allow for significantly higher substitution rates of peat by compost. In this study
up to 60% v/v compost peat replacement did not affect cucumber
growth. However, disease suppressiveness of the potting mixes
strongly increased from 31 to 94% when the compost amendment
rate was increased from 20 to 60%. It was shown that general
disease suppression for P. ultimum can only be effective when
the basal respiration rate is sufficiently high to support microbial
activity. In addition, organic matter of the compost should reach a
sufficient stability level to turn from disease conducive to disease
suppressive. Increasing the compost addition from 20 to 60%
did not significantly affect plant yield, yield variation were due
to differences in nutrient levels. It can be concluded that compost from wetsieved biowaste has high potential to replace peat
in growing media for the professional market. В© 2005 Elsevier
Ltd. All rights reserved.
1774 Organic N forms of a subtropical Acrisol under no-till
cropping systems as assessed by acid hydrolysis and solidstate NMR spectroscopy
Dieckow J., Mielniczuk J., Knicker H. et al. Biology and Fertility
of Soils 2005 42/2 (153-158)
This study was conducted to investigate the influence of landuse systems (grassland and cropland) and of long-term no-till
cropping systems [bare soil, oat/maize (O/M), pigeon pea+maize
(P+M)] on the composition of organic N forms in a subtropical
Acrisol. Soil samples collected from the 0- to 2.5-cm layer
in the study area (Eldorado do Sul RS, Brazil) were submitted
to acid hydrolysis and cross-polarization magic angle spinning
(CPMAS) 15 N and 13 C nuclear magnetic resonance (NMR) spectroscopies. The legume-based cropping system P+M contained
the highest contents of non-hydrolysable C and N, hydrolysable
C and N, amino acid N and hydrolysed unknown N. The relative
proportion of non-hydrolysable N was higher in bare soil (30.0%)
and decreased incrementally in other treatments based on the total
C and N contents. The amino acid N corresponded to an average
of 37.2% of total N, and was not affected by land use and notill cropping systems. The non-hydrolysable residue contained
lower O-alkyl and higher aromatic C concentrations, as revealed
by CPMAS 13 C NMR spectroscopy, and higher C:N ratio than
the bulk soil. No differences in the bulk soil organic matter
composition could be detected among treatments, according to
CPMAS 13 C and 15 N NMR spectra. In the non-hydrolysable
fraction, grassland showed a lower concentration of aromatic and
a higher concentration of alkyl C than other treatments. From
CPMAS 15 N NMR spectra, it could be concluded that amide
N from peptide structures are the main organic N constituent.
Amide structures are possibly protected through encapsulation
into hydrophobic sites of organic matter and through organomineral interaction.
1772 Soil nitrogen cycling under litter and coarse woody
debris in a mixed forest in New York State
Hafner S.D. and Groffman P.M. Soil Biology and Biochemistry
2005 37/11 (2159-2162)
Coarse woody debris (CWD) could alter N availability and transformations in the underlying soil and therefore contribute to spatial heterogeneity and influence ecosystem loss of N. We measured soil N concentrations and transformations in soil beneath
CWD and beneath a litter layer at a mixed forest in NY State.
We found that total and microbial biomass N was lower and that
microbial biomass C-to-N ratio was higher in soil beneath CWD.
Rates of N 2 O production and denitrification enzyme activity
were reduced beneath CWD. These results suggest that CWD is
an important controller of spatial heterogeneity in N dynamics
and may influence the magnitude of N loss in temperate forests.
В© 2005 Elsevier Ltd. All rights reserved.
1775 Effect of humic amendments on inorganic N, dehydrogenase and alkaline phosphatase activities of a Mediterranean soil
Lizarazo L.M., JordВґa J.D., JuВґarez M. and SВґanchez- Andreu J.
Biology and Fertility of Soils 2005 42/2 (172-177)
Dehydrogenase activity, alkaline phosphatase activity and NH4
+ , NO - and NO - concentrations were monitored in an aridisol
2
3
treated with three commercially available humic amendments.
The materials were of plant residue, lignite and peat origins.
The humus plant residues, fulvic acids, with a high content of
Kjeldahl-N, sustained high enzyme activities and highest levels
of NH 4 + , NO2 - and NO3 - . Humus lignite (mainly humic
acids) produced the highest dehydrogenase activity, whereas the
alkaline phosphatase activity was not as high as that amendment
with humus plant residues. The lower activity of alkaline phosphatase could not be attributed to the higher P content of humus
lignite. Nitrification was also low, probably due to the low N
content of this fertilizer. The amendment of humus peat origin
SOILS
(only humic acids) did not increase enzyme activity or inorganic
N concentrations of soil. Our results show that although these
materials are widely utilized and recommended as microbial and
plant activators, they all behave very differently, and the effects
on soil microbiological activity cannot be predicted solely on the
basis of their humic and/or fulvic acid contents.
1776 Degradation and preservation of vascular plant-derived biomarkers in grassland and forest soils from Western
Canada
Otto A. and Simpson M.J. Biogeochemistry 2005 74/3 (377-409)
The total solvent extracts (TSE) of mineral and organic horizons
of selected soils and overlying vegetation were analyzed using
gas chromatography-mass spectrometry (GC-MS) to determine
the composition of solvent-extractable (вЂ�freeвЂ™) lipids in soils and
to study the degradation and possible preservation of vascular
plant-derived molecular markers (biomarkers) in soils. Major
compound classes in the TSE of soils and vegetation included a
homologous series of aliphatic lipids (alkanoic acids, alkanols,
alkanes), steroids, and terpenoids. Characteristic patterns of aliphatic and cyclic biomarkers derived from the overlying, native
vegetation were recognized in the associated soil samples indicating the preservation of lipids from the external waxes of vascular
plants in the soil organic matter (SOM). The observed biomarker
patterns in the grassland soils (Brown Chernozems) were similar
to the compounds identified in their major source vegetation,
Western Wheatgrass. A similar composition of biomarkers was
observed in Aspen leaves and the soil horizons of the forestgrassland transition soil (Dark Gray Chernozem). The Lodgepole
Pine needles yielded a characteristic pattern of diterpenoids that
was also detected in leaf litter and the O horizon of the associated forest soil (Brunisol). The results demonstrate that solvent
extractable biomarkers derived from vascular plants maintain
their characteristic pattern of aliphatic and cyclic lipids despite
ongoing degradation processes and are thus valuable molecular
markers for the determination of the sources of SOM. Furthermore, the abundance of aliphatic wax lipids in plant material and
soils decreased at higher rates than the steroids and terpenoids
indicating the preferential degradation of aliphatic over cyclic
biomarkers. Most of the plant-derived steroids and terpenoids
identified in the soils were unaltered, preserved biomolecules as
observed in the source vegetation, but minor amounts of their
degradation products were also present. Oxidation products of
plant sterols are reported here for the first time in soils. The
detected alteration products of steroids and diterpenoids are consistent with the oxidative degradation of free cyclic biomarkers
in decomposing plant material and soils. В© Springer 2005.
1777 Fate of the metal-binding soluble organic matter
throughout a soil profile
Dudal Y., SВґevenier G., Dupont L. and Guillon E. Soil Science
2005 170/9 (707-715)
Crop residues are a major source of soluble organic matter (SOM)
in agricultural soils. The fate of this complex mixture of organic
compounds is mainly controlled by the biodegradation by soil microbes, sorption to the different soil surfaces, and transfer through
the soil profile along with the water flow. During this transfer, the
soluble organic matter can bind micropollutants such as metals
and co-transport them down the soil profile to the groundwater.
However, monitoring usually consists in measuring the organic
content of the aqueous sample (dissolved or water-soluble organic matter), rarely its reactivity. The objective of this study
was to monitor both the SOM content and its reactivity toward
metal cations during its transport through the soil. Therefore,
samples were collected from a field experiment performed on a
2-m-deep vadose zone over a 7-month period. The metal-binding
capacity of 84 of these samples was quantified for Cu2+ , Fe2+ ,
and Mn 2+ , using the quenching of SOM fluorescence that is
observed when increasing concentrations of metal cations are
added to the SOM sample. A simple Langmuir-type model was
used to quantify the three binding constants for each SOM sample and the amount of metal that it can bind. This method gives
binding constants for SOM with each metal cation that respect
the general observations made for natural organic matter (log K
= 5.31, 4.79, and 4.77 for Cu 2+ , Fe2+ and Mn2+ , respectively,
for a surface soil sample). Although the SOM content decreased
from 10 to 2 mg L-1 over the 2-m-deep vadose zone, the profile
339
of the overall complexation constant was homogeneous (log K
= 5.36
0.05 for Cu2+ ), indicating that only a small portion
of the SOM was responsible for metal binding. The influence
of environmental parameters such as residue incorporation, soil
temperature, and rainfall events on the amount of metals that
SOM can bind was assessed. Strong rainfall events were able to
transport a limited amount of metal-binding SOM (up to 1 M
Cu2+ per sample), even in the case where very low organic matter
content was found. The freeze-thaw cycle liberated much more
metal-binding SOM (4.8 M Cu2+ per sample) in the aqueous
phase at the soil surface. This functional monitoring appears useful to quantify the potential environmental effects of the diverse,
complex, and evolving SOM. Copyright В© 2005 by Lippincott
Williams & Wilkins, Inc.
1778 Changes in clay-associated organic matter quality in
a C depletion sequence as measured by differential thermal
analyses
Plante A.F., Pernes M. and Chenu C. Geoderma 2005 129/3-4
(186-199)
Land use changes result in significant decreases in soil organic
matter stocks due to enhanced mineralization attributed to increased tillage, and due to decreased organic matter inputs. The
current paradigm of soil organic matter dynamics suggests that
decreasing organic matter stocks are also associated with shifts
in organic matter quality to more resistant fractions as the more
labile pools are decomposed. The objectives of the current study
were to characterize changes in clay-associated organic matter
quality in a soil C depletion sequence in terms of thermal properties, and to thermally characterize peroxide-resistant organic
matter. Clay-sized fractions were isolated from a sequence of
soils ranging from native forest to long-term bare fallow, and
analyzed using thermogravimetry (TG) and differential scanning
calorimetry (DSC) before and after hydrogen peroxide treatment.
Differential scanning calorimetry traces had exothermic maxima
near 285 and 333В°C, consistent with analyses of chemically extracted organic matter and humic substances reported in the literature. Peak fitting analyses showed that these maxima consisted
of several hidden peaks, but their interpretation is problematic.
The qualitative shifts in the thermal properties of clay-associated
organic matter with differing land use observed in the DSC traces
were quantified using cultivation and fallow treatment to forest
ratios. Thermogravimetric mass loss ratios were greater in the
thermally labile (180-310В°C) exothermic region than in the more
thermally resistant (310-450В°C) exothermic region. Similarly,
ratios of peak heights and areas for the fitted DSC peaks were
higher for the 324В°C peak, compared to peaks at 257 and 284В°C.
The higher ratios indicate that the more thermally resistant organic matter has been retained and the more thermally labile
organic matter is lost. The observed shift in the distribution of organic matter from thermally labile to thermally resistant fractions
from forest to long-term bare fallow clay samples is consistent
with the current paradigm of decomposition consisting of a shift
to more biologically resistant fractions with increasing time under
cultivation and decreasing organic matter inputs. These results
suggest that the thermal properties of clay-associated organic
matter are related to their biological decomposability. Hydrogen peroxide treatment of clay samples removed approximately
87% of the initial organic C in all samples, and peroxide-resistant organic matter was found to be more thermally stable than
the whole. However, thermal analyses of the peroxide-resistant
fraction did not show any changes in thermal properties with
decreases in total C content. Rather than isolating a biologically
resistant pool of organic matter, peroxide-resistant organic matter may isolate an inert pool of soil organic matter with thermal
properties consistent with the presence of black carbon, which
remains unchanged by changes in land use. В© 2005 Elsevier B.V.
All rights reserved.
1779 Ecosystem model spin-up: Estimating steady state
conditions in a coupled terrestrial carbon and nitrogen cycle
model
Thornton P.E. and Rosenbloom N.A. Ecological Modelling 2005
189/1-2 (25-48)
We tested a variety of methods for determining steady state solutions for Biome-BGC, a coupled model of terrestrial water,
carbon, and nitrogen dynamics. Our objective was to identify
340
SOILS
methods that could reduce the computational cost of model spinup relative to simulations running under the modelвЂ™s native dynamics, while retaining or improving upon the simulation quality,
where quality is judged by comparison to assumed values for the
true steady state solution. Two classes of methods were tested: ad
hoc methods that approximate steady state by taking advantage
of specific characteristics of the modeled dynamics to produce
individual time trajectories through the model state space, and
general multivariate minimization methods that iteratively explore multiple time trajectories through state space in search of
a reasonable steady state solution. We examined the behavior
of these methods for both woody and herbaceous vegetation
simulations. We found that both the ad hoc and the generalized
methods, parameterized appropriately, could provide reductions
in computational cost of 50-75% compared to the modelвЂ™s native
dynamics. With the exception of the generalized methods for
the woody vegetation case, we also found that the quality of the
simulated steady state solution was as good as or better than the
native dynamics approach. The one method which performed
consistently well across sites and vegetation types involved an
acceleration of decomposition rates for the spin-up phase, resulting in 73 and 66% reductions in computational cost for woody
and herbaceous vegetation types, respectively. В© 2005 Elsevier
B.V. All rights reserved.
1780 Carbon and decomposition model Yasso for forest soils
Liski J., Palosuo T., Peltoniemi M. and SievВЁanen R. Ecological
Modelling 2005 189/1-2 (168-182)
Models are needed to estimate dynamics of carbon in forest soils,
because changes in soil carbon are laborious to measure, and future levels of soil carbon can only be predicted using models.
Current process-oriented soil carbon models are not suitable to
all forestry-related applications. This is because they require
specific input information that is not available for all forests, and
their time step is shorter than a year which is typically used in
forestry. We developed a dynamic soil carbon model Yasso to be
used in forestry applications. Yasso simulates the stock of soil
carbon, changes in this stock and the release of carbon from soil
on an annual basis. It needs estimates of litter production, information on litter quality and basic data on climate to run. Yasso
consists of five decomposition compartments and two woody
litter compartments. Its parameter values were determined based
on measurements of litter decomposition and soil carbon. The
reliability of the output of Yasso was assessed by conducting an
uncertainty analysis and comparing model-calculated estimates
of soil carbon to measurements taken at different forest sites
in southern Finland. According to the uncertainty analysis, the
estimates for the amount of soil carbon are uncertain by nature,
because they depend mostly on uncertain humus parameters.
Still, when linked to a forest simulator to calculate litter production, Yasso gave similar estimates for the amount of soil carbon
as were measured. The estimates for changes in soil carbon, on
the other hand, are more reliable by nature because they depend
on more accurately known parameters. These and other tests
conducted so far suggest that Yasso is applicable to forests in a
wide range of environments. Further tests will increase confidence in using it for different soils. В© 2005 Elsevier B.V. All
rights reserved.
1781 Litter decomposition affected by climate and litter
quality - Testing the Yasso model with litterbag data from
the Canadian intersite decomposition experiment
Palosuo T., Liski J., Trofymow J.A. and Titus B.D. Ecological
Modelling 2005 189/1-2 (183-198)
Litterbag experiments provide valuable data for testing the accuracy of predictions of decomposition from soil carbon models.
The soil carbon model Yasso describes litter decomposition based
on basic climate and litter quality information, and was calibrated
using European litterbag data. In this study, we tested the predictive capabilities of Yasso using independent litterbag data for
10 foliage litter types decomposed for 6 years at 18 upland forest
sites across Canada (CIDET). The model underestimated mass of
leaf litters remaining on CIDET sites, with only a small systematic error in predicting the effects of climate when effective temperature sum was used as the temperature variable in the model.
The overall rate of decomposition was predicted correctly when
mean annual temperature was used as the temperature variable,
but then the model substantially overestimated climatic effects.
The model correctly predicted differences in decomposition rates
among litter types in the early years of decomposition, but underestimated them in later years. The decomposition rate of the
litter type richest in phenolic compounds (larch needles) was
systematically overestimated, and that of the litter type richest in
O-alkyl compounds (grass leaves) was systematically underestimated. Accounting for these factors would improve the general
applicability of the model. However, accounting for the initial nitrogen concentration of litter did not improve the accuracy of the
model unless the initial lignin (i.e., acid unhydrolyzable residue)
content was also taken into account. We conclude that the model
Yasso accounts for most of the effects of climate and initial litter
quality on the decomposition of a range of foliage litter types
under varying climate conditions. Recalibration of the reference
decomposition rates used in the model may improve the accuracy
when applying the model outside of Europe. В© 2005 Elsevier
B.V. All rights reserved.
1782 Mathematical modelling of the composting process: A
review
Mason I.G. Waste Management 2006 26/1 (3-21)
In this paper mathematical models of the composting process
are examined and their performance evaluated. Mathematical
models of the composting process have been derived from both
energy and mass balance considerations, with solutions typically
derived in time, and in some cases, spatially. Both lumped and
distributed parameter models have been reported, with lumped
parameter models presently predominating in the literature. Biological energy production functions within the models included
first-order, Monod-type or empirical expressions, and these have
predicted volatile solids degradation, oxygen consumption or
carbon dioxide production, with heat generation derived using
heat quotient factors. Rate coefficient correction functions for
temperature, moisture, oxygen and/or free air space have been
incorporated in a number of the first-order and Monod-type expressions. The most successful models in predicting temperature
profiles were those which incorporated either empirical kinetic
expressions for volatile solids degradation or CO2 production, or
which utilised a first-order model for volatile solids degradation,
with empirical corrections for temperature and moisture variations. Models incorporating Monod-type kinetic expressions
were less successful. No models were able to predict maximum,
average and peak temperatures to within criteria of 5, 2 and 2В°C,
respectively, or to predict the times to reach peak temperatures to
within 8 h. Limitations included the modelling of forced aeration
systems only and the generation of temperature validation data
for relatively short time periods in relation to those used in fullscale composting practice. Moisture and solids profiles were
well predicted by two models, but oxygen and carbon dioxide
profiles were generally poorly modelled. Further research to
obtain more extensive substrate degradation data, develop improved first-order biological heat production models, investigate
mechanistically-based moisture correction factors, explore the
role of moisture tension, investigate model performance over
thermophilic composting time periods, provide more information
on model sensitivity and incorporate natural ventilation aeration
expressions into composting process models, is suggested. В©
2005 Elsevier Ltd. All rights reserved.
1783 The determination of biological stability of composts
using the Dynamic Respiration Index: The results of experience after two years
Adani F., Ubbiali C. and Generini P. Waste Management 2006
26/1 (41-48)
Biological stability was ascertained by using the Dynamic Respiration Index (DRI) on 144 samples of compost during the years
2003 and 2004, as a routine service for private subjects. Data
obtained were collected and are critically discussed in this paper
by using other parameters registered during tests, i.e., biomass
temperature (T), specific airflow rate (Qs ) and biomass analytical
data (pH). Good linear correlations were obtained for DRI vs. T,
DRI vs. Qs and DRI vs. pH, confirming expected results based
on the theoretical discussion. Consequently, using the analytical method proposed in this paper means both T and Q can be
used as additional parameters for measurement of the biological
SOILS
stability of compost. As a result, T values of 25.8 and 30.5В°C,
and specific airflow rate of 8.6 and 13.4 m3 Mg-1 VS h-1 were
found corresponding to 500 and 1000 mg O2 kgVS-1 h-1 , which,
respectively, indicate a high and a medium degree of biological
stability. В© 2005 Elsevier Ltd. All rights reserved.
1784 Carbon dioxide and ammonia emissions during composting of mixed paper, yard waste and food waste
Komilis D.P. and Ham R.K. Waste Management 2006 26/1 (6270)
The objective of the work was to provide a method to predict
CO2 and NH3 yields during composting of the biodegradable
fraction of municipal solid wastes (MSW). The compostable portion of MSW was simulated using three principal biodegradable
components, namely mixed paper wastes, yard wastes and food
wastes. Twelve laboratory runs were carried out at thermophilic
temperatures based on the principles of mixture experimental
and full factorial designs. Seeded mixed paper (MXP), seeded
yard waste (YW) and seeded food waste (FW), each composted
individually, produced 150, 220 and 370 g CO2 -C, and 2.0, 4.4
and 34 g NH3 -N per dry kg of initial substrate, respectively.
Several experimental runs were also carried out with different
mixtures of these three substrates. The effect of seeding was
insignificant during composting of food wastes and yard wastes,
while seeding was necessary for composting of mixed paper.
Polynomial equations were developed to predict CO2 and NH3
(in amounts of mass per dry kg of MSW) from mixtures of MSW.
No interactions among components were found to be significant
when predicting CO2 yields, while the interaction of food wastes
and mixed paper was found to be significant when predicting
NH3 yields. В© 2005 Elsevier Ltd. All rights reserved.
1785 Soil mineral-organic matter-microbe interactions: Impacts on biogeochemical processes and biodiversity in soils
Huang P.- M., Wang M.- K. and Chiu C.- Y. Pedobiologia 2005
49/6 (609-635)
Soils are the central organizer of the terrestrial ecosystem. Their
colloidal and particulate constituents, be they minerals, organic
matter, and microorganisms, are not separate entities; rather, they
are constantly interacting with each other. Interactions of these
components control biogeochemical reactions, namely, the formation of short-range-ordered metal oxides, catalysis of humic
substance formation, enzymatic stability and activity, mineral
transformation, aggregate turnover, biogeochemical cycling of
C, N, P, and S, and the fate and transformation of organic and inorganic pollutants. Furthermore, the impacts of mineral-organic
matter-microorganism interactions and associated biogeochemical reactions and processes on biodiversity, species composition,
and sustainability of the terrestrial ecosystem deserve close attention for years to come. This paper integrates the frontiers of
knowledge on this subject matter, which is essential to uncovering
the dynamics and mechanisms of terrestrial ecosystem processes
and to developing innovative management strategies to sustain
ecosystem health on the global scale. В© 2005 Elsevier GmbH.
All rights reserved.
1786 Effects of soil temperature and humidity on soil respiration rate under Pinus sylvestriformis forest (Chinese)
Liu Y., Han S., Hu Y. and Dai G. Chinese Journal of Applied
Ecology 2005 16/9 (1581-1585)
Employing root-wrenching method and LI-6400-09 soil respiration chamber, this paper measured the diurnal changes of soil
respiration rate with and without roots in situ on June 17, August 5, and October 10, 2003. The seasonal changes of soil
respiration were also measured from May to September, 2004.
The results showed that both the total and the root-wrenched
soil respiration appeared single diurnal pattern, with the peaks
presented during 12:00-14:00. The diurnal fluctuation of soil
respiration on August 5 was smaller than that on June 17 and
October 10. There were also obvious seasonal changes in total
and root-wrenched soil respiration, as well as in root respiration,
which were higher from June to August but lower in May and
September. The average total soil respiration, root-wrenched
soil respiration, and root respiration were 3.12, 1.94 and 1.18
mol CO2 m-2 s-1 , respectively, and the contribution of roots to
total soil respiration ranged from 26.5% to 52.6% from May to
September, 2004. There were exponential correlations between
341
respiration rate and soil temperature, and linear correlations between respiration rate and soil humidity. The Q10 values were
2.44, 2.55 and 2.27 for total soil respiration, root-wrenched soil
respiration, and root respiration, respectively. The effect of soil
temperature on root-wrenched soil respiration was lager than that
on total soil respiration and root respiration. Soil humidity had a
larger effect on total soil respiration than on root respiration and
root-wrenched soil respiration.
1787 Temporal variation of soil respiration on sloping pasture of Heihe River basin and effects of temperature and soil
moisture on it (Chinese)
Chang Z., Shi Z., Feng Q. and Su Y. Chinese Journal of Applied
Ecology 2005 16/9 (1603-1606)
Employing LiCor 6400 gas exchange analyzer and soil respiration chamber attachment (LiCor Inc., Lincoln, NE, USA), this
paper continuously measured the soil surface CO2 effluxes on
the sloping pasture of Heihe River basin from early April to late
October 2003 to investigate the soil CO2 efflux rate and its feedback to the changes of climate and land use. The results showed
that from May to October, the diurnal variation of soil respiration
was low at night, the lowest at 7:00, 6:30, 5:30, 6:00 and 7:00,
raised rapidly at 7:00-8:30, and then descended at 16:00-18:30.
The maximum soil CO2 efflux appeared at 15:00, 14:30, 14:30,
13:30, 14:00 and 15:00. The mean daily soil respiration rate was
0.31-6.98 mol m-2 s-1 , with the maximum in July and August,
the second in May and September, and nearly consistent in April
and October. Soil respiration rate had an exponential and power
correlation with temperature and soil moisture, respectively.
1788 Affecting factors of soil microorganism and root respiration (Chinese)
Jia B., Zhou G., Wang F. and Wang Y. Chinese Journal of Applied
Ecology 2005 16/8 (1547-1552)
Soil respiration is an important part of the carbon cycle in terrestrial ecosystems, and its contribution to the global carbon budget
has been the focus of wide concern. Researches on the affecting
factors of soil microorganism and root respiration, the main components of soil respiration, contribute to the understanding of the
role of soil respiration on global carbon cycle, and to the accurate
evaluation of global carbon budget. This paper reviewed the direct and indirect affecting factors of soil microorganism and root
respiration, including climate factors, soil properties, vegetation
and litterfall, air CO2 concentration, and human activities. These
affecting factors were interactive, and their contributions to soil
microorganism and root respiration varied in temporal and spatial
scales. The study on natural and anthropogenic factors of soil
microorganism and root respiration was emphasized, and some
related research tasks in the future were also proposed.
Biota
1789 Effects of three soil tillage systems on some biological
activities in an Ultisol from southern Chile
Alvear M., Rosas A., Rouanet J.L. and Borie F. Soil and Tillage
Research 2005 82/2 (195-202)
Intensive tillage for annual crop production may be affecting soil
health and quality. However, tillage intensity effects on biological activities of volcanic-derived soils have not been systematically investigated. We evaluated the effects of three different
tillage practices on some biological activities of an Ultisol from
southern Chile during the third year of a wheat-lupin-wheat crop
sequence. Treatments were: no tillage with stubble burning
(NTB), no tillage without stubble burning (NT) and conventional
tillage with disk-harrowing and stubble burning (CT). Biological
activities were evaluated in winter and summer at 0-200 mm and
at three soil depths (0-50, 50-100 and 100-200 mm) in winter.
Total organic C and N were significantly higher under no-tillage
systems than CT. In general, NT increased C and N of microbial
biomass in comparison with CT, especially in winter. Microbial
biomass C was closely associated with microbial biomass N (r
= 0.986, P < 0.05); acid phosphomonoesterase (r = 0.999, P <
0.05); -glucosidase (r = 0.978, P < 0.05), and others. Changes
in biological activities occurred mainly in the upper soil layer
342
SOILS
(0-50 mm depth) in spite of the short duration of the experiment.
Biological activities could be used as practical biological indicators to apply the more appropriate management systems for
increasing soil sustainability or productivity. В© 2004 Elsevier
B.V. All rights reserved.
1790 Bacterial, azotobacter, actinomycetes, and fungal population in soil after diazinon, imidacloprid, and lindane treatments in groundnut (Arachis hypogaea L.) fields
Singh J. and Singh D.K. Journal of Environmental Science and
Health - Part B Pesticides, Food Contaminants, and Agricultural
Wastes 2005 40/5 (785-800)
Bacterial, azotobacter, actinomycetes, and fungal populations
were determined in groundnut (Arachis hypogaea L.) fields between July and November for three consecutive years (19971999) after insecticide treatments. Diazinon was applied for both
seed and soil treatments. However, imidacloprid and lindane
were used for seed treatments. An average half-life (t1/2 ) of
diazinon in seed- and soil-treated fields was found to be 29.32
and 34.87 days, respectively. Its residues were found for 60
days in both cases. In diazinon seed treatment, an increase in
azotobacter, fungi, and actinomycetes populations was observed
in samples from the 15th and 30th days, and this trend continued
until crop harvest. However, the bacterial population had not
been affected by this treatment. The diazinon soil treatment
had indicated some significant adverse effects on fungi and actinomycetes population, which recovered after 30 days. The
population of bacteria and azotobacter increased significantly in
this treatment. The residues of imidacloprid and lindane were
found for 90 and 120 days with an average half-life of 40.9 and
53.3 days, respectively. Imidacloprid had no significant effect on
fungi and actinomycetes populations up to 15 days, and between
15 to 60 days some adverse effects were indicated. However,
some significant increases in bacterial and azotobacter population were observed. Lindane had no effect on bacterial and
fungal population. However, its adverse effects were observed
in actinomycetes and azotobacter populations between 30 to 60
days. Copyright В© Taylor & Francis Inc.
1791 Does the positive feedback effect of nematodes on the
biomass and activity of their bacteria prey vary with nematode species and population size?
Fu S., Ferris H., Brown D. and Plant R. Soil Biology and Biochemistry 2005 37/11 (1979-1987)
Two nematode species (Cruznema tripartitum and Acrobeloides
bodenheimeri) were selected to test the hypotheses that bacterialfeeding nematodes affect bacterial biomass and activity and that
this feedback effect varies with nematode species and population
size. For each species, nematodes of three initial population sizes
were inoculated onto bacterial colonies in separate microcosms.
Nematode population, bacterial biomass and CO2 production
were monitored in parallel microcosm settings. The responses
of bacterial biomass to nematode species were different. Bacterial biomass increased significantly on d 8 in the presence of
Acrobeloides when its initial numbers were 20 and 100 per microcosm; and bacterial biomass increased significantly on d 4 in
the presence of Cruznema when its initial numbers were 5 and
20 per microcosm. Daily CO2 production of the microcosms
with initial population sizes of 5, 20 and 100 Cruznema or of
5 and 100 Acrobeloides was significantly greater than that in
microcosms without nematodes. However, the CO2 production
of the microcosms with initial population of 20 Acrobeloides was
not significantly different from that of the microcosms without
nematodes. The increase in daily CO2 production per microcosm
by Cruznema was generally greater than that by Acrobeloides for
the first few days of the experiment. Nevertheless, the increase in
daily CO2 production by an individual nematode was similar for
both species and was a decreasing function of the initial nematode
numbers. The feedback effect of each nematode species on its
bacterial prey was estimated by fitting both bacterial biomass and
CO2 production data to a model. Model outputs demonstrated
that the feedback effect of Cruznema on bacteria was greater than
that of Acrobeloides during the course of the experiment and the
feedback effect of each species was not linearly correlated to
initial nematode population sizes. Cruznema increased bacterial
biomass and activity by a factor of 3.75-4.55 over the first 4 d,
while Acrobeloides increased it by a factor between 1.97 and
3.40.
1792 Physiological and molecular characterisation of microbial communities associated with different water-stable
aggregate size classes
VВЁaisВЁanen R.K., Roberts M.S., Garland J.L. et al. Soil Biology
and Biochemistry 2005 37/11 (2007-2016)
We determined if the structure and function of microbial communities associated with different aggregate size classes was
influenced when the aggregate formation occurred under either nitrogen (N) limitation (straw only incubation treatment)
or carbon (C) limitation (straw+N incubation treatment). Using
a combination of community-level physiological (BD Oxygen
Biosensor assay) and molecular (terminal restriction fragment
length polymorphism; T-RFLP) profiling methods, we found
differences in both microbial community composition and the
physiological response of these communities between different
aggregate size classes. The response of fungal and bacterial
communities to вЂ�straw onlyвЂ™ and вЂ�straw+NвЂ™ treatments differed in
that bacterial community composition was affected by the treatments, whereas fungal community composition was not. The
magnitude of change in the bacterial community response increased with decreasing aggregate size. However, there were no
significant differences in the mean bacterial community richness
(number of different terminal restriction fragments; TRFs) between different aggregate size classes for the two treatments. In
general, microbial communities associated with larger aggregate
size fractions (large and small macroaggregates) were found to
have a significantly faster respiratory response than the communities associated with microaggregates. Application of the
fungal inhibitor cycloheximide resulted in a significant reduction
in the utilization of cellulose, chitin, mannose, xylan, and xylose
by the microbial communities associated with all aggregate size
classes, indicating that fungi are significant contributors to the
utilization of these compounds. Our results demonstrate that the
BD Oxygen Biosensor assay offers a valuable new tool for community level physiological profiling. When used in combination
with census-based methods such as T-RFLP, a greater level of
resolution can be achieved. В© 2005 Elsevier Ltd. All rights
reserved.
1793 Relationship between plants and soil microbial communities in fertilized grasslands
Benizri E. and Amiaud B. Soil Biology and Biochemistry 2005
37/11 (2055-2064)
The relationship between biodiversity and ecosystem functioning is of major scientific concern today. Few studies though
have measured the interactions between soil microorganisms and
plant diversity, the purpose of this study was to examine the link
between plant diversity and microbial communities in fertilized
versus unfertilized grasslands. Experiments were carried out on a
permanent grassland in north-eastern France where agricultural
practices had remained unchanged for the last 13 years. The
experimental design included two plots of 300 m2 (fertilized at
120 kg N ha-1 or non-fertilized). Plots were replicated into three
equal sub-plots (100 m 2 ). From each sub-plot, six samples
of soil and vegetation were taken at three dates during floristic development. At sampling, ground cover of each species
was estimated, and total amount of C and N was determined in
aboveground and root biomass. Soil samples were analyzed in
order to measure the metabolic fingerprints of microorganisms
using BiologВ® GN2 microplates. Floristic composition and carbon substrate utilization patterns of rhizobacterial communities
were more diversified in unfertilized than fertilized plots. In
unfertilized plots, the development of Convolvulus arvensis and
two legumes (Trifolium pratense and Trifolium repens) may help
maintain observed floristic diversity. Moreover, an inversion of C
and N distribution between aboveground and root biomass during
the vegetation cycle probably induced a variation of rhizodeposition. This phenomenon could explain the differences of rhizobacterial metabolic fingerprints observed between experimental
plots. В© 2005 Elsevier Ltd. All rights reserved.
SOILS
1794 Soil feedback effects to the foredune grass Ammophila
arenaria by endoparasitic root-feeding nematodes and whole
soil communities
Brinkman E.P., Troelstra S.R. and Van Der Putten W.H. Soil
Biology and Biochemistry 2005 37/11 (2077-2087)
In coastal foredunes, the grass Ammophila arenaria develops
a soil community that contributes to die-back and replacement
by later successional plant species. Root-feeding nematodes
and pathogenic soil microorganisms are involved in this negative
feedback. Regular burial by wind-blown beach sand results in
vigorous growth of A. arenaria, probably because of enabling a
temporary escape from negative soil feedback. Here, we examine
the role of root-feeding nematodes as compared to the whole soil
community in causing negative feedback to A. arenaria. We performed a 3-year sand burial experiment in the field and every year
we determined the feedback of different soil communities to plant
growth in growth chamber bioassays. In the field, we established
A. arenaria in tubes with beach sand, added three endoparasitic
root-feeding nematode species (Meloidogyne maritima, Heterodera arenaria and Pratylenchus penetrans) or root zone soil to the
plants, and created series of ceased and continued sand burial.
During three subsequent years, plant biomass was measured and
numbers of nematodes were counted. Every year, bioassays
were performed with the field soils and biomass of seed-grown
A. arenaria plants was measured to determine the strength of
feedback of the established soil communities to the plant. In the
field, addition of root zone soil had a negative effect on biomass
of buried plants. In the bioassays, addition of root zone soil also
reduced the biomass of newly planted seedlings, however, only
in the case when the field plants had not been buried with beach
sand. Addition of the three endoparasitic root-feeding nematodes
did not influence plant biomass in the field and in the bioassays.
Our results strongly suggest that the negative feedback to A.
arenaria is not due to the combination of the three endoparasitic
nematodes, but to other components in the soil community, or
their interactions with the nematodes. В© 2005 Elsevier Ltd. All
rights reserved.
1795 Microbial carbon dynamics in nitrogen amended Arctic tundra soil: Measurement and model testing
Stapleton L.M., Crout N.M.J., SВЁawstrВЁom C. et al. Soil Biology
and Biochemistry 2005 37/11 (2088-2098)
We examined the responses of grazers (protozoa and nematodes)
and their main food sources to low levels of nitrogen (N) fertilisation and applied carbon (C) flux models to our data. Replicate
plots of tundra soil adjacent to the Kongsfjorden (Svalbard 78В°N)
were amended with ammonium and nitrate at concentrations of
1 and 5 kg N ha-1 to assess the impact of anthropogenic N deposition over three summers. Bacterial abundance as determined
using the fluorochrome SYBR Green and epifluorescence microscopy ranged between 9.73 108 and 102.49 108 cells/g dry
wt of soil, with a significant response to N addition occurring
only during the second sampling in 2001. Despite little change
in bacterial biomass, bacterial production (measured by the incorporation of 3 H thymidine into DNA) during the second sampling
in 2002, increased in NH4 enriched plots compared to control and
NO3 amended plots, indicating that NH 4 was the preferred source
of inorganic N. The main bacterial predators were heterotrophic
flagellates (HNAN) and naked amoebae, which showed no significant response to the N addition. HNAN showed a correlation
with bacterial abundance suggesting a dependence on bacteria
as a food source. The inability of a microbial C flux model to
fit our data (RWSS/data=18.6, r 2 =0.088) was at least partly due
to insufficient bacterial production to meet the C demands of
predator taxa, and high variability in the data over time. This is
reflected in the performance statistics for model variants where
select microbial taxa and data were removed. The optimal model
in terms of predictive utility was a model with data from 2002
only, minus naked amoebae (RWSS/data=2.45, r2 =0.806). В©
2005 Elsevier Ltd. All rights reserved.
1796 Responses of oribatid mite communities to summer
drought: The influence of litter type and quality
Taylor A.R. and Wolters V. Soil Biology and Biochemistry 2005
37/11 (2117-2130)
A litterbag experiment was used to study the impact of extended
periods of summer drought on the structure of oribatid mite com-
343
munities (Acari, Oribatida) developing in two litter types (beech,
spruce) of two qualities (fresh, pre-incubated). Within each litter
type, litter quality determined species composition and densities
and, in turn, this determined the impact of drought upon the
oribatid mite communities. In both litter types, drought had a
greater impact on community development in the pre-incubated
compared to the fresh litter. In the short-term perspective of the
present study, oribatid mite communities in beech litter were less
sensitive to summer drought than those in spruce litter. This
was partly due to the presence of site-specific, drought-tolerant
species but seemed also strongly related to differences in the decomposition patterns between the litter types. Marked changes
in densities and composition of oribatid communities after only
one period of summer-drought suggest that there is a potential for
a significant alteration of oribatid community structure in both
litter types if climatic changes persist. В© 2005 Elsevier Ltd. All
rights reserved.
1797 Earthworm ecological groupings based on 14 C analysis
Briones M.J.I., Garnett M.H. and Piearce T.G. Soil Biology and
Biochemistry 2005 37/11 (2145-2149)
We report the first use of 14 C isotope analysis to investigate the
ecological grouping of earthworms. Mature endogeic (Allolobophora caliginosa), mature epigeic (Lumbricus rubellus), and
semimature anecic worms (A. longa) were collected in September 2002 from a woodland site at Lancaster, UK. Because anecic
worms are known to have a variable feeding behaviour and can
show dietary changes during ontogeny, additional immature and
mature specimens of A. longa were also collected from the same
site in January 2004. Epigeic earthworms showed the lowest
radiocarbon concentration (0-3-years old), implying that they assimilated more recently fixed carbon than the anecic or endogeic
earthworms. The age of carbon assimilated in mature anecic
species (5-7-years old) was closer to that of endogeic species (58-years old) than to epigeics, suggesting that a greater proportion
of older, more mineralised organic matter may form part of the
diet of the anecic earthworms than previously thought. These
results suggest that 14 C approaches are useful in the study of the
feeding behaviour of detritivorous animals by providing in situ
information on the age of the carbon assimilated by the worms.
This can then be related to their role in ecosystem functioning,
particularly in carbon cycling. В© 2005 Elsevier Ltd. All rights
reserved.
1798 Diversity of rhizobia isolated from an agricultural soil
in Argentina based on carbon utilization and effects of herbicides on growth
Zabaloy M.C. and GВґomez M.A. Biology and Fertility of Soils
2005 42/2 (83-88)
Seventy-six rhizobial isolates belonging to four different genera
were obtained from the root nodules of several legumes (Vicia
sativa, Vicia faba, Medicago sativa, Melilotus sp., Glycine max
and Lotus corniculatus). The action of five commonly used
herbicides [2,4-dichlorophenoxyacetic acid (2,4-D), glyphosate
(GF), dicamba, atrazine and metsulfuron-methyl] on the growth
of rhizobial strains was assessed. Subsequently, GF and 2,4D were tested in a minimum broth as C and energy sources
for 20 tolerant strains. The ability of these strains to metabolize
different carbon sources was studied in order to detect further differences among them. Tolerance of the bacteria to agrochemicals
varied; 2,4-D and GF in solid medium inhibited and diminished
growth, respectively, in slow-growing rhizobial strains. Among
slow-growing strains we detected Bradyrhizobium sp. SJ140
that grew well in broth + GF as the sole C and energy source.
No strain was found which could use 2,4-D as sole C source.
The 20 strains studied exhibited different patterns of C sources
utilization. Cluster analysis revealed three groups, corresponding
to four genera of rhizobia: Rhizobium (group I), Sinorhizobium
(group II) and Mesorhizobium-Bradyrhizobium (group III). On
the basis of the results obtained on responses to herbicides and C
sources utilization by the isolates investigated, it was possible to
differentiate them at the level of strains. These results evidenced
a considerable diversity in rhizobial populations that had not
been previously described for Argentinean soils, and suggested a
physiological potential to use natural and xenobiotic C sources.
344
SOILS
1799 Soil microbial biomass and activities in a Japanese Andisol as affected by controlled release and application depth
of urea
Chu H.Y., Hosen Y., Yagi K. et al. Biology and Fertility of Soils
2005 42/2 (89-96)
This experiment was conducted in maize field plots to study the
effects of controlled release and application depth of urea on soil
microbial biomass and activities at two depths of surface soil
of a Japanese Andisol from June to September, 2001. Three
N amendment treatments and a Control were included in this
experiment: deep application (8 cm) of controlled release urea;
deep application (8 cm) of conventional urea; surface application
of conventional urea; Control, without N application. Prior to
this experiment, the field plots received the same N fertilizer
treatments for two consecutive years under maize/barley rotation. Soil microbial biomass, dehydrogenase and nitrification
activities exhibited great vertical and temporal variations during
the maize growth season, and the microbial biomass was significantly correlated to soil water-filled pore space (p<0.01). N
fertilization did not significantly affect the microbial biomass, but
greatly increased the dehydrogenase and nitrification activities.
The increase in the microbial activities following N fertilization
was not attributed to the increase in microbial biomass but to the
increase in intrinsic microbial activities. Controlled release urea
was found to continuously affect the dehydrogenase activity over
a shorter distance, while conventional urea could greatly increase
the enzyme activity for a shorter period of time. Both controlled
release and deep application of urea had potentials to reduce
the nitrification activity and suggested that the nitrate production
might be decreased in 0-10 cm surface soil. Deep application
of urea increased aboveground N uptake by maize and then the
recovery rate of N fertilizer, whereas controlled release of urea
greatly increased grain yield and N uptake by grain.
1800 Spatial variation of soil enzyme activities and microbial
functional diversity in temperate alley cropping systems
Mungai N.W., Motavalli P.P., Kremer R.J. and Nelson K.A. Biology and Fertility of Soils 2005 42/2 (129-136)
Spatially dependent patterns in microbial properties may exist
in temperate alley cropping systems due to differences in litter
quality and microclimate in areas under trees compared to those
in the alleys. The effect of tree row location was evaluated for
its impact on soil enzyme activities and Biolog substrate use patterns. Soils were sampled to a depth of 30 cm at the tree row and
at the middle of the alley at two sites: a 21-year-old pecan (Carya
illinoinensis)/bluegrass (Poa trivials) intercrop (Pecan site) and a
12-year-old silver maple (Acer saccharinum)/soybean (Glycine
max)-maize (Zea mays) rotation (Maple site). Sampling was
done in fall 2001 and summer 2002. -Glucosidase activities,
Biolog patterns expressed as average well color (AWC), substrate
richness, and Shannon diversity index, and total Kjeldahl nitrogen (TKN) were significantly higher (P<0.05) in the tree row
than at the middle of the alley for surface soils at the Pecan site.
Fluorescein diacetate (FDA) hydrolytic activity was also higher
at the tree row for soils sampled in the fall, but did not differ
significantly for soils sampled in the summer. At the Maple
site, AWC and substrate richness were significantly higher at
the tree row for soils sampled in 2001. Soil volumetric water
content and temperature were generally lower in the tree row at
the Maple site. The results of this study suggest that functionally
different microbial populations may be present under pecan trees
compared to cropped alleys which may promote disparities in
nutrient availability necessitating differential long-term nutrient
management in such alley cropping systems.
1801 Population and behavioural level responses of arable
soil earthworms to boardmill sludge application
Butt K.R., Nieminen M.A., SirВґen T. et al. Biology and Fertility
of Soils 2005 42/2 (163-167)
The response of earthworms to soil application of boardmill waste
sludge was quantified in field and laboratory experiments. The
influence of one application of 6 104 tonnes ha-1 of unamended
sludge was tested against no application on silty-clay arable soil.
After 2 years, results in stubble-cultivated soil showed a 1.7 times
lower density of earthworms where sludge was added, whereas
there was no difference in average earthworm fresh weight. In
direct-drilled soil, there was an indication of lower average num-
bers of Lumbricus terrestris middens when sludge was applied.
Negative impacts in the field may have been due to indirect negative effects of the sludge application. In the laboratory, habitat
choice tests were undertaken with two common species from
the field site using sludge-based mulch and fertiliser products.
Aporrectodea caliginosa showed no discernible preference between soil and soil mixed with unamended sludge (mulch), but
favoured soil over soil mixed with sludge and chicken manure
(fertiliser). Tests with L. terrestris showed a similar pattern. The
preference of L. terrestris for the two products was compared
with that for chopped barley straw by direct observation of foraging behaviour. Differences in foraging time of L. terrestris for
different feeds were not significant, but mass of straw collected
was significantly greater compared with either type of sludge
treatment.
1802 Soil microbial indices as bioindicators of environmental changes in a poplar plantation
Moscatelli M.C., Lagomarsino A., Marinari S. et al. Ecological
Indicators 2005 5/3 (171-179)
An understanding of microbial biomass and microbial activity
as part of belowground processes as affected by elevated CO2 is
crucial in order to predict the long-term response of ecosystems
to climatic changes. The ratio of biomass C to soil organic C
(Cmic:Corg), the metabolic quotient (the specific soil respiration
of the microbial biomass, qCO2 ), the C mineralization quotient
(the fraction of total organic C mineralized throughout the incubation, qM), the microbial biomass change rate quotient (qC) and
soil inorganic nitrogen content were determined on soil samples
taken during 3 years (Fall 2000-Fall 2003) in a poplar plantation exposed to increased atmospheric CO2 by means of FACE
(Free Air CO2 Enrichment) technique and nitrogen fertilization.
A competition for nitrogen between plants and microrganisms,
stronger in FACE plots, induced a stress condition within microbial community. FACE treatment provided C for microbial
growth (Cmic:Corg), but reducing nitrogen availability, led to
a higher microbial loss over time (qC). Nitrogen fertilization
decreased microbial mortality lowering energetic maintenance
requirements (qCO2 ) and induced a short-term shift in favour of
microrganisms more rapid in the use of the resources. The C
mineralization quotient (qM) was not affected by either FACE
nor fertilization treatment meaning that the fraction of total organic carbon mineralized during the incubation period did not
vary significantly. В© 2005 Elsevier Ltd. All rights reserved.
1803 Distribution and diversity of soil protozoa in the
McMurdo Dry Valleys of Antarctica
Bamforth S.S., Wall D.H. and Virginia R.A. Polar Biology 2005
28/10 (756-762)
The polar desert soils of the McMurdo Dry Valley region support a limited water film community dominated by flagellates,
amoebae, and nematodes. This study describes the protozoa and
compares their distribution to nematodes. In 50 samples collected
from 12 locations, rotifers and tardigrades were infrequent, and
ciliates and testacea were rare. Soil protozoa occurred at all
sites but the dominant nematode, Scottnema lindsayae (Timm
1971), did not, indicating soil habitat factors limiting nematode
distribution are not limiting to protozoa. In contrast to the nematode species, which are all endemic to Antarctica, there were no
endemic protozoan morphospecies found in our samples. The
protozoan abundance was several orders of magnitude greater
than that of the nematodes, and the species diversity was much
greater. Most of the protozoa grew better at lower incubation
temperatures. The ubiquitous distribution of protozoa suggests
their importance in soil food webs and nutrient cycling in the dry
valleys. В© Springer-Verlag 2005.
1804 Invertebrate diversity under artificial cover in relation
to boreal forest habitat characteristics
Ferguson S.H. and Berube D.K.A. Canadian Field-Naturalist
2004 118/3 (386-394)
We investigated invertebrate diversity in boreal forests using an
experimental design that consisted of counting soil invertebrates
under artificial cover. The aim was to assess the utility of using
soil invertebrate diversity as a measure of ecosystem health. The
study area was grouped into five habitats: upland hardwood, low-
SOILS
land hardwood, conifer, shrub, and conifer-grass. SimpsonвЂ™s and
ShannonвЂ™s indices of invertebrate diversity were negatively correlated with percent herbaceous cover. Number of recognizable
taxonomic units (RTU richness) was negatively correlated with
percent litter cover. The number of individual invertebrates was
positively correlated with soil moisture and negatively correlated
with percent conifer cover. Invertebrate diversity varied among
habitat types, with conifer forests (spruce, fir, pine) having the
highest diversity and regenerating conifer-grass forests having
the lowest diversity, suggesting that successional stages affect diversity. The most productive sites, upland and lowland hardwood
habitats, had the highest abundance of soil invertebrates, although
intermediate diversity compared to the other five habitats. The
results are consistent with the view that diversity increases and
then decreases with productivity and disturbance over succession
(ca. 50-100 yr). Hence, maintenance of soil invertebrate diversity in managed boreal forests requires the provision of a varied
landscape with a mosaic of disturbance regimes.
1805 Linking species richness, biodiversity and ecosystem
function in soil systems
Coleman D.C. and Whitman W.B. Pedobiologia 2005 49/6 (479497)
Soils are the central organizing entities in terrestrial ecosystems
and possess extremely diverse prokaryotic and eukaryotic biota.
They are physically and chemically complex, with micro- and
macro-aggregates embedded within a solid, liquid and gaseous
matrix that is continually changing in response to natural and human-induced perturbations. Recent advances in molecular techniques in systematics have provided opportunities for the study of
biodiversity and biocomplexity of soil biota. A symposium and
workshop on soil biogeochemistry and biodiversity International
Symposium on Impacts of Soil Biodiversity on Biogeochemical
Processes in Ecosystems, Taiwan Forestry Research Institute,
Taipei, Taiwan April 18-24, 2004. Convened an international
array of participants working in biomes on virtually every continent on the planet (ranging from polar to tropical regions). This
special issue reports on the theoretical bases and applications
of molecular methods for the measurement of soil biodiversity.
Themes addressed include a melding of classical taxonomic investigations with biochemical fingerprinting and molecular probing of organism identities. Several papers highlight new advances
in identifications of prokaryotic and eukaryotic organisms. Examples include new developments in "fingerprinting" of microbes
active in "mycorrhizospheres" using immunocapture and other
innovative techniques. Developments in the study of impacts
of invasive plant and animal species on ecosystem function and
subsequent microbial community composition and function have
been very great in the last 2-3 years. Soils are major repositories
of legacies, including fine and coarse woody debris and other
organic products, which have feedbacks on soil diversity. The
ways in which species diversity and function of microbial and
faunal communities interact and their importance to ecosystem
function are examined in biological and biochemical detail. This
paper provides an overview of soil biodiversity and its feedbacks
on soil biogeochemical processes in ecosystems. В© 2005 Elsevier
GmbH. All rights reserved.
1806 Modeling trophic pathways, nutrient cycling, and dynamic stability in soils
Moore J.C., McCann K. and De Ruiter P.C. Pedobiologia 2005
49/6 (499-510)
Soil communities are compartmentalized into pathways of
trophic interactions and nutrient flows that originate from plant
roots, bacteria and fungi. The pathways differ in terms of the
organisms that comprise them, the habitats that the organisms occupy and the rates by which the organisms process and transfer
material and energy. The fungi, nematodes and arthropods within
the fungal pathway live in air-filled pore spaces and water films,
while the bacteria, protozoa, and nematodes within the bacterial
pathway occupy water-filled pore spaces and water films. Organisms within the fungal pathway have longer generation times
and process matter at slower rates than those within the bacterial
pathway. Empirical studies have shown that under natural conditions the pathways co-exist in a stable manner. The relative sizes
(indexed by the densities of organisms) and activities (indexed
by nutrient-flow rates, excretion rates and respiration rates) of
345
the pathways may change seasonally and in response to minor
disturbances, but they persist. However, large anthropogenic and
natural disturbances induce shifts in the relative sizes and activities of the pathways. Coincident with these shifts are reports
of changes in the aboveground plant community and the availability and retention of plant limiting nutrients. We developed
simple models of the bacterial and fungal pathways to explore the
consequences of the observed shifts on the dynamic stability of
the system. The more stable configurations occurred when there
was a balance in the flow of nutrients between the two pathways.
Large shifts in nutrient cycling and community structure towards
either the fungal pathway or toward the bacterial pathway resulted
in less stable or unstable configurations. В© 2005 Elsevier GmbH.
All rights reserved.
1807 Oribatid mite community structure and tree species
diversity: A link?
Kaneko N., Sugawara Y., Miyamoto T. et al. Pedobiologia 2005
49/6 (521-528)
Differences in tree species may lead to contrasting soil environments via differences in litter chemical quality and physical environmental factors, such as soil type and soil moisture. However,
separating the effects of litter quality and physical environment
is difficult under field conditions. Both litter quality and soil
environment affect the species composition of the soil animal
community. A diversity gradient of canopy tree species (11-25
species) located on homogeneous soil substrate at Tomakomai
Experimental Forest of Hokkaido University was used to analyse
the relationship between tree species diversity and oribatid mite
community structure. Soil samples were collected from three
levels of tree species richness (high, intermediate and low) with
three replicates each, in July 2000. Leaf area index (LAI) was
positively correlated with tree species diversity suggesting higher
litter input into the soils with increasing tree diversity. However,
the tree species diversity gradient affected neither accumulation
of litter on the forest floor nor abundance and species richness
of oribatid mites. Canopy and understory plant species richness, LAI, total soil carbon and biomass of epigeic and endogeic
earthworms did not significantly affect mite community structure
as indicated by redundancy analysis (RDA). The results suggest
that oribatid mite community structure is minimally affected by
tree species diversity and associated changes in litter diversity.
В© 2005 Elsevier GmbH. All rights reserved.
1808 Soil communities and plant litter decomposition as influenced by forest debris: Variation across tropical riparian
and upland sites
Ruan H., Li Y. and Zou X. Pedobiologia 2005 49/6 (529-538)
Forest debris on ground surface can interact with soil biota and
consequently change ecosystem processes across heterogeneous
landscape. We examined the interactions between forest debris
and litter decomposition in riparian and upland sites within a
tropical wet forest. Our experiment included control and debrisremoval treatments. Debris-removal reduced leaf litter decomposition rates in both the riparian and upland sites. Debris-removal
also reduced soil microbial biomass C in the upland site, but had
no effect on microbial biomass C in the riparian site. In contrast,
debris-removal altered the density of selected arthropod groups
in the riparian site. Litter decomposition rates correlated with
both soil microbial biomass and the density of millipedes in
a multiple stepwise regression model. Removal of forest debris
can substantially reduce rates of leaf litter decomposition through
suppressing soil activities. This influence can be further modified by landscape position. Forest debris plays an essential role
in maintaining soil activities and ecosystem functioning in this
tropical wet forest. В© 2005 Elsevier GmbH. All rights reserved.
1809 Plant litter decomposition influenced by soil animals
and disturbance in a subtropical rainforest of Taiwan
Hou P.- C.L., Zou X., Huang C.- Y. and Chien H.- J. Pedobiologia
2005 49/6 (539-547)
Soil fauna has been postulated as one of the paramount determinants of decomposition in the humid tropics. However, its effect
on litter decomposition has only been demonstrated in few forest
sites in Central America. In addition, landslide is a common
disturbance associated with heavy rainfall brought by tropical
346
SOILS
cyclones in the tropics and can potentially alter abundance and
structure of soil animals and thus affect litter decomposition. In
this study, we examined the effect of soil animals on litter decomposition in an Asian subtropical monsoon forest and compared
the animal effects in landslide-disturbed (2 years old) and undisturbed sites. Animal exclusion by naphthalene treatment significantly reduced the density and diversity of litterbag animals
and slowed down the rate of decomposition in both landslidedisturbed and undisturbed sites. However, density (per unit area)
and diversity of the litter animals and litter decomposition rate
did not differ between the landslide-disturbed and undisturbed
sites for both control and animal-excluded treatments. Our data
suggest that the abundance of soil animals is not limited by litter
mass. Furthermore, soil fauna recover quickly from landslides,
and faunaвЂ™s facilitative effect on litter decomposition is not altered
after their recovery. В© 2005 Elsevier GmbH. All rights reserved.
1810 Correlation between earthworms and plant litter decomposition in a tropical wet forest of Puerto Rico
Dechaine J., Ruan H., Sanchez- De Leon Y. and Zou X. Pedobiologia 2005 49/6 (601-607)
Earthworms are recognized to play an important role in the decomposition of organic materials. To test the use of earthworms
as an indicator of plant litter decomposition, we examined the
abundance and biomass of earthworms in relation to plant litter
decomposition in a tropical wet forest of Puerto Rico. We collected earthworms at 0-0.1 m and 0.1-0.25 m soil depths from
upland and riparian sites that represent the natural variation in
soils and decomposition rates within the forest. Earthworms
were hand-sorted and weighed for both fresh and dry biomass.
Earthworms were dominated by the exotic endogeic species Pontoscolex corethrurus MВЁuller; they were more abundant, and had
higher biomasses in the upland than in riparian sites of the forest.
Plant leaf litter decomposed faster in the upland than riparian
sites. We found that earthworm abundance in the upper 0.1 m
of the soil profile positively correlated with decomposition rate
of plant leaf litter. Ground litter removal had no effect on the
abundance or biomass of endogeic earthworms. Our data suggest
that earthworms can be used to predict decomposition rates of
plant litter in the tropical wet forest, and that the decomposition
of aboveground plant litter has little influence on the abundance
and biomass of endogeic earthworms. В© 2005 Elsevier GmbH.
All rights reserved.
1811 Seasonal dynamics of soil microbial biomass in coastal
sand dune forest
Chen T.- H., Chiu C.- Y. and Tian G. Pedobiologia 2005 49/6
(645-653)
Sand dunes are a typical landscape in the coast of western Taiwan,
where Casuarina forests were established decades ago to stabilize
sand dunes and protect the inland vegetation. Study of microbial
biomass in such an ecosystem may give insights into the role of
microbes in soil fertility and nutrient cycling. We established
our study sites in two topographic units based on elevation and
drainage types: upland and lowland. The study lasted for 2 years,
and soil samples were collected every 3 months. Microbial biomass C (C mic ) and N (Nmic ) were high in a shallow humic layer
that rested on top of the soil (1222-1319 mg kg-1 for Cmic and
245-276 mg kg-1 for Nmic ) and declined sharply to only one-tenth
of the above values in the underlying surface soil (0-10 cm depth).
Microbial biomass Cmic and Nmic in humic and surface soil were
not significantly different between upland and lowland sites. In
the upland soils, the mean Cmic was highest in autumn for both the
humic and surface soil, and lowest in spring and summer for the
humic layer and summer for the surface soil layer. In the lowland
soils, the Cmic was highest in winter for both humic and surface
soil, and lowest in spring and autumn for the humic layer and
spring and summer for surface soil. Strong fluctuations of Cmic
and Nmic were associated with the soil moisture prior to sampling,
which appeared to control the size of microbial biomass in this
environment. Temperature had little effect on the dynamics of
soil microbial biomass in the sand dune forest ecosystem. В©
2005 Elsevier GmbH. All rights reserved.
1812 Glomus intraradices dominates arbuscular mycorrhizal communities in a heavy textured agricultural soil
Mathimaran N., Ruh R., Vullioud P. et al. Mycorrhiza 2005 16/1
(61-66)
Arbuscular mycorrhizal fungal (AMF) spore communities were
surveyed in a long-term field fertilization experiment in Switzerland, where different amounts of phosphorus (P) were applied
to soil. Plots receiving no P as well as plots systematically
fertilized in excess to plant needs for 31 years were used to
test the hypothesis that application of P fertilizer changes the
composition and diversity of AMF communities. AMF spores
were isolated from the field soil, identified, and counted so as to
quantify the effect of P fertilization on AMF spore density, composition, and diversity. Trap cultures were established from field
soil with four host plants (sunflower, leek, maize, and Crotalaria
grahamiana), and the spore communities were then analyzed in
substrate samples from the pots. Altogether, nine AMF species
were detected in the soil. No evidence has been acquired for effect of P fertilization on spore density, composition, and diversity
of AMF in both the field soil and in trap cultures. On the other
hand, we observed strong effect of crop plant species on spore
densities in the soil, the values being lowest under rapeseed and
highest under Phacelia tanacetifolia covercrop. The identity of
plant species in trap pots also significantly affected composition
and diversity of associated AMF communities, probably due to
preferential establishment of symbiosis between certain plant
and AMF species. AMF spore communities under mycorrhizal
host plants (wheat and Phacelia in the fields and four host plant
species in trap pots) were dominated by a single AMF species,
Glomus intraradices. This resulted in exceptionally low AMF
spore diversity that seems to be linked to high clay content of the
soil. В© Springer-Verlag 2005.
1813 Oribatid mite (Acari, Oribatida) feeding on ectomycorrhizal fungi
Schneider K., Renker C. and Maraun M. Mycorrhiza 2005 16/1
(67-72)
The coexistence of a large number of soil animals without extensive niche differentiation is one of the great riddles in soil
biology. The main aim of this study was to explore the importance of partitioning of food resources for the high diversity of
micro-arthropods in soil. In addition, we investigated if ectomycorrhizal fungi are preferentially consumed compared to saprotrophic fungi. Until today, ectomycorrhizal fungi have never
been tested as potential food resource for oribatid mites. We offered six ectomycorrhizal fungi [Amanita muscaria (L.) Hook.,
Boletus badius (Fr.) Fr., Cenococcum geophilum Fr., Laccaria
laccata (Scop.) Fr., Paxillus involutus (Batsch) Fr. and Piloderma croceum J. Erikss. & Hjortstam], one ericoid mycorrhizal
fungus [Hymenoscyphus ericae (D.J. Read) Korf & Kernan] and
three saprotrophic fungi [Agrocybe gibberosa (Fr.) Fayod, Alternaria alternata (Fr.) Keissl. and Mortierella ramanniana (A.
MГёller) Linnem.] simultaneously to each of the mainly mycophagous oribatid mite species Carabodes femoralis (Nicolet),
Nothrus silvestris Nicolet and Oribatula tibialis Nicolet. The
ericoid mycorrhizal fungus H. ericae and the ectomycorrhizal
fungus B. badius were preferentially consumed by each oribatid
mite species. However, feeding preferences differed significantly
between the three species, with O. tibialis being most selective.
This study for the first time documented that oribatid mites feed
on certain ectomycorrhizal fungi. В© Springer-Verlag 2005.
1814 Effects of replacing natural secondary broad-leaved
forest with Cunninghamia lanceolata plantation on soil biological activities (Chinese)
Hu Y., Wang S., Yan S. and Gao H. Chinese Journal of Applied
Ecology 2005 16/8 (1411-1416)
This paper studied the effects of replacing natural secondary
broad-leaved forest with Cunninghamia lanceolata plantation in
the south, central and upstate areas of subtropical China on the
changes of soil chemical and biological properties. The results
showed that after replacing with Cunninghamia lanceolata plantation, the total organic carbon (TOC) content in surface soil
decreased by 31.51% - 58.24%, and the contents of soil total
N and P, pH value, C/N and C/P also decreased to different
degree. Soil microbial amount was less than that under natural
SOILS
secondary broad-leaved forest, soil urease, invertase, catalase
and dehydrogenase activities decreased, while soil polyphenol
oxidase activity increased by 8% - 40%. The respiration rate of
Cunninghamia lanceolata soil was 51.15% - 54.48% lower than
that of natural secondary broad-leaved forest soil. The correlation
between soil TOC and polyphenol oxidase activity was negative
(R = -0.723, n = 18), while those between soil TOC, N, P and
other enzyme activities were positive. It could be concluded
that replacing natural secondary broad-leaved forest with Cunninghamia lanceolata plantation worsened soil quality, and the
loss of soil organic matter in Cunninghamia lanceolata plantation
ecosystem might be one of the important factors resulted in the
decrease of soil nutrients and enzyme activities.
1815 Ecological distribution patterns of soil microbes under
artificial Eucalyptus Grandis stand (Chinese)
Feng J. and Zhang J. Chinese Journal of Applied Ecology 2005
16/8 (1422-1426)
In order to find out the ecological distribution patterns of soil
microbes under artificial Eucalyptus grandis stand, the amount
and distribution of soil bacteria, fungi and actinomycetes in Hongya County of Sichuan Province were investigated in 2004. The
results showed that soil microbial population under Eucalyptus grandis stand varied with seasons, being the maximum in
autumn, fewer in spring, and the minimum in summer. The
numbers were decreased in order of bacteria > actinomycetes
> fungi, which were mainly concentrated in 0-20 cm soil layer,
and rapidly decreased with increasing soil depth. In 0-60cm soil
layer, the numbers of aerobic bacteria were 0. 31 106 -14.39
106 , actinomycetes were 0.06 106 -0.79 106 , fungi were
0.06
106 -0.79
106 , and anaerobes were 0.05
106 -3.22
106 CFU g-1 . Comparing with artificial C. glauca stand and
farming land, Eucalyptus grandis stand had a larger number of
soil microbes, suggesting that Eucalyptus grandis, was benefit,
for soil microbial activity. The Simpson and Shannon-Wiener
index of the physiological groups of bacteria was 0.773 and
1.896, respectively.
1816 Main determinants of forest soil respiration along an
elevation/temperature gradient in the Italian Alps
Rodeghiero M. and Cescatti A. Global Change Biology 2005
11/7 (1024-1041)
The main determinants of soil respiration were investigated in 11
forest types distributed along an altitudinal and thermal gradient
in the southern Italian Alps (altitudinal range 1520 m, range in
mean annual temperature 7.8В°C). Soil respiration, soil carbon
content and principal stand characteristics were measured with
standardized methods. Soil CO2 fluxes were measured at each
site every 15-20 days with a closed dynamic system (LI-COR
6400) using soil collars from spring 2000 to spring 2002. At the
same time, soil temperature at a depth of 10 cm and soil water
content (m3 m-3 ) were measured at each collar. Soil samples were
collected to a depth of 30 cm and stones, root content and bulk
density were determined in order to obtain reliable estimates of
carbon content per unit area (kg Cm -2 ). Soil respiration and temperature data were fitted with a simple logistic model separately
for each site, so that base respiration rates and mean annual soil
respiration were estimated. Then the same regression model was
applied to all sites simultaneously, with each model parameter
being expressed as a linear function of site variables. The general
model explained about 86% of the intersite variability of soil respiration. In particular, soil mean annual temperature explained
the most of the variance of the model (0.41), followed by soil
temperature interquartlile range (0.24), soil carbon content (0.16)
and soil water content (0.05). В© 2005 Blackwell Publishing Ltd.
1817 Soil carbon and microbial communities at mitigated
and late successional bottomland forest wetlands
DвЂ™Angelo E.M., Karathanasis A.D., Sparks E.J. et al. Wetlands
2005 25/1 (162-175)
The practice of wetland mitigation has come into question during
the past decade because the relative capacity of the mitigated wetlands to perform normal wetland functions is mostly unknown. In
this study, we wanted to determine whether soil microbial communities were significantly different in early successional mitigated wetlands (<10 years) (ES) compared to late successional
bottomland hardwood forest wetlands (LS) due to differences in
347
soil properties, such as carbon quality and storage and waterholding capacity. Carbon storage in litter and soil was 1.5 times
greater in LS wetlands than ES wetlands. Soil water-holding
capacity was significantly greater in LS wetlands and was related
to soil organic C content (r2 =0.87, p-value=0.0007). Gravimetric water content was a moderately strong predictor of microbial
respiration (r2 =0.55-0.61, p-value=0.001-0.0004) and microbial
biomass (r2 =0.70, p-value=0.0019). Anaerobic microbial groups
were enriched in soils from LS wetlands in both the dry and wet
seasons, which suggested that LS soils were wetter for longer
periods of the year than ES soils. The capacity of these wetlands to support anaerobic microbial processes depends on soil
water retention characteristics, which were dictated by organic
matter content. As an integrator of microbial growth conditions
in soils, determination of microbial community composition by
phospholipid fatty acid (PLFA) analysis may be an important new
tool for monitoring successional development of compensatory
mitigation wetlands. В© 2005, The Society of Wetland Scientists.
Contamination and remediation
1818 A method of mercury removal from topsoil using lowthermal application
Kucharski R., Zielonka U., Sas- Nowosielska A. et al. Environmental Monitoring and Assessment 2005 104/1-3 (341-351)
Mercury contamination in the environment is problematic due
to the unusual physical properties and well-recognized toxicity
of this common metal. The bioavailability of mercury depends
strongly on its chemical speciation. Anthropogenic mercury
and its compounds appear in soil as "hot spots" located close to
industrial facilities that used or produced mercury. The nature
of the chemical production process, transportation and disposal
practices often determined the chemical composition and distribution of mercury in the surrounding soils. Current ex situ soil
remediation methods are expensive, produce undesirable side
effects to the environment and usually involve transportation of
contaminated soil. In this project, sponsored by the U.S. Department of Energy, a low-cost, simple approach to removing
mercury from soil was evaluated. The process uses low-temperature thermal desorption of volatile metallic mercury and its
compounds, and subsequent vapor capture. The project consisted of laboratory and plot-scale experiments. The laboratory
efforts evaluated theoretical calculations of mercury removal as
a function of time and temperature. The plot-scale experiment
was a practical application of the laboratory results. For both
experiments, mercury-polluted soil was obtained from a chemical production facility located in southern Poland. In laboratory
experiments, at temperature 373 K total mercury concentration
decreased in soil by nearly 32%. In plot-scale experiments, at
temperature 440 K, about 60-70% of total mercury was removed
from the soil. At the end of the experiment, a test of soil biological
activity was performed to check if the high temperature applied
to the soil did not impair the soil growth properties. There was
no negative effect of temperature found. В© Springer Science +
Business Media, Inc. 2005.
1819 The relative influence of distant and local (DEW-line)
PCB sources in the Canadian Arctic
Stow J.P., Sova J. and Reimer K.J. Science of the Total Environment 2005 342/1-3 (107-118)
Soil PCB contamination has been delineated at 18 of 21 Distant Early Warning Line (DEW-line) stations being cleaned up
by the Canadian Department of National Defence (DND). As a
result, detailed surface soil delineation data has been reported
for contamination exceeding 1 g/g (dw total Aroclor), which is
the remedial criteria for PCB contaminated soil under the DEWline cleanup project. The results of this delineation work has
allowed us to estimate the mass of PCB contained in surface soil
at these sites and to quantify the DEW-line as a source of PCBs
to both local and Arctic wide contamination. Our analysis of
DEW-line cleanup delineation reports suggests that pre-cleanup
surface soils (top 10 cm) with over 1 g/g PCB constituted a
source of PCBs that ranged from 0.8 to 43 kg with a mean
of 18 kg. The total mass of PCB at all 18 sites was 119 kg.
Previous studies have described a "halo-effect" that surrounds
348
SOILS
DEW-line sites, whereby PCB signatures in soil and plants up
to 10 km from source areas were attributed to the local source.
At Cambridge Bay (CAM-M), Nunavut, our inventory of PCB
sources and redistribution suggests that up to 3.4 kg of PCB
were exported from the site to the surrounding tundra prior to
cleanup. The primary mechanism of transportation appears to
be wind borne particulate. Potential vapour phase emissions of
PCB from contaminated soil at DEW-line sites appears to have
been negligible. Crown Copyright В© 2004 Published by Elsevier
B.V. All rights reserved.
1820 Filter pore size selection for characterizing dissolved
organic carbon and trihalomethane precursors from soils
Chow A.T., Guo F., Gao S. et al. Water Research 2005 39/7
(1255-1264)
Filters with a pore size of 0.45 m have been arbitrarily used for
isolating dissolved organic carbon (DOC) in natural waters. This
operationally defined DOC fraction often contains heterogeneous
organic carbon compounds that may lead to inconsistent results
when evaluating trihalomethane formation potential (THMFP).
A finer pore size filter provides more homogeneous DOC properties and enables a better characterization of organic matter.
In this study, we examined the effects of filter pore size (1.2,
0.45, 0.1 and 0.025 m) on characterizing total organic carbon,
ultra-violet absorbance at 254 nm (UV254 ) and THMFP of water
extracts from a mineral and organic soil in the Sacramento-San
Joaquin Delta, California. Results showed that the majority of
water extractable organic carbon (WEOC) from these soils was
smaller than 0.025 m, 85% and 57% in organic and mineral
soils, respectively. A high proportion of colloidal organic carbon
(COC) in mineral soil extracts caused water turbidity and resulted
in an abnormally high UV254 in 1.2 and 0.45 m filtrates. The
reactivity of organic carbon fractions in forming THM was similar for the two soils, except that COC from the mineral soil was
about half that of others. To obtain a more homogeneous solution
for characterizing THM precursors, we recommend a 0.1 m or
smaller pore-size filter, especially for samples with high colloid
concentrations. В© 2005 Elsevier Ltd. All rights reserved.
1821 Non-ionic surfactant flushing of pentachlorophenol
from NAPL-contaminated soil
Park S.- K. and Bielefeldt A.R. Water Research 2005 39/7 (13881396)
Column studies were conducted to assess the suitability of a
non-ionic surfactant Tergitol NP-10 (TNP10) for washing pentachlorophenol (PCP) from soil and non-aqueous phase liquids
(NAPLs). Flushing of 50 and 200 pore volumes of 5 g/L TNP10
was required to exhaust the surfactant sorption capacity of the
soil and soil plus NAPL, respectively. The sorption of surfactant to the soil in the columns was four times greater than the
quantity previously observed in batch tests. Flushing with 5 g/L
TNP10 removed 71-79% of the 200 mg/kg soil-sorbed PCP after
160 pore volumes compared to 0.7-2% PCP removal without
surfactant. In columns additionally containing 0.2% and 0.4%
PCP-contaminated heavy oil NAPL, the PCP removal efficiency
after flushing 200 pore volumes of 5 g/L TNP10 was nearly
100%. Therefore, removal of the PCP was more efficient in the
NAPL-containing columns, potentially due to competition of the
NAPL for PCP sorption sites. Rate-limited desorption of PCP
and TNP10 likely occurred. В© 2005 Elsevier Ltd. All rights
reserved.
1822 Influence of soil moisture on sunflower oil extraction
of polycyclic aromatic hydrocarbons from a manufactured
gas plant soil
Gong Z., Wilke B.- M., Alef K. and Li P. Science of the Total
Environment 2005 343/1-3 (51-59)
The influence of soil moisture on efficiency of sunflower oil extraction of polycyclic aromatic hydrocarbons (PAHs) from contaminated soil was investigated. The PAH-contaminated soil was
collected from a manufactured gas plant (MGP) site in Berlin,
Germany. Half of the soil was air-dried, and the other half
was kept as field-moist soil. Batch experiments were performed
using air-dried and field-moist soils, and sunflower oil was used
as extractant at oil/soil ratios of 2:1 and 1:1 (v/m). The experimental data were fitted to a first-order empirical model to
describe mass-transfer profiles of the PAHs. Column extraction
experiments were also conducted. Field-moist and air-dried soils
in the column were extracted using sunflower oil at an oil/soil
ratio of 2:1. In the batch experiments, PAHs were more rapidly
extracted from air-dried soil than from field-moist soil. Removal
rate of total PAH increased 23% at oil/soil ratio of 1:1 and 15.5%
at oil/soil ratio of 2:1 after the soil was air dried. The most favorable conditions for batch extraction were air-dried soil, with an
oil/soil ratio of 2:1. In the column experiments, the removal rate
of total PAH from air-dried soil was 30.7% higher than that from
field-moist soil. For field-moist soil, extraction efficiencies of
the batch extraction (67.2% and 81.5%) were better than that for
column extraction (65.6%). However, this difference between the
two methods became less significant for the air-dried soil, with
a total removal rate of 96.3% for column extraction and 90.2%
and 97% for batch extractions. A mass-balance test was carried
out for analytical quality assurance. The results of both batch
and column experiments indicated that drying the soil increased
efficiency of extraction of PAHs from the MGP soil. В© 2004
Elsevier B.V. All rights reserved.
1823 Persistent organic pollutants in soil density fractions:
Distribution and sorption strength
Krauss M. and Wilcke W. Chemosphere 2005 59/10 (1507-1515)
The sorption strength of persistent organic pollutants in soils
may vary among different soil organic matter (SOM) pools. We
hypothesized that polycyclic aromatic hydrocarbons (PAHs) and
polychlorinated biphenyls (PCBs) were unevenly distributed and
had different soil organic carbon (SOC)-water partition coefficients (KOC ) among soil density fractions. We determined the
concentrations and KOC values of 20 PAHs and 12 PCBs in bulk
samples and three density fractions (light, <2.0, medium, 2.02.4, and heavy, >2.4 g cm-3 ) of 11 urban topsoils (0-5 cm) from
Bayreuth, Germany. The KOC values were determined using sequential extraction with methanol-water mixtures (35% and 65%
methanol) at 60В°C. The sum of 20 PAH concentrations in bulk
soil ranged 0.4-186 mg kg-1 , and that of 12 PCB concentrations
1.2-158 g kg-1 . The concentrations of all PAHs and PCBs
decreased in the order light > medium > heavy fraction. When
normalized to the SOC concentrations, PAH concentrations were
significantly higher in the heavy than in the other density fractions. The KOC values of the PAHs in density fractions were 3-20
times higher than those of the PCBs with similar octanol-water
partition coefficients (KOW ). The KOC values of individual PAHs
and PCBs varied up to a factor of 1000 among the studied soils
and density fractions. The KOC values of 5- and 6-ring PAHs
tended to be highest in the heavy fraction, coinciding with their
enrichment in this fraction. For the other PAHs and all PCBs,
the K OC values did not differ among the density fractions. Thus,
there is no relationship between sorption strength and distribution
among density fractions, indicating that density fractionation is
not a suitable tool to distinguish among differently reactive PAH
and PCB pools in soils. В© 2005 Elsevier Ltd. All rights reserved.
1824 Extended X-ray absorption fine structure spectroscopy
evidence for the complexation of cadmium by reduced sulfur
groups in natural organic matter
Karlsson T., Persson P. and Skyllberg U. Environmental Science
and Technology 2005 39/9 (3048-3055)
It is widely accepted that the bioavailability, toxicity, and mobility
of trace metals are highly dependent on complexation reactions
with functional groups in natural organic matter (NOM). In this
study, the coordination chemistry of Cd in NOM was investigated
by extended X-ray absorption fine structure spectroscopy. Soil
organic matter (SOM) from different types of organic soils and
dissolved organic matter (DOM) from an organic and a mineral
soil horizon of a Spodosol and aquatic DOM from Suwannee
River were investigated. In SOM samples (1000-25000 g of
Cd g-1 , pH 4.6-6.6), Cd was coordinated by 1.0-2.5 S atoms at a
Вґ and by 3.0-4.5 0/N atoms at a distance
distance of 2.49-2.55 U
Вґ . In DOM samples (1750-4250 g of Cd g-1 , pH
of 2.22-2.25 U
5.4-6.3), Cd was coordinated by 0.3-1.8 S atoms at a distance of
Вґ and 3.6-4.5 0/N atoms at a distance of 2.23-2.26 U
Вґ.
2.51 -2.56 U
In both SOM and DOM samples a second coordination shell of
Вґ.
1.7-6.0 carbon atoms was found at an average distance of 3.12 U
This is direct evidence for inner-sphere complexation of Cd by
SOILS
functional groups in NOM. Furthermore, ion activity measurements showed that less than 1% of total Cd was in the form of
free Cd2+ in our samples. Bond distances and coordination numbers suggest that Cd complexed in SOM and DOM is a mixture
of a 4-coordination with S (thiols) and 4- and 6-coordinations
with 0/N ligands. Given that Cd-S associations on average are
stronger than Cd-O/N associations, our results strongly indicate
that reduced S ligands are involved in the complexation of Cd by
NOM also at native concentrations of metal in oxidized organicrich soils and in humic streams. В© 2005 American Chemical
Society.
1825 Sorption and related properties of the swine antibiotic
carbadox and associated N-oxide reduced metabolites
Strock T.J., Sassman S.A. and Lee L.S. Environmental Science
and Technology 2005 39/9 (3134-3142)
Carbadox (CBX) (methyl 3-[2-quinoxalinylmethylene]-carbazate N1, N4 dioxide) is a chemotherapeutic growth promoter
and antibacterial drug added to feed for starter pigs. Toxicity
of CBX and at least one of its metabolites (bisdesoxycarbadox;
DCBX) has resulted in a number of studies regarding its stability and residence time in edible swine tissue; however, little
is known on its environmental fate pertinent to the application
of antibiotic-laden manure to agricultural fields. We measured
sorption of CBX and DCBX by soils, sediment, and homoionic
clays from 10 mM KCl and 5 mM CaCl2 solutions, sorption of
two N-oxide reduced metabolites (N4 and N1) by a subset of
soils from 5 mM CaCl2 , octanol - water partition coefficients
(K ow ) of CBX and all three metabolites, and CBX solubility
in water and mixed solvents. Sorption appeared well-correlated
to organic carbon (OC) for the soils (e.g., log (Koc , L/kg OC)
= 3.96 0.18 for CBX). However, sorption was enhanced in
the presence of K+ , competitive sorption from the metabolites
was observed, and sorption by clay minerals was large ( 105
L/kg for SWy-1). Sorption by clays was inversely correlated to
surface charge density (e.g., sorption decreased from 10 5 to 10
L/kg as charge density increased from 1 to 2 mol c /m2 ), similar
to what has been observed for nitroaromatic compounds. In the
absence of a clay surface, hydrophobic-type forces dominated
with Kow values and reverse-phase Chromatographic retention
times increasing with the loss of oxygen from the aromatic nitrogens. Therefore, it is likely that both OC and clay contribute
significantly to sorption of carbadox and related metabolites by
soils with relative contributions most dependent on clay type. В©
2005 American Chemical Society.
1826 Influence of smectite hydration and swelling on atrazine sorption behavior
Chappell M.A., Laird D.A., Thompson M.L. et al. Environmental
Science and Technology 2005 39/9 (3150-3156)
Smectites, clay minerals commonly found in soils and sediments,
vary widely in their ability to adsorb organic chemicals. Recent
research has demonstrated the importance of surface charge density and properties of exchangeable cations in controlling the
affinity of smectites for organic molecules. In this study, we
induced hysteresis in the crystalline swelling of smectites to test
the hypothesis that the extent of crystalline swelling (or interlayer
hydration status) has a large influence on the ability of smectites
to adsorb atrazine from aqueous systems. Air-dried K-saturated
Panther Creek (PC) smectite swelled less (d(001) = 1.38 nm)
than never-dried K-PC (d(001) = 1.7 nm) when rehydrated in
20 mM KCl. Correspondingly, the air-dried-rehydrated K-PC
had an order of magnitude greater affinity for atrazine relative to
the never-dried K-PC. Both air-dried-rehydrated and never-dried
Ca-PC expanded to approximately 2.0 nm in 10 mM CaCl2 and
both samples had similar affinities for atrazine that were slightly
lower than that of never-dried K-PC. The importance of interlayer
hydration status in controlling sorption affinity was confirmed
by molecular modeling, which revealed much greater interaction
between interlayer water molecules and atrazine in a three-layer
hydrate relative to a one-layer hydrate. The entropy change on
moving atrazine from a fully hydrated state in the bulk solution to
a partially hydrated state in the smectite interlayers is believed to
be a major factor influencing sorption affinity. In an application
test, choice of background solution (20 mM KCl versus 10 mM
CaCl2 ) and air-drying treatments significantly affected atrazine
sorption affinities for three-smectitic soils; however, the trends
349
were not consistent with those observed for the reference smectite. Further, extending the initial rehydration time from 24 to
240 h (prior to adding atrazine) significantly decreased the soilвЂ™s
sorption affinity for atrazine. We conclude that interlayer hydration status has a large influence on the affinity of smectites for
atrazine and that air-drying treatments have the potential to modify the sorption affinity of smectitic soils for organic molecules
such as atrazine. В© 2005 American Chemical Society.
1827 Pot and field studies on bioremediation of p-nitrophenol contaminated soil using Arthrobacter protophormiae
RKJ100
Labana S., Pandey G., Paul D. et al. Environmental Science and
Technology 2005 39/9 (3330-3337)
Biodegradation of p-nitrophenol (PNP), a priority pollutant, was
studied as a model system for bioremediation of sites contaminated with nitroaromatic/organic compounds. Bioremediation
of PNP-containing soil was first carried out in pots using immobilized and free cells of Arthrobacter protophormiae RKJ100 in
order to ascertain the role of a suitable carrier material. Results
showed that stability of the introduced strain was enhanced upon
immobilization and that the rate of PNP depletion decreased
with increasing depth of soil. Small-scale field studies (in one
square meter plots) were then conducted in which PNP-contaminated soil from an agricultural field was bioaugmented with
strain RKJ100 under natural environmental conditions. PNP
was totally depleted in 5 days by immobilized cells, whereas free
cells were able to deplete 75% of PNP in the same time period.
The fate of the released strain as monitored by plate counts,
hybridization studies, and real-time polymerase chain reaction
revealed fairly stable population of the cells upon immobilization on corncob powder throughout the period of study. В© 2005
American Chemical Society.
1828 Influence of dissolved organic matter from waste material on the phytotoxicity and environmental fate of triflusulfuron methyl
Gigliotti G., Onofri A., Pannacci E. et al. Environmental Science
and Technology 2005 39/19 (7446-7451)
Bioassays and chemical analyses were performed to study the
effect of hydrophobic dissolved organic matter (HoDOM) extracted from a municipal waste compost (MWC) on the behavior of triflusulfuron methyl in soil and water. Bioassays with
oilseed rape showed that HoDOM in culture solution lowered
the effective dose 50 of triflusulfuron methyl by up to 4.8 times.
Equilibrium dialysis experiments showed that in aqueous solution triflusulfuron methyl was adsorbed to HoDOM (KOC of
446.5 mL g-1 ). The half-life in water (pH 7.0) was increased
from 52 to 76 days in the presence of HoDOM, but this cannot
completely explain its phytotoxicity, as bioassays lasted for 21
days only. On the other hand, the addition of HoDOM to soils
did not change the degradative behavior of triflusulfuron methyl.
Fluorescein diacetate hydrolysis showed that HoDOM in soil
did not significantly influence soil microbial activity, which may
explain the above result on degradation in soil. Furthermore, in
batch equilibrium experiments on soil, triflusulfuron methyl was
only weakly adsorbed and the presence of HoDOM significantly
modified the isotherm form. Results suggest that although the
addition of exogenous HoDOM from MWC to soil did not influence the herbicideвЂ™s persistence, its enhanced mobility could be
of environmental concern and may deserve further research. В©
2005 American Chemical Society.
1829 Assessing sequestration of selected polycyclic aromatic
hydrocarbons by use of adsorption modeling and temperature-programmed desorption
Abu A. and Smith S. Environmental Science and Technology
2005 39/19 (7585-7591)
Sequestration of phenanthrene and pyrene was investigated in
two soils-a sandy soil designated SBS and a silt-loam designated
LHS-by combining long-term batch sorption studies with thermal
desorption and pyrolysis of amended soil samples. The Polanyibased adsorption volume and the adsorbed solute mass increased
with aging for both soils, thus demonstrating the mechanism for
observed sequestration. Despite rigorous thermal analysis, 3062% (SBS sand) and 8-30% (LHS silt-loam) of phenanthrene
350
SOILS
could not be recovered after 30-270 days of sorption, with the
increase in desorption resistance showing greater significance in
SBS sand. For both soils, these values were 20-65% of adsorbed
phenanthrene mass. Activation energies estimated from the temperature-programmed desorption (TPD) of sorbed phenanthrene
at 375 В°C were 51-53 kJ/mol, consistent with values derived
for desorption of organic compounds from humic materials. The
activated first-order model fitting of observed TPD data supports
the conclusion that the desorption-resistant fraction of phenanthrene has become sequestered onto condensed organic domains
and requires temperatures exceeding 600 В°C to be released. The
work demonstrates the use of thermal analysis in complementing
the Polanyi-based adsorption modeling approach for assessing
the mechanistic basis for sequestration of organic contaminants
in soils. В© 2005 American Chemical Society.
1830 Model testing for the remediation assessment of a radium contaminated site in Olen, Belgium
Sweeck L., KanyВґar B., Krajewski P. et al. Journal of Environmental Radioactivity 2005 84/2 (245-258)
Environmental assessment models are used as decision-aiding
tools in the selection of remediation options for radioactively
contaminated sites. In most cases, the effectiveness of the remedial actions in terms of dose savings cannot be demonstrated
directly, but can be established with the help of environmental
assessment models, through the assessment of future radiological
impacts. It should be emphasized that, given the complexity of
the processes involved and our current understanding of how they
operate, these models are simplified descriptions of the behaviour
of radionuclides in the environment and therefore imperfect. One
way of testing and improving the reliability of the models is to
compare their predictions with real data and/or the predictions
of other models. Within the framework of the Remediation
Assessment Working Group (RAWG) of the BIOMASS (BIOsphere Modelling and ASSessment) programme coordinated by
IAEA, two scenarios were constructed and applied to test the
reliability of environmental assessment models when remedial
actions are involved. As a test site, an area of approximately 100
ha contaminated by the discharges of an old radium extraction
plant in Olen (Belgium) has been considered. In the first scenario, a real situation was evaluated and model predictions were
compared with measured data. In the second scenario the model
predictions for specific hypothetical but realistic situations were
compared. Most of the biosphere models were not developed to
assess the performance of remedial actions and had to be modified
for this purpose. It was demonstrated clearly that the modellerвЂ™s
experience and familiarity with the mathematical model, the site
and with the scenario play a very important role in the outcome of
the model calculations. More model testing studies, preferably
for real situations, are needed in order to improve the models and
modelling methods and to expand the areas in which the models
are applicable. В© 2005 Elsevier Ltd. All rights reserved.
1831 A comparison of five pesticides adsorption and desorption processes in thirteen contrasting field soils
Boivin A., Cherrier R. and Schiavon M. Chemosphere 2005 61/5
(668-676)
Batch adsorption and desorption experiments were performed
using thirteen agricultural soil samples and five pesticides. Experimental data indicated a gradient in pesticide adsorption on
soil: trifluralin 2,4-D > isoproturon > atrazine bentazone.
Atrazine, isoproturon and trifluralin adsorption were correlated
to soil organic matter content (r2 = 0.7, 0.82, 0.79 respectively).
Conversely, bentazone adsorption was governed by soil pH (r2
= 0.68) while insignificant effect has been shown in the case of
2,4-D. Multiple linear regressions were used to combine relationships between the various soil parameters and the Freundlich
adsorption coefficient (K f ) of each pesticide. Then desorption
was assessed since it may reflect some of the interactions involved between the pesticides and the soil components. Adsorbed molecules were released into aqueous solution in the
following order: bentazone
atrazine > isoproturon > 2,4D
trifluralin. The occurrence of hysteresis did not allow an
accurate interpretation of the pesticide desorption data because
of the possible interplay of several processes. В© 2005 Elsevier
Ltd. All rights reserved.
1832 Enhancement of PAH biomineralization rates by cyclodextrins under Fe(III)-reducing conditions
Ramsay J.A., Robertson K., VanLoon G. et al. Chemosphere
2005 61/5 (733-740)
Amendment of a soil slurry with low concentrations of a cyclodextrin, hydroxypropyl- -cyclodextrin (HPCD), (0.05-0.5 g
l-1 ) increased the phenanthrene mineralization rate of a microbial
consortium by 25% under Fe(III)-reducing conditions. Although
a higher concentration (5.0 g l -1 ) resulted in a faster initial rate
of mineralization, mineralization ceased after 25 days with maximum mineralization 17% lower than the control (no HPCD). At
lower HPCD concentrations, mineralization was still taking place
at day 76. Although pH should affect Fe(III) solubility, mineralization rates at pH 6.0 and 8.0 were comparable. Decreasing the
temperature reduced the extent and rate of mineralization, but
mineralization rates at 10В°C were still 60% of that obtained at
30В°C. В© 2005 Elsevier Ltd. All rights reserved.
1833 Remediation of contaminated soils using supercritical
fluid extraction: A review (1994-2004)
SaldaЛњna M.D.A., Nagpal V. and Guigard S.E. Environmental
Technology 2005 26/9 (1013-1032)
Considerable effort is being made to remediate soils contaminated with petroleum hydrocarbons, polyaromatic hydrocarbons,
polychlorinated biphenyls, dioxins, heavy metals and other organic and inorganic compounds that have resulted from industrial
activities, accidental spills and improper waste disposal practices. Current remediation technologies may be limited when
treating certain types of contaminated soils and therefore new,
efficient and cost effective technologies are being investigated.
Supercritical fluid extraction is a potential remediation technology for contaminated soils. It is a simple, fast and selective
solvent extraction process that uses a supercritical fluid as the
solvent. A commonly used fluid is carbon dioxide at pressures
and temperatures greater than 7.4 MPa and 31В°C, respectively. In
supercritical fluid extraction, the extracted contaminants first dissolve into the supercritical solvent and then these contaminants
are separated from the supercritical solvent via a simple change in
pressure and temperature conditions or by using a separation process. This paper provides a review of supercritical fluid extraction
and its application to the remediation of contaminated soils. This
review focuses on the removal of organic contaminants (such as
petroleum hydrocarbons, polyaromatic hydrocarbons, polychlorinated biphenyls and others) and inorganic contaminants (such
as heavy metals and radioactive elements) from soils. Recent
data (1994-2004) on the supercritical fluid extraction of spiked
soils and field-contaminated soils were collected. The success
of supercritical fluid extraction as a method for removing these
contaminants from soils is highlighted and some of the future
research needed to develop it as a commercial-scale economic
remediation technology are discussed. В© Selper Ltd., 2005.
1834 Lead and zinc extraction potential of two common crop
plants, Helianthus annuus and Brassica napus
Solhi M., Shareatmadari H. and Hajabbasi M.A. Water, Air, and
Soil Pollution 2005 167/1-4 (59-71)
Phytoextraction is a remediation technology that uses plants to
remove heavy metals from soil. The success of a phytoextraction
process depends on adequate plant yield (aerial parts) and high
metal concentrations in plant shoots. A pot experiment was
conducted to investigate the combination effects of plants [sunflower (Helianthus annuus) and canola (Brassica napus)] with
soil treatments (manure, sulfuric acid and DTPA). Treatments,
including two plants and seven soil treatments, which applied
according to completely randomized factorial design with three
replications. The largest shoot dry weight biomass production
occurred in manure treatments for both plants. The maximum
shoot concentrations of Pb and Zn were 234.6 and 1364.4 mg kg-1
respectively in three mmoles DTPA kg-1 treatment of sunflower.
Furthermore the results showed that sunflower had a higher extracting potential for removal of Pb and Zn from polluted soil. В©
Springer 2005.
SOILS
1835 Effects of low molecular weight organic anions on the
release of arsenite and arsenate from a contaminated soil
Zhang S., Li W., Shan X.- Q. et al. Water, Air, and Soil Pollution
2005 167/1-4 (111-122)
Low-molecular-weight-organic-anions (LMWOAs) are important exudates of plants and may influence the mobility and bioavailability of metals or metalloids. In the present study the
effects of selected LMWOAs, citrate, malate and oxalate, on the
release of arsenite (As(III)) and arsenate (As(V)) in a contaminated soil were investigated. The organic anions have significant
influence upon the release of arsenic from the soil, and a linear
relationship exits between the released arsenic and the concentration of LMWOAs in the extractants. pH effects on the arsenite
and arsenate adsorption were not significant over the range from
3 to 7. The amounts of arsenite and arsenate released were significantly correlated with the release of Fe, Mn and Al, suggesting
that arsenic was mainly released from Fe-, Mn- and Al-oxides or
hydroxides in soil. The ratio of released arsenite to arsenate was
not influenced by LMWOAs. В© Springer 2005.
1836 Potentially mobile lead fractions in montane organicrich soil horizons
Kaste J.M., Friedland A.J. and Miller E.K. Water, Air, and Soil
Pollution 2005 167/1-4 (139-154)
Anthropogenic emissions during the 20th century resulted in
global lead (Pb) contamination of soils. Recent studies have
demonstrated that the organic horizons of temperate montane
Spodosols in the northeastern United States retain Pb on timescales of 50 to 150 years. The precise mechanism(s) of this strong
Pb partitioning to organic-rich soil material remain elusive, but
a detailed understanding of Pb retention by organic layers and
mineral topsoils is critical for predicting the fate of pollutants
deposited on ecosystems. Here we use selective extractions to
quantify potentially mobile pools of Pb in the surface horizons of
relatively remote montane Spodosols from New Hampshire and
Vermont. Using 10 consecutive rinses of water, we extracted a
total of 1 to 5% of the carbon, and 4 to 12% of the Pb. Dialysis
equilibration experiments demonstrate that this Pb is >5,000
molecular weight, and not truly dissolved as Pb 2+ . When soil
was extracted with a single rinse of 0.02 M HCl (pH 1.7), 5 to
11% of the Pb was mobilized. However, hydroxylamine hydrochloride in 0.02 M HCl (a reducing agent) extracted 30 to 40%
of the Pb. Repeated rinses with sodium hydroxide and sodium
pyrophosphate, which target organic matter but may extract other
soil phases removed 16 to 75% and 60 to 100% of the Pb, respectively. We show that significant Fe, Pb, and Al can be released
from soils under reducing conditions, and that this fraction can
be underestimated if sodium pyrophosphate is used in a previous
step for leaching the organic-metal phase, as is typically done
in sequential extraction schemes. Our results indicate that inorganic phases play an important role in determining Pb mobility
and bioavailability, even in surface soil horizons dominated by
organic matter. В© Springer 2005.
1837 Aspergillus tubingensis reduces the pH of the bauxite
residue (red mud) amended soils
Krishna P., Reddy M.S. and Patnaik S.K. Water, Air, and Soil
Pollution 2005 167/1-4 (201-209)
Bauxite residue (red mud), a poor substrate for plant growth
because of very high pH, salinity and sodicity, is required to
be revegetated. The possibility of using Aspergillus tubingensis (AT1), a phosphate solubilizer in red mud amended soils to
reduce the alkalinity of the red mud was studied in the present
study. A. tubingensis was tested for its ability to grow at high pH
and in different concentrations of aluminium (Al), iron (Fe) and
sodium (Na). The results showed that A. tubingensis was able to
grow at high pH and reduce the alkalinity of the nutrient medium
and also to accumulate different metals in the mycelium. The
pH values of the red mud amended soils were also significantly
reduced (by 2-3 units) by A. tubingensis, which resulted in maize
growth improvement. These results suggest that A. tubingensis
plays an important role in reducing the pH of the red mud and
also helps in promoting the plant growth in it. В© Springer 2005.
351
1838 Comparison of plants for germination toxicity tests in
petroleum- contaminated soils
Banks M.K. and Schultz K.E. Water, Air, and Soil Pollution 2005
167/1-4 (211-219)
Pollution of soil by petroleum hydrocarbons is a serious environmental problem world-wide. Although total concentration of
contaminants in soil and/or water is used for regulatory review,
it also is beneficial to assess the potential for ecosystem impact
through a series of bioassays. One commonly used bioassay is
seed germination. In this test, seeds are placed in contaminated
material, and seedlings enumerated after a specified incubation
period. However, different plant species produce variability in
response. In the research project reported here, lettuce (Lactuca
sativa L.), millet (Panicum miliaceum), radish (Raphanus L.),
red clover (Trifolium pratense L.), and wheat (Triticum aestivum) were tested for sensitivity to petroleum-contaminated soil
in germination tests. While most plants appeared to show some
sensitivity to the pollutant, only lettuce had a statistically significant difference in response to contaminated and uncontaminated soil. These results confirm that Latuca sativa L is the
optimal plant choice for standard germination toxicity tests with
petroleum-impacted soil. В© Springer 2005.
1839 Influence of water content and plants on the dissipation
of chlorinated volatile organic compounds in soil
Cho C., Sung K., Coapcioglu M.Y. and Drew M. Water, Air, and
Soil Pollution 2005 167/1-4 (259-271)
To devise effective procedures for the remediation of soil contaminated by VOCs, an improved understanding of their fate and
transport mechanisms in soil is essential. To show the effect
of plants on the dissipation of 1,1,1-trichloroethane (TCA), trichloroethylene (TCE) and tetrachloroethylene (PCE), two types
of experiments, vial and column, were conducted. The results
suggested that keeping the soil moisture content at field capacity
is desirable for VOCs dissipation. All VOCs were dissipated
quickly in unplanted columns than planted conditions in early
periods of the experiment because more volatilization occurred
in unplanted conditions. The plants could take up and retard
volatile contaminants, and prevent contamination of ambient air.
Although the time for acclimation for microbial communities
to contaminants for enhanced biodegradation should be considered, phytoremediation is potentially a cost-effective remediation
technique for soils contaminated by volatile organic compounds
(VOCs). В© Springer 2005.
1840 Application of Relaxed Eddy Accumulation technique
to quantify Hg 0 fluxes over modified soil surfaces
Olofsson M., Sommar J., LjungstrВЁom E. et al. Water, Air, and
Soil Pollution 2005 167/1-4 (331-352)
Fluxes of mercury from a waste repository and from an agricultural field amended with sewage sludge were measured. The
measurements were performed by utilising a Relaxed Eddy Accumulation (REA) system synchronously coupled to automated
mercury cold vapour atomic fluorescence analysers (CVAFA).
The waste repository was severely contaminated and fluxes of
between 0.16 g m -2 h-1 and 29 g m-2 h-1 could be measured.
Fluxes at the slightly contaminated agricultural field measured
between 8 ng m-2 h-1 and 1.9 g m-2 h -1 . The results showed
that the REA-CVAFA system could be used for measurements
above both severely-and slightly contaminated soils. The measurements at the chlor-alkali plant showed that temperature was
the most important parameter controlling the release of mercury
at this site. At the agricultural field, the measurements indicated
that both solar radiation and temperature may have influenced
the emissions. Most of the mercury added to the field was lost to
the atmosphere during the summer season. В© Springer 2005.
1841 An empirical model for estimating remediation costs
at contaminated sites
Kaufman M.M., Rogers D.T. and Murray K.S. Water, Air, and
Soil Pollution 2005 167/1-4 (365-386)
A model for estimating the remediation costs at contaminated
sites is developed, in which the predictor variable is a composite
of surface, subsurface, and contaminant risk factors. Calibration
of the model is performed at 83 sites in an urbanized watershed
with diverse surface geology in southeastern Michigan. These
352
SOILS
test sites exhibited different extents of contamination, including some where only soil was contaminated, and others where
soil and groundwater were contaminated. The model was then
applied to 79 sites with multiple contamination extents within
different watersheds in North America, Europe, Australia, and
Africa. The results indicate a very high correlation between
the estimated and actual remediation costs at these sites. This
model thus has the potential for providing reliable estimates of
remediation costs across a broad array of soil and groundwater
contamination scenarios, including dense nonaqueous phase liquid (DNAPL) contamination in sandy soil and lead in clay soil.
В© Springer 2005.
1842 The influence of organic ligands on the retention of
lead in soil
Schwab A.P., He Y. and Banks M.K. Chemosphere 2005 61/6
(856-866)
Organic acids are commonly produced and exuded by plant roots
and soil microorganisms. Some of these organic compounds
are effective chelating agents and have the potential to enhance
metal mobility. The effect of citrate and salicylate on the leaching of lead in soil was investigated in a laboratory experiment.
In short-term batch experiments, adsorption of lead to soil was
slightly enhanced with increasing salicylate concentration (5005000 M) but decreased significantly in the presence of citrate.
These observations suggested that citrate may enhance Pb leaching, but this was not observed in the column study. Soluble Pb
in the presence and absence citrate or salicylate (up to 5000 M)
was added to soil columns at a moderate flow rate, but no Pb
was observed to emerge from the soil in any of the soil columns.
Rapid biodegradation of citrate in soil eliminated potential complexing ability. Breakthrough of Pb from soil was noted only
when using small columns at high flow rates (>20 pore volumes
per day). Under these conditions of physical and chemical nonequilibrium, citrate was not degraded and significantly enhanced
Pb mobility. As in the batch adsorption experiments, the presence
of salicylate reduced Pb leaching. Considering the extreme conditions required to induce Pb leaching, it is likely that Pb will
remain relatively immobile in soil even in the presence of a strong
complexing agent such as citrate. В© 2005 Elsevier Ltd. All rights
reserved.
1843 Effects of Lumbricus terrestris, Allolobophora chlorotica and Eisenia fetida on microbial community dynamics
in oil-contaminated soil
Schaefer M., Petersen S.O. and Filser J. Soil Biology and Biochemistry 2005 37/11 (2065-2076)
Oil spills are one of the most common types of soil pollution. Bioremediation has become an attractive alternative to physicochemical methods of remediation, where feasible. Earthworms have
been shown to stimulate the degradation of petroleum hydrocarbons in soil, and it was hypothesized that the role of earthworms
in remediation lies in the enhancement of an oil degrading microbial community. The aim of this study was to characterize
microbial activity and community dynamics in oil-contaminated
soil incubated with or without earthworms. Three earthworm
species (Eisenia fetida, Allolobophora chlorotica and Lumbricus
terrestris) were incubated in crude oil polluted soil (ca. 10,000
mg/kg total petroleum hydrocarbons (TPH)) and a reference soil
for 28 d. Control treatments with manual mixing and/or cattle dung amendment were also included. In the oil-contaminated soil, respiration and concentration of microbial biomass
was significantly enhanced by earthworm amendment, and TPH
concentrations decreased significantly. These effects were less
evident in treatments with A. chlorotica, possibly due to a difference in behavior, since individuals of this endogeic species were
found in a state of inactivity (aestivation). Microbial community
dynamics were described by phospholipid fatty acid (PLFA) analyses. After 28 d, similar shifts in the soil PLFA composition
were observed in the oil-contaminated soil irrespective of worm
species. Fungal:bacterial ratios were increased in the presence of
worms, but also by addition of dung as a food source, indicating
a non-specific effect of metabolizable substrates. In contrast,
the fatty acids 17:1! 8 (= 9-heptadecenoic acid) and 20:4! 6c
(arachidonic acid) were specifically stimulated by the presence
of earthworms in the oil-contaminated soil. The results showed
that earthworms can contribute positively to bioremediation of
oil-contaminated soil, but that the effect may be species-dependent. В© 2005 Elsevier Ltd. All rights reserved.
1844 Influence of flooding on the degradation of linuron,
isoproturon and metolachlor in soil
Accinelli C., Screpanti C. and Vicari A. Agronomy for Sustainable Development 2005 25/3 (401-406)
Degradation of pesticides in soil usually refers to normally aerated conditions. However, considering that under some circumstances, fields treated with pesticide can be subject to flooding
phenomena, more information on pesticide persistence under
these conditions is needed. The main objective of the present
study was to investigate the persistence of linuron, isoproturon
and metolachlor in soil samples incubated under flooding conditions. During the whole incubation period, changes in soil Eh, pH
and microbial C were measured. Flooding conditions produced
different effects on the persistence of the three herbicides. More
specifically, flooding conditions led to a significant increase in
linuron and isoproturon persistence. The half-lives of linuron
and isoproturon in flooded soil were 1.8 and 1.4 times higher
than in nonflooded soil, respectively. An opposite phenomenon
was observed with metolachlor. The half-life of metolachlor was
reduced from 32.2 to 24.1 days in nonflooded and flooded soil,
respectively. Soil Eh rapidly decreased in soil samples incubated
under flooding conditions, passing form 368.0 mV to - 225.5
mV within the first week of flooding. No significant changes in
soil microbial C in soil samples incubated under the two water
regimes were observed. The results obtained from the present
experiment showed that information from normally aerated soil
conditions is not correctly applicable to predict herbicide persistence under flooding conditions. В© INRA, EDP Sciences,
2005.
1845 Nitrogen mineralization in mine waste-contaminated
soils
Arslan H., GВЁuleryВЁuz G., Kirmizi S. and GВЁucВёer SВё. Fresenius
Environmental Bulletin 2005 14/10 (900-906)
In this study, the effect of mine wastes on nitrogen mineralization
was investigated at two different depths of soil (0-5 cm and 5-15
cm) in waste sites in the surroundings of the Etibank Wolfram
Mine Work, Bursa, Turkey. Due to the disorder of the distribution
of mining wastes, the pH, CaCO3 % and element content (Fe, Mn,
Zn, Mg) in the soils around the mine were enriched by mining
activity. The investigation was carried out in soils taken from
waste-removal pools (WRPs) and from selected sample sites
which differed in their distances from the mine works. Waste
materials resulted by mining were discharged with water and,
they were fall down on two waste removal pools which were
constructed as primitive terraces around the mine work. For
this reason, elements were most enriched on sandy ground of
abandoned pools. Both N-mineralization and nitrification were
determined by a standard incubation method under laboratory
conditions at 20В°C and 60 % WHC. Mineral nitrogen was analyzed at the initial, the 21st and the 63rd day by micro-distillation
method. The net mineral N production was estimated for 21 and
42 days. It was calculated as the potential mineralization rate of
organic nitrogen. N-mineralization and net production were the
highest at the site furthest from the mine waste site. Significant
negative correlations between nitrification and element contents
(Fe, Zn, Mn, Mg) of soils were also found. This shows that the
mine wastes have a negative effect on the nitrogen mineralization,
especially nitrification. В© by PSP 2005.
1846 Evaluation of electrokinetic remediation of arseniccontaminated soils
Kim S.- O., Kim W.- S. and Kim K.- W. Environmental Geochemistry and Health 2005 27/5-6 (443-453)
The potential of electrokinetic (EK) remediation technology has
been successfully demonstrated for the remediation of heavy
metal-contaminated fine-grained soils through laboratory scale
and field application studies. Arsenic contamination in soil is a
serious problem affecting both site use and groundwater quality.
The EK technology was evaluated for the removal of arsenic
from two soil samples; a kaolinite soil artificially contaminated
with arsenic and an arsenic-bearing tailing-soil taken from the
Myungbong (MB) gold mine area. The effectiveness of enhancing agents was investigated using three different types of
SOILS
cathodic electrolytes; deionized water (DIW), potassium phosphate (KH2 PO4 ) and sodium hydroxide (NaOH). The results of
the experiments on the kaolinite show that the potassium phosphate was the most effective in extracting arsenic, probably due
to anion exchange of arsenic species by phosphate. On the other
hand, the sodium hydroxide seemed to be the most efficient in
removing arsenic from the tailing-soil. This result may be explained by the fact that the sodium hydroxide increased the soil
pH and accelerated ionic migration of arsenic species through
the desorption of arsenic species as well as the dissolution of
arsenic-bearing minerals. В© Springer 2005.
1847 Concentrations of potentially toxic metals in urban
soils of Seville: Relationship with different land uses
Ruiz- CortВґes E., Reinoso R., Daz- Barrientos E. and Madrid L.
Environmental Geochemistry and Health 2005 27/5-6 (465-474)
Fifty-two samples of surface soils were taken in the urban area
of Seville, to assess the possible influence of different land uses
on their metal contents and their relationship with several soil
properties. The samples corresponded to five categories or land
uses: Agricultural, parks, ornamental gardens, riverbanks, and
roadsides. Sequential extraction of metal according to the procedure proposed by the former Community Bureau of Reference
(BCR) was carried out, and pseudo-total (aqua regia soluble)
metal contents were determined. Lower organic C, total N and
available P and K contents were found in riverbank samples,
probably due to the lack of manuring of those sites, left in a
natural status. In contrast, significantly higher electrical conductivity was found in those sites, due to the tidal influence of the
nearby Atlantic Ocean. Other land uses did not show significant differences in the general properties. Concentrations of Cu,
Pb and Zn, both aqua-regia soluble and sequentially extracted,
were clearly higher in soils from ornamental gardens, whereas
the concentrations in the riverbank samples were slightly lower
than the other categories. In contrast, other metals (Cd, Cr, Fe,
Mn, Ni) were uniformly distributed throughout all land uses. A
strong statistical association is found among the concentrations
of Cu, Pb, Zn and organic C, suggesting that the larger contents
of these metals in ornamental gardens are partly due to organic
amendments added to those sites more frequently than to other
kinds of sites. Considering the conclusions of previous studies,
heavy traffic can also contribute to those вЂ�urbanвЂ™ metals in urban
soils. Periodic monitoring of the concentrations of urban metals
in busy city centres and of the quality of amendments added to
soils of recreational areas are recommended. В© Springer 2005.
1848 A kinetic analysis of solid waste composting at optimal
conditions
Komilis D.P. Waste Management 2006 26/1 (82-91)
Six municipal solid waste (MSW) and yard waste components
(food waste, mixed paper, yard waste, leaves, branches, grass
clippings) were aerobically decomposed to measure the extent
of decomposition under near optimal conditions. Decomposition was characterized by at least two principal stages, for most
components, as was indicated by the carbon dioxide production
rates. An aerobic biodegradation conceptual model is presented
here based on the principle that solids hydrolysis is the ratelimiting step during solid waste composting. The mineralizable
solid carbon of each solid waste component was assumed to
comprise the readily, the moderately and the slowly (or refractory) hydrolysable carbons, each hydrolyzing at different rates
to aqueous (water soluble) carbon. Aqueous carbon mineralizes
to CO2 at rapid rates that are not rate-limiting to the process.
Solids hydrolysis rate constants were calculated after fitting the
experimentally determined carbon dioxide production rate data to
model results. Hydrolysis rates for the readily hydrolysable carbon in all components ranged from approximately 0.06 to 0.1 d-1 ;
hydrolysis rates for the moderately hydrolysable carbon ranged
from 0.005 to 0.06 d -1 . Leaves, branches and grass clippings
did not have a readily hydrolysable carbon fraction, whilst the
leaves and branches had the largest slowly hydrolysable carbon
fractions (70%, 82%, respectively, of the total solid organic carbon). Grass and yard waste did not contain slowly hydrolysable
carbon fractions. Food waste had the largest readily hydrolysable
carbon fraction and produced the highest amount of CO2 among
all substrates. Moderately hydrolysable solid carbon fractions
353
ranged from 16% to 90% of the total solid organic carbon for all
substrates used. В© 2005 Elsevier Ltd. All rights reserved.
1849 Influence of three species of arbuscular mycorrhizal
fungi on the persistence of aromatic hydrocarbons in contaminated substrates
Volante A., Lingua G., Cesaro P. et al. Mycorrhiza 2005 16/1
(43-50)
Aromatic hydrocarbons are pollutants which have mutagenic and
carcinogenic properties as well as relatively high hydrosolubility.
Their presence in soils makes techniques such as bioremediation
an important topic for research. In this work, the effect of arbuscular mycorrhiza (AM) on the persistence of benzene, toluene,
ethylbenzene and xylene (BTEX) in artificially contaminated
substrates was evaluated. Leek plants were grown with three
AM fungal species using a specially designed mesocosm system, in which internal air and substrate samples were analyzed
by gas chromatography for BTEX content. Strong reductions in
the BTEX concentration in substrates were generally observed
in the presence of mycorrhizal plants. Residual BTEX content
ranged between nearly total disappearance (<2%) and 40% of
the original concentration, whereas there was a high persistence
of hydrocarbons in the samples of substrate alone or with nonmycorrhizal plants. These results provide first evidence for an
influence of AM activity in reducing pollution of substrates by
aromatic hydrocarbons. В© Springer-Verlag 2005.
1850 Degradation-detoxification behavior of methamidophos in phaiozem and burozem rhizosphere (Chinese)
Yu Y. and Zhou Q. Chinese Journal of Applied Ecology 2005
16/9 (1761-1764)
With plastic rhizobox system, this paper studied the degradation behavior of methamidophos in the rhizosphere and non-rhizosphere of phaiozem and burozem planted with soybean. The
results suggested that methamidophos could be rapidly decomposed in soil environment despite its higher acute toxicity, and
its residual amount in phaiozem was generally below the level in
burozem under same condition. In the absence of soybean (control), the residual amount of methamidophos at the 2nd day of
incubation was about 33% in burozem, whereas only about 26%
in phaiozem. An accelerated degradation of methamidophos in
soybean rhizospheric soil was observed, especially in phaiozem.
At the 9th day of incubation, the insecticide residue in the middle
rhizobox phaiozem and burozem with soybean was decreased by
87.5% and 76.0%, respectively, compared with that of the control.
The degradation process of methamidophos in soil environment
followed the first-order equation, and its half-life was about 2
days.
1851 A preliminary investigation into the use of ochre as a
remedial amendment in arsenic-contaminated soils
Doi M., Warren G. and Hodson M.E. Applied Geochemistry 2005
20/12 (2207-2216)
Ochre is an unwanted waste product that accumulates in wetlands
and streams draining abandoned coal and metal mines. A potential commercial use for ochre is to remediate As contaminated
soil. Arsenic contaminated soil (605 mg kg -1 ) was mixed with
different ochres (A, B and C) in a mass ratio of 1:1 and shaken
in 20 mL of deionised water. After 72 h As concentration in
solution was ca. 500 g kg-1 in the control and 1-2.5 g kg-1 in
the ochre treated experiments. In a second experiment soil:ochre
mixtures of 0.05-1:1 were shaken in 20 mL of deionised water for
24 h. For Ochres A and C, as solution concentration was reduced
to ca. 1 g kg-1 by 0.2-1:1 ochre:soil mixtures. For Ochre B,
as concentration only reached ca. 1 g kg-1 in the 1:1 ochre:soil
mix. Sorption of As was best modelled by a Freundlich isotherm
using As sorption per mass of goethite in the ochre (log K =
1.64, n = 0.79, R2 = 0.76, p 0.001). Efficiency of ochre in
removing As from solution increased with increasing total Fe,
goethite, citrate dithionite extractable Fe and surface area. В©
2005 Elsevier Ltd. All rights reserved.
354
SOILS
1852 Magnetic screening of a pollution hotspot in the Lausitz area, Eastern Germany: Correlation analysis between
magnetic proxies and heavy metal contamination in soils
Spiteri C., Kalinski V., RВЁosler W. et al. Environmental Geology
2005 49/1 (1-9)
This investigation was carried out within the scope of EU-FP5
project MAGPROX. In parallel with the work of Kalinski et al.
(2004, submitted), in which the magnetic signatures of the same
soil profiles were analysed in more detail. The вЂ�hot spotвЂ™ under
investigation was situated in the Lausitz area, Eastern Germany,
between two major power plants, Schwarze Pumpe and Boxberg.
This heavily industrialized region is known as the Black Triangle, named after the large lignite deposits and the old-technology
power plants, among other petrochemical plants, refineries, textile manufacturing and glasswork industries. The relationship
between magnetic parameters and heavy metal concentrations
(Fe, Mn, Zn, Pb, Cu, Cr, Cd, Co and Ni) in soil profiles was
determined statistically using linear regression analysis. Strong
positive correlation was observed between heavy metal concentrations as viewed preliminarily from the heavy metal and magnetic susceptibility distributions with depth (soil profiles), and
from the correlation coefficients obtained. В© Springer-Verlag
2005.
1853 Correlation between magnetic susceptibility and heavy
metals in urban topsoil: A case study from the city of Xuzhou,
China
Wang X.S. and Qin Y. Environmental Geology 2005 49/1 (10-18)
Anthropogenic influence, mainly due to urban and industrial
activities and traffic exhaust, may affect urban topsoil via atmospheric contamination and solid waste. Magnetic susceptibility
measurements were conducted on 21 urban topsoil samples from
the city of Xuzhou, China. High intensities of magnetic susceptibility were detected in the majority of the samples. SEM
analysis shows that magnetic minerals are in the form of spherules and mainly due to anthropogenic inputs. The heavy metals
Pb, Cu, Zn, Se, Sc, Mo, Fe, and Bi show strong correlations
with magnetic susceptibility, and Ag, Ba, Cd, Ni, Cr, Sb, and
Sn, on the other hand, show a weak correlation with magnetic
susceptibility. Whereas, of these metals studied, only Hg has
no significant correlation with the susceptibility. The Tomlinson
pollution load index (PLI) also shows significant correlation with
the susceptibility ( ). The present study shows that magnetic
susceptibility is a fast, inexpensive, and non-destructive method
for the detection and mapping of contaminated soils. В© SpringerVerlag 2005.
Erosion and conservation
1854 Effects of intensifying organic manuring and tillage
practices on penetration resistance and infiltration rate
Thierfelder C., AmВґezquita C E. and Stahr K. Soil and Tillage
Research 2005 82/2 (211-226)
Soil erosion, along with the contributing factors of soil crusting
and sealing, have received minimal scientific attention to date in
Latin America. This study was conducted in an Andean hillside
environment to determine how the local organic manuring and
tillage practices influence the development of soil crusting and
sealing, and the extent to which these practices influence soil
water infiltration. The aim of this study was to identify treatments that prevented superficial soil structural constraints, i.e.
treatments which maintain infiltration and therefore reduce potential soil erosion and run-off. Treatment results were measured
with a pocket penetrometer and a mini-rain simulator on nine
different cropping systems, mainly based on cassava (Manihot
esculenta Crantz), from February to November 2000 and 2001.
The cropping systems were laid out on a Ferrallic Cambisol,
an acid, vulcanically influenced soil of the Andean region. In
both cropping cycles, treatments with chicken manure application developed superficial soil crusts during the dry season. For a
treatment manured with 8 t ha-1 chicken manure, this crust meant
an increase in penetration resistance from 2.3 kg cm-2 in April
2000 to 16.2 kg cm-2 in July 2000. The change in superficial
soil structure created a notable reduction in final infiltration from
92 to 42.2 mm h -1 . A minimum tillage treatment which dis-
played the highest penetration resistance during the dry periods
of up to 46.4 kg cm-2 presented no restricting effects on soil
water intake (76.2 mm h-1 final infiltration in 2000) due to an
optimal aggregate development during 10 years of consecutive
conservation practice. Measurements of penetration resistance
and infiltration showed that soil conserving treatments, such as
minimum tillage and crop rotations, improved the physical soil
status and prevented soil crusting developing along with its negative effects on infiltration. These methods can therefore be
strongly recommended to farmers. В© 2004 Elsevier B.V. All
rights reserved.
1855 Effect of DEM resolutions in the runoff and soil loss
predictions of the WEPP watershed model
Cochrane T.A. and Flanagan D.C. Transactions of the American
Society of Agricultural Engineers 2005 48/1 (109-120)
Erosion prediction utilizing digital elevation models (DEMs) is
a logical advancement for automating the simulation process for
models such as the Water Erosion Prediction Project (WEPP).
The effects of using different DEM resolutions on watershed
simulations and the ability to accurately predict sediment yield
and runoff from different rainfall event sizes were studied using three application methods and data from six research watersheds. Simulating watersheds with a range of resolutions can
help address the problem of deciding what topographic DEM
resolution is ideal for model simulations of the watershed outlet,
the end of each hillslope, and along the slope profiles. The
three application methods studied here were: (1) Hillslope Chanleng, (2) Hillslope - Calcleng, and (3) Flowpath. The two
Hillslope methods use a representative slope profile to represent
each hillslope in the watershed, and the Flowpath method uses all
of the individual flowpaths as model input for WEPP simulations.
Results show that the Hillslope methods were not significantly
influenced by DEM resolutions; however, there was an observable interaction between resolutions and the Flowpath method.
Large rainfall events were predicted better than small events,
but fine DEM resolutions did not improve predictions of either
large or small rainfall events. Using coarse DEM resolutions for
the topographic input will not decrease the accuracy of erosion
prediction using the WEPP model and the Hillslope methods,
unless the coarseness of the DEM compromises the delineation
of the watershed or hillslopes.
1856 Controlling soil erosion and runoff with polyacrylamide and phosphogypsum on subtropical soil
Cochrane B.H.W., Reichert J.M., Eltz F.L.F. and Norton L.D.
Transactions of the American Society of Agricultural Engineers
2005 48/1 (149-154)
Sandy soil, prone to intense soil erosion, is used for agriculture in the subtropics of Brazil. This study was conducted to
determine whether soil amendments are effective for conserving
topsoil by preventing water-induced erosion on a Brazilian sandy
Alfisol soil (coarse-loamy, mixed, thermic Typic Paleudalf). A
programmable rainfall simulator was used at the experimental
station of the Federal University of Santa Maria, in a newly harvested black oat (Avena estrigosa L.) field that was moldboard
plowed and disked twice. Plots were on bare tilled soil with 8%
to 12% slopes. The soil treatments consisted of a single 5 Mg
ha-1 surface application of byproduct phosphogypsum (PG), a
single 20 kg ha-1 surface application of anionic polyacrylamide
(PAM), a combined amendment (PAM+PG) with the same rates
as above, and an unamended soil (control). Simulated rainfall
average intensity was 25 mm h-1 with a 2 h duration. Sediment and runoff samples were collected at intervals during the
experiment, and soil surface samples inside the plot were taken
after the rain for surface crusting analysis. Total soil loss was
significantly lower for the treatments than for the control and
averaged 197, 278, 217, and 2181 kg ha-1 , respectively for PG,
PAM, PAM+PG, and control treatments. PAM and PAM+PG had
steady-state runoff rates significantly less than that of the control.
All of the amendments reduced soil sediment erosion (average
90% reduction) more than final runoff (average 35% reduction).
Using amendments to reduce precipitation-induced erosion is a
possible alternative conservation practice in this region of the
world. В© 2005 American Society of Agricultural Engineers.
SOILS
1857 Basal sediment concentration measurement using a
time domain reflectometry method
Starr G.C. Transactions of the American Society of Agricultural
Engineers 2005 48/1 (205-209)
Sediment concentration measurement in high-concentration runoff waters is highly problematic. A novel device was developed for high-concentration measurements. This device was
then used to measure sediment concentrations during monsoon
runoff events at the USDA-ARS Walnut Gulch experimental watershed in southeast Arizona as an example application. Data
were obtained using a 55 cm, three-prong, embedded time domain reflectometry probe and sediments in a range of size classes
from the site under laboratory conditions. In the laboratory, the
sensorвЂ™s concentration output was calculated using a model and
the empirical function describing pure water. Without sedimentspecific calibration, laboratory validation indicated agreement
with known concentrations within about 0.02 kg L-1 for sediment
and water mixtures and within 0.2 kg L-1 when the probe was
completely buried in 0 to 2.5 cm channel bed material. In the
field application, the probe was installed in the base and center of
a flume. Basal (0 to 2 cm depth) sediment concentrations were
monitored during three flows with peak discharges of 5, 70, and
130 m 3 s-1 , representing small, intermediate, and large events.
For the large and intermediate events, basal sediment concentrations rose from 0.4 to 1.2 kg L-1 to a plateau of 1.5 to 1.9 kg
L-1 after the flow peak. The plateau extended through much of
the tail of the hydrograph before falling to back to 0.4 to 1.2 kg
L-1 . The small event had a similar progression but lower overall
concentrations of 0.2 to 0.8 kg L -1 . These observations are
consistent with a period of high sediment transport and channel
erosion in the tail of monsoon runoff hydrographs. The dielectric method provides in-situ measurements in high-concentration
environments where traditional methods fail.
1858 The role of impoundments in the sediment budget of
the conterminous United States
Renwick W.H., Smith S.V., Bartley J.D. and Buddemeier R.W.
Geomorphology 2005 71/1-2 (99-111)
Previous work on sediment budgets for U.S. agricultural regions
has concluded that most sediment derived from accelerated erosion is still on the landscape, primarily in colluvial and alluvial
deposits. Here we examine the role of small impoundments in the
subcontinental sediment budget. A recent inventory based on a
30-m satellite imagery reveals approximately 2.6 million ponds,
while extrapolation from a sample of 1:24,000 topographic quadrangles suggests the total may be as large as 8-9 million. These
ponds capture an estimated 21% of the total drainage area of
the conterminous U.S., representing 25% of total sheet and rill
erosion. We estimate the total sedimentation in these small impoundments using three different methods; these estimates range
from 0.43 to 1.78 109 m3 yr-1 . Total sedimentation in 43,000
reservoirs from the National Inventory of Dams is estimated at
1.67
109 m3 yr-1 . Total USLE erosion in 1992 was 2.4
109 m3 yr-1 , and export to coastal areas is estimated at 0.6
109 m3 yr-1 . Total sedimentation in impoundments is large in
relation to upland erosion, in apparent contradiction to previous
studies that have identified colluvial and alluvial deposition as
the primary sinks. Several alternative hypotheses that could help
explain this result are proposed. Regardless of which of these
alternatives may prove to be the most significant in any given
setting, it is clear that most sedimentation is now taking place
in subaqueous rather than subaerial environments, and that small
impoundments are a major sediment sink. В© 2005 Elsevier B.V.
All rights reserved.
1859 The implications of changes in population, land use,
and land management for surface runoff in the Upper Nile
Basin Area of Ethiopia
Hurni H., Tato K. and Zeleke G. Mountain Research and Development 2005 25/2 (147-154)
Much concern has been raised about population increase in the
highlands of Ethiopia and its potential to decrease runoff from the
upper Nile Basin to the lowland countries of Sudan and Egypt.
The present article examines long-term data on population, land
use, land management, rainfall, and surface runoff rates from
small test plots (30 m2 ) and micro-catchments (73-673 ha) in
the highlands of Ethiopia and Eritrea, Although the data were
355
generated only on small areas, the results of the analyses can
nevertheless be used to draw some conclusions relevant to the
highland-lowland water controversies that have persisted in this
particular region for many decades. The data indicate that there
have been no significant trends over the long term in total annual
rainfall in the highlands over the past 30-50 years. Nevertheless,
test plot surface runoff rates are clearly influenced by land use and
soil degradation, and hence by population density and duration
of agriculture. In effect there is 5-30 times more surface runoff
from cultivated or degraded test plots than from forested test
plots. Analysis and interpretation of data support the hypothesis
that surface runoff and sediment yield from the Ethiopian and
Eritrean highlands into the upper Nile Basin have most probably increased in the long term due to intensified land use and
land degradation induced by population increase, when seen in
a historical perspective. Rates of base flow, in turn, must have
decreased during the same period, but to a much lesser extent,
although conclusive empirical evidence cannot be gained from
this experimental setting. One can assume that soil and water
conservation measures aiming to ensure long-term livelihoods in
the humid to sub-humid highlands will, on the one hand, barely
affect overall catchment runoff to the downstream areas, though
they will considerably reduce surface runoff and soil loss on
slopes as well as river sedimentation rates. On the other hand, in
a semiarid catchment where intensive soil and water conservation
was carried out, reduction in runoff rates was more pronounced.
It can be concluded that population increase in the Ethiopian
highlands increased overall runoff rates to lowland areas in earlier
times, while recent efforts to conserve watersheds might affect
total runoff rates in catchments only in semiarid parts, and much
less in humid parts of the Ethiopian highlands.
1860 Surface erosion assessment in two Calabrian basins
(southern Italy)
Antronico L., Coscarelli R. and Terranova O. IAHS-AISH Publication 2005 -/299 (16-22)
The present study presents an assessment of the erosion for two
basins located on the Ionian side of southern Calabria (southern
Italy). Two different approaches are considered to evaluate soil
erosion: a qualitative method, based on aerial photo interpretative
analysis, and a quantitative method, based on the RUSLE model.
The percentage of area affected overall by surface erosion proves
to be greater using the quantitative approach (38.5%) compared
to the qualitative (13.3%). The mean erosion estimated using
RUSLE is about 3.5 mm year-1 and can be compared with the
values for Calabria reported in the literature. The application of
the two approaches has shown that the spatial-temporal distribution of the parameters influencing the erosive process plays a
relevant role.
1861 Gully erosion: Impacts, factors and control
Valentin C., Poesen J. and Li Y. Catena 2005 63/2-3 (132-153)
Gully erosion attracts increasing attention from scientists as reflected by two recent international meetings [Poesen and Valentin
(Eds.), Catena 50 (2-4), 87-564; Li et al., 2004. Gully Erosion Under Global Change. Sichuan Science Technology Press,
Chengu, China, 354 pp.]. This growing interest is associated
with the increasing concern over off-site impacts caused by soil
erosion at larger spatial scales than the cultivated plots. The
objective of this paper is to review recent studies on impacts,
factors and control of gully erosion and update the review on
вЂ�gully erosion and environmental change: importance and research needsвЂ™ [Poesen et al., 2003. Catena 50 (2-4), 91-134.].
For the farmers, the development of gullies leads to a loss of crop
yields and available land as well as an increase of workload (i.e.
labour necessary to cultivate the land). Gullies can also change
the mosaic patterns between fallow and cultivated fields, enhancing hillslope erosion in a feedback loop. In addition, gullies tend
to enhance drainage and accelerate aridification processes in the
semi-arid zones. Fingerprinting the origin of sediments within
catchments to determine the relative contributions of potential
sediment sources has become essential to identify sources of potential pollution and to develop management strategies to combat
soil erosion. In this respect, tracers such as carbon, nitrogen, the
nuclear bomb-derived radionuclide 137 Cs, magnetics and the
strontium isotopic ratio are increasingly used to fingerprint sediment. Recent studies conducted in Australia, China, Ethiopia
356
SOILS
and USA showed that the major part of the sediment in reservoirs
might have come from gully erosion. Gullies not only occur in
marly badlands and mountainous or hilly regions but also more
globally in soils subjected to soil crusting such as loess (European
belt, Chinese Loess Plateau, North America) and sandy soils (Sahelian zone, north-east Thailand) or in soils prone to piping and
tunnelling such as dispersive soils. Most of the time, the gullying
processes are triggered by inappropriate cultivation and irrigation systems, overgrazing, log haulage tracks, road building and
urbanization. As exemplified by recent examples from all over
the world, land use change is expected to have a greater impact
on gully erosion than climate change. Yet, reconstructions of
historical causes of gully erosion, using high-resolution stratigraphy, archaeological dating of pottery and 14 C dating of wood
and charcoal, show that the main gully erosion periods identified
in Europe correspond to a combination not only of deforestation
and overuse of the land but also to periods with high frequency
of extreme rainfall events. Many techniques have proved to be
effective for gully prevention and control, including vegetation
cover, zero or reduced tillage, stone bunds, exclosures, terracing
and check dams. However, these techniques are rarely adopted
by farmers in the long run and at a larger spatial scale because
their introduction is rarely associated with a rapid benefit for the
farmers in terms of an increase in land or labour productivity and
is often contingent upon incentives. В© 2005 Elsevier B.V. All
rights reserved.
1862 Monitoring of gully erosion on the Loess Plateau of
China using a global positioning system
Wu Y. and Cheng H. Catena 2005 63/2-3 (154-166)
With the development of a technique, global positioning system
(GPS) has become progressively less expensive, lighter and easier
to use. The accuracy of GPS has been improved and it appears
applicable to the continuously monitoring morphology changes
on the earth surface with small and slow change. The objective
of this study is to use GPS to measure the morphology of gullies
in a small catchment near Suide, Shaanxi Province, China. There
are three main gully types in the study area: bank gullies, floor
gullies, and hill slope gullies, and this study mainly focuses on
the hill slope gullies. The hill slope gullies in the study area
are mainly discontinuous and are developing rapidly. The gully
density in the study area is very large. The retreat rate of hill
slope gullies is 0.16-2.02 m year-1 . The relationships between
the upslope drainage area (A) and the critical slope gradient (S)
for hill slope gullies is S = 0.1839A-0.2385 . The values of AS2
range from 41 to 814 m2 for the hill slope gully headcuts, and
most of them fell into the range of 100-300 m2 . Both of these
relationships are suggested as indexes for estimating the location
of gully headcuts. В© 2005 Elsevier B.V. All rights reserved.
1863 Spatial and temporal assessment of linear erosion in
catchments under sloping lands of northern Laos
Chaplot V., Coadou Le Brozec E., Silvera N. and Valentin C.
Catena 2005 63/2-3 (167-184)
Linear erosion (LE), including rilling and gullying, has been
identified as the major problem for sustainable agriculture in
steepland areas. It causes severe environmental, economic, and
social impacts. This issue is even more crucial in those areas
undergoing rapid changes in land use, as for example northern
Laos, and may dramatically affect soil conservation. Despite an
increasing interest in the sloping lands of tropical areas, field
evaluations of LE are still infrequent. Furthermore, the controlling environmental factors of topography, land use, climate
and soils at the catchment level are seldom analysed. Our main
objective was to quantify the spatial and temporal variations of
LE at the catchment level and at a yearly basis. The study was
conducted in a 0.62 km2 watershed of Laos (Luang Prabang
province) representative of the slash and burn systems of sloping
lands. Linear erosion was monitored from 2001 to 2003 within
9 sub-catchments of differing surface areas, topographic characteristics and land use. The length, depth and width of the linear
erosion features were recorded every 5-m from their headcuts to
their outlets in order to estimate the total catchment LE. 52 linear
features, mainly rills, were formed or developed within the study
area with a mean erosion rate of 1.3 Mg ha-1 y-1 . LE rates ranged
between 0.1 Mg ha-1 y-1 in 2003 to 2.4 Mg ha-1 y -1 in 2001. LE
features mostly occurred within croplands where erosion rates
reached 18 Mg ha-1 y-1 . In 2001 and 2002 there was a significant
correlation between LE and the proportion of the catchment area
under crops (r = 0.88 and r = 0.69, respectively). However this
was not the case in 2003 when few rills developed. In 2002 only,
LE correlated well with the catchment surface area, the mean
slope gradient and the sub-catchment perimeter confirming the
non-constancy of LE landscape relation under varying rainstorm
conditions. A linear regression model for LE prediction at the
catchment level, generated from 2001 data, was able to explain
78% of LE variance for the 9 sub-catchments. However, this
model was unable to predict accurately LE for 2002 and 2003
(ME > 5 Mg ha-1 y-1 ). This method for quantifying the linear
erosion at the catchment level and some of its controlling factors
can also be used for prediction over larger areas since topography and land use data, closely correlated with LE, are easily
accessible. В© 2005 Elsevier B.V. All rights reserved.
1864 Gully incision as a key factor in desertification in an
arid environment, the Negev highlands, Israel
Avni Y. Catena 2005 63/2-3 (185-220)
Gully incision has been eroding the alluvial sediments and loess soils deposited and developed along the valleys in the arid
and semiarid regions of Israel. This phenomenon is critical in
the arid regions of the Negev Highlands where the agricultural
fields, the main floral biomass and the areas which have the
highest grazing value, are limited to narrow valleys filled with
redeposited loessial sediments. The headcut migration and gully
development in the region were studied between 1990 and 2001
in three representative drainage basins (Zipporim, Revivim and
Sekher). During flood events, the runoff penetrates the alluvial
cover of the valleys, forming vertical headcuts, which gradually
retreat up the valley. The runoff is channeled into narrow gullies, preventing the floodwater from spreading over the whole
width of the valley. The change in irrigation efficiency along
the valleys is reflected in a sharp estimated drop of 70-90% in
the floral biomass, causing the reduction of the range value by
83-99%. During the monitoring time interval (1990-2001), the
linear gully retreat in the study area ranged between 12.3 and
250 m an average rate of 1.12-22.7 m year-1 for each gully head.
The process is accompanied by erosion of soil, which has high
agricultural and range value. The total soil losses in these sites
ranged between 800 and 9000 m3 at an average rate of 81-818
m3 year-1 for each gully head, which is equivalent to 121-1227
Mg year-1 . During the monitoring period, approximately 0.110.87 ha of land lost its agricultural and range value in each basin
under study, at an average rate of 0.01-0.079 ha year-1 . Since
the Byzantine period (1400 BP), approximately 6.5 ha, which is
10% of the land that had high agricultural and range value in the
Zipporim valley, lost its value due to gully erosion. No recovery
effects of the gully channels were found in the nearby region.
The soil erosion is generated by a long-term natural dynamic
change in the soil / rock ratio evolving within the drainage basins
through time since the termination of the last glacial phase. The
loessic sediments, originally deposited within the drainage basins
during the late Pleistocene glacial stage, are being removed under the present Holocene climate in several erosion stages. This
ongoing phenomenon is causing degradation of soil and biomass
and is severely reducing the agricultural and range potential of
the region. These parameters indicate that an ongoing process
of desertification is active in the arid environment of the Negev
Highlands, and is advancing in proportion to the headcut retreat
rates in the region. The soil erosion and headcut retreat have been
active in the Negev Highlands for the last few millennia. If these
processes continue in the future, the Negev Highlands region will
lose its agricultural potential within a few millennia. However,
the fact that the ancient inhabitants of the region implemented
successful long-term land conservation techniques already 3000
years ago, implies that a sustainable land management policy can
be adapted to the Negev Highlands, as well as to other semi-arid
regions in the Middle East. В© 2005 Elsevier B.V. All rights
reserved.
1865 Rapid development and infilling of a buried gully under
cropland, central Belgium
Vanwalleghem T., Bork H.R., Poesen J. et al. Catena 2005 63/2-3
(221-243)
Analysis of contemporary and past gully erosion and infilling
SOILS
processes allowed to reconstruct the long-term evolution of a
permanent gully system under cropland. An active and a buried
gully under cropland were investigated. The recent sediment
deposits within the active gully, adjacent to the buried gully,
showed that the recent gully was filling in at a mean rate of
6.4 cm a -1 . In the buried gully, several erosion and deposition
phases could be identified and the type of deposited sediments
revealed a complex infilling history. Charcoal, pottery and brick
fragments of different sizes were found at all depths of the gully
infilling. Their age indicates that the first gully incised after the
midst of the 17th century, most probably in the second half of the
18th century or the early 19th century. Gully morphology and
analogy with the processes in the recent gully indicate that the
buried gully filled in rapidly. Overall, five cycles of cut and fill
occurred in 350 years or less and four cycles even within little
less than a few decades, indicating that gully development and
infilling under cropland can be very rapid processes. В© 2005
Elsevier B.V. All rights reserved.
1866 History, origin and extent of soil erosion on Easter
Island (Rapa Nui)
Mieth A. and Bork H.- R. Catena 2005 63/2-3 (244-260)
The isolated Easter Island (Rapa Nui) is an outstanding example
of land degradation caused by land use in a sensitive ecosystem.
The focus of the investigation was placed on Poike peninsula,
the most eastern part of Rapa Nui. While Poike peninsula was
once supplied with fertile soils, in large areas desertification takes
place today. Detailed analysis of soil profiles allowed the reconstruction of the history and of causes and effects of soil erosion
and gullying in the context of land use history and cultural evolution. The results of the stratigraphic analysis prove that from
the beginning of human settlement around AD 300/600 until AD
1280 the agriculture on Poike peninsula was characterised by
sustainable land use and a traditional type of agro-forestry. Soil
erosion was not significant. At around AD 1280 the woodland on
Poike, dominated by the endemic palm Jubaea sp., was cleared
by slashing and burning. Intensive farming on the upper slopes
of the volcanic peninsula resulted in sheet erosion lasting until
the 20th century. Settlements and ceremonial places which were
built around AD 1300 on downslope areas were buried soon by
sediments. Agriculture ceased around AD 1400 on downslope
areas as the fertile soils were completely eroded. From AD 1400
until the late 19th century sheet erosion and the accumulation of
fine-layered sediments migrated upslope. On average 8.6 Mg of
soil per hectare and per year were reworked by erosion (eroded
and accumulated within the catchment). Gullying began on Rapa
Nui with the sudden increase in the number of sheep during the
early 20th century. Gullies are still developing on the island and
their ongoing enlargement created extended badlands on Poike
which pose a significant problem for ecological and archaeological conservation strategies. Gullying rates exceed 190 Mg ha -1
y-1 . В© 2005 Elsevier B.V. All rights reserved.
1867 Runoff and erosion in the Black Marls of the French
Alps: Observations and measurements at the plot scale
Mathys N., Klotz S., Esteves M. et al. Catena 2005 63/2-3
(261-281)
The experimental basins of Draix in the southern French Alps
have been monitored since 1984 in order to quantify and analyse
the incidence and patterns of erosion in the badlands developed
on Black Marl formations. In order to analyse the rainfall-runoff behaviour of the mudstone slopes, rainfall simulations were
conducted on small plots 1 m2 in area. Four different local
geomorphologic conditions were selected for the experiments:
(a) steep slope parallel or (b) perpendicular to the bedding, (c)
moderate slope and (d) gravel-covered surface, both parallel to
the bedding. Rainfall simulations were performed at a moderate intensity (12-25 mm h-1 ) for 30 min on three plots in each
location. Different delays between simulations offered different
initial soil wetnesses. A simulation during high-intensity rainfall
(90-150 mm h-1 ) for 30 min was made on one plot of each type.
One plot of each type was selected for monitoring during the following summer and autumn. In dry conditions, runoff was low
or negligible. A second simulation carried out 1 day later again
produced very low runoff coefficients. Runoff increased slightly
when the interval between rainfall simulations was reduced to
30 min. In this case, a few grams of sediment were eroded,
357
whereas no erosion was observed in the first two cases. Under
high-intensity conditions, runoff began quickly and the runoff
coefficients were high (20-50%). Erosion was notable, but not
significantly different from dry conditions. The behaviour was
very different during natural rainfall events, in particular summer
storms: even if the mean rainfall intensity was lower than 60 mm
h-1 in 30 min, short periods of high intensity (more than 100 mm
h-1 in 5 min) revealed substantial erosion activity: more than
700 g m-2 on all the plots for a rainfall event of 54 mm in 3 h and
more than 600 g m -2 for an event producing 26 mm. However,
the runoff coefficients were on the same order as those of the last
experiment under high-intensity conditions (32-55%). The rainfall intensity over the short duration and the kinetic energy of the
raindrops were the main factors influencing particle detachment
and movement.
1868 Stochastic components in the gully erosion modelling
Sidorchuk A. Catena 2005 63/2-3 (299-317)
The great complexity of the geo-mechanical, structural, and electro-chemical forces in soil, as well as of initial and boundary conditions in the equations of hydrodynamics, leads to a necessity
of spatial/temporal averaging of deterministic equations related
to soil behaviour. The stochastic terms, which appear in the
equations after averaging procedures, must be incorporated into
the modelling of erosion features. In this study, a new method of
estimating detachment rate was used in stochastic gully erosion
modelling. It is based on estimation of the probability of excess
of driving forces above resistance forces in the interaction of
water flow and structured soil. Knowledge of the probability
density functions for the flow and soil main characteristics (as
flow velocity, soil cohesion, aggregate size and others) makes
it possible to calculate theoretically the rate of cohesive soil
erosion for any combination of these stochastic variables. The
proposed theory allows explicit explanation of relationships between detachment rate and flow/soil characteristics. Detachment
rate increases with flow velocity more rapidly for soil with higher
cohesion and larger aggregates. This theory also shows great difference in type of soil erosion for relatively high and relatively
low flow velocities, and explains rather high errors in calculating
of soil erosion rate even with detailed models. В© 2005 Elsevier
B.V. All rights rserved.
1869 Dynamic modelling for linear erosion initiation and development under climate and land-use changes in northern
Laos
Chaplot V., Giboire G., Marchand P. and Valentin C. Catena
2005 63/2-3 (318-328)
Linear erosion (LE) induced either by piping or overland flow is
one of the most active factors in the evolution of soils. During
single storm events LE may remove enormous amounts of soil
material from the uplands to the bottomlands and has thus become a broad challenge for food supply, food security, and human
health. Recent and rapid changes in land-use and climate patterns
in the sloping lands of tropical areas may dramatically increase
LE. Our main objective was to investigate to what extent one
could use direct flow velocity estimations from dynamic models
for predicting LE initiation and development at the event level.
The second objective was to estimate the impact of expected landuse and climate changes on LE. The study was conducted in the
0.62 km 2 watershed of northern Laos presented inChaplot et al.
(2005). Field observations of the formation and the development
of LE features throughout 2001 were compared to flow velocity
estimations from an existing surface water routing algorithm developed at Utrecht University ([De Roo, A.P.J., Wesseling, C.G.
and Ritsema, C.J. 1996. LISEM: a single event physically based
hydrologic and soil erosion model for drainage basins. I: theory,
input and output. hydrological processes 10 (8): 1107-1117.]).
In 2001, two main rainfall events were responsible for the formation or development of 14 linear features with a total length
of 972 m and an erosion rate of 3.5 Mg ha-1 . The water routing algorithm was calibrated using the water and the sediment
hydrographs observed at the watershed outlet during the first
rainfall event. Assuming realistic estimations of flow velocity in
hillslopes, a threshold of 0.062 m s-1 for linear erosion estimated
over 10-m cells was defined. This threshold, validated using the
remaining rainfall event, accurately predicted the length (mean
error of estimate of less than 15%) and location of LE features.
358
SOILS
Using this simulation tool, an increase of the percentage of land
under cultivation from 9% to 100% resulted in 600% increase
in linear erosion. The tested scenarios of climate changes had
less impact on linear erosion. В© 2005 Elsevier B.V. All rights
reserved.
1870 Soil erosion and sediment deposition in the Belgian loess belt during the Holocene: Establishing a sediment budget
for a small agricultural catchment
Rommens T., Verstraeten G., Poesen J. et al. Holocene 2005
15/7 (1032-1043)
A method to establish a Holocene sediment budget for a 103
ha agricultural catchment representative for the Belgian loess
belt is presented. Soil erosion and sediment deposition were
determined based on 185 coring locations and a large excavation in the valley bottom. Results were integrated in a GIS
and interpolation techniques applied to derive spatial patterns of
erosion and sedimentation. Total soil erosion, sediment deposition and sediment export were calculated and the results show
that volumes are highly dependent on the interpolation technique
used. Sediment delivery ratios between 20% and 42% are derived and are consistent with data reported in previous studies.
This clearly shows that the majority of the sediments produced
during the Holocene have been stored near their source area and
have not been delivered to the downstream rivers. The spatial
distribution of soil erosion and sediment deposition within the
catchment is strongly dependent on slope gradient and position
within the catchment, which suggests that, since human impact
began, topography has been the main factor determining longterm soil erosion and sedimentation. В© 2005 Edward Arnold
(Publishers) Ltd.
1871 Kinematics of flow within headcut scour holes on
hillslopes
Bennett S.J. and Alonso C.V. Water Resources Research 2005
41/9 (1-12)
[1] The development and migration of headcuts in rills and gullies
can adversely impact soil resources in agricultural areas and accelerate landscape degradation worldwide. Analytical treatments
of this erosion process have been based on a turbulent impinging
jet analogue, though partially validated by field and laboratory
data. Experiments were conducted using fixed headcut models to
define the mean flow structure within these erosional features and
to assess the applicability of similarity arguments for jets to characterize this flow domain. These data show that (1) flow within
headcut scour holes is analogous to plane turbulent reattached
wall jets and (2) similarity arguments used to define the limits,
length scales, and velocity distributions in classical free jets and
wall jets are applicable within discrete regions of the headcut
scour hole domain but are affected by the ventilation characteristics of the overfall. This study contributes new knowledge on
the hydrodynamics within headcut scour holes, and it confirms
the applicability of jet theory for analyzing such soil erosion
processes. Copyright 2005 by the American Geophysical Union.
1872 An adaptive management process for forest soil
conservation
Curran M.P., Maynard D.G., Heninger R.L. et al. Forestry
Chronicle 2005 81/5 (717-722)
Soil disturbance guidelines should be based on comparable disturbance categories adapted to specific local soil conditions, validated by monitoring and research. Guidelines, standards, and
practices should be continually improved based on an adaptive
management process, which is presented in this paper. Core components of this process include: reliable monitoring protocols for
assessing and comparing soil disturbance for operations, certification and sustainability protocols; effective methods to predict
the vulnerability of specific soils to disturbance and related mitigative measures; and, quantitative research to build a database
that documents the practical consequences of soil disturbance for
tree growth and soil functions.
1873 Enhanced dust deposition by trees recently established
on degraded rangeland
McGowan H. and Ledgard N. Journal of the Royal Society of
New Zealand 2005 35/3 (269-277)
Results from 2 years of dust deposition monitoring in a 10-yearold Pinus nigra plantation near Lake Tekapo are presented. They
show that recently established plantations significantly enhance
dust deposition rates. This could reverse a cycle of soil loss and
enhance vertical accretion of soil, which would provide more
options for future land use. However, observations indicate that
even under such enhanced conditions for soil formation, it would
take several thousand years to replace the soil lost to erosion since
European farming practices were first introduced to the northern
section of the Mackenzie Basin.
1874 Response of sediment production to land-use change
in Luergou watershed of Loess Plateau (Chinese)
Zhang Z., Wang S., Sun G. et al. Chinese Journal of Applied
Ecology 2005 16/9 (1607-1612)
The study on the effects of different land use patterns on the sediment production in Luergou watershed of Loess Plateau indicated
that in comparing with 1982, the areas of forest and grass and of
terrace in 1989 increased by 5% and 2.09%, respectively, while
that of slope plowland decreased by 1.5%, with the area of naked
land and shrubbery respectively increased and decreased a little.
During 1998-2000, with the increase of vegetation cover and
the decrease of steep slope plowland, the sediment production
reduced significantly under high precipitation, 85 326 and 52
937 t under the precipitation of 803 and 786 mm, respectively,
and not distinguishable in dry years. The reduction effect had
a strong seasonality, which consisted with rainfall distribution.
For example, in a month with 50 mm precipitation, the mean
daily sediment concentration was reduced by 6 kg m-3 , while in
a month with 100 mm precipitation, the reduction was 12 kg m-3 .
Rainfall intensity also played an important role in soil erosion
and sediment production, regardless of land use conditions.
1875 Effects of forest vegetation on runoff and sediment
production on sloping lands of Loess area (Chinese)
Zhang X., Yu X., Wu S. et al. Chinese Journal of Applied Ecology
2005 16/9 (1613-1617)
Based on the 1985-2003 fixed-position data in 9 runoff plots of
Caijiachuan watershed in the Jixian county of Shanxi Province in
loess area, this paper discussed the relationships between vegetation and runoff and sediment production on sloping lands of loess
area. The results showed that natural-secondary forest had better
function in soil and water conservation than artifical Robinia
pseudoacacia forest, with runoff and sediment produced 65%82% and 23%-92%, respectively. Multiple regression analysis
indicated that runoff and sediment production had a significant
correlation with rainfall and its intensity, but this relationship was
decreased gradually with increasing canopy density. Different
land-use type had different runoff and sediment production, e. g.,
Ostryopsis davidiana and natural-secondary forests had the least
runoff and sediment production, artificial Robinia pseudoacacia
and Pinus tabulaeformis forests had 5 folds of it as much as
Ostryopsis davidiana forest, mixed apple trees and crops had
17.14 and 3.96 folds of it than Ostryopsis davidiana forest, respectively, while high-standard soil preparation could decrease
the production obviously. Gray correlation analysis suggested
that the stand canopy density and the biomass of herb and litter
were the most important factors affecting the runoff and sediment
production on sloping land, whose gray correlation degrees all
exceeded 0.6. Mixed forest with multi-layer stand structure and
shrub forest should be developed in vegetation re-construction
of loess area, which could help to increase the coverage and
litter thickness to dramatically decrease the runoff and sediment
production on sloping land.
1876 Mechanism of watershed soil erosion control by vegetation (Chinese)
Qin F., Yu X., Zhang M. and Xie Y. Chinese Journal of Applied
Ecology 2005 16/9 (1618-1622)
From the view of hydrodynamics, this paper studied the acting
mechanism of tree, grass and forest litter on slope runoff velocity
and kinetic energy. The results showed that slope runoff head loss
was related to slope gradient, forest density, net rainfall intensity
and slope length. The relationship of water head loss with the
distance among trees and the diameter at the ground of tree was E
/ (D/b)4/3 . The grass on slope turned to be curved with s flowing,
and thus, increased the bottom resistance of flow, and reduced the
HYDROLOGY
shearing stress of soil surface. Therefore, silt-carrying capacity
decreased dramatically. The analysis of actually measured materials of each rainfall, runoff and sediment, and the comparison
of Qiaozi eastern gully and Qiaozi west gully in Tianshui city of
Gansu Province showed that under same precipitation condition,
the runoff, sediment yield, flood peak discharge and maximum
sediment transport rate in treated watershed was less than those
in untreated watershed, suggesting that vegetation was obviously
beneficial to water reservation and water and soil conservation.
1877 Soil properties and water holding capacities of Michelia macclurei, Schima superba and Castanopsis fissa stands
(Chinese)
Xue L., Li Y., Qu M. et al. Chinese Journal of Applied Ecology
2005 16/9 (1623-1627)
The study showed that the soil density, total porosity, natural
water capacity and capillary moisture capacity were 1.19 g cm-3 ,
56.73%, 15.7% and 43.2% in Michelia macclurei stand, 1.26
g cm-3 , 54.18%, 13.0% and 37.8% in Schima superb stand, and
1.06 g cm-3 , 60.74%, 19.4%, and 45.8% in Castanopsis fissa
stand, respectively. Soil water holding capacity and aeration
were good in Castanopsis fissa stand but bad in Schima superba
stand, whereas Michelia macclurei stand had a medium water
holding capacity and a bad aeration. The water holding capacity
of litter per tree was in order of Michelia macclurei (20 kg)
> Castanopsis fissa (15 kg) > Schima superba (8 kg), whereas
that of litter in stand was Castanopsis fissa (17 t hm-2 ) > Michelia macclurei (16 t hm-2 ) > Schima suPerba (13 t hm-2 ). The
nutrient storage of litter per tree was 112.71, 31.20 and 87.30 g
in Michelia macclurei, Schima superba and Castanopsis fissa
stands, respectively, and that of litter in stand was 84.35, 51.86
and 98.11 kg hm-2 , respectively. The soil in the three stands was
strong acidic, and the content of soil organic matter, total N, total
P, total K, alkalized N, available P and available K was 18.43 g.
kg-1 , 0.69 g kg-1 , 0.17 g kg-1 , 5.83 g kg-1 , 45.67 mg kg-1 , 0.83
mg kg-1 and 23.13 mg kg-1 in Michelia macclurei stand, 13.40
g kg-1 , 0.68 g kg-1 , 0.20 g kg-1 , 12.32 g kg-1 , 40.78 mg kg-1 , 0.85
mg kg-1 and 90.63 mg kg-1 in Schima superba stand, and 28.50
g kg-1 , 0.97 g kg-1 , 0.23 g kg-1 , 18.77 g kg-1 , 73.40 mg kg-1 , 1.45
mg kg-1 and 66.50 mg kg-1 in Castanopsis fissa stand, respectively. Soil bacteria accounted for > 94% of soil microbes, and
their individuals were 41 105, 34 104 and 5.3 104 g-1 in Michelia
macclurei, Schima superba and Castanopsis fissa stands, respectively. The activities of soil urease, catalase and phosphatase in
Castanopsis fissa stand were the greatest among the three stands,
while soil cellulase activity in Michelia macclurei stand was
greater than that in other two stands. In a word, soil fertility of
Castanopsis fissa stand was the highest among three test stands.
1878 Landscape pattern and its functioning after ecological reconstruction in black soil region of northeast China
(Chinese)
Wei J. and Xiao D. Chinese Journal of Applied Ecology 2005
16/9 (1699-1705)
Taken Baiquan County in Heilongjiang Province as a case, this
paper studied the effects of regional ecological reconstruction on
agricultural landscape pattern and its functioning in soil and water
conservation, with the spatial expression and quantity identification investigated based on Geographic Information System (GIS)
and field data. The landscape pattern index in class scale, transition matrix of landscape elements, macrostructure of shelterbelt
networks, and spatial distribution and hydrological characteristic
of reservoirs and ponds in 1989 and 2002, as well as the effects
of landscape pattern and its spatial configuration change on soil
and water loss were compared. The results showed that artificial
ecological reconstruction changed the quantity and spatial configuration of landscape patterns in regional scale, and exerted a
significant effect on soil and water conservation. From 1989 to
2002, farmland area reduced 24 731.01 hm2 , while forest land,
grassland and water area increased 11 728.56, 1 838.97 and 1
190.97 hm2 , respectively. The controlled eroded land increased
by 55%, and the shelterbelt-protected farmland increased by
82.2%. The number and storage capacity of reservoirs and ponds
added up to 1 490 and 2.4 108 m3 , respectively, and 43.7% of
intercepted surface runoff of whole landscape was collected.
359
1879 Soft-ridged bench terrace design in hilly loess region
(Chinese)
Cao S., Chen L. and Gao W. Chinese Journal of Applied Ecology
2005 16/8 (1443-1449)
Reconfiguration of hillside field into terrace is regarded as one of
the key techniques for water and soil conservation in mountainous
regions. On slopes exceeding 30В°, the traditional techniques of
terracing are difficult to apply as risers(i. e., backslopes), and if
not reinforced, are so abrupt and easy to collapse under gravity
alone, thus damaging the terrace. To improve the reconfiguration
of hillside field into terrace, holistic techniques of soft-ridged
bench terrace engineering, including revegetation with trees and
planting grasses on riser slopes, were tested between 1997 and
2001 in Xiabiangou watershed of YanвЂ™an, Shaanxi Province. A
"working with Nature" engineering approach, riser slopes of 45В°,
similar to the pre-existing slope of 35В°, was employed to radically
reduce gravity-erosion. Based on the concepts of biodiversity
and the principles of landscape ecology, terrace benches, bunds,
and risers were planted with trees, shrubs, forage grasses, and
crops, serving to generate a diverse array of plants, a semiforested area, and to stabilize terrace bunds. Soft-ridged bench
terrace made it possible to significantly reduce hazards arising
from gravity erosion, and reduce the costs of individual bench
construction and maintenance by 24.9% and 55.5% of the costs
under traditional techniques, respectively. Such a construction
allowed an enrichment and concentration of nutrients in the soils
of terrace bunds, providing an ideal environment for a range of
plants to grow and develop. The terrace riser could be planted
with drought-resistant plants ranging from forage grasses to trees,
and this riser vegetation would turn the exposed bunds and risers
existing under traditional techniques into plant-covered belts,
great green ribbons decorating farmland and contributing to the
enhancement of the landscape biology.
1880 A preliminary study on vegetation-erosion dynamics
and its applications
Wang Z., Wang G., Li C. and Wang F. Science in China, Series
D: Earth Sciences 2005 48/5 (689-700)
Vegetation-erosion dynamics is a new interdisciplinary science,
studying the laws of evolution of watershed vegetation under the
action of various ecological stresses. Introducing a qualitative
expression of ecological stresses in this paper, the present authors
establish the coupled differential equations for the vegetationerosion process and derive a theoretical solution. The model
is applied to the Anjiagou watershed on the Loess Pateau and
the Xiaojiang watershed and its sub-watersheds on the Yunnan
Plateau. The calculated results agree well with the vegetation
development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with
which we can predict the development trend of vegetation under
no human stresses. It is demonstrated that the erosion control
is important for vegetation development and reforestation must
be a long-term strategy. On the Yunnan Plateau with relatively
high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau
suffering from high rate of soil erosion, however, vegetation can
effectively control erosion but erosion reduction exhibits low
effectiveness on vegetation development. Vegetation in the area
is not stable and management is always needed to maintain the
vegetation. Copyright by Science in China Press 2005.
HYDROLOGY
1881 Using stable isotope tracers to assess hydrological flow
paths, residence times and landscape influences in a nested
mesoscale catchment
Rodgers P., Soulsby C., Waldron S. and Tetzlaff D. Hydrology
and Earth System Sciences 2005 9/3 (139-155)
18 O measurements in precipitation and stream waters were used
to investigate hydrological flow paths and residence times at
nested spatial scales in the mesoscale (233 km2 ) River Feugh
catchment in the northeast of Scotland over the 2001-2002 hydrological year. Precipitation 18 O exhibited strong seasonal
variation, which although significantly damped within the catchment, was reflected in stream water at six sampling sites. This
360
HYDROLOGY
allowed 18 O variations to be used to infer the relative influence
of soil-derived storm flows with a seasonally variable isotopic
signature, and groundwater of apparently more constant isotopic
composition. Periodic regression analysis was then used to examine the sub-catchment difference using an exponential flow model
to provide indicative estimates of mean stream water residence
times, which varied between approximately 3 and 14 months.
This showed that the effects of increasing scale on estimated
mean stream water residence time was minimal beyond that of
the smallest (ca. 1 km2 ) headwater catchment scale. Instead, the
interaction of catchment soil cover and topography appeared to
be the dominant controlling influence. Where sub-catchments
had extensive peat coverage, responsive hydrological pathways
produced seasonally variable 18 O signatures in runoff with short
mean residence times (ca. 3 months). In contrast, areas dominated by steeper slopes, more freely draining soils and larger
groundwater storage in shallow valley-bottom aquifers, deeper
flow paths allow for more effective mixing and damping of 18 O
indicating longer residence times (> 12 months). These insights
from 18 O measurements extend the hydrological understanding
of the Feugh catchment gained from previous geochemical tracer
studies, and demonstrate the utility of isotope tracers in investigating the interaction of hydrological processes and catchment
characteristics at larger spatial scales. В© 2005 Author(s). This
work is licensed under a Creative Commons License.
1882 Discussion on hydrologic scaling (Chinese)
Zhong Y., Jin C. and Pei T. Chinese Journal of Applied Ecology
2005 16/8 (1537-1540)
Hydrologic scaling is the hotspot and frontier of todayвЂ™s hydrologic research, which includes three different meanings distinguished from each other, i.e., process scale, observation scale and
modelling scale. As a characteristic of hydrologic scale, dominant process scale has been paid more attention. Hydrologic
scaling includes the scaling of hydrologic models, parameters,
state variables and inputs, which owns special research methods
respectively. The difficulty of hydrologic scaling mainly comes
from the organized complexity of hydrologic systems, the heterogeneity and variability in space and time, and the insufficiency
of data. The ubiquitous self-similarity of natural river networks
makes itself an important part of hydrologic scaling research.
The combination of various techniques and theories is needed to
motivate hydrologic scaling research.
Precipitation assessment
1883 Composition of wet and bulk deposition in Erzurum,
Turkey
Bayraktar H. and Turalioglu F.S. Chemosphere 2005 59/11
(1537-1546)
Seasonal variations in the chemical characteristics of wet and
bulk deposition samples collected in Erzurum were investigated
for the period March 2002-January 2003. Major cations (Ca2+ ,
K+ , Mg 2+ ) and major anions (SO24 , NO 3 ) were determined in
bulk and wet deposition samples; pH was also measured in wet
deposition. The average pH of the wet deposition at Erzurum
was 6.6 due to extensive neutralization of the acidity. A strong
relationship between pH and SO24 concentrations was observed
in all seasons; however, only a weak relationship was found
between pH and NO-3 . On a seasonal basis, the correlation
between Ca2+ and SO24 concentrations was stronger in winter
than in summer. Seasonal variations of ions were examined
in both wet and bulk deposition samples. Although maximum
concentrations of anions generally occurred during winter and
spring, cation concentrations peaked in summer for both wet and
bulk deposition. Results indicated that Ca2+ was the dominant
cation and SO24 the dominant anion in all deposition samples
at Erzurum. Even though correlations among the crustal ions
(calcium, magnesium and potassium) were high, the relationship
between anthropogenic ions (sulfate and nitrate) was less clear
in bulk deposition. В© 2005 Elsevier Ltd. All rights reserved.
1884 Error characteristics of rainfall measurements by collocated Joss-Waldvogel disdrometers
Tokay A., Bashor P.G. and Wolff K.R. Journal of Atmospheric
and Oceanic Technology 2005 22/5 (513-527)
Error characteristics of rainfall measurements were studied using
six collocated Joss- Waldvogel (JW) disdrometers that are located
at NASAвЂ™s Wallops Flight Facility. The six disdrometer means
of rain rate R, reflectivity Z, and differential reflectivity ZDR, for
a given minute were considered as a reference. The maximum
deviations of R, Z, and ZDR from the mean in a rain event
were 0.6 mm h-1 , 1.3 dB, and 0.05 dB, respectively. Rainfall
statistics were then examined between disdrometer pairs. The
root-mean-square (rms) difference of R, Z, and ZDR between
paired disdrometers in a rain event were as high as 3.2 mm
h-1 , 3.7 dB, and 0.3 dB, respectively. The rms difference of R
and ZDR were even higher when the disdrometer observations
were stratified based on reflectivity intervals. The differences in
disdrometer rainfall measurements have a potential impact when
the disdrometers are considered as calibration tools for vertically
pointing and scanning radars. The differences between the disdrometer measurements also result in differences in coefficients
and exponents of the derived relations between radar parameters
and rain rate. Among the four different relations between radar
parameters and rain rate, the absolute difference in rain rate R
from two different JW disdrometers was highest in R(ZH, ZDR)
and lowest in R(KDP, ZDR). The other two relations were R(Z)
and R(KDP). The R increases with increasing horizontally polarized reflectivity ZH, and differential specific phase KDP in
both single- and dual-parameter rainfall estimators, while the
R increases with decreasing ZDR in dual-parameter rainfall
estimators. Several sources of JW disdrometer malfunctions
were also presented. The hardware problems were the leading
cause for the malfunction of the JW disdrometers, as identified by
the manufacturer. A single JW disdrometer could have inherent
measurement errors that can only be identified in the presence of
collocated (preferably two) rain-measuring instruments. В© 2005
American Meteorological Society.
1885 Investigation of the rainfall variability in central
Tunisia
Kingumbi A., Bargaoui Z. and Hubert P. Hydrological Sciences
Journal 2005 50/3 (493-508)
The decrease in runoff of the Merguellil basin, Tunisia recorded
during the decade 1989-1998 led to the study of several time
series derived from daily rainfall. It was found that variability characteristics related to daily rainfall greater than 30 mm
are significantly different among successive time periods. In
addition, the probability distributions of these rains, recorded
at different raingauge sites, are significantly different between
the period 1976-1989 and the prior and posterior observation
periods. Furthermore, the surface covered by daily rains greater
than 30 mm decreased between 1976 and 1989. It was also
noted that the probability distributions of the surfaces covered
changed significantly after 1976. The combination of human
action and pluviometric variability (rainfall increase in the period 1989-1998, notably the increase in the number of days of
rainfall greater than 30 mm) may explain the decrease in runoff
of Merguellil Wadi. Copyright В© 2005 IAHS Press.
1886 Comparison of rain gauge observations with modeled
precipitation over Cyprus using contiguous rain area analysis
Tartaglione N., Mariani S., Accadia C. et al. Atmospheric Chemistry and Physics 2005 5/8 (2147-2154)
Verification of modeled rainfall with precipitation observed by
a rain gauge network has been performed in a case study over
the Cyprus Island. Cyprus has a relatively dense rain gauge network. The applied verification method is the Contiguous Rain
Area (CRA) analysis. Some drawbacks of the CRA method are
pointed out when it is applied to such a case study. Impact on the
CRA results, when considering different dimensions of the verification sub-domain and different types of indicators (correlation
and mean square error) used in the comparison, are discussed.
Results indicate that care should be taken when verification of
modeled rainfall is performed over a domain smaller than the
model one. В© 2005 Author(s). This work is licensed under a
Creative Commons License.
HYDROLOGY
1887 A model for estimation of rain rate on tropical land
from TRMM microwave imager radiometer observations
Prabhakara C., Iacovazzi R., Yoo J.- M. and Kim K.- M. Journal
of the Meteorological Society of Japan 2005 83/4 (595-609)
Over the tropical land regions scatter plots of the rain rate (RPR ),
deduced from the TRMM Precipitation Radar (PR) versus the
observed 85 GHz brightness temperature (T85v ) made by the
TRMM Microwave Imager (TMI) radiometer, for a period of
a season over a given geographic region of 3В° 5В° (lat Ion),
indicate that there are two maxima in rain rate. One strong
maximum occurs when T85v has a value of about 220 K, and the
other weaker one when T85v is much colder 150 K. Also these
two maxima are vividly revealed in plots of RPR vs. (T19v -T37v ).
The strong maximum occurs when (T19v -T37v ) is 20 K and the
weaker maximum when it is greater than 40 K. Together with
the help of a) earlier investigations based on airborne Doppler
Radar observations and b) radiative transfer theoretical simulations, we infer the strong maximum is a result of relatively weak
scattering due to super cooled rain drops and water coated ice
hydrometeors associated with a developing thunderstorm (Cb)
that has a strong updraft. The other maximum is associated
with strong scattering due to ice particles that are formed when
the updraft collapses and the rain from the Cb is transitioning
from convective type to stratiform type. Incorporating these
ideas with a view to improve the estimation of rain rate from
existing operational method applicable to the tropical land areas,
we have developed a rain retrieval model. This model utilizes
two parameters, that have a horizontal scale of 20 km, deduced
from the TMI measurements at 10, 19, 21 and 37 GHz(T10v , T19v ,
T21v , T37v ). The third parameter in the model, namely the mean
horizontal gradient <dT85v /dr> (K km-1 ) within the 20 km scale,
is deduced from TMI measurements at 85 GHz that have the
scale of 5 km. Utilizing these parameters our retrieval model is
formulated to yield instantaneous rain rate on a scale of 20 km.
This retrieval model is initially tuned with the help of a limited
amount of PR rain rate. After initial tuning, the model is applied
to widely different tropical land areas, and for different seasons.
Our estimates of instantaneous rain rate, on a scale of 20 km, and
seasonal averages on a scale of 3В° 5В° (lat Ion) agree better
with PR than that given by the operational TMI rain retrievals.
В© 2005, Meteorological Society of Japan.
1888 Accuracy verification of spaceborne radar estimates of
rain rate
Amitai E., Liao L., Llort X. and Meneghini R. Atmospheric
Science Letters 2005 6/1 (2-6)
The distribution of rain rate is of great concern for many hydrological applications. Probability distribution functions (pdf) of
rain rate can now be obtained from spaceborne radar observations. Effort to evaluate these pdfs using ground observations is
described. Copyright В© 2005 Royal Meteorological Society.
1889 Semi-operational rainfall observations with X-band
multi-parameter radar
Maki M., Iwanami K., Misumi R. et al. Atmospheric Science
Letters 2005 6/1 (12-18)
Three-year semi-operational observations of rainfall distributions with NIED X-band multi-parameter (or polarimetric) radar
started in the Kanto area of Japan from July 2003. The purposes
and outlines of the radar observations with networks of rain
gauges and disdrometers for ground validations are described.
Preliminary results of validation analysis of polarimetric rain
rate estimators show the usefulness of X-band multi-parameter
radar for hydrological and meteorological applications in a small
area. Copyright В© 2005 Royal Meteorological Society.
1890 Combining radar and rain gauge rainfall estimates
using conditional merging
Sinclair S. and Pegram G. Atmospheric Science Letters 2005 6/1
(19-22)
The HydrologistвЂ™s traditional tool for measuring rainfall is the
rain gauge. Rain gauges are relatively cheap, easy to maintain
and provide a direct and suitably accurate estimate of rainfall
at a point. What rain gauges fail to capture well is the spatial
variability of rainfall with time, an important aspect for the credible modelling of a catchmentвЂ™s response to rainfall. This spatial
361
variability is particularly evident at short timescales of up to several days. As the period of accumulation increases, the expected
spatial variability is reduced and rain gauges provide improved
spatial rainfall estimates. Because of the fractal variability of
rainfall in space, simple interpolation between rain gauges does
not provide an accurate estimate of the true spatial rainfall field,
at short time scales. Weather radar provides (with a single instrument) a highly detailed representation of the spatial structure and
temporal evolution of rainfall over a large area. Estimated rainfall rates are derived indirectly from measurements of reflectivity
and are therefore subject to a combination of systematic and random errors. This article describes a recently proposed merging
technique and presents an application to simulated rainfall fields.
The technique employed is Conditional Merging (Ehret, 2002),
which makes use of Kriging to extract the optimal information
content from the observed data. A mean field based on the Kriged rain gauge data is adopted, while the spatial detail from the
radar is retained, reducing bias, but keeping the spatial variability
observed by the radar. The variance of the estimate is reduced
in the vicinity of the gauges where they are able to provide good
information on the true rainfall field. Copyright В© 2005 Royal
Meteorological Society.
1891 Rainfall modeling for integrating radar information
into hydrological model
Morin E., Goodrich D.C., Maddox R.A. et al. Atmospheric
Science Letters 2005 6/1 (23-30)
A spatial rainfall model was applied to radar data of air mass
thunderstorms to yield a rainstorm representation as a set of
convective rain cells. The modeled rainfall was used as input
into hydrological model, instead of the standard radar-grid data.
This approach allows a comprehensive linkage between runoff
responses and rainfall structures. Copyright В© 2005 Royal Meteorological Society.
1892 Radar rainfall estimation in the New Zealand context
Gray W. and Larsen H. Atmospheric Science Letters 2005 6/1
(31-34)
Difficulties commonly encountered in precipitation measurement
by radar include errors from radar reflections from the surface, errors in extrapolating from measurements aloft, and errors through
inadequately sampling a fluctuating signal. These error sources
are discussed, along with the skill of the solutions that have been
implemented. Copyright В© 2005 Royal Meteorological Society.
1893 Nowcasting for New Zealand
Gray W., Larsen H. and Seed A. Atmospheric Science Letters
2005 6/1 (35-39)
Techniques are assessed for analysing the skill with which
weather radar data can be extrapolated to provide short-term
rainfall forecasts. In addition to visual inspection, forecast skill
is assessed using catchment-averaged statistics - comparing analyses with rain gauge averages, forecasts with analyses and
forecast river flow with measured flow. Copyright В© 2005 Royal
Meteorological Society.
1894 Assessing error in hydrological and hydraulic model
output flows
Robbins G.L. and Collier C.G. Atmospheric Science Letters 2005
6/1 (47-53)
A hydraulic model of an urban drainage system with a Bayesian
post processor is used to assess the uncertainty in model output
flows associated with the use of measurements of rainfall made
using raingauges, microwave link attenuation measurements and
weather radar. Copyright В© 2005 Royal Meteorological Society.
1895 Errors in surface rainfall rates retrieved from radar
due to wind-drift
Lack S.A. and Fox N.I. Atmospheric Science Letters 2005 6/1
(71-77)
This article describes a series of experiments based on real data
wherein the advection of the precipitation below the radar-sampled volume is estimated using Doppler radar determined wind
fields. The experiments show that even at standard resolutions
of 2 km the error can be extensive, and at higher resolutions
and greater ranges (higher beam elevations) the errors become
362
HYDROLOGY
very large. Errors are assessed using different Z-R relationships
and resolutions as high as 0.5 km. Copyright В© 2005 Royal
Meteorological Society.
1896 Use of a stochastic precipitation nowcast scheme for
fluvial flood forecasting and warning
Pierce C., Bowler N., Seed A. et al. Atmospheric Science Letters
2005 6/1 (78-83)
In collaboration with the Bureau of Meteorology (Melbourne,
Australia), the Met Office (Joint Centre for Hydro-Meteorological Research, UK) has developed a stochastic precipitation nowcast scheme, designed to model and predict the PDF of surface
rain rate and rain accumulation in space and time. Here we
demonstrate the range of probabilistic products generated by the
scheme, and their potential applications for fluvial flood forecasting and warning. With the aid of a hydrological model (the
PDM), we consider the use of ensembles of predicted catchment
rain accumulation in evaluating the range of possible river flow responses from a given catchment. When employed in conjunction
with a catchment specific, cost-based decision-making model,
we highlight the value of PDFs of forecast catchment rainfall
accumulation and river flow as an aid to objective decision making within the flood warning process. В© Crown Copyright 2005.
Reproduced with the permission of Her MajestyвЂ™s Stationery
Office. Published by John Wiley & Sons, Ltd.
1897 Virtual CSU-CHILL radar: The VCHILL
Chandrasekar V., Cho Y.- G., Brunkow D. and Jayasumana A.
Journal of Atmospheric and Oceanic Technology 2005 22/7 (979987)
The Virtual CHILL (VCHILL) system makes it possible to transfer the educational and research experience of the Colorado State
University dual polarization radar to remote locations over the
Internet. The VCHILL operation includes remote control of
radar and display of radar images, as well as the ability to locally process high-bandwidth radar data transferred over data
networks. The low-bandwidth VCHILL operation allows the
distant users to access the archived and real-time data estimated
at the radar site and simultaneously display them on their local systems. A parallel receiver was developed exclusively for
the high-bandwidth VCHILL. End-system architectures were
designed to accommodate the demands of the high-bandwidth
VCHILL operations in real time. A graphic user interface was
also developed with the objective of easy installation and usage
at various end-user institutions. The VCHILL not only expands
the education experience provided by the radar system, but also
stimulates the development of innovative research applications
for atmospheric remote sensing. The VCHILL is being used by
several universities for research and education. В© 2005 American
Meteorological Society.
1898 Regional rainfall frequency analysis for the state of
Michigan
Trefry C.M., Watkins Jr. D.W. and Johnson D. Journal of Hydrologic Engineering 2005 10/6 (437-449)
Effective storm water management plans depend on reliable rainfall intensity-duration-frequency (IDF) relationships. Due to the
perception of high-intensity rainfall events as occurring more
frequently than expected, the Michigan Dept. of Transportation
(MDOT) commissioned a study to update rainfall IDF estimates
for each of seven durations (1, 2, 3, 6, 12, 18, and 24 h) and
six recurrence intervals (2, 5, 10, 25, 50, and 100 years). In
contrast to a traditional at-site frequency analysis using method
of moments estimators, this study applied a regional frequency
analysis approach based on L-moments. Data were compiled
from 76 hourly recording stations and 152 daily recording stations, and trend and outlier analyses were conducted on both
annual maximum series (AMS) and partial duration series (PDS)
data. With the entire state considered a homogeneous region, two
regional index flood models were applied: a generalized Pareto
distribution fit to PDS data (PDS/GPA model), and a generalized
extreme value distribution fit to AMS data (AMS/GEV model).
Verification of results indicated that the revised rainfall IDF estimates provide more reliable values than those previously used.
Journal of Hydrologic Engineering В© ASCE.
1899 Short duration rainfall frequency analysis in Michigan
using scale-invariance assumptions
Gerold L.A. and Watkins Jr. D.W. Journal of Hydrologic Engineering 2005 10/6 (450-457)
Intensity-duration-frequency (IDF) estimates are important statistical summaries of precipitation records used for hydrologic
engineering design. To make use of recent data and modern
statistical methods, the IDF estimates for the state of Michigan
have been updated using a regional frequency analysis procedure.
Since short duration data (less than one hour) are only available in
the Detroit metropolitan area, scale-invariance assumptions are
used to estimate short-duration IDF values throughout the state.
Both simple scaling and multiscaling models are considered,
and the simple scaling model is selected for practical purposes.
Verification results indicate that the short-duration estimates are
consistent with historical observations. Journal of Hydrologic
Engineering В© ASCE.
1900 Reconstructing solid precipitation from snow depth
measurements and a land surface model
Cherry J.E., Tremblay L.B., DВґery S.J. and Stieglitz M. Water
Resources Research 2005 41/9 (1-15)
[1] The amount and distribution of snowfall in the Arctic has
significant effects on global climate. However, measurements
of snowfall from gauges are strongly biased. A new method is
described for reconstructing snowfall from observed snow depth
records, meteorological observations, and running the NASA
Seasonal-to-Interannual Prediction Project Catchment Land Surface Model (NSIPP CLSM) in an inverse mode. This method is
developed and tested with observations from Reynolds Creek Experimental Watershed. Results show snowfall can be accurately
reconstructed on the basis of how much snow must have fallen
to produce the observed snow depth. The mean cumulative error
(bias) of the reconstructed precipitation for 11 snow seasons is 29
mm snow water equivalent (SWE) for the corrected gauge measurement compared to -77 mm SWE for the precipitation from
the corrected show gauges. This means the root-mean-square
error of reconstructed solid precipitation is 30% less than that of
gauge corrections. The intended application of this method is the
pan-Arctic landmass, where estimates of snowfall are highly uncertain but where more than 60 years of historical snow depth and
air temperature records exist. Copyright 2005 by the American
Geophysical Union.
1901 Empirical mode decomposition in 2-D space and time:
A tool for space-time rainfall analysis and nowcasting
Sinclair S. and Pegram G.G.S. Hydrology and Earth System Sciences 2005 9/3 (127-137)
A data-driven method for extracting temporally persistent information, at different spatial scales, from rainfall data (as measured
by radar/ satellite) is described, which extends the Empirical
Mode Decomposition (EMD) algorithm into two dimensions.
The EMD technique is used here to decompose spatial rainfall
data into a sequence of high through to low frequency components. This process is equivalent to the application of successive
low-pass spatial filters, but based on the observed properties of the
data rather than the predetermined basis functions used in traditional Fourier or Wavelet decompositions. It has been suggested
in the literature that the lower frequency components (those with
large spatial extent) of spatial rainfall data exhibit greater temporal persistence than the higher frequency ones. This idea is
explored here in the context of Empirical Mode Decomposition.
The paper focuses on the implementation and development of
the two-dimensional extension to the EMD algorithm and itвЂ™s
application to radar rainfall data, as well as examining temporal persistence in the data at different spatial scales. В© 2005
Author(s). This work is licensed under a Creative Commons
License.
1902 Archival precipitation data set for the Mississippi River
Basin: Evaluation
Nelson B.R., Krajewski W.F., Smith J.A. et al. Geophysical
Research Letters 2005 32/18 (1-5)
The goals of the Global Energy and Water Cycle Experiment
Continental-Scale International Project (GCIP) point to the need
fo high resolution data sets on all elements of the land surface and
atmospheric hydrologic cycle. A high resolution precipitation
HYDROLOGY
data set has been derived from radar reflectivity observations
taken from the National Weather Service WSR-88D radars in
the continental U.S. To evaluate the product the authors provide
several case studies of radar-rain gauge comparisons at locations
throughout the Mississippi River Basin. They present bias, root
mean square difference, fractional standard difference, and correlation coefficient statistics for radar-rain gauge comparisons
for the hourly, daily, monthly, yearly and warm season temporal scale. These point (gauge) and pixel (radar) comparisons
show large discrepancies at the hourly scale, on the order of
600-800%. An evaluation of the differences associated with
temporally integrated estimates shows marked reduction in these
discrepancies. At the long-term (warm season), these reduce to
about 10%. An estimate of the difference in the comparison of
the long term accumulation of gridded gauge based estimates and
radar estimates at 0.25В° 0.25В° shows values in the range of 20%
but decrease to about 15% after applying filtering techniques in
the basin-wide comparisons. Copyright 2005 by the American
Geophysical Union.
Precipitation quality
1903 Trace metals in bulk precipitation and throughfall in
a suburban area of Japan
Hou H., Takamatsu T., Koshikawa M.K. and Hosomi M. Atmospheric Environment 2005 39/20 (3583-3595)
Throughfall and bulk precipitation samples were collected
monthly for 1.5 years over bare land and under canopies of
Japanese cedar (Cryptomeria japonica), Japanese red pine (Pinus densiflora), Japanese cypress (Chamaecyparis obtusa), and
bamboo-leafed oak (Quercus myrsinaefolia) in a suburban area
of Japan. Samples were analyzed for dissolved Al, Mn, Fe, Cu,
Zn, Ag, In, Sn, Sb and Bi by ICP-AES and ICP-MS. The metal
concentrations were higher in throughfall, especially that of C.
japonica, than bulk precipitation. Enrichment ratios (ERs: ratios
of metal concentrations in throughfall to those in bulk precipitation) ranged from 2.5 (Zn) to 5.3 (Ag) (3.9 on average), and
ERs for slightly soluble metals were generally higher than those
for easily soluble metals. Concentrations of Mn, Fe, Cu, and Zn
accounted for 99% of the total concentration of heavy metals in
rainwater, whereas those of rare metals such as Ag, In, Sn, and
Bi totaled <0.23%. Average concentrations of rare metals were
0.002 and 0.010 g l-1 for Ag, 0.001 and 0.005 g l -1 for In,
0.062 and 0.21 g l-1 for Sn, and 0.006 and 0.023 g l-1 for Bi in
bulk precipitation and throughfall, respectively. The metal concentrations in rainwater were negatively correlated to the volume
of rainwater, indicating that washout is the main mechanism that
incorporates metals into rainwater. From the enrichment factors,
that is, (X/Al)rain /(X/Al)crust , metals other than Fe were shown to
be more enriched in rainwater than in the EarthвЂ™s crust, including
those present as a result of leaching from soil dust (Mn) and from
anthropogenic sources (Cu, Zn, Ag, In, Sn, Sb, and Bi). В© 2005
Elsevier Ltd. All rights reserved.
1904 Enhanced dissolution of volatile organic compounds
into urban dew water collected in Yokohama, Japan
Okochi H., Kataniwa M., Sugimoto D. and Igawa M. Atmospheric Environment 2005 39/33 (6027-6036)
Simultaneous sampling of six chlorinated hydrocarbons (CHs)
and five monocyclic aromatic hydrocarbons (MAHs) in dew water and in the ambient air was performed from 1998 to 2000
in Yokohama, Japan. Dichloromethane (volume-weighted mean
concentration (VWM): 2.43 nM) and trichloroethylene (VWM:
2.91 nM) were abundant among CHs in dew water, while toluene
(VWM: 9.69 nM) and p-dichlorobenzene (VWM: 6.06 nM) were
abundant among MAHs. The contribution of total measured
volatile organic compounds (VOCs) concentration to dissolved
organic carbon (DOC) concentration in dew water was only 0.02
wt% on average. The concentrations of VOCs except for dichloromethane and benzene in dew water were several hundred
times higher than those in rainwater collected at the same site.
In particular more hydrophobic VOCs with higher octanol-water
partition coefficient KOW tended to be concentrated in dew water, indicating that urban dew water has stronger hydrophobicity
than rainwater. Dew water contained higher amounts of VOCs
363
than would have been expected from the ambient gas-phase concentrations and HenryвЂ™s law constants. The enrichment factors,
which were defined as the ratio of the observed concentration to
the estimated, ranged from 6.98 (for dichloromethane) to 62.7
(for trichloroethylene) on average. Relatively high correlations
(r>0.55) between the enrichment factors of highly hydrophobic
VOCs (Kow >103 ) and the ratios of DOC to total inorganic ion
concentration (TIC), which could be a potential surrogate of surface tension for urban dew water, indicated that the existence of
any dissolved organic compounds, which could reduce the surface tension, in dew water also caused the enrichment of highly
hydrophobic VOCs. В© 2005 Elsevier Ltd. All rights reserved.
1905 Study of chemical composition in wet atmospheric precipitation in Eshidiya area, Jordan
Al-Khashman O.A. Atmospheric Environment 2005 39/33 (61756183)
The present study investigated the chemical composition of wet
atmospheric precipitation samples in the Eshidiya area in south
Jordan. The samples were analyzed from October 2003 to May
2004. All samples were analyzed for major ions (Cl- , NO3-,
HCO3-, SO42-, Na+ , K+ , Ca 2+ , Mg2+ and NH4+) and trace
metals (Cd, Cu, Pb, Zn, Fe and Ni). The highest concentration
of elements is observed at the beginning of the rainfall season
when large amounts of dust accumulate in the atmosphere scavenged by rain. The daily sample pH values ranged from 5.33 to
7.90 with a median value of 6.65 0.68. Rain water quality is
characterized by low salinity and neutralized pH. High values of
pH were attributed to the neutralization by natural alkaline local
dusts which contain a large fraction of calcite and dolomite. The
major ions in rainwater samples showed high Ca 2+ , HCO3-,
SO42-, Cl- and Mg2+ concentrations. For trace metals, the study
identified that the origin of these metals from local anthropogenic
activities (from soil and phosphate mine, heating activities during
the cold period of year (January to April) and the anthropogenic
activities. In general, the results of this study suggest that the
rainwater chemistry is strongly influenced by natural sources
rather than anthropogenic and marine sources. В© 2005 Elsevier
Ltd. All rights reserved.
1906 A comparison of snow quality in two swedish municipalities-Lule and Sundsvall
Reinosdotter K. and Viklander M. Water, Air, and Soil Pollution
2005 167/1-4 (3-16)
In municipal planning of locations of snow deposits and investigations of the environmental effects of snow dumping, the partitioning of contaminants between particulate and dissolved matter
is of great importance. This paper compares snow quality in two
Swedish municipalities - Lule and Sundsvall over time. The two
municipalities have differences in used de-icing material and
winter conditions. Because Lule has a longer winter season and
a lower average temperature, higher accumulations of chemicals
were found in Lule than in Sundsvall. A multiple regression
analysis indicated relationships between the dissolved fraction
of heavy metals and the concentration of suspended solids and
chloride. В© Springer 2005.
1907 Fog- and rainwater chemistry in the tropical seasonal
rain forest of Xishuangbanna, southwest China
Wen J.L., Yi P.Z., Hong M.L. et al. Water, Air, and Soil Pollution
2005 167/1-4 (295-309)
Fogwater, fog drip and rainwater chemistry were examined at a
tropical seasonal rain forest in Xishuangbanna, southwest China
between November 2001 and October 2002. During the period of
observation, 204 days with the occurrence of radiation fog were
observed and the total duration of fog was 1949 h, of which 1618
h occurred in the dry season (November to April), accounting for
37.0% of the time during the season. The mean pH of fogwater,
fog drip and rainwater were 6.78, 7.30, and 6.13, respectively.
The ion with the highest concentration for fog- and rainwater was
HCO3 - , which amounted to 85.2 and 37.3 eq l-1 , followed by
Ca2+ , Mg2+ and NH4 + . Concentrations of NO3 - , HCO3 - , NH4
+ , Ca2+ , and K+ in fogwater samples collected in the dry season
were significantly greater when compared to those collected in
the rainy season. It was found that the ionic concentrations in fog
drip were higher than those in fogwater, except for NH4 + and H+ ,
364
HYDROLOGY
which was attributed to the washout of the soil- and ash-oriented
ions deposited on the leaves and the alkaline ionic emissions by
the leaves, since biomass burns are very common in the region
and nearby road was widening. В© Springer 2005.
1908 Stable isotopes in precipitation recording South American summer monsoon and ENSO variability: Observations
and model results
Vuille M. and Werner M. Climate Dynamics 2005 25/4 (401-413)
The South American Summer Monsoon (SASM) is a prominent
feature of summertime climate over South America and has been
identified in a number of paleoclimatic records from across the
continent, including records based on stable isotopes. The relationship between the stable isotopic composition of precipitation
and interannual variations in monsoon strength, however, has
received little attention so far. Here we investigate how variations in the intensity of the SASM influence 18 O in precipitation
based on both observational data and Atmospheric General Circulation Model (AGCM) simulations. An index of vertical wind
shear over the SASM entrance (low level) and exit (upper level)
region over the western equatorial Atlantic is used to define interannual variations in summer monsoon strength. This index is
closely correlated with variations in deep convection over tropical and subtropical South America during the mature stage of the
SASM. Observational data from the International Atomic Energy
Agency-Global Network of Isotopes in Precipitation (IAEAGNIP) and from tropical ice cores show a significant negative
association between 18 O and SASM strength over the Amazon
basin, SE South America and the central Andes. The more
depleted stable isotopic values during intense monsoon seasons
are consistent with the so-called "amount effect", often observed
in tropical regions. In many locations, however, our results indicate that the moisture transport history and the degree of rainout
upstream may be more important factors explaining interannual
variations in 18 O. In many locations the stable isotopic composition is closely related to El NiЛњno-Southern Oscillation (ENSO),
even though the moisture source is located over the tropical Atlantic and precipitation is the result of the southward expansion
and intensification of the SASM during austral summer. ENSO
induces significant atmospheric circulation anomalies over tropical South America, which affect both SASM precipitation and
18 O variability. Therefore many regions show a weakened relationship between SASM and 18 O, once the SASM signal is
decomposed into its ENSO-, and non-ENSO-related variance. В©
Springer-Verlag 2005.
1909 Review of precipitation monitoring studies in India A search for regional patterns
Kulshrestha U.C., Granat L., Engardt M. and Rodhe H. Atmospheric Environment 2005 39/38 (7403-7419)
This study is a review of rain chemistry measurements reported
in India. Data from nearly 100 stations were reviewed with
regard to sampling location, sampling method and chemical analyses. Some characteristic differences were found between the
concentrations in different environments in line with known distributions of emissions. This was most clearly seen for SO4 2with median concentration increasing from rural and suburban to
urban and industrial environments, with concentrations of HCO3
- and H+ varying the opposite way. Ca2+ concentration was higher
in suburban and industrial environments compared to rural and
urban. Concentration of NH+4 was lower in rural than in the other
locations. Sea salt concentration (Na+ and Cl - in approximately
constant proportion) was higher in urban than in rural locations at
the same distance from the sea. The reported data from rural and
suburban locations were used to derive large-scale concentration
fields over India. With knowledge of emission fields and with the
aid of output from a regional transport model it was possible to
see some limited spatial resemblance between modelled and observed concentrations in cases of NH4 + , NO-3 and SO24 . For soil
dust, current models are very crude but here some resemblance
could be seen: primarily limited spatial resemblance with Ca2+ ,
pH and HCO-3 with generally increasing values towards NW.
Four sites, at least two of them located in forested environments,
had a mean rainwater pH close to neutral (concentration of H+
and HCO -3 about equal). Other sites had on average an excess
of HCO-3 , becoming very substantial in the direction of the Thar
Desert in NW India. With this review we conclude that there is
a need to better assure the quality of the data with regard to sampling methods, chemical analyses and spatial representativeness.
В© 2005 Elsevier Ltd. All rights reserved.
1910 Chemical characterization of fog and rain water collected at the eastern Andes cordillera
Beiderwieden E., Wrzesinsky T. and Klemm O. Hydrology and
Earth System Sciences 2005 9/3 (185-191)
During a three month period in 2003 and 2004, the chemistry of
fog and rainwater were studied at the "El Tiro" site in a tropical
mountain forest ecosystem in Ecuador, South America. The
fogwater samples were collected using a passive fog collector,
and for the rain water, a standard rain sampler was employed.
For all samples, electric conductivity, pH, and the concentrations
2of NH+4 , K+ , Na+ , Ca2+ , Mg2+ , Cl- , NO-3 , PO34 , and SO4 were
measured. For each fog sample, a 5 day back trajectory was
calculated by the use of the HYSPLIT model. Two types of
trajectories occurred. One type was characterized by advection
of air masses from the East over the Amazonian basin, the other
trajectory arrived one from the West after significant travel time
over the Pacific Ocean. We found considerably higher ion concentrations in fogwater samples than in rain samples. Median
pH values are 4.58 for fog water, and 5.26 for the rain samples,
respectively. The median electric conductivity was 23 S cm-1
for the fog and 6 S cm-1 for the rain. The continent samples
exhibit higher concentrations of most ions as compared to the
pacific samples, but these differences could not be detected statistically. В© 2005 Author(s). This work is licensed under a
Creative Commons License.
1911 Precipitation scavenging of 7 Be and 137 Cs radionuclides in air
Ioannidou A. and Papastefanou C. Journal of Environmental Radioactivity 2006 85/1 (121-136)
Atmospheric depositional fluxes of the naturally occurring 7 Be
of cosmogenic origin and 137 Cs from fallout of the Chernobyl
accident were measured over a 6-year period (January 1987-December 1992) at Thessaloniki, Greece (40В°38 N, 22В°58 E). Total precipitation accumulation during 1987-1992 varied between
33.7 cm and 65.2 cm, reflecting a relatively dry (precipitationfree) climate. The activity concentrations of 7 Be and 137 Cs in
rainwater depended on the precipitation rate, being higher for
low precipitation rates and lesser for high precipitation rates.
137 Cs was removed by rain and snow more efficiently than 7 Be.
Snowfall was more efficient than rainfall in removing the radionuclides from the atmosphere. The annual bulk depositional
fluxes of 7 Be varied between 477 and 1133 Bq m-2 y-1 and this
variability was attributed to the amount of precipitation and the
variations of the atmospheric concentrations of 7 Be. The annual
bulk depositional fluxes of 137 Cs showed a significant decrease
over time from 1987 to 1992, resulting in a removal half-life
of 1.33 years. The presence of 137 Cs in air, and therefore in
rainwater and snow, long after the Chernobyl accident (26 April
1986) was mainly due to the resuspension process. The normalized depositional fluxes of both radionuclides showed maximal
values during the spring season where the maximum amount of
precipitation occurred. The relatively high positive correlation
between 7 Be and 137 Cs normalized depositional fluxes indicates
that the scavenging process of local precipitation controlled the
fluxes of both radionuclides. The dry depositional flux of 7 Be
was less than 9.37% of total (wet and dry) depositional flux.
The fraction of dry-to-total depositional flux of 137 Cs was much
higher than that of 7 Be, due to the resuspended soil. В© 2005
Elsevier Ltd. All rights reserved.
Interception, throughfall and
stemflow
1912 Retention and translocation of foliar applied 239,240 Pu
and 241 Am, as compared to 137 Cs and 85 Sr, into bean plants
(Phaseolus vulgaris)
Henner P., Colle C. and Morello M. Journal of Environmental
Radioactivity 2005 83/2 (213-229)
HYDROLOGY
241 Am, 239,240 Pu, 137 Cs
85 Sr
and
was evaluated
Foliar transfer of
after contamination of bean plants (Phaseolus vulgaris) at the
flowering development stage, by soaking their first two trifoliate leaves into contaminated solutions. Initial retentions of
241 Am (27%) and 239,240 Pu (37%) were higher than those of
137 Cs and 85 Sr (10-15%). Mean fraction of retained activity
redistributed among bean organs was higher for 137 Cs (20.3%)
than for 239,240 Pu (2.2%), 241 Am (1%) or 85 Sr (0.1%). Mean leafto-pod translocation factors (Bq kg-1 dry weight pod/Bq kg-1 dry
weight contaminated leaves) were 5.0 10 -4 for 241 Am, 2.7
10-6 for 239,240 Pu, 5.4 10-2 for 137 Cs and 3.6 10-4 for 85 Sr.
Caesium was mainly recovered in pods (12.8%). Americium and
strontium were uniformly redistributed among leaves, stems and
pods. Plutonium showed preferential redistribution in oldest bean
organs, leaves and stems, and very little redistribution in forming
pods. Results for americium and plutonium were compared to
those of strontium and caesium to evaluate the consistency of the
attribution of behaviour of strontium to transuranium elements
towards foliar transfer, based on translocation factors, as stated
in two radioecological models, ECOSYS-87 and ASTRAL. В©
2005 Elsevier Ltd. All rights reserved.
1913 Liquid and chemical fluxes in precipitation, throughfall and stemflow: Observations from a deciduous forest and
a red pine plantation in the midwestern U.S.A.
Pryor S.C. and Barthelmie R.J. Water, Air, and Soil Pollution
2005 163/1-4 (203-227)
Wet deposition (WD), throughfall (TF) and stemflow (SF) measurements undertaken in a deciduous forest show 85% of the
WD liquid flux is observed as TF and approximately 2% as
SF. TF and SF were observed to be enriched in base cations
and accordingly had an average pH of 6.1 and 5.9, respectively
relative to a WD pH of 5.1. The seasonal variability of TF pH
below the deciduous canopies was more pronounced than that
of WD though both exhibited a growing season maximum, and
there is evidence that the seasonal variability of TF pH below the
pines is inverted relative to the deciduous canopies likely due to
enhanced dust capture and buffering by calcium carbonate. TF
ion concentrations differed significantly between deciduous and
pine canopies during the growing season, and there is some evidence that variation in sky view factor of 0.18-0.22 is sufficient
to manifest statistically differing TF composition below sugar
maples. The total atmospheric flux of inorganic nitrogen to the
forest is approximately 14-18 kg-N ha-1 yr-1 with approximately
half taken up by the canopy. Associated experiments designed
to quantify uncertainties in the nutrient fluxes included laboratory tests of the Aerochem automated wet-dry sampler. These
experiments indicate the delay in initiating sample collection is
less than half a minute for rainfall rates above 1 cm h-1 , but may
increase substantially for lower precipitation rates. В© Springer
2005.
1914 Rainfall interception model of forest canopy: A preliminary study (Chinese)
Guo M., Yu P., Wang Y. et al. Chinese Journal of Applied Ecology
2005 16/9 (1633-1637)
Canopy interception is an important hydrological process in forest ecosystem, and its modelling is of significance to understand
and estimate the rainfall interception by the canopy. In this paper,
a canopy rainfall interception model was established by dividing
a rain incident into a set of short period, calculating the rainfall
distribution intercepted by the canopy, and educing the process
of the rain incident. This model considered the effects of the
dryness of canopy and trunk on the evaporation from wet canopy
and trunk during one rain incident, and introduced two factors,
leaf area index (LAI) and surface area of trunk per unit area of
ground (SAI), when computing the evaporation. The application
of the model to simulate the rainfall interception process in a
Larix principis-rupprechtii plantation in Guyuan, south Ningxia
Hui autonomous region of China showed that the simulated and
measured throughfall were identical, and the absolute deviation
between simulated and measured results was within 1 mm.
But, when the precipitation was smaller than 6 mm, the simulated throughfall was lower than the measured one. The values
of simulated stemflow were lower than the measured values, and
the relative deviation between simulated and measured values
was smaller when the precipitation was larger. The process of
365
throughfall in the forest was also simulated, with the results fitted
well to the measured one.
Evaporation and transpiration
1915 Evaporation and land surface energy budget at the
Salar de Atacama, Northern Chile
Kampf S.K., Tyler S.W., Ortiz C.A. et al. Journal of Hydrology
2005 310/1-4 (236-252)
Playa systems are driven by evaporation processes, yet the mechanisms by which evaporation occurs through playa salt crusts are
still poorly understood. In this study we examine playa evaporation as it relates to land surface energy fluxes, salt crust characteristics, groundwater and climate at the Salar de Atacama, a 3000
km2 playa in northern Chile containing a uniquely broad range of
salt crust types. Land surface energy budget measurements were
taken at eight representative sites on this playa during winter
(August 2001) and summer (January 2002) seasons. Measured
values of net all-wave radiation were highest at vegetated and
rough halite crust sites and lowest over smooth, highly reflective
salt crusts. Over most of the Salar de Atacama, net radiation was
dissipated by means of soil and sensible heat fluxes. Dry salt
crusts tended to heat and cool very quickly, whereas soil heating
and cooling occurred more gradually at wetter vegetated sites.
Sensible heating was strongly linked to wind patterns, with highest sensible heat fluxes occurring on summer days with strong
afternoon winds. Very little energy available at the land surface
was used to evaporate water. Eddy covariance measurements
could only constrain evaporation rates to within 0.1 mm d-1 , and
some measured evaporation rates were less than this margin of
uncertainty. Evaporation rates ranged from 0.1 to 1.1 mm d-1 in
smooth salt crusts around the margin of the salar and from 0.4
to 2.8 mm d-1 in vegetated areas. No evaporation was detected
from the rugged halite salt crust that covers the interior of the
salar, though the depth to groundwater is less than 1 m in this
area. These crusts therefore represent a previously unrecorded
end member condition in which the salt crusts form a practically
impermeable barrier to evaporation. В© 2005 Elsevier B.V. All
rights reserved.
1916 Effects of vapor-pressure deficit and net-irradiance
calculation methods on accuracy of standardized PenmanMonteith equation in a Humid climate
Yoder R.E., Odhiambo L.O. and Wright W.C. Journal of Irrigation and Drainage Engineering 2005 131/3 (228-237)
The effects of some common vapor pressure deficit (VPD) and
net irradiance (Rn ) calculation methods on the accuracy of ETo
values estimated by using the standardized ASCE Penman-Monteith (ASCE-PM) equation for short grass were examined by
comparing the estimated ETo values with measured ETo , values
in a humid climate. Sensitivity analysis showed 17% and 84%
change in the estimated daily ETo values per unit change in the
calculated VPD and Rn values, respectively. A total of 12 VPD
and 27 Rn calculation methods were examined. Analyses of
variance indicated lack of equality in the means of estimated ETo
values obtained by different VPD and Rn methods. The percent
mean error in the estimated ETo values ranged from -0.9 to -8.4%
for VPD methods and from -0.3 to -19.7% for Rn methods. On
the basis of the coefficient of determination (r2 ) and the standard
error of the estimated (Sy/x ) values, the VPD calculated from saturation vapor pressure (es ), estimated by averaging the es at the
maximum and minimum daily air temperatures, and actual vapor
pressure (ea ), estimated by using either the average of minimum
and maximum relative humidity or the dew-point temperature,
gave more accurate results. Net irradiance (Rn ) estimated by
using a regression of relative short-wave solar irradiance, as well
as a linear regression on the square root of ea , resulted in relatively
more accurate estimates of ETo , than that obtained by methods
based on ea or clear-sky data alone. These results indicate that
in a humid climate, some of the VPD and Rn methods have a
significant effect on the accuracy of the ETo estimated by using
the standardized ASCE-PM equation. Journal of Irrigation and
Drainage Engineering В© ASCE.
366
HYDROLOGY
1917 Sensitivity of the food and agriculture organization
Penman-Monteith evapotranspiration estimates to alternative procedures for estimation of parameters
Nandagiri L. and Kovoor G.M. Journal of Irrigation and
Drainage Engineering 2005 131/3 (238-248)
Reference crop evapotranspiration (ETo ) is a key variable in procedures established for estimating evapotranspiration rates of
agriculture crops. As per internationally accepted procedures
outlined in the United Nations Food and Agriculture OrganizationвЂ™s Irrigation and Drainage Paper No. 56 (FAO-56), using
the Penman-Monteith (PM) combination equation is the recommended approach to computing ETo from ground-based climatological observations. Applying of the PM equation requires
converting input climate and site data into a number of parameters, and FAO-56 recommends exact procedures for estimating
these parameters. However, a plethora of alternative procedures
for estimating parameters exist in literature. As a consequence, it
is likely that ambiguous results may be obtained from the FAO-56
PM equation because of the adoption of such alternative (nonrecommended) supporting equations. The purpose of the present
study is to evaluate differences that could arise in FAO-56 ETo
estimates if nonrecommended equations are used to compute the
parameters. Using historical climate records from 1973 to 1992
of a station located in the humid tropical region of Karnataka
State, India, monthly ETo , estimates computed by FAO-56 recommended procedures were statistically compared with those
obtained by introducing alternative procedures for estimating
parameters. In all, 13 alternative algorithms for ETo estimation
were formulated, involving modified procedures for parameters
associated with weighting factors, net radiation, and vapor-pressure-deficit terms of the PM equation. For the 240-month period
considered, nine of these algorithms yielded ETo estimates that
were in close correspondence with FAO-56 estimates as indicated
by mean absolute relative difference (AMEAN) values within 1%
and maximum absolute relative difference (MAXE) values within
2%. The remaining four algorithms, involving nonrecommended
procedures for the vapor-pressure-deficit and net-radiation parameters, yielded considerably different ETo estimates, giving
rise to AMEAN values in the range of 2 to 8% and MAXE values
ranging between 8 and 28%. The results of this study highlight
the need for strict adherence to recommended procedures, especially for estimating of vapor-pressure-deficit and net-radiation
parameters if consistent results are to be obtained by the FAO56 approach. Journal of Irrigation and Drainage Engineering В©
ASCE.
1918 Simplified estimation of reference evapotranspiration
from pan evaporation data in California
Snyder R.L., Orang M., Matyac S. and Grismer M.E. Journal of
Irrigation and Drainage Engineering 2005 131/3 (249-253)
Evaporation pan (Ep ) data are often used to estimate reference
evapotranspiration (ETo ) for use in water resource planning and
irrigation scheduling. This paper reviews equations to estimate
ETo from Ep and provides a simpler method to make this conversion for arid climatic conditions like in California. The new
method accounts for fetch differences by first adjusting the EP
rates to values expected for 100 m of grass fetch. Then it relies
on an empirical relationship between ETo and the adjusted Ep
to determine Kp values; thus, eliminating the need for relative
humidity and wind speed data that are often unavailable. The
method is conceptually simpler, easier to code into computer
applications, and within California, it gave better results than
methods based on relative humidity and wind speed. However,
the method might require calibration in more humid or windier climates. Journal of Irrigation and Drainage Engineering В©
ASCE.
1919 Data reconciliation on the complex hydraulic system
of Canal de Provence
Deltour J.- L., Canivet E., Sanfilippo F. and Sau J. Journal of
Irrigation and Drainage Engineering 2005 131/3 (291-297)
A data reconciliation module, based on the measurements from
the hydraulic network, has been recently developed and implemented in the supervisory system of the SociВґetВґe du Canal de
Provence (SCP). The software has initially been used daily to
check the measured flow on the main canal. The data reconciliation occurs just after the measurement process. The measurement
network on the hydraulic system includes many sensors subject
to failure or deviation and is spread over a huge area. In addition,
discharge and volume measurements in open-channel hydraulic
networks are characterized by large uncertainties. The objective
of the data reconciliation is to take advantage of information
redundancy on a system to make a cross-check of real-time
measurements. By using this information redundancy, a data
reconciliation module allows detection of inconsistent measurements and measurement deviations and provides corrected values
whether the initial measurements are valid, biased, or invalid. A
derived consequence is better scheduling of the maintenance of
sensors. The results are corrected values for measured variables
and proposed values for nonmeasured quantities. A statistical
analysis of the results is performed. This analysis allows evaluation of the uncertainties attached to the estimated flows and
volume values. It allows also detecting invalid measurements
and drift of sensors and making decisions about which maintenance operations to perform. Journal of Irrigation and Drainage
Engineering В© ASCE.
1920 An approach to estimating evapotranspiration in the
Urumqi River basin, Tianshan, China, by means of remote
sensing and a geographical information system technique
Zhang W., Chen J., Ogawa K. and Yamaguchi Y. Hydrological
Processes 2005 19/9 (1839-1854)
An approach that makes use of meteorological measurements
and the spatial perspective provided by satellite data to estimate
the time series (monthly or daily) of evapotranspiration (ET) over
heterogeneous terrain two-dimensionally has been developed and
tested in the Urumqi River basin, Tianshan, China. The formulae utilized in the estimation of actual ET are based on KojimaвЂ™s
equation for a glacier/snow-covered area and MortonвЂ™s complementary relationship for the other land-cover classes. Data integration and image processing for the estimated ET were all executed on a raster image file that combines Landsat TM (red and
NIR reflectance data), land-cover classification and digital elevation model (DEM) in association with the use of meteorological
data under a geographic information system (GIS) environment.
The specific type of model (either KojimaвЂ™s or MortonвЂ™s) and
the extent to which it should be applied are determined jointly
by the land-cover categories and an algorithm describing the
seasonal land-cover changes. The spatially distributed meteorological parameters driving the model were either interpolated
from the routine observations with PRISM in the sparse network
of meteorological stations or calculated by the relationships of
these parameters with those routinely observed. Ground-surface
albedo data were derived by two approaches. For the season
when the TM scene was acquired it was obtained by weighting
the Landsat TM red and NIR reflectance data. For the other seasons, when the TM scene is not available, it was approximated by
multiplying the empirical parameters in regard to each land-cover
category with the albedo map of the season when the TM scene
was available. As a result, time series of ET can be obtained
not only quantitatively, but also visually as a two-dimensional
image map. The approach proposed was applied to the Urumqi
River basin, China. With field lysimeter data and estimates by
the water balance method and the converted results from pan
measurements as standard, a method validation was conducted
and the accuracy of ET estimation by the approach was evaluated.
Copyright В© 2005 John Wiley & Sons, Ltd.
1921 Evapotranspiration from a riparian fen wetland
Andersen H.E., Hansen S. and Jensen H.E. Nordic Hydrology
2005 36/2 (121-135)
Evapotranspiration rates were measured in a riparian fen wetland
dominated by vascular vegetation and surrounded by open agricultural areas and forests. The wetland is situated on a floodplain
in central Denmark. Measurements were taken throughout the
growing season (April-September) of 1999. Evapotranspiration
rates were higher than th ose published for other wetland types,
with an average of 3.6 mm d-1 during the growing season and a
peak rate of 5.6 mm d-1 . Daily average evapotranspiration was
110% of PenmanвЂ™s potential open water evaporation. Evatranspiration was the dominant sink in the energy balance of the
wetland studied. During the day, evapotranspiration accounted
for 82% of the available radiant energy, Rn . Due to the presence
of deposited fine-grained sediments, soil-water availability was
HYDROLOGY
kept high at all times which resulted in moderate canopy resistances, rc . (overall mean = 32 sm-1 ). Evapotranspiration was
controlled by a combination of driving forces: Rm saturation
vapour pressure deficit, D, and rc . It is hypothesized that the
results presented in this study are conditioned by the proximity of the wetland to drier upland areas. During periods with
high evaporative demand and low precipitation, warm, dry air
is formed over the upland areas and wetland evapotranspiration
rates are enhanced by local advection. Indicative evidence for
the hypothesis is presented. Although the absolute magnitude
of the results reported is only directly relevant to similar sites in
Denmark, the processes and controls described are considered
to be representative of riparian wetlands subjected to frequent
flooding and/or with a high groundwater table, with vascular
vegetation, and which are narrow corridors in open agricultural
landscapes. В© IWA Publishing 2005.
1922 Dynamics of transpiration and evaporation following
a moisture pulse in semiarid grassland: A chamber-based
isotope method for partitioning flux components
Yepez E.A., Huxman T.E., Ignace D.D. et al. Agricultural and
Forest Meteorology 2005 132/3-4 (359-376)
We describe a novel method for partitioning evapotranspiration
(ET) from isotopic measurements of water vapor within large
(4.86 m3 ) plot-scale gas exchange chambers. Using this approach, the short-term (15-day) dynamics of transpiration (T)
and evaporation (E) in experimental replicated stands of the invasive grass Eragrostis lehmanniana and the native Heteropogon
contortus were assessed following a 39-mm irrigation event in
semiarid grassland in southeastern Arizona, USA. Water vapor
samples (20-40 L each) were collected sequentially during a 6min transient increase of vapor concentration inside the chambers
and used to produce Keeling plots (isotope mixing relationships)
for identification of the isotopic composition of ET and partitioning of component fluxes. The method worked well in plots
free of grass cover and in the sparsely covered plots of E. lehmanniana. Keeling plot estimates of the isotopic composition
of soil evaporation ( E ) in bare plots closely matched modeled
values, lending strong support for the validity of the chamber
approach. T/ET increased in stands of E. lehmanniana from 0.35
0.07 on day 1 to 0.43
0.08 on day 3 after the irrigation
pulse, but decreased to 0.22 0.05 by day 7 as the soil surface
dried. Estimates of stand transpiration from the Keeling plot
chamber method were positively correlated (PearsonвЂ™s r = 0.76,
p = 0.0004, n = 17) with independent estimates based on leafto-canopy scaling of stomatal conductance. We were unable to
calculate T/ET on days 1 and 3 in plots of H. contortus because
Keeling plot intercepts did not fall within the range of soil and
canopy end-member isotope values. This likely occurred due to
unaccounted effects of a wet litter layer on the estimation of E .
Our approach is useful for partitioning ET over a dynamic wetting
event in semi-arid grassland at a scale relevant for experimental
ecosystem studies, but requires further validation under a wide
range of vegetation structures and environmental conditions. В©
2005 Elsevier B.V. All rights reserved.
1923 Comparative analysis of the actual evapotranspiration
of Flemish forest and cropland, using the soil water balance
model WAVE
Verstraeten W.W., Muys B., Feyen J. et al. Hydrology and Earth
System Sciences 2005 9/3 (225-241)
This paper focuses on the quantification of the green - vegetation
related - water flux of forest stands in the temperate lowland of
Flanders. The underlying reason of the research was to develop
a methodology for assessing the impact of forests on the hydrologic cycle in comparison to agriculture. The tested approach
for calculating the water use by forests was based on the application of the soil water balance model WAVE. The study involved
the collection of data from 14 forest stands, the calibration and
validation of the WAVE model, and the comparison of the water use (WU) components - transpiration, soil and interception
evaporation - between forest and cropland. For model calib
ration purposes simulated and measured time series of soil water
content at different soil depths, period March 2000-August 2001,
were compared. A multiplesite validation was conducted as well.
Actual tree transpiration calculated with sap flow measurements
in three forest stands gave similar results for two of the three
367
stands of pine (Pinus sylvestris L.), but WAVE overestimated
the actual measured transpiration for a stand of poplar (Populus
sp.). A useful approach to compare the WU components of
forest versus cropland is scenario analysis based on the validated
WAVE model. The statistical Profile Analysis method was implemented to explore and analyse the simulated WU time series.
With an average annual rainfall of 819 mm, the results reveal that
forests in Flanders consume more water than agricultural crops.
A 30 years average of 491 mm for 10 forests stands versus 398
mm for 10 cropped agricultural fields was derived. The WU
components, on yearly basis, also differ between the two land
use types (transpiration: 315 mm for forest and 261 mm for
agricultural land use; soil evaporation: 47 mm and 131 mm, for
forest and cropland, respectively). Forest canopy interception
evaporation was estimated at 126 mm, while it was negligible
for cropland. В© 2005 Author(s). This work is licensed under a
Creative Commons License.
1924 Evapotranspiration of natural Quercus liaotungensis
and Tilia paucicostata secondary stands in Liupan Mountains
of Ningxia (Chinese)
Xiong W., Wang Y., Yu P. et al. Chinese Journal of Applied
Ecology 2005 16/9 (1628-1632)
With heat dissipation probe technique and combined with microlysimeter and hydrological methods, this paper studied the
evapotranspiration of secondary Quercus liaotungensis and Tilia
paucicostata stands, and its relationship to forest structure from
August to September 2004. The results indicated that the stem
sap flux density (SFD) Of Quercus liaotungensis and Tilia paucicostata changed regularly from day to night in later growth season. In relatively still period (nighttime), the SFD kept low
values continuously, usually below 0.05 l cm-2 min-1 , while in
active period (daytime), it increased quickly, usually below 0.25
l cm-2 . min-1 . The daily transpiration of whole-tree was estimated based on the calculation of daily cumulative SFD, which
showed that there existed a significant difference between two
tree species. The daily transpiration of Quercus liaotungensis
reached 5.31 and 2.48 L d-1 in sunny- and cloudy-days, 2.35 and
3.75 folds as that of Tilia paucicostata, respectively. There was
no significant difference in daily leaf transpiration rate between
these two shrub species. During measurement periods, the average daily stand evapotranspiration was 1.45 mm d-1 , including
transpiration (0.72 mm d-1 ), soil evaporation (0.19 mm d-1 ), and
canopy interception (0.54 mm d-1 ), which accounted for 49.6%,
13.3% and 37.1% of the total evapotranspiration, respectively.
The results showed that the difference of whole-tree transpiration
between tree species contributed significantly to the difference of
tree canopy transpiration, while the difference of shrub canopy
transpiration was on account of the leaf amount in the canopy.
The effects of vertical layers in the stand on total stand evapotranspiration also differed, with a percentage of 65.8%, 20.9%
and 13.3% for tree canopy, shrub canopy and floor, respectively,
which meant that the transpiration and interception of tree canopy
contributed most to the total evpotranspiration, followed by shrub
transpiration, soil evaporation, and grass transpiration.
Runoff, streamflow and basins
1925 A method for evaluating the accuracy of quantitative precipitation estimates from a hydrologic modeling
perspective
Gourley J.J. and Vieux B.E. Journal of Hydrometeorology 2005
6/2 (115-133)
A major goal in quantitative precipitation estimation and forecasting is the ability to provide accurate initial conditions for the
purposes of hydrologic modeling. The accuracy of a streamflow prediction system is dependent upon how well the initial
hydrometeorological states are characterized. A methodology
is developed to objectively and quantitatively evaluate the skill
of several different precipitation algorithms at the scale of application-a watershed. Thousands of hydrologic simulations are
performed in an ensemble fashion, enabling an exploration of the
model parameter space. Probabilistic statistics are then utilized
to compare the relative skill of hydrologic simulations produced
368
HYDROLOGY
from the different precipitation inputs to the observed streamflow.
The primary focus of this study is to demonstrate a methodology
to evaluate precipitation algorithms that can be used to supplement traditional radar-rain gauge analyses. This approach is
appropriate for the evaluation of precipitation estimates or forecasts that are intended to serve as inputs to hydrologic models.
В© 2005 American Meteorological Society.
1926 A recent increase in western U.S. Streamflow variability and persistence
Pagano T. and Garen D. Journal of Hydrometeorology 2005 6/2
(173-179)
April-September streamflow volume data from 141 unregulated
basins in the western United States were analyzed for trends
in year-to-year variability and persistence. Decadal time-scale
changes in streamflow variability and lag-1-yr autocorrelation
(persistence) were observed. The significance of the variability
trends was tested using a jackknife procedure involving the random resampling of seasonal flows from the historical record. The
1930s-50s was a period of low variability and high persistence,
the 1950s-70s was a period of low variability and antipersistence, and the period after 1980 was highly variable and highly
persistent. In particular, regions from California and Nevada to
southern Idaho, Utah, and Colorado have recently experienced
an unprecedented sequence of consecutive wet years along with
multiyear extreme droughts.
1927 Comparative analysis of glacial and nival streamflow
regimes with implications for lotic habitat quantity and fish
species richness
Fleming S.W. River Research and Applications 2005 21/4 (363379)
Growing interest in the differential responses of glacial and nival rivers to climatic forcing, and in ecological distinctions between the two streamflow regimes, suggests the need for a better
comparative understanding of how the annual hydrologic cycle
differs with presence or absence of catchment glacial cover. In
this study, timing and magnitude characteristics of the average
annual hydrographs of five glacierized and four nival catchments
in the southwestern Canadian subarctic are empirically identified
and compared. Likely effects upon fish habitat are qualitatively
assessed, and net fisheries potential is tentatively investigated
using taxa richness data. The chief hydrological conclusions
at P < 0.05 using Kolmogorov-Smirnov and empirical orthogonal function analyses are: (1) catchment glacial cover results
in freshets that are longer, larger, and peak later than those
experienced by the nival regime; (2) the winter baseflows of
glacial rivers are also much higher on a unit-catchment-area basis; and (3) basin scale and degree of catchment glacial cover
are of comparable importance in determining the magnitude of
the annual hydrologic cycle. These differences arise from the
greater availability, both in volume and over time, of meltwater
in glacial catchments, which in part reflects the consistently negative alpine glacial mass balances observed both in the present
study area and globally under historical climatic warming. Such
regime distinctions result in increased spawning season and winter aquatic habitat availability, which may in turn offset negative habitat characteristics previously identified for glacial river
ecosystems. While previous studies have suggested that glacial influences tend to decrease macroinvertebrate diversity and
increase salmon populations, preliminary analysis of available
fish species presence/absence data from the current study area
tentatively appears to suggest similar or, perhaps, slightly higher
fish taxa richness relative to nival streams; in all three cases,
however, catchment lake cover may play a key hydroecological
modifying role. The results strongly confirm and extend existing
understanding of glacial-nival regime differences with respect to
both streamflow and fisheries ecology, and raise new questions
for future research. Copyright В© 2005 John Wiley & Sons, Ltd.
1928 Assessing the effectiveness of enhancement activities
in urban streams: I. Habitat responses
Suren A.M., Riis T., Biggs B.J.F. et al. River Research and
Applications 2005 21/4 (381-401)
Effects of stream enhancement on habitat conditions in five
spring-fed urban streams in Christchurch, New Zealand, were investigated. Stream enhancement consisted of riparian planting at
three sites, and riparian planting and channel modifications at two
sites, where a concrete dish channel and a timber-lined channel
were removed, and natural banks reinstated. Sites were surveyed
prior to enhancement activities and 5 years after, and changes in
riparian conditions (composition, horizontal and vertical cover),
instream conditions (bank modifications, inorganic and organic
material on the streambed), and hydraulic conditions (wetted
perimeter, cross-sectional area, depths and velocities) quantified.
Enhanced sites generally had higher marginal vegetation cover,
as well as increased overhanging riparian vegetation, reflecting
planting of Carex sedges close to the water. Bed sediments
changed at some sites, with the greatest change being replacement of a concrete channel with gravel and cobble substrate. Bryophyte cover declined at this site, reflecting loss of stable habitat
where these plants grew. Bed sediments changed less at other
sites, and cover of fine sediments increased in some enhanced
sites, presumably from sediment runoff from nearby residential
development. Filamentous algal cover decreased at one stream
where shade increased, but increased in another stream where
the removal of timber-lined banks and creation of a large pond
decreased shade. Stream enhancement increased variability in
velocity at three of the five sites, but overall changes to stream hydraulics were small. Although enhancement activities altered the
physical conditions of the streams, major changes occurred only
to riparian vegetation and bank conditions. Lack of other major
changes to instream physical conditions most likely reflected the
limited range of channel morphology alterations under-taken.
Moreover, the flat topography of Christchurch and naturally low
stream discharge further constrained changes to instream physical conditions from enhancement activities. Sediment inputs
from continuing urban development also negated the effects of
adding coarse substrates. These over-arching factors may constrain the success of future stream enhancement projects within
Christchurch. Copyright В© 2005 John Wiley & Sons, Ltd.
1929 Assessing the effectiveness of enhancement activities
in urban streams: II. Responses of invertebrate communities
Suren A.M. and McMurtrie S. River Research and Applications
2005 21/4 (439-453)
The effects of habitat enhancement on the invertebrate communities in five urban streams in Christchurch, New Zealand, were
investigated. All streams underwent riparian planting, while extensive channel modifications were made at two streams, where
a concrete dish channel and a wooden timber-lined stream were
removed and natural banks reinstated. Benthic invertebrates were
collected before enhancement and 5 years after from the same
locations. Invertebrates were also collected from control sites in
each stream in 2001. Desired goals of enhancement activities
included increasing the densities of mayflies and caddisflies,
and decreasing densities of oligochaetes, snails and midges.
Enhancement activities changed riparian vegetation and bank
conditions, as well as substrate composition, instream organic
matter and variability of instream velocities. Invertebrate communities prior to enhancement were typical of those in urban
environments, and dominated by snails (Potamopyrgus, Physa),
the amphipod Paracalliope, the hydroptilid caddisfly Oxyethira,
oligochaetes and chironomids. Stream enhancement caused only
small changes to the invertebrate community, with subtle shifts
in overall abundance, species evenness, diversity, and ordination
scores. Lack of a consistent strong response by invertebrates to
enhancement activities, and continued absence of caddisflies and
mayflies from enhanced sites may reflect lack of sufficient change
to instream conditions as a result of stream enhancement, colonization bottlenecks for aerial stages of these animals, and the
inability of individuals outside the urban watershed to perceive
these enhanced вЂ�islandsвЂ™ of good habitat. Alternatively, contamination of streambed sediments, excess sedimentation and reduced
base flows may be limiting factors precluding successful invertebrate colonization in enhanced sites. These results highlight
the importance of setting clear goals and objectives necessary
to meet these goals. Enhancement of riparian zones in urban
streams may not be adequate to improve benthic invertebrate
communities. Identifying over-arching factors that potentially
limit invertebrate communities will enable the enhancement potential of streams to be better assesed, and allow managers to
identify sites where recovery of biological communities is pos-
HYDROLOGY
sible, and where such recovery is not. Copyright В© 2005 John
Wiley & Sons, Ltd.
1930 Changes toward earlier streamflow timing across western North America
Stewart I.T., Cayan D.R. and Dettinger M.D. Journal of Climate
2005 18/8 (1136-1155)
The highly variable timing of streamflow in snowmelt-dominated
basins across western North America is an important consequence, and indicator, of climate fluctuations. Changes in the
timing of snowmelt-derived streamflow from 1948 to 2002 were
investigated in a network of 302 western North America gauges
by examining the center of mass for flow, spring pulse onset
dates, and seasonal fractional flows through trend and principal
component analyses. Statistical analysis of the streamflow timing
measures with Pacific climate indicators identified local and key
large-scale processes that govern the regionally coherent parts
of the changes and their relative importance. Widespread and
regionally coherent trends toward earlier onsets of springtime
snowmelt and streamflow have taken place across most of western North America, affecting an area that is much larger than
previously recognized. These timing changes have resulted in
increasing fractions of annual flow occurring earlier in the water
year by 1-4 weeks. The immediate (or proximal) forcings for
the spatially coherent parts of the year-to-year fluctuations and
longer-term trends of streamflow timing have been higher winter
and spring temperatures. Although these temperature changes
are partly controlled by the decadal-scale Pacific climate mode
[Pacific decadal oscillation (PDO)], a separate and significant
part of the variance is associated with a springtime warming trend
that spans the PDO phases. В© 2005 American Meteorological
Society.
1931 The relationship between potentially erosive storm energy and daily rainfall quantity in England and Wales
Davison P., Hutchins M.G., Anthony S.G. et al. Science of the
Total Environment 2005 344/1-3 SPEC. ISS. (15-25)
Erosive storm energy is the primary driver of soil detachment,
and hence a major determinant of transfer of sediment and particulate phosphorus (P) to surface waters. Modelling of sediment
and P loss at catchment scale, for example for the development of
catchment and national mitigation policies, requires a spatially
interpolated estimate of variation in erosion risk. To this end we
present a method of estimating total rainfall erosivity, as kinetic
energy (KE), for any location in England and Wales, from daily
rainfall data or monthly climate data. Analysis of detailed, highresolution records from eleven contrasting sites showed strong
predictive correlations between daily rainfall quantity and associated daily total kinetic energy estimated from hourly rainfall intensities. The coefficients showed systematic seasonal variation,
with greatest KE per unit of rainfall in late summer and autumn
months. In contrast, no systematic spatial variation was found as
a function of location or continentality index. The relationships
were integrated with probability distributions of rainfall quantity
per rain day derived from spatial climate data (monthly rainfall
totals and numbers of rain days). The resulting map captures and
quantifies the effects of rainfall quantity and intensity patterns on
risk of sediment detachment, and as such provides a critical input
layer to catchment-scale models of sediment and P transfer. В©
2005 Elsevier B.V. All rights reserved.
1932 Temporal analysis of the frequency and duration of low
and high streamflow: Years of record needed to characterize
streamflow variability
Huh S., Dickey D.A., Meador M.R. and Ruhl K.E. Journal of
Hydrology 2005 310/1-4 (78-94)
A temporal analysis of the number and duration of exceedences
of high- and low-flow thresholds was conducted to determine the
number of years required to detect a level shift using data from
Virginia, North Carolina, and South Carolina. Two methods were
used - ordinary least squares assuming a known error variance and
generalized least squares without a known error variance. Using
ordinary least squares, the mean number of years required to detect a one standard deviation level shift in measures of low-flow
variability was 57.2 (28.6 on either side of the break), compared
to 40.0 years for measures of high-flow variability. These means
become 57.6 and 41.6 when generalized least squares is used.
369
No significant relations between years and elevation or drainage
area were detected (P>0.05). Cluster analysis did not suggest
geographic patterns in years related to physiography or major
hydrologic regions. Referring to the number of observations required to detect a one standard deviation shift as вЂ�characterizingвЂ™
the variability, it appears that at least 20 years of record on either
side of a shift may be necessary to adequately characterize highflow variability. A longer streamflow record (about 30 years on
either side) may be required to characterize low-flow variability.
В© 2005 Elsevier B.V. All rights reserved.
1933 Sensitivity analyses of a distributed catchment model
to verify the model structure
Sieber A. and Uhlenbrook S. Journal of Hydrology 2005 310/1-4
(216-235)
Sensitivity analyses are valuable tools for identifying important
model parameters, testing the model conceptualization, and improving the model structure. They help to apply the model
efficiently and to enable a focussed planning of future research
and field measurement. Two different methods were used for
sensitivity analyses of the complex process-oriented model TAC
D (tracer aided catchment model, distributed) that was applied
to the meso-scale Brugga basin (40 km2 ) and the sub-basin St
Wilhelmer Talbach (15.2 km2 ). Five simulations periods were
investigated: two summer events, two snow melt induced events
and one summer low flow period. The model was applied using
400 different parameter sets, which were generated by Monte
Carlo simulations using latin hypercube sampling. The regional
sensitivity analysis (RSA) allowed determining the most significant parameters for the complete simulation periods using a
graphical method. The results of the regression-based sensitivity
analysis were more detailed and complex. The temporal variability of the simulation sensitivity could be observed continuously
and the significance of the parameters could be determined in
a quantitative way. A dependency of the simulation sensitivity
on initial- and boundary conditions and the temporal and spatial variability of the sensitivity to some model parameters was
revealed by the regression-based sensitivity analysis. Thus, the
difficulty of transferring the results to different time periods or
model applications in other catchments became obvious. The
analysis of the temporal course of the simulation sensitivity to
parameter values in conjunction with simulated and measured additional data sets (precipitation, temperature, reservoir volumes
etc.) gave further insight into the internal model behaviour and
demonstrated the plausibility of the model structure and process
conceptionalizations. В© 2005 Elsevier B.V. All rights reserved.
1934 Characterisation of streamflow regimes in central
Spain, based on relevant hydrobiological parameters
Sanz D.B. and Del JalВґon D.G. Journal of Hydrology 2005 310/1-4
(266-279)
The biotic composition, structure, and function of aquatic, wetland, and riparian ecosystem depend largely on the hydrological
regime (Poff, N.L., Ward, J.V., 1990. Implications of streamflow variability and predictability for lotic community structure:
a regional analysis of streamflow patterns. Can. J. Fisheries
Aquat. Sci. 46, 1805-1818; Richter, B.D., Baumgartner, J.V.,
Wiginton, R., Braun, D.P., 1997 How much water does a river
need? Freshwater Biol. 37, 231-249). Available flow data for
many rivers in the world can be used to validate these ecological
theories. There is a demand for studies that use hydrological indices to establish criteria, which serve to group together regime
types at a local level. Once this has been done, these hydrologically similar groups can be used to identify communities
of living organisms that are linked to specific aspects of the
riverвЂ™s behaviour. An approach to characterise flow regimes in
the river network of the Tagus basin in Spain is presented. The
river Tagus (ro Tajo) is one of the seven major rivers of the
Iberian peninsula. All hydrological data were acquired from the
measurements made in the Tagus basin, at 25 gauging stations.
Twelve variables were derived for each gauged site to describe
variability and predictability of average streamflow conditions,
and to describe the frequency, timing and intensity of high flow
and low flow extremes. A hierarchical clustering routine was
used to identify similar groups of rivers as defined in terms of
similar characteristics of their streamflow regime. The variables
370
HYDROLOGY
were also examined with simple correlations to determine if multicollinearity occurred, in order to reject redundant parameters or
to identify similar behaviour trends between pairs of parameters.
Some parameters have shown a tendency to increase or decrease
along the east-west axis, suggesting that some of the studied
characteristics may have a geographical cause. Cluster analysis,
with the values of the 12 parameters, reveals two main groups,
each of which splits into two main subdivisions. One of these
subgroups contains six rivers with similar characteristics, can be
considered to be вЂ�classic regular riversвЂ™, the stations in this first
subgroup are mostly situated geographically close to each other.
At the other end, we have found a subgroup, with a high variation
of flows over the year and high flood flows; these rivers are highly
irregular rivers with great changes. This regular-irregular gradient found between the groups is similar to that observed by others
authors (Poff, N.L., Allan J.D., 1995. Functional organization
of stream fish assemblages in relation to hydrological variability.
Ecology 76, 606-627), and strong associations have been documented with compositions of populations and probably reflect
differences in other similar important environmental factors. В©
2005 Elsevier B.V. All rights reserved.
1935 Consensus seasonal Flood Forecasts and Warning Response System (FFWRS): An alternate for nonstructural
flood management in Bangladesh
Chowdhury Md.R. Environmental Management 2005 35/6 (716725)
Despite advances in short-range flood forecasting and information dissemination systems in Bangladesh, the present system is
less than satisfactory. This is because of short lead-time products,
outdated dissemination networks, and lack of direct feedback
from the end-user. One viable solution is to produce long-lead
seasonal forecasts-the demand for which is significantly increasing in Bangladesh-and disseminate these products through the appropriate channels. As observed in other regions, the success of
seasonal forecasts, in contrast to short-term forecast, depends on
consensus among the participating institutions. The Flood Forecasting and Warning Response System (henceforth, FFWRS) has
been found to be an important component in a comprehensive and
participatory approach to seasonal flood management. A general
consensus in producing seasonal forecasts can thus be achieved
by enhancing the existing FFWRS. Therefore, the primary objective of this paper is to revisit and modify the framework of an
ideal warning response system for issuance of consensus seasonal
flood forecasts in Bangladesh. The five-stage FFWRS-i) Flood
forecasting, ii) Forecast interpretation and message formulation,
iii) Warning preparation and dissemination, iv) Responses, and
v) Review and analysis-has been modified. To apply the concept of consensus forecast, a framework similar to that of the
Southern African Regional Climate Outlook Forum (SARCOF)
has been discussed. Finally, the need for a climate Outlook
Fora has been emphasized for a comprehensive and participatory
approach to seasonal flood hazard management in Bangladesh.
В© 2005 Springer Science+Business Media, Inc.
1936 Statistical guidelines for curve number generation
Schneider L.E. and McCuen R.H. Journal of Irrigation and
Drainage Engineering 2005 131/3 (282-290)
The accuracy of runoff curve numbers (CNs) is unknown, and
empirical evidence has suggested that with the current CN table, hydrological systems are being over designed - which some
believe is due to a variable known as the initial abstraction coefficient ( ). Therefore, guidelines to produce a new CN table are
needed. In order to develop this set of guidelines, the following
objectives were met: Determination of CN and sensitivity,
assessment of the accuracy of alternative methods for determining CNs, examination of the effect of the range of data, and
evaluation of the potential change in hydrologic design due to a
new table. Using measured and simulated data, the methods of
estimating the CN were evaluated and assessed for accuracy. A
new method using concepts of lognormal frequency was developed and found to be more accurate than the current practices. It
was also found that is an insensitive variable when compared
to the CN, and therefore, may complicate the optimal fitting of
the CNs. Finally, it was determined that developing a new CN
table would affect the estimation of peak discharge rates, and
thus hydrologic designs. Therefore, it may be advantageous to
develop a new CN table based on peak discharge measurements
rather than depths of rainfall and runoff. Guidelines that should
lead to a revised CN model with improved accuracy are provided.
Journal of Irrigation and Drainage Engineering В© ASCE.
1937 Probability distribution type of Canadian annual minimum streamflow
Yue S. and Pilon P. Hydrological Sciences Journal 2005 50/3
(427-438)
The method of L-moment ratio diagrams along with the averaged
weighted distance (AWD) is applied to identify a probability
distribution of annual minimum streamflow, namely annual minimum daily streamflow in II climatic regions of Canada. Across
the entire country, the Pearson type III probability distribution
is an acceptable distribution for describing annual minimum
streamflow with the 3-parameter lognormal and log Pearson type
III distributions as potential candidates. Some minor differences
in the probability distribution type among different climatic regions are also observed, which may be taken into account in the
selection of the distribution type of annual minimum streamflow.
Copyright В© 2005 IAHS Press.
1938 Improving generalization of artificial neural networks
in rainfall-runoff modelling
Giustolisi O. and Laucelli D. Hydrological Sciences Journal 2005
50/3 (439-457)
Artificial neural networks (ANNs) are general-purpose techniques that can be used for nonlinear data-driven rainfall-runoff
modelling. The key issue to construct a good model by means of
ANNs is to understand their structural features and the problems
related to their construction. Indeed, the quantity and quality
of data, the type of noise and the mathematical properties of
the algorithm for estimating the usual large number of parameters (weights) are crucial for the generalization performances of
ANNs. However, it is well known that ANNs may suffer from
poor generalization properties due to the high number of parameters and non-Gaussian data noise. Therefore, in the first part
of this paper, the features and problems of ANNs are discussed.
Eight Avoiding Overfitting Techniques are then presented, considering that these are methods for improving the generalization
of ANNs. For this reason, they have been tested on two case
studies - rainfall-runoff data from two drainage basins in the
south of Italy - in order to gain insight into their propertics
and to investigate if there is one that absolutely gives the best
performance. Copyright В© 2005 IAHS Press.
1939 Variability in the discharge of South American rivers
and in climate
Gara N.O. and Mechoso C.R. Hydrological Sciences Journal
2005 50/3 (459-478)
Changes in trend and quasi-periodicities are sought in the time
series of river discharges in all major South American basins.
The relationship between trends and quasi-periodicities found
and climate variations on interannual and longer time scales are
discussed. Consideration of multiple rivers gives insight into the
geographical extent of hydrological signals and climate impacts.
It is found that the streamflow of all major rivers of South America
has experienced an increased trend since the early 1970s. It is
suggested that this simultaneity may reflect the impact of a largescale climate change. All the time series of river streamflows that
were analysed show El NiЛњno-like periodicities. Only for La Plata
Basin do these explain a larger part of the total variance than the
other quasi-periodicities. There are two other quasi-oscillations
in the time series analysed: one of them with a longer period
- around 17 years - and the other of about 9 years. Previous
work has related these oscillations to sea-surface temperature
anomalies in the Atlantic Ocean. Copyright В© 2005 IAHS Press.
1940 Trends in frequency of precipitation extremes in the
Yangtze River basin, China: 1960-2003
Su B., Xiao B., Zhu D. and Jiang T. Hydrological Sciences Journal 2005 50/3 (479-492)
The spatial distribution and trends in the frequency of precipitation extremes over the last 44 years (1960-2003), especially since
1990, have been analysed using daily precipitation data from
147 stations in the Yangtze River basin. The research results
HYDROLOGY
are as follows: (1) The 15 mm precipitation isohyet approximately divides the precipitation extremes (corresponding to the
95th percentile) of the stations in the middle and lower Yangtze
reaches (higher) from those of the upper Yangtze reaches (lower).
Also the starting time of the precipitation extremes in the middle
and lower Yangtze reaches is earlier than of those in the upper
Yangtze reaches. Precipitation extremes are concentrated mostly
in June in the middle and lower Yangtze reaches, and July in the
upper Yangtze reaches. (2) During the period 1960-2003, the
first two decades had fewer precipitation extremes than the last
two decades. There have been significant increasing trends and
step changes in frequency of annual total precipitation extremes
and precipitation extremes with a 1-5 day gap in the middle
and lower Yangtze reaches. Precipitation extremes occur more
frequently in shorter periods, separated by a few days. Precipitation extremes are also becoming more concentrated in the month
with the highest frequency of extremes (June) in the middle and
lower Yangtze reaches. In the upper Yangtze reaches, there is an
upward tendency of extreme events in June. Increasing precipitation extremes in June for both the middle and lower, and the
upper Yangtze reaches will increase the probability of flooding if
the observed trends of the last 40 years continue into the future.
Copyright В© 2005 IAHS Press.
1941 The use of digital elevation models in the identification
and characterization of catchments over different grid scales
Hancock G.R. Hydrological Processes 2005 19/9 (1727-1749)
This study examines the ability of well-known hydrological and
geomorphological descriptors and statistics to differentiate between catchments with spatially varying geology, size and shape
subject to the same climate in the Northern Territory, Australia.
The effect of digital elevation model grid resolution on these
statistics is also examined. Results demonstrate that catchment
descriptors such as the area-slope relationship, cumulative area
distribution and hypsometric curve can differentiate between
catchments with different geology and resultant morphology,
but catchment network statistics are insensitive to differences
in geology. Examination of the effects of digital elevation model
grid scale demonstrates that while considerable catchment information can be gained at digital elevation grids greater than
10 m by 10 m, hillslope and hydrological detail can be lost.
Geomorphic descriptors such as the area-slope relationship, cumulative area distribution, width function and Strahler statistics
were shown to be sensitive to digital elevation model grid scale,
but the hypsometric curve was not. Consequently, caution is
needed when deciding on an appropriate grid resolution as well
as the interpretation and analysis of catchment properties at grid
scales greater than that for optimal hillslope and area aggregation
definition. Copyright В© 2005 John Wiley & Sons, Ltd.
1942 Estimation of Columbia River virgin flow: 1879 to
1928
Naik P.K. and Jay D.A. Hydrological Processes 2005 19/9 (18071824)
The Columbia River is a major source of and conduit for Pacific
Northwest economic activity, and is one of the more heavily
modified rivers in North America. Understanding human and
climate-induced changes in its hydrologic properties is, therefore, vital. Long streamflow records are essential to determining
how runoff has changed over time, and Columbia River daily
streamflow record at The Dalles began in 1878. To understand
and separate anthropogenic and climate effects, however, it is
also necessary to have a basin-scale estimate of virgin or naturalized flow. The United States Geological Survey has calculated a
monthly averaged adjusted river flow at The Dalles for 1879-1999
that accounts for the effects of flow regulation. The Bonneville
Power Administration has estimated the monthly averaged virgin
flow at The Dalles, i.e. the flow in the absence of both flow regulation and irrigation depletion for 1929-89. We have estimated
the monthly virgin flow of the Columbia River at The Dalles from
records of irrigated area for the missing early years, i.e. for the
period 1879-1928. In addition, to allow hindcasting of a virgin
flow sediment transport for the system, a daily virgin flow index
with realistic higher moments and spectral properties has been
calculated. Examination of the virgin flow record shows that
climate change since the late 19th century has decreased annual
average flow volume by > 7%; irrigation depletion has reduced
371
the flow by another 7%. Copyright В© 2005 John Wiley & Sons,
Ltd.
1943 Sensitivity of soil moisture field evolution to rainfall
forcing
Yoo C., Kim S.- J. and Valdes J.B. Hydrological Processes 2005
19/9 (1855-1869)
In this paper the temporal behaviour of soil moisture is modelled
and statistically characterized by use of the zero-dimensional
model for soil moisture dynamics and the rectangular pulses Poisson process model for rain all forcing. The mean, covariance
and spectral density function of soil moisture (both instantaneous
and locally averaged cases) are analytically derived to evaluate its
sensitivity to the model parameters. Finally, the probability density function of soil moisture is derived to evaluate the effect of
rainfall forcing. All the model parameters used have been tuned
to the Monsoon вЂ�90 data. Results can be summarized as follows.
(1) Only the soil moisture model parameters ( and nZr ) are
found to affect the autocorrelation function in a distinguishable
manner. On the other hand, both the rainfall model parameter
( ) and the effective soil depth (nZr ) are found to be of impact
to the soil moisture spectrum. However, as the smoothing (or
damping) effect of soil is so dominant, about 20% variation of
one parameter seems not to affect significantly the second-order
statistics of soil moisture. (2) More difference can be found by
applying a longer averaging time, which is found to obviously
decrease the variance but increase the correlation even though
no overlapping between neighbouring soil moisture data was
allowed. (3) Among rainfall model parameters, the arrival rate
was found to be most important for the soil moisture evolution.
When increasing the arrival rate of rainfall, the histogram of soil
moisture shifts its peak to a certain value as well as becomes
more concentrated around the peak. However, by decreasing the
arrival rate of rainfall, a much smaller (almost to zero) mean value
of soil moisture was estimated, even though the total volume of
rainfall remained constant. This indicates that desertification
may take place without decreasing the total volume of rainfall.
Copyright В© 2005 John Wiley & Sons, Ltd.
1944 Characteristics of surface runoff and throughflow in
a purple soil of Southwestern China under various rainfall
events
Liu G., Tian G., Shu D. et al. Hydrological Processes 2005 19/9
(1883-1891)
In order to harvest runoff to palliate water disaster as well as
effectively manage irrigation and fertilizer application in the
studied region, it is necessary to better understand the runoff
processes. A newly designed runoff collection system for a plot
scale was used to partition runoff under contrasting rainfall events
into surface flow and subsurface flow to obtain characteristics of
surface runoff and throughflow in a purple soil (Regosols in
FAO taxonomy, Entisol in USDA taxonomy) of Sichuan, China.
Under small rainfall (shower and drizzle), only surface runoff
was observed. It is noted that, under shower, particularly with
antecedent dry soil conditions, the highest peak surface runoff
significantly lagged behind that of rainfall, because air-locked
soil pores of the top layer appeared temporally. Under rainstorm
and downpour, surface runoff and throughflow both commenced
and showed hysteresis. The hydrograph of surface runoff better
resembled that of rainfall than throughflow did. The durations
of throughflow discharge of post-rainfall-end were near the same
(within 24 h) under various rainfalls and rather dependent upon
the soil properties than the rainfall characteristics. Throughflow
is about 60-90% of total runoff, and especially significant in a
ploughed layer under downpour. The chloride concentration of
throughflow was over twice that of surface runoff and rainfall,
implying that throughflow contains more nutrients than surface
runoff. Presumably, surface runoff was primarily governed by
an infiltration-excess or saturated excess-infiltration mechanism
under unsaturated or saturated soil conditions. Therefore, the
management of water and fertilizer, and the harvesting of water
flow in the ploughed soil layer, should be emphasized in this
region. Copyright В© 2005 John Wiley & Sons, Ltd.
1945 Temporal variation of river flow renewability in the
middle Yellow River and the influencing factors
Xu J. Hydrological Processes 2005 19/9 (1871-1882)
372
HYDROLOGY
In the past 30 years, the measured annual river flow of the Yellow River has declined significantly. After adding the diverted
water back to get the вЂ�naturalвЂ™ annual river flow, the tendency
of decrease can still be seen. This indicates that the river flow
renewability of the Yellow River has changed. The river flow
renewability is indexed as the ratio of annual вЂ�naturalвЂ™ river flow
to annual precipitation over a river drainage basin, where the
вЂ�naturalвЂ™ river flow is the measured annual river flow plus the
annual вЂ�netвЂ™ water diversion from the river. By using this index,
based on the data from the drainage area between Hekouzhen
and Longmen stations on the middle Yellow River, a study has
been made of the river flow renewability of the Yellow River in
the changing environment of the past 50 years. The river flow
renewability index (Irr ) in the drainage area between Hekouzhen
and Longmen in the middle Yellow River basin has been found to
decline significantly with time. In the meantime, annual precipitation decreased, annual air temperature increased, but the area
of water and soil conservation measures has been increased. It
has been found that Irr is positively correlated with the areal averaged annual precipitation, but negatively correlated with annual
air temperature. There is close, negative correlation between Irr
and the area of water and soil conservation measures including
land terracing, tree and grass planting and checkdam building,
implying that water and soil conservation measures have reduced
the river flow renewability. Copyright В© 2005 John Wiley &
Sons, Ltd.
1946 A modified Xinanjiang model and its application in
northern China
Hu C., Guo S., Xiong L. and Peng D. Nordic Hydrology 2005
36/2 (175-192)
The Xinanjiang model has been widely used in the humid regions
in southern China as a basic tool for rainfall - runoff simulation,
flood forecasting and water resources planning and management.
However, its performance in the arid and semi-arid regions of
northern China is usually not so good as in the humid regions.
A modified Xinanjiang model, in which runoff generation in
the watershed is based on both infiltration excess and saturation
excess runoff mechanisms, is presented and discussed. Three
different watersheds are selected for assessing and comparing
the performance of the Xinanjiang model, the modified Xinanjiang model, the VIC model and the TOPMODEL in rainfall runoff simulation. It is found that the modified Xinanjiang model
performs better than the Xinanjiang model, and the models considering the Horton and Dunne runoff generation mechanisms
are slightly better than those models considering the single runoff generation mechanism in semi-arid areas. It is suggested that
the infiltration excess runoff mechanism should be included in
rainfall - runoff models in and and semi-arid regions. В© IWA
Publishing 2005.
1947 Regional flow duration curve for a Himalayan river
Chenab
Arora M., Goel N.K., Singh P. and Singh R.D. Nordic Hydrology
2005 36/2 (193-206)
This study is carried out with the objective of examining the
effect of altitude on water availability estimates for the various
sub-basins of the Chenab river basin (mean elevation of the basin
is 3600 m), which is a snow-fed Himalayan river basin located
in the western Himalayas. This basin covers all three Himalayan
ranges, i.e. outer, middle and greater Himalayas. For this study,
the daily flow data of 11 gauging sites varying from 14 years to
23 years in the Chenab river basin are utilised. The other important information related to the physiography, hydrology and
meteorology, etc, for the region are derived from the available
literature and maps. The daily flow data of nine gauging sites
are utilised for developing the regional relationships for water
availability computations. These relationships are tested over
the remaining two gauging sites. The regional relationships are
developed using three different approaches. These approaches
include: (i) parameter regionalisation for individual gauged sites
of selected probability distribution, (ii) regionalisation of dependable flows and (iii) parameter regionalisation for the region
as a whole of the selected probability distribution. The different
methods are compared and discussed in detail. It is observed
that the flow for a given dependability increases with catchment
area and decreases with altitude. The flows of the catchments
at higher altitudes exhibit larger variability in comparison to the
catchments at lower altitudes. The regional relationships are
recommended for the use of field engineers. В© IWA Publishing
2005.
1948 Hidrological effects of the electrical and agricultural
uses in the basin of the Laja river (center-south of Chile)
(Spanish) (Efectos hidrolВґogicos de los usos elВґectrico y agrcola
en la cuenca del ro Laja (Chile centro-sur))
Mardones M. and Vargas J. Revista de Geografia Norte Grande
2005 -/33 (89-102)
Surface hydrological responses to hydroelectric and agricultural
use, are evaluated of the Laja river basin (Chile) and the associated lake Laja. A drop of 27 m is observed in the lake water
level with respect to normal hydrologic regime, for the 1972
to 1999 period; it correlates directly with hydroelectric power
production (r2 = 0,78). In addition, the drainage network of the
upper river basin has been modified completely. The impact of
this use on the hydrologic balance of the Andean sector is weak
(-3,7% of total precipitations), due to lack of consumption. In
the lower basin, water consumption for irrigation corresponds to
an annual average of 22,8% of the Laja river volume, resulting in
a negative hydrological balance equivalent to 36,8%, of the total
annual rainfall.
1949 Linking riparian dynamics and groundwater: An ecohydrologic approach to modeling groundwater and riparian
vegetation
Baird K.J., Stromberg J.C. and Maddock III T. Environmental
Management 2005 36/4 (551-564)
The growing use of global freshwater supplies is increasing the
need for improved modeling of the linkage between groundwater and riparian vegetation. Traditional groundwater models
such as MODFLOW have been used to predict changes in regional groundwater levels, and thus riparian vegetation potential attributable to anthropogenic water use. This article describes an approach that improves on these modeling techniques
through several innovations. First, evapotranspiration from riparian/wetland systems is modeled in a manner that more realistically reflects plant ecophysiology and vegetation complexity.
In the authorsвЂ™ model programs (RIP-ET and PRE-RIP-ET), the
single, monotonically increasing evapotranspiration flux curve
in traditional groundwater models is replaced with a set of ecophysiologically based curves, one for each plant functional group
present. For each group, the curve simulates transpiration declines that occur both as water levels decline below rooting depths
and as waters rise to levels that produce anoxic soil conditions.
Accuracy is further improved by more effective spatial handling
of vegetation distribution, which allows modeling of surface elevation and depth to water for multiple vegetation types within
each large model cell. The use of RIP-ET in groundwater models can improve the accuracy of basin scale estimates of riparian
evapotranspiration rates, riparian vegetation water requirements,
and water budgets. Two case studies are used to demonstrate
that RIP-ET produces significantly different evapotranspiration
estimates than the traditional method. When combined with
vegetation mapping and a supporting program (RIP-GIS), RIPET also enables predictions of riparian vegetation response to
water use and development scenarios. The RIP-GIS program
links the head distribution from MODFLOW with surface digital elevation models, producing moderate- to high-resolution
depth-to-groundwater maps. Together with information on plant
rooting depths, these can be used to predict vegetation response
to water allocation decisions. The different evapotranspiration
outcomes produced by traditional and RIP-ET approaches affect
resulting interpretations of hydro-vegetation dynamics, including
the effects of groundwater pumping stress on existing habitats,
and thus affect subsequent policy decisions. В© 2005 Springer
Science+Business Media, Inc.
1950 Regional hydrological modelling in Benin (West Africa): Uncertainty issues versus scenarios of expected future
environmental change
Bormann H. Physics and Chemistry of the Earth 2005 30/8-10
(472-484)
The conceptual, hydrological UHP model was used to calculate
regional and seasonal to long-term water fluxes of several meso-
HYDROLOGY
scale catchments within the upper OuВґemВґe basin in central Benin.
To analyse the quality of the simulations in addition to standard
model validation techniques (e.g., split sampling test, multi-site
and multi-scale validation), different methods were applied to assess the orders of magnitude of input data uncertainty and model
uncertainty (e.g., Monte-Carlo-analysis, rainfall data analysis).
To evaluate the suitability of the model to be used for environmental change studies, finally the detected uncertainties were set
into relation to the effects of environmental change scenarios for
different regional scale catchments in central Benin. Main result
was the fact that all "signal-to-noise ratios" of model-scenariouncertainty combinations were positive and most of the ratios
were even high. Thus on the seasonal time scale, the environmental effects calculated by the model were significantly larger
than the uncertainties caused by imperfect model parameters and
input data. Nevertheless uncertainties were detected to have a
potentially significant impact on the simulation results (esp. on
the event scale) although the model calculates the water fluxes of
the subhumid catchments well with regard to several statistical
quality measures (water balance, model efficiency, coefficient
of variation, etc.). Dominating uncertainties are the input data
(rainfall in particular), which may cause both errors in the calculated hydrological processes at the event scale and biases in
the long-term water balance. Therefore implausible data sets
need to be rejected. With regard to the scenarios all environmental changes may cause significant effects on the long-term
water balance: land use change, soil degradation and decreasing
rainfall. Concerning the total annual stream flow the realistic
scenarios of an expected rainfall decrease and an increasing soil
degradation due to land use change in the next 20 years partly
leads to a compensation of the individual effects (e.g., decrease
caused by decreasing rainfall versus increase caused by decreasing soil storage capacity and increasing curve number), while
other water related indicators (e.g., the length of the vegetation
period defined by the time of exceeding a certain root zone soil
moisture; annual actual evapotranspiration as an indicator for
plant productivity) decrease significantly. В© 2005 Elsevier Ltd.
All rights reserved.
1951 Assessing the effects of land use change on soil physical properties and hydrological processes in the sub-humid
tropical environment of West Africa
Giertz S., Junge B. and DiekkrВЁuger B. Physics and Chemistry of
the Earth 2005 30/8-10 (485-496)
Land use is a key parameter in the hydrologic cycle. Tropical
Africa is affected by intense land use change since decades, particularly deforestation and conversion to agricultural land. The
aim of this study is to analyse the effects of land use change
on the hydrologic processes and soil physical properties in a
small catchment (Aguima catchment) in central Benin. Results
from pedological, pedobiological and hydrological investigations
within the Aguima catchment were taken into account. The effects of land use change on hydrologic processes were analysed
by comparing two sub-catchments of the Aguima catchment with
different land use (savannah/forest and agricultural land use).
The study is part of the GLOWA IMPETUS project, which examines the effects of global change on the water cycle and water
availability on a regional scale in Morocco and Benin. The
investigations of this study revealed that due to reduced activity
of the macrofauna the infiltration capacity is significantly lower
in cultivated soils than in savannah and forest. This causes higher
surface runoff and soil loss rates, which was also determined on
erosion plots. The increased soil loss on fields has effects on soil
physical properties like increase of gravel content and reduction
of field capacity. The impact of reduced vegetation cover on the
soil water dynamics was examined with soil moisture measurements on different land use. Due to higher evapotranspiration and
water withdrawal the soil water content on forest and savannah
plots was lower than on agricultural fields. The difference in the
water yield of the forested and cultivated catchments was over
120 mm in the dry year 2001 and about 70 mm in the wetter year
2002. В© 2005 Pubilshed by Elsevier Ltd.
373
1952 The application of simple methods using remote sensing data for the regional validation of a semidistributed hydrological catchment model
Wegehenkel M., Jochheim H. and Kersebaum K.C. Physics and
Chemistry of the Earth 2005 30/8-10 (575-587)
Simulation runs of a semidistributed hydrological conceptual
catchment model were performed using a spatial data set from a
mesoscale catchment located at the moraine landscape of NorthEast Germany. The simulation quality of the model was estimated by comparing measured daily actual evapotranspiration
rates, soil water contents and discharge rates with the corresponding simulated model outputs. Additionally, six LandsatTM5-subsets covering the catchment were used to calculate the
Normalized Difference Vegetation Index (NDVI). These NDVIdistributions were compared with the corresponding simulated
regional distributions of actual evapotranspiration (ETr) rates. A
visual analysis of the spatial distribution patterns of the NDVI and
of the simulated ETr-rates shows some correspondences. However, the spatial variability of the NDVI-patterns was distinctly
higher in comparison with the variability of the ETr-rates calculated by the model. We analyzed the coefficients of correlation
R between the patterns of the NDVI and the simulated ETr-rates
separately for the land cover classes arable land, meadows, coniferous, deciduous and mixed forests. For arable land R ranged
within 0.77 and 0.10, for meadows within 0.79 and 0.10, for
coniferous forests between 0.73 and 0.10, for deciduous forests
between 0.88 and 0.10 as well as for mixed forests between 0.67
and 0.10. The spatial distributions of simulated high and low
ETr-rates were mainly correlated with the spatial distributions of
forest areas, arable land, water bodies and settlements. В© 2005
Elsevier Ltd. All rights reserved.
1953 Runoff modelling using radar data and flow measurements in a stochastic state space approach
KrВЁamer S., Grum M., Verworn H.- R. and Redder A. Water
Science and Technology 2005 52/5 (1-8)
In urban drainage the estimation of runoff with the help of models is a complex task. This is in part due to the fact that rainfall,
the most important input to urban drainage modelling, is highly
uncertain. Added to the uncertainty of rainfall is the complexity
of performing accurate flow measurements. In terms of deterministic modelling techniques these are needed for calibration
and evaluation of the applied model. Therefore, the uncertainties
of rainfall and flow measurements have a severe impact on the
model parameters and results. To overcome these problems a new
methodology has been developed which is based on simple rain
plane and runoff models that are incorporated into a stochastic
state space model approach. The state estimation is done by using
the extended Kalman filter in combination with a maximum likelihood criterion and an off-line optimization routine. This paper
presents the results of this new methodology with respect to the
combined consideration of uncertainties in distributed rainfall
derived from radar data and uncertainties in measured flows in
an urban catchment within the Emscher river basin, Germany. В©
IWA Publishing 2005.
1954 Surface models for coupled modelling of runoff and
sewer flow in urban areas
Ettrich N., Steiner K., Thomas M. and Rothe R. Water Science
and Technology 2005 52/5 (25-33)
Traditional methods fail for the purpose of simulating the complete flow process in urban areas as a consequence of heavy rainfall and as required by the European Standard EN-752 since the
bi-directional coupling between sewer and surface is not properly
handled. The new methodology, developed in the EUREKAproject RisUrSim, solves this problem by carrying out the runoff
on the basis of shallow water equations solved on high-resolution
surface grids. Exchange nodes between the sewer and the surface, like inlets and manholes, are located in the computational
grid and water leaving the sewer in case of surcharge is further
distributed on the surface. Dense topographical information is
needed to build a model suitable for hydrodynamic runoff calculations; in urban areas, in addition, many line-shaped elements
like houses, curbs, etc. guide the runoff of water and require
polygonal input. Airborne data collection methods offer a great
chance to economically gather densely sampled input data. В©
IWA Publishing 2005.
374
HYDROLOGY
1955 Development and implementation of a real time control
strategy for the sewer system of the city of Vienna
Fuchs L. and Beeneken T. Water Science and Technology 2005
52/5 (187-194)
The paper describes the realization of a real-time control for the
Vienna sewer system. The project is scheduled for completion for
2004. The 3.5 year project comprises all planning stages starting
with the recording of data up to the planning of measuring and
controlling units. The concrete steps of the planning stages are
explained. A measuring system including 25 rainfall measurements, 40 flow measurements and 20 water level measurements
is implemented as an online system. This measuring system is
designed to achieve two objectives, on the one hand the real-time
control and on the other hand the callibration of the model that
is used for the hydrodynamic sewer system simulation. The approx. 53,000 pipes have served to generate a coarse network of no
more than approx. 2,600 pipes. The area data were derived with
high accuracy from available aerial photograph interpretations.
With simulation runs of a rule-based control software the system
operation was examined. A self-learning system will improve
the rule basis. A forecasting model that uses weather observation
radar will additionally influence the controlling decisions. The
findings from the investigations are immediately considered in
the planning of measuring and control units. The simulated
results for the first phase of implementation, which demonstrate
the benefit of RTC for the Vienna sewer system, are explained.
В© IWA Publishing 2005.
1956 Flooding in the future - Predicting climate change,
risks and responses in urban areas
Ashley R.M., Balmfort D.J., Saul A.J. and Blanskby J.D. Water
Science and Technology 2005 52/5 (265-273)
Engineering infrastructure is provided at high cost and is expected
to have a useful operational life of decades. However, it is clear
that the future is uncertain. Traditional approaches to designing
and operating urban storm drainage assets have relied on past
performance of natural systems and the ability to extrapolate this
performance, together with that of the assets across the usable
lifetime. Whether or not climate change is going to significantly
after future weather patterns in Europe, it is clear that it is now
incumbent on designers and operators of storm drainage systems
to prepare for greater uncertainty in the effectiveness of storm
drainage systems. A recent UK Government study considered
the potential effects of climate and socio-economic change in the
UK in terms of four future scenarios and what the implications
are for the performance of existing storm drainage facilities. In
this paper the modelling that was undertaken to try to quantify
the changes in risk, together with the effectiveness of responses
in managing that risk, are described. It shows that flood risks
may increase by a factor of almost 30 times and that traditional
engineering measures alone are unlikely to be able to provide
protection. В© IWA Publishing 2005.
1957 SIPSON - Simulation of interaction between pipe flow
and surface overland flow in networks
Л‡ et al. Water SciDjordjeviВґc S., ProdanoviВґc D., MaksimoviВґc C.
ence and Technology 2005 52/5 (275-283)
The new simulation model, named SIPSON, based on the Preissmann finite difference method and the conjugate gradient
method, is presented in the paper. This model simulates conditions when the hydraulic capacity of a sewer systems exceeded,
pipe flow is pressurized, the water flows out from the piped
system to the streets, and the inlets cannot capture all the runoff.
In the mathematical model, buried structures and pipelines, together with surface channels, make a horizontally and vertically
looped network involving a complex interaction of flows. In this
paper, special internal boundary conditions related to equivalent
inlets are discussed. Procedures are described for the simulation
of manhole cover loss, basement flooding, the representation of
street geometry, and the distribution of runoff hydrographs between surface and underground networks. All these procedures
are built into the simulation model. Relevant issues are illustrated on a set of examples, focusing on specific parameters and
comparison with field measurements of flooding of the Motilal ki Chal catchment (Indore, India). Satisfactory agreement
of observed and simulated hydrographs and maximum surface
flooding levels is obtained. It is concluded that the presented
approach is an improvement compared to the standard "virtual
reservoir" approach commonly applied in most of the models. В©
IWA Publishing 2005.
1958 Remarks about definition and classification of floods
(Polish) (W sprawie definicji powodzi)
Byczkowski A. Przeglad Geofizyczny 2005 50/1-2 (73-76)
As generally assumed a flood occurs when the river overtops
and inundates the floodplain. The paper suggests extension of
the definition and classification of floods. The flood should be
defined as the phenomenon of inundation of the certain territory
with the waters of various genesis affecting: threat of human life
as well as the economical and moral losses. In proposed classification the floods are differentiated on: the river ones, local
accumulation of the rain or snowmelt water and coastal floods.
1959 The Orinoco River basin: Hydrographic view and its
hydrological balance (Spanish) (La cuenca del ro Orinoco:
VisiВґon hidrogrВґafica y balance hdrico)
Silva LeВґon G. Revista Geografica Venezolana 2005 46/1 (75-108)
The international Orinoco River basin is described, referring to
location, limits, dimensions, extension, regions, cities, fluvial
integration, climate, runoff regime and main tributaries. Then,
the hydrological balance of the basin is approached, simplifying
the general equation to the case of the annual average, in which
the contribution by rainfall is equal to the exit by runoff and
evapotranspiration. First, a balance adjusted to the historical
average of 14.850 m3/s that has the Orinoco River in Puerto
Ayacucho is accomplished, to whose basin of 342.000 Km2 an
average of 2.660 mm/year of rainfall and 1.260 mm/year of evapotranspiration is calculated, resulting in good hydrological yield
indicatives: productivity of 43 l/s/Km2 and runoff coefficient of
51%. This balance is extrapolated to other points of the Orinoco River, up streams and down streams, including its affluents.
Finally, preliminary balances are obtained from hydrographic
regions and from countries.
1960 Flow regime alterations under changing climate in two
river basins: Implications for freshwater ecosystems
Gibson C.A., Meyer J.L., Poff N.L. et al. River Research and
Applications 2005 21/8 (849-864)
We examined impacts of future climate scenarios on flow regimes
and how predicted changes might affect river ecosystems. We
examined two case studies: Cle Elum River, Washington, and
Chattahoochee-Apalachicola River Basin, Georgia and Florida.
These rivers had available downscaled global circulation model
(GCM) data and allowed us to analyse the effects of future climate
scenarios on rivers with (1) different hydrographs, (2) high future
water demands, and (3) a river-floodplain system. We compared
observed flow regimes to those predicted under future climate
scenarios to describe the extent and type of changes predicted
to occur. Daily stream flow under future climate scenarios was
created by either statistically downscaling GCMs (Cle Elum)
or creating a regression model between climatological parameters predicted from GCMs and stream flow (ChattahoocheeApalachicola). Flow regimes were examined for changes from
current conditions with respect to ecologically relevant features
including the magnitude and timing of minimum and maximum
flows. The Cle ElumвЂ™s hydrograph under future climate scenarios
showed a dramatic shift in the timing of peak flows and lower low
flow of a longer duration. These changes could mean higher summer water temperatures, lower summer dissolved oxygen, and
reduced survival of larval fishes. The Chattahoochee-Apalachicola basin is heavily impacted by dams and water withdrawals for
human consumption; therefore, we made comparisons between
pre-large dam conditions, current conditions, current conditions
with future demand, and future climate scenarios with future demand to separate climate change effects and other anthropogenic
impacts. Dam construction, future climate, and future demand
decreased the flow variability of the river. In addition, minimum
flows were lower under future climate scenarios. These changes
could decrease the connectivity of the channel and the floodplain,
decrease habitat availability, and potentially lower the ability of
the river to assimilate wastewater treatment plant effluent. Our
study illustrates the types of changes that river ecosystems might
HYDROLOGY
experience under future climates. Copyright В© 2005 John Wiley
& Sons, Ltd.
1961 Effects of stream flow intermittency on riparian vegetation of a semiarid region river (San Pedro River, Arizona)
Stromberg J.C., Bagstad K.J., Leenhouts J.M. et al. River Research and Applications 2005 21/8 (925-938)
The San Pedro River in the southwestern United States retains
a natural flood regime and has several reaches with perennial
stream flow and shallow ground water. However, much of the
river flows intermittently. Urbanization-linked declines in regional ground-water levels have raised concerns over the future status of the riverine ecosystem in some parts of the river,
while restoration-linked decreases in agricultural ground-water
pumping are expected to increase stream flows in other parts.
This study describes the response of the streamside herbaceous
vegetation to changes in stream flow permanence. During the
early summer dry season, streamside herbaceous cover and
species richness declined continuously across spatial gradients
of flow permanence, and composition shifted from hydric to
mesic species at sites with more intermittent flow. Hydrologic
threshold values were evident for one plant functional group:
Schoenoplectus acutus, Juncus torreyi, and other hydric riparian
plants declined sharply in cover with loss of perennial stream
flow. In contrast, cover of mesic riparian perennials (including
Cynodon dactylon, an introduced species) increased at sites with
intermittent flow. Patterns of hydric and mesic riparian annuals
varied by season: in the early summer dry season their cover
declined continuously as flow became more intermittent, while
in the late summer wet season their cover increased as the flow
became more intermittent. Periodic drought at the intermittent
sites may increase opportunities for establishment of these annuals during the monsoonal flood season. During the late summer
flood season, stream flow was present at most sites, and fewer
vegetation traits were correlated with flow permanence; cover
and richness were correlated with other environmental factors
including site elevation and substrate nitrate level and particle
size. Although perennial-flow and intermittent-flow sites support
different streamside plant communities, all of the plant functional
groups are abundant at perennial-flow sites when viewing the
ecosystem at broader spatial and temporal scales: mesic riparian
perennials are common in the floodplain zone adjacent to the
river channel and late-summer hydric and mesic annuals are periodically abundant after large floods. Copyright В© 2005 John
Wiley & Sons, Ltd.
1962 Integration of weather radar data into a raster GIS
framework for improved flood estimation
Yu B., Seed A., Pu L. and Malone T. Atmospheric Science Letters
2005 6/1 (66-70)
Weather radar data were used to estimate rainfall fields at 2-km
resolution for a large flood event in 1999 in south-east Queensland, Australia, and subsequently integrated with a raster-based
hydrologic model (RAMS) for runoff generation and flow routing. Gauge-based and radar-based temporal storm patterns are
quite similar for the storm event. Agreement between gaugebased and radar-based event rainfall totals is not as good as that
for spatially averaged intensities. Correlation between gaugebased and radar-based rainfall measurements is not sensitive to
the exponent value in the Z-R relationship for the event tested.
The hydrologic model with 4 parameters for the entire 13 600km2 catchment works very well when calibrated against the
measured hydrograph. An overall model efficiency of 0.61 is
achieved with respect to predicted peak discharge for 17 validation sites in the catchment. RAMS compares favourably with
URBS, a rainfall-runoff model using gauge-based measurements
currently in use for flood forecasting purposes. Copyright В©
2005 Royal Meteorological Society.
1963 Retrospective comparison of Watershed Analysis Risk
Management Framework and Hydrologic Simulation Program Fortran applications to Mica Creek Watershed
Chen C.W., Herr J.W., Goldstein R.A. et al. Journal of Environmental Engineering 2005 131/9 (1277-1284)
As part of an ongoing watershed model comparison program
for forested watersheds, Watershed Analysis Risk Management
Framework (WARMF V5.18) and Hydrologic Simulation Pro-
375
gram Fortran (HSPF V10) were independently applied to the
Mica Creek Watershed in Idaho. A comprehensive model comparison was made in terms of watershed delineation, hydrologic
formulations, model parameterization, meteorological data, hydrologic calibration, and hydrologic verification. Comparison
was not made for water quality, which was not simulated in the
HSPF application. It was concluded that WARMF is a mechanistic model structured to simulate the hydrologic processes,
whereas HSPF is an empirical water budget model. The WARMF
is suitable for application to forested watersheds. It successfully
predicted stream flows comparable to measured values. The
HSPF results were also good, if one ignores an unrealistic amount
of water loss to inactive groundwater and an empirical treatment
of rain-on-snow events. Journal of Environmental Engineering
В© ASCE.
1964 Runoff and soil moisture relationships in a small
forested basin in the Sistema Central Ranges (Spain)
Martnez- FernВґandez J., Ceballos A., Casado S. et al. IAHS-AISH
Publication 2005 -/299 (31-36)
In the present work we analyse runoff yield in a small Mediterranean basin with respect to soil moisture dynamics. The aim
was to observe the behaviour of the basin in terms of the generation of runoff in periods in which maximum water deficit
occurs in the soil. Despite the abundant precipitation in the
mountainous regions of the Mediterranean area, the joint action
of the climatic conditions prevailing in the growing season and
water interception and consumption by the forest may seriously
affect the generation of runoff over a considerable part of the
year.
1965 The effects over time of an arterial drainage scheme
on the flood magnitude-return period relations
Bhattarai K.P. and OвЂ™Connor H.M. IAHS-AISH Publication 2005
-/299 (67-74)
Arterial Drainage Schemes (ADSs) were implemented on Irish
rivers for the purposes of improving the land drainage and reducing the frequency and extent of overland flooding. Such
ADSs mainly involved the deepening and widening of the river
channels in order to increase their discharge-carrying capacity,
thereby, affecting not only the basinsвЂ™ response to rainfall but also
their peak discharge (QT )-return period (T) relation. Earlier Irish
studies involving the effects of ADS on a catchmentвЂ™s QT -T relation found that the post-drainage QT of an ADS-catchment was
always larger, for the same T, in comparison to its pre-drainage
counterpart. The current study focuses on investigating whether
such effects have persisted in the ADS-catchments, or died out
with the passage of time. Results of analysis on 16 ADS and 6non-ADS catchments show that the ADS (post-1945)-catchments
have experienced major changes in the QT -T relation over time,
whereas such changes are less pronounced in other catchments.
1966 The change in flood regime along the Lower Jordan
River: Its influence on flood plain land use
Klein M. IAHS-AISH Publication 2005 -/299 (205-216)
Cooperation among riparian parties along the Lower Jordan
River (LJR) may promote development of the regionвЂ™s natural
resources. Cooperation requires understanding of the riverвЂ™s
present flow regime, water quality and current land use in the
flood plain. The average annual flow in the LJR has decreased
from 1166 Mm3 year-1 (1926-1945) to 167 Mm3 year-1 (19782000), of which about 70% (120 Mm3 ), are of good water quality.
Due to the extremely dry years, the allocation of water to the state
of Jordan of 50 Mm3 year-1 after the 1994 Peace Agreement and
the barrage built on the Yarmouk (YR) at Adasia, the average
yearly flow of the last decade was less than 120 Mm3 . At present
the riverвЂ™s cross section area is in a re-adjustment phase and is
becoming much smaller. The LJR flood plain is not inhabited
and the population lives outside the area, yet the flood plain is
used for agricultural purposes.
1967 Hybrid model for derivation of synthetic unit
hydrograph
Bhunya P.K., Ghosh N.C., Mishra S.K. et al. Journal of Hydrologic Engineering 2005 10/6 (458-467)
376
HYDROLOGY
Splitting the Nash single linear reservoir into two serially connected reservoirs of unequal storage coefficients (one hybrid unit)
for a physically realistic response, a hybrid model is introduced
for derivation of a synthetic unit hydrograph. Empirical relations are given for estimation of the two storage coefficients
from known peak flow (qp ) and time to peak (tp ). The hybrid model with two serially connected units is found to work
significantly better than the most widely used methods such as
those of Snyder, the Soil Conservation Service (SCS), and the
two-parameter gamma distribution when tested on synthetically
generated data and the data from four catchments from India and
one from Turkey. The workability of the proposed approach was
also tested for partial and no data availability situations. Journal
of Hydrologic Engineering В© ASCE.
1968 Analyses of flow mechanism based on master recession
curves
Mizumura K. Journal of Hydrologic Engineering 2005 10/6 (468476)
A theoretical analysis derives that master recession curves on
log paper indicate the physical occurrence of stream flows. The
master recession curves in this study are generated by one-dimensional overland flow without and with lateral flow and groundwater flow. One-dimensional overland flow is also classified by
assumption of the energy slope and kinematic or diffusion wave
models. These theoretical results are coincident with the slopes
of the observed master recession curves of the hydrographs. The
slopes of the master recession curve of water depth and the discharge hydrographs on the log paper designate the predominancy
of river discharge. These results predict the governing causes of
river discharge occurrence during the master recession period.
When the lateral flow is predominant, the master recession curve
is not definitely determined. The observation data indicate that
the slopes of the master recession curves are found to be independent of the initial conditions of channel flows, spatially
varied rainfalls, moving rainstorms, etc. Journal of Hydrologic
Engineering В© ASCE.
1969 Comparison of several flood forecasting models in
Yangtze River
Chau K.W., Wu C.L. and Li Y.S. Journal of Hydrologic Engineering 2005 10/6 (485-491)
In a flood-prone region, quick and accurate flood forecasting
is imperative. It can extend the lead time for issuing disaster
warnings and allow sufficient time for habitants in hazardous
areas to take appropriate action, such as evacuation. In this
paper, two hybrid models based on recent artificial intelligence
technology, namely, the genetic algorithm-based artificial neural
network (ANN-GA) and the adaptive-network-based fuzzy inference system (ANFIS), are employed for flood forecasting in a
channel reach of the Yangtze River in China. An empirical linear
regression model is used as the benchmark for comparison of
their performances. Water levels at a downstream station, HanKou, are forecasted by using known water levels at the upstream
station, Luo-Shan. When cautious treatment is made to avoid
overfitting, both hybrid algorithms produce better accuracy in
performance than the linear regression model. The ANFIS model
is found to be optimal, but it entails a large number of parameters. The performance of the ANN-GA model is also good,
yet it requires longer computation time and additional modeling
parameters. Journal of Hydrologic Engineering В© ASCE.
1970 Optimal location of infiltration-based best management practices for storm water management
Perez- Pedini C., Limbrunner J.F. and Vogel R.M. Journal of
Water Resources Planning and Management 2005 131/6 (441448)
A distributed hydrologic model of an urban watershed in the
northeast United States was developed and combined with a
genetic algorithm to determine the optimal location of infiltration-based best management practices (BMPs) for storm water
management. The distributed, event-based hydrologic model integrates the curve number method with a distributed hydrologic
network model of the catchment using a system of 4,533 hydrologic response units (HRUs). The infiltration-based BMP was
conceptualized as an element that alters the infiltration/runoff
partitioning of the HRUs in which it was applied. The results
indicate that the optimal location and number of BMPs is a complex function of watershed network connectivity, flow travel time,
land use, distance to channel, and contributing area, requiring an
optimization approach of the type introduced here. A Pareto
frontier describing the trade-off between the number of BMPs,
representing project cost, and watershed flooding was developed.
Journal of Water Resources Planning and Management В© ASCE.
1971 Probabilistic nonlinear prediction of river flows
Tamea S., Laio F. and Ridolfi L. Water Resources Research 2005
41/9 (1-9)
[1] In the recent past the nonlinear prediction (NLP) method,
initially developed in the context of nonlinear time series analysis, has been successfully applied to river flow deterministic
forecasting. In this work a probabilistic approach to the NLP
method is proposed, which allows one to estimate the probability
distribution of the predicted discharge values and to quantify the
total uncertainty related to the forecast. An ensemble technique
is also proposed in order to optimize the choice of the parameter
values and to provide robustness to the model calibration. The
probabilistic NLP method is applied to a river flow time series,
giving results that confirm the effectiveness and reliability of the
proposed approach. Copyright 2005 by the American Geophysical Union.
1972 A Markov switching model for annual hydrologic time
series
AkintuЛ‡g B. and Rasmussen P.F. Water Resources Research 2005
41/9 (1-10)
[1] This paper investigates the properties of Markov switching
(MS) models (also known as hidden Markov models) for generating annual time series. This type of model has been used
in a number of recent studies in the water resources literature.
The model considered here assumes that climate is switching
between M states and that the state sequence can be described by
a Markov chain. Observations are assumed to be drawn from a
normal distribution whose parameters depend on the state variable. We present the stochastic properties of this class of models
along with procedures for model identification and parameter
estimation. Although, at a first glance, MS models appear to
be quite different from ARMA models, we show that it is possible to find an ARMA model that has the same autocorrelation
function and the same marginal distribution as any given MS
model. Hence, despite the difference in model structure, there
are strong similarities between MS and ARMA models. MS and
ARMA models are applied to the time series of mean annual
discharge of the Niagara River. Although it is difficult to draw
any general conclusion from a single case study, it appears that
MS models (and ARMA models derived from MS models) generally have stronger autocorrelation at higher lags than ARMA
models estimated by conventional maximum likelihood. This
may be an important property if the purpose of the study is the
analysis of multiyear droughts. Copyright 2005 by the American
Geophysical Union.
1973 Simulation of flood flow in a river system using artificial
neural networks
Shrestha R.R., Theobald S. and Nestmann F. Hydrology and
Earth System Sciences 2005 9/4 (313-321)
Artificial neural networks (ANNs) provide a quick and flexible
means of developing flood flow simulation models. An important
criterion for the wider applicability of the ANNs is the ability
to generalise the events outside the range of training data sets.
With respect to flood flow simulation, the ability to extrapolate
beyond the range of calibrated data sets is of crucial importance.
This study explores methods for improving generalisation of
the ANNs using three different flood events data sets from the
Neckar River in Germany. An ANN-based model is formulated
to simulate flows at certain locations in the river reach, based
on the flows at upstream locations. Network training data sets
consist of time series of flows from observation stations. Simulated flows from a one-dimensional hydrodynamic numerical
model are integrated for network training and validation, at a
river section where no measurements are available. Network
structures with different activation functions are considered for
improving generalisation. The training algorithm involved back-
HYDROLOGY
propagation with the Levenberg-Marquardt approximation. The
ability of the trained networks to extrapolate is assessed using
flow data beyond the range of the training data sets. The results
of this study indicate that the ANN in a suitable configuration
can extend forecasting capability to a certain extent beyond the
range of calibrated data sets. В© EGU.
1974 Precipitation forecasts and their uncertainty as input
into hydrological models
Kobold M. and SuЛ‡selj K. Hydrology and Earth System Sciences
2005 9/4 (322-332)
Torrential streams and fast runoff are characteristic of most Slovenian rivers and extensive damage is caused almost every year
by rainstorms affecting different regions of Slovenia. Rainfallrunoff models which are tools for runoff calculation can be used
for flood forecasting. In Slovenia, the lag time between rainfall
and runoff is only a few hours and on-line data are used only
for now-casting. Predicted precipitation is necessary in flood
forecasting some days ahead. The ECMWF (European Centre
for Medium-Range Weather Forecasts) model gives general forecasts several days ahead while more detailed precipitation data
with the ALADIN/SI model are available for two days ahead.
Combining the weather forecasts with the information on catchment conditions and a hydrological forecasting model can give
advance warning of potential flooding notwithstanding a certain
degree of uncertainty in using precipitation forecasts based on
meteorological models. Analysis of the sensitivity of the hydrological model to the rainfall error has shown that the deviation in
runoff is much larger than the rainfall deviation. Therefore, verification of predicted precipitation for large precipitation events
was performed with the ECMWF model. Measured precipitation
data were interpolated on a regular grid and compared with the
results from the ECMWF model. The deviation in predicted
precipitation from interpolated measurements is shown with the
model bias resulting from the inability of the model to predict
the precipitation correctly and a bias for horizontal resolution of
the model and natural variability of precipitation. В© EGU.
1975 Coupling meteorological and hydrological models for
flood forecasting
Bartholmes J. and Todini E. Hydrology and Earth System Sciences 2005 9/4 (333-346)
This paper deals with the problem of analysing the coupling
of meteorological meso-scale quantitative precipitation forecasts
with distributed rainfall-runoff models to extend the forecasting
horizon. Traditionally, semi-distributed rainfall-runoff models
have been used for real time flood forecasting. More recently, increased computer capabilities allow the utilisation of distributed
hydrological models with mesh sizes from tenths of metres to
a few kilometres. On the other hand, meteorological models,
providing the quantitative precipitation forecast, tend to produce
average values on meshes ranging from slightly less than 10 to
200 kilometres. Therefore, to improve the quality of flood forecasts, the effects of coupling the meteorological and the hydrological models at different scales were analysed. A distributed
hydrological model (TOPKAPI) was developed and calibrated
using a 1 1 km mesh for the case of the river Po closed at
Ponte Spessa (catchment area c. 37 000 km2 ). The model
was then coupled with several other European meteorological
models ranging from the Limited Area Models (provided by
DMI and DWD) with resolutions from 0.0625В° 0.0625В°, to the
ECMWF ensemble predictions with a resolution of 1.85В° 1.85В°.
Interesting results, describing the coupled model behaviour, are
available for a meteorological extreme event in Northern Italy
(Nov. 1994). The results demonstrate the poor reliability of
the quantitative precipitation forecasts produced by meteorological models presently available; this is not resolved using the
Ensemble Forecasting technique, when compared with results
obtainable with measured rainfall. В© EGU.
1976 Flood forecasting using a fully distributed model:
Application of the TOPKAPI model to the Upper Xixian
Catchment
Liu Z., Martina M.L.V. and Todini E. Hydrology and Earth System Sciences 2005 9/4 (347-364)
TOPKAPI is a physically-based, fully distributed hydrological
model with a simple and parsimonious parameterisation. The
377
original TOPKAPI is structured around five modules that represent evapotranspiration, snowmelt, soil water, surface water and
channel water, respectively. Percolation to deep soil layers was
ignored in the old version of the TOPKAPI model since it was
not important in the basins to which the model was originally
applied. Based on published literature, this study developed a
new version of the TOPKAPI model, in which the new modules
of interception, infiltration, percolation, groundwater flow and
lake/ reservoir routing are included. This paper presents an application study that makes a first attempt to derive information
from public domains through the internet on the topography, soil
and land use types for a case study Chinese catchment - the Upper
Xixian catchment in Huaihe River with an area of about 10 000
km2 , and apply a new version of TOPKAPI to the catchment
for flood simulation. A model parameter value adjustment was
performed using six months of the 1998 dataset. Calibration
did not use a curve fitting process, but was chiefly based upon
moderate variations of parameter values from those estimated on
physical grounds, as is common in traditional calibration. The
hydrometeorological dataset of 2002 was then used to validate the
model, both against the outlet discharge as well as at an internal
gauging station. Finally, to complete the model performance
analysis, parameter uncertainty and its effects on predictive uncertainty were also assessed by estimating a posterior parameter
probability density via Bayesian inference. В© EGU.
1977 Flood forecasting using medium-range probabilistic
weather prediction
Gouweleeuw B.T., Thielen J., Franchello G. et al. Hydrology
and Earth System Sciences 2005 9/4 (365-380)
Following the developments in short- and medium-range weather
forecasting over the last decade, operational flood forecasting
also appears to show a shift from a so-called single solution or
вЂ�best guessвЂ™ deterministic approach towards a probabilistic approach based on ensemble techniques. While this probabilistic
approach is now more or less common practice and well established in the meteorological community, operational flood forecasters have only started to look for ways to interpret and mitigate
for end-users the prediction products obtained by combining socalled Ensemble Prediction Systems (EPS) of Numerical Weather
Prediction (NWP) models with rainfall-runoff models. This paper presents initial results obtained by combining deterministic
and EPS hindcasts of the global NWP model of the European
Centre for Medium-Range Weather Forecasts (ECMWF) with
the large-scale hydrological model LISFLOOD for two historic
flood events: the river Meuse flood in January 1995 and the river
Odra flood in July 1997. In addition, a possible way to interpret
the obtained ensemble based stream flow prediction is proposed.
В© EGU.
1978 Cascading model uncertainty from medium range
weather forecasts (10 days) through a rainfall-runoff model
to flood inundation predictions within the European Flood
Forecasting System (EFFS)
Pappenberger F., Beven K.J., Hunter N.M. et al. Hydrology and
Earth System Sciences 2005 9/4 (381-393)
The political pressure on the scientific community to provide
medium to long term flood forecasts has increased in the light of
recent flooding events in Europe. Such demands can be met by a
system consisting of three different model components (weather
forecast, rainfall-runoff forecast and flood inundation forecast)
which are all liable to considerable uncertainty in the input, output and model parameters. Thus, an understanding of cascaded
uncertainties is a necessary requirement to provide robust predictions. In this paper, 10-day ahead rainfall forecasts, consisting
of one deterministic, one control and 50 ensemble forecasts, are
fed into a rainfall-runoff model (LisFlood) for which parameter
uncertainty is represented by six different parameter sets identified through a Generalised Likelihood Uncertainty Estimation
(GLUE) analysis and functional hydrograph classification. The
runoff of these 52 6 realisations form the input to a flood inundation model (LisFlood-FP) which acknowledges uncertainty
by utilising ten different sets of roughness coefficients identified using the same GLUE methodology. Likelihood measures
for each parameter set computed on historical data are used to
give uncertain predictions of flow hydrographs as well as spatial
378
HYDROLOGY
inundation extent. This analysis demonstrates that a full uncertainty analysis of such an integrated system is limited mainly by
computer power as well as by how well the rainfall predictions
represent potential future conditions. However, these restrictions
may be overcome or lessened in the future and this paper establishes a computationally feasible methodological approach to the
uncertainty cascade problem. В© EGU.
1979 Assessing the performance of eight real-time updating
models and procedures for the Brosna River
Goswami M., OвЂ™Connor K.M., Bhattarai K.P. and Shamseldin
A.Y. Hydrology and Earth System Sciences 2005 9/4 (394-411)
The flow forecasting performance of eight updating models, incorporated in the Galway River Flow Modelling and Forecasting
System (GFMFS), was assessed using daily data (rainfall, evaporation and discharge) of the Irish Brosna catchment (1207 km2 ),
considering their one to six days lead-time discharge forecasts.
The Perfect Forecast of Input over the Forecast Lead-time scenario was adopted, where required, in place of actual rainfall
forecasts. The eight updating models were: (i) the standard
linear Auto-Regressive (AR) model, applied to the forecast errors (residuals) of a simulation (non-updating) rainfall-runoff
model; (ii) the Neural Network Updating (NNU) model, also
using such residuals as input; (iii) the Linear Transfer Function
(LTF) model, applied to the simulated and the recently observed
discharges; (iv) the Non-linear Auto-Regressive eXogenous-Input Model (NARXM), also a neural network-type structure, but
having wide options of using recently observed values of one or
more of the three data series, together with non-updated simulated outflows, as inputs; (v) the Parametric Simple Linear
Model (PSLM), of LTF-type, using recent rainfall and observed
discharge data; (vi) the Parametric Linear perturbation Model
(PLPM), also of LTF-type, using recent rainfall and observed
discharge data, (vii) n-AR, an AR model applied to the observed
discharge series only, as a naive updating model; and (viii) nNARXM, a naВЁД±ve form of the NARXM, using only the observed
discharge data, excluding exogenous inputs. The five GFMFS
simulation (non-updating) models used were the non-parametric
and parametric forms of the Simple Linear Model and of the
Linear Perturbation Model, the Linearly-Varying Gain Factor
Model, the Artificial Neural Network Model, and the conceptual
Soil Moisture Accounting and Routing (SMAR) model. As the
SMAR model performance was found to be the best among these
models, in terms of the Nash-Sutcliffe R2 value, both in calibration and in verification, the simulated outflows of this model only
were selected for the subsequent exercise of producing updated
discharge forecasts. All the eight forms of updating models for
producing lead-time discharge forecasts were found to be capable
of producing relatively good lead-1 (1-day ahead) forecasts, with
R2 values almost 90% or above. However, for higher lead time
forecasts, only three updating models, viz., NARXM, LTF, and
NNU, were found to be suitable, with lead-6 values of R2 about
90% or higher. Graphical comparisons were made of the leadtime forecasts for the two largest floods, one in the calibration
period and the other in the verification period. В© EGU.
1980 Utility of different data types for calibrating flood inundation models within a GLUE framework
Hunter N.M., Bates P.D., Horritt M.S. et al. Hydrology and Earth
System Sciences 2005 9/4 (412-430)
To translate a point hydrograph forecast into products for use
by environmental agencies and civil protection authorities, a hydraulic model is necessary. Typical one- and two-dimensional
hydraulic models are able to predict dynamically varying inundation extent, water depth and velocity for river and floodplain
reaches up to 100 km in length. However, because of uncertainties over appropriate surface friction parameters, calibration
of hydraulic models against observed data is a necessity. The
value of different types of data is explored in constraining the
predictions of a simple two-dimensional hydraulic model, LISFLOOD-FP. For the January 1995 flooding on the River Meuse,
The Netherlands, a flow observation data set has been assembled
for the 35-km reach between Borgharen and Maaseik, consisting
of Synthetic Aperture Radar and air photo images of inundation extent, downstream stage and discharge hydrographs, two
stage hydrographs internal to the model domain and 84 point
observations of maximum free surface elevation. The data set
thus contains examples of all the types of data that potentially
can be used to calibrate flood inundation models. 500 realisations of the model have been conducted with different friction
parameterisations and the performance of each realisation has
been evaluated against each observed data set. Implementation
of the Generalised Likelihood Uncertainty Estimation (GLUE)
methodology is then used to determine the value of each data set
in constraining the model predictions as well as the reduction in
parameter uncertainty resulting from the updating of generalised
likelihoods based on multiple data sources. В© EGU.
1981 An empirical method for estimating future flood risks
for flood warnings
Hlavcova K., Kohnova S., Kubes R. et al. Hydrology and Earth
System Sciences 2005 9/4 (431-448)
Since medium and long-term precipitation forecasts are still not
reliable enough, rough estimates of the degree of the extremity
of forthcoming flood events that might occur in the course of
dangerous meteorological situations approaching a basin could
be useful to decision-makers as additional information for flood
warnings. One approach to answering such a problem is to use
real-time data on the soil moisture conditions in a catchment in
conjunction with estimates of the extremity of the future rainfall and experience with the basinвЂ™s behaviour during historical
floods. A scenario-based method is proposed for such a future flood risk estimation, based on an a priori evaluation of the
extremity of hypothetical floods generated by combinations of
synthetic extreme precipitation and previously observed antecedent pre-flood basin saturations. The Hron river basin, located
in central Slovakia, was chosen as the pilot basin in the case
study. A time series of the basinвЂ™s average daily precipitation
was derived using spatial interpolation techniques. A lumped
HBV-type daily conceptual rainfall-runoff model was adopted
for modelling runoff. Analysis of the relationship of the modelled
historical pre-flood soil moisture and flood causing-precipitation
revealed the independence of both quantities for rainfall durations
lasting 1 to 5 days. The basinвЂ™s average annual maximum 1 to 5
day precipitation depths were analysed statistically and synthetic
extreme precipitation scenarios associated with rainfall depths
with return periods of 5, 20, 50 and 100 years, durations of 1 to 5
days and temporal distribution of extreme rainfall observed in the
past were set up for runoff simulation. Using event-based flood
simulations, synthetic flood waves were generated for random
combinations of the rainfall scenarios and historical pre-flood
soil moisture conditions. The effect of any antecedent basin
saturation on the extremity of floods was quantified empirically
and critical values of the basin saturation leading to floods with a
higher return period than the return period of precipitation were
identified. A method for implementing such critical values into
flood risk warnings in a hydrological forecasting and warning
system in the basin was suggested. В© EGU.
1982 Operational hydro-meteorological warning and realtime flood forecasting: The Piemonte Region case study
Rabuffetti D. and Barbero S. Hydrology and Earth System Sciences 2005 9/4 (457-466)
The development and implementation of a real-time flood forecasting system in the context of the Piemonte RegionвЂ™s hydrometeorological operational alert procedure is described. The
area of interest is the Upper Po River basin (north-west Italy) of
approximately 37 000 km2 and its river network of about 3000 km
and three big lakes. FloodWatch, a GIS-based decision support
system for real-time flood forecasting, has been developed and
used operationally at the Piemonte RegionвЂ™s Room for the Situation of Natural Hazards in Torino, Italy, since January 2000. The
system is linked directly to the telemetric gauges system, uses
daily quantitative precipitation and temperature forecasts issued
by the Regional Meteorological Service and automatically supplies operational forecasts of water-level and discharge at about
30 locations for up to 48 hours. Strengths and limits of the
system and its link with operational flood alert and management
are discussed. The case study presented is the October 2000
flood event, when the north-west of Italy experienced one of the
largest floods on record. Results highlight how the uncertainty
linked to the use of meteorological forecasts greatly influences
the quality of the hydrological forecasts. The proposed alert
HYDROLOGY
procedure, based on coded risk levels, can help effectively in
facing forecast uncertainties. В© EGU.
1983 A comparison of regionalisation methods for catchment model parameters
Parajka J., Merz R. and BlВЁoschl G. Hydrology and Earth System
Sciences 2005 9/3 (157-171)
In this study we examine the relative performance of a range
of methods for transposing catchment model parameters to ungauged catchments. We calibrate 11 parameters of a semi-distributed conceptual rainfall-runoff model to daily runoff and snow
cover data of 320 Austrian catchments in the period 1987-1997
and verify the model for the period 1976-1986. We evaluate the
predictive accuracy of the regionalisation methods by jack-knife
cross-validation against daily runoff and snow cover data. The results indicate that two methods perform best. The first is a kriging
approach where the model parameters are regionalised independently from each other based on their spatial correlation. The
second is a similarity approach where the complete set of model
parameters is transposed from a donor catchment that is most
similar in terms of its physiographic attributes (mean catchment
elevation, stream network density, lake index, areal proportion of
porous aquifers, land use, soils and geology). For the calibration
period, the median Nash-Sutcliffe model efficiency ME of daily
runoff is 0.67 for both methods as compared to ME=0.72 for the
at-site simulations. For the verification period, the corresponding efficiencies are 0.62 and 0.66. All regionalisation methods
perform similar in terms of simulating snow cover. В© 2005
Author(s). This work is licensed under a Creative Commons
License.
1984 Soil moisture-runoff relation at the catchment scale as
observed with coarse resolution microwave remote sensing
Scipal K., Scheffler C. and Wagner W. Hydrology and Earth
System Sciences 2005 9/3 (173-183)
Microwave remote sensing offers emerging capabilities to monitor global hydrological processes. Instruments like the two
dedicated soil moisture missions SMOS and HYDROS or the
Advanced Scatterometer onboard METOP will provide a flow of
coarse resolution microwave data, suited for macro-scale applications. Only recently, the scatterometer onboard of the European
Remote Sensing Satellite, which is the precursor instrument of
the Advanced Scatterometer, has been used successfully to derive
soil moisture information at global scale with a spatial resolution of 50 km. Concepts of how to integrate macroscale soil
moisture data in hydrologic models are however still vague. In
fact, the coarse resolution of the data provided by microwave
radiometers and scatterometers is often considered to impede
hydrological applications. Nevertheless, even if most hydrologic
models are run at much finer scales, radiometers and scatterometers allow monitoring of atmosphere-induced changes in regional
soil moisture patterns. This may prove to be valuable information
for modelling hydrological processes in large river basins (>10
000 km2 ). In this paper, ERS scatterometer derived soil moisture products are compared to measured runoff of the Zambezi
River in south-eastern Africa for several years (1992-2000). This
comparison serves as one of the first demonstrations that there
is hydrologic relevant information in coarse resolution satellite
data. The observed high correlations between basin-averaged
soil moisture and runoff time series (R2 >0.85) demonstrate that
the seasonal change from low runoff during the dry season to
high runoff during the wet season is well captured by the ERS
scatterometer. It can be expected that the high correlations are to
a certain degree predetermined by the pronounced inter-annual
cycle observed in the discharge behaviour of the Zambezi. To
quantify this effect, time series of anomalies have been compared. This analysis showed that differences in runoff from year
to year could, to some extent, be explained by soil moisture
anomalies. В© 2005 Author(s). This work is licensed under a
Creative Commons License.
1985 Using a spatio-temporal dynamic state-space model
with the EM algorithm to patch gaps in daily riverflow series
Amisigo B.A. and van de Giesen N.C. Hydrology and Earth
System Sciences 2005 9/3 (209-224)
A spatio-temporal linear dynamic model has been developed
for patching short gaps in daily river runoff series. The model
379
was cast in a state-space form in which the state variable was
estimated using the Kalman smoother (RTS smoother). The EM
algorithm was used to concurrently estimate both parameter and
missing runoff values. Application of the model to daily runoff
series in the Volta Basin of West Africa showed that the model
was capable of providing good estimates of missing runoff values
at a gauging station from the remaining time series at the station
and at spatially correlated stations in the same sub-basin. В© 2005
Author(s). This work is licensed under a Creative Commons
License.
1986 PAI-OFF: A new strategy of flash-flood forecasting
in quickly responding catchments (German) (PAI-OFF: Eine
neue Strategie zur Hochwasservorhersage in schnell reagierenden Einzugsgebieten)
Schmitz G.H., Cullmann J., GВЁorner W. et al. Hydrologie und
Wasserbewirtschaftung 2005 49/5 (226-234)
PAI-OFF (Process Modelling and Artificial Intelligence for Online Flood Forecasting) combines the reliability of physically
based, sophisticated modelling with the operational advantages
of Artificial Neural Networks (ANN), i.e. low computation times
and robustness, which form the basic requirements for flash-flood
forecasting. After presenting the theory of the new methodology, the results of a catchment related meteorological analysis
for generating storm scenarios serve as the input to a coupled
hydrologic/hydraulic model which is set up for a mountainous
catchment in East Germany. Operating on this basis, the catchment model for all realistically possible combinations of flood
formation builds a data bank consisting of corresponding input/output vectors. We complete the data bank for training the
ANN by adding yet more flood relevant data for characterizing
the hydrological and meteorological catchment situation prior
to a storm event. After training different ANN, a competitive
analysis of four different network architectures provides insight
in their problem-specific performances. After this preparatory
step, the selected ANN is applied for online flash-flood forecasting in the considered catchment, using an "unseen" storm
event, i.e. one which did not feature in the training process. The
convincing agreement between the predicted and observed flood
hydrographs underlines the application potential of the new PAIOFF methodology for online flood forecasting even in smaller
catchments.
1987 Long-term behaviour of low-flow parameters at gauges
of the Havel and Elbe river basins (German) (Langzeitverhalten von NiedrigwasserkenngrВЁoГџen von Pegeln des Havelgebietes und der Elbe)
Finke W. and Krause S. Hydrologie und Wasserbewirtschaftung
2005 49/5 (248-254)
Long time-series of streamflow indicate influences of climate
variations, land-use changes, water uses, and water-management
activities. In a comparison of streamflow data, the influences are
particularly intensive in the low-flow range, and they find their
reflection in low-flow parameters rather than in data measured
during flood-flow. For selected gauges on the River Elbe and
in the Havel river basin, long time-series of low-flow parameters
were examined for their long-term behaviour. This paper presents
the results of this comparative regional study.
1988 Statistical calculation of rainfall for various return
periods using the L-moment method (Spanish) (CВґalculo estadstico de lluvias para diversos perodos de retorno por el
mВґetodo de los momentos-L)
Comas F.M. Tecnologia del Agua 2005 25/264 (68-72)
Statistical estimates of rainfall traditionally employed GumbelвЂ™s
law. However, over the course of time it was realised that the
records of many weather stations did not comply with this law.
New calculation methods were put forward and regionally based
methods eventually established themselves. This paper presents
a new regional method for defining maximum rainfall for a given
return period, based on so-called L-moments, which is more accurate. This method has also developed processes for assessing
the heterogeneity of a given region and goodness of fit, and software has been produced for performing the calculations. It was
found that in the case of the river Francol, there was a matching fit
with the method of weighted positioning of the centre of gravity
of the sample in the L-asymmetry, L-Kurtosis plane.
380
HYDROLOGY
1989 An operational flash-flood forecasting chain applied to
the test cases of the EU project HYDROPTIMET
Taramasso A.C., Gabellani S. and Parodi A. Natural Hazards
and Earth System Science 2005 5/5 (703-710)
The application of a flash-flood prediction chain, developed by
CIMA, to some testcases for the Tanaro river basin in the framework of the EU project HYDROPTIMET is presented here. The
components of the CIMA chain are: forecast rainfall depths,
a stochastic downscaling procedure and a hydrological model.
Different meteorological Limited Area Models (LAMs) provide
the rainfall input to the hydrological component. The flashflood prediction chain is run both in a deterministic and in a
probabilistic configuration. The sensitivity of forecasting chain
performances to different LAMs providing rainfall forecasts is
discussed. The results of the application show how the probabilistic forecasting system can give, especially in the case of
convective events, a valuable contribution in addressing the uncertainty at different spatio-temporal scales involved in the flash
flood forecasting problem in small and medium basins with complex orography. В© 2005 Author(s). This work is licensed under
a Creative Commons License.
1990 The 8 and 9 September 2002 flash flood event in Fance:
A model intercomparison
Anquetin S., Yates E., Ducrocq V. et al. Natural Hazards and
Earth System Science 2005 5/5 (741-754)
Within the framework of the European Interreg IIIb Medocc
program, the HYDROPTIMET project aims at the optimization
of the hydrometeorological forecasting tools in the context of intense precipitation within complex topography. Therefore, some
meteorological forecast models and hydrological models were
tested on four Mediterranean flash-flood events. One of them
occured in France where the South-eastern ridge of the French
"Massif Central", the Gard region, experienced a devastating
flood on 8 and 9 September 2002. 24 people were killed during
this event and the economic damage was estimated at 1.2 billion
euros. To built the next generation of the hydrometeorological
forecast ing chain that will be able to capture such localized and
fast events and the resulting discharges, the forecasted rain fields
might be improved to be relevant for hydrological purposes. In
such context, this paper p resents the results of the evaluation
methodology proposed by Yates et al. (2005) that highlights the
relevant hydrological scales of a simulated rain field. Simulated
rain fields of 7 meteorological model runs concerning with the
French event are therefore evaluated for different accumulation
times. The dynamics of these models are either based on nonhydrostatic or hydrostatic equation systems. Moreover, these
models were run under different configurations (resolution, initial
conditions). The classical score analysis and the areal evaluation of the simulated rain fields are then performed in order to
put forward the main simulation characteristics that improve the
quantitative precipitation forecast. The conclusions draw some
reco mmendations on the value of the quantitative precipitation
forecasts ad way to use it for quantitative discharge forecasts
within mountainous areas. В© 2005 Author(s). This work is
licensed under a Creative Commons License.
1991 The behaviour of a hydrologic system under a Mediterranean climate using correlation and spectral analysis of the
water discharge and runoff. Case of three south Mediterranean basins: (Sebdou, Mouilah and Isser wadis - Tafna
- Algeria) (French) (Le comportement dвЂ™un système hydrologique en climat mВґediterranВґeen par lвЂ™analyse corrВґelatoire et
spectrale des dВґebits et des pluies. Cas de trois sous bassins
sud-MВґediterranВґeens: (oued Sebdou, Moulah et Isser - Tafna NW AlgВґerie))
Bouanani A., Baba Hamed K., Mania J. and Bensalah M. Revue
des Sciences de lвЂ™Eau 2005 18/2 (215-224)
The aim of this work was to show that correlation and spectral analyses can be used to understand the functioning of hydrological
systems. Accordingly, a study was carried out on three southern
Mediterranean basins: Sebdou; Mouilah and Isser; located in
the north western of Algeria (figure 1). Correlation and spectral
analyses of daily rainfall and discharge rates for one hydrological cycle were carried out.
Simple analysis Simple analysis
of rainfall showed that the correlogram s (figure 2) decreased
rapidly for the three basins, reaching a value of 0.2 within 1-
2 days. This result indicated that rainfall was a quasi-random
phenomenon. The variance density spectrum (figure 3) showed
that the rainfall distribution was not monotonous and presented a
"Leigh" signal structure. The simple analysis of discharge rates
indicated that the Sebdou system was different. The correlogram (figure 4a) decreased quicky, characterising independent
events without memory and with non-significant amounts of water. However, the Mouilah and Isser correlograms (figure 4 b,
c) decreased slowly. They represent important memory effects
with regulation of significant amounts of water. The spectral
band (figure 5) confirmed that the Sebdou system did not modify
the input information. The regulation time was about 5 d for
Sebdou, 21 and 43 d respectively for Mouilah and Isser. Cross
analysis The cor relograms (figure 6) show that the Mouilah and
Isser rivers have a great buffering ability. The Sebdou River was
characterised by a composite response of the surface flow and
an important groundwater flow. The amplitude function (figure
7) indicated that the Sebdou system had good inertia. The lag
time (figure 8) was 9, 2 and 5 days respectively for the Sebdou,
Mouilah and Isser rivers. The amplification and attenuation of
the input signal (figure 10) show that the Sebdou basin is the most
karstified system. The non-linearity of the relationship between
rainfall and discharge was expressed by the coherence coefficient
(figure 9), which was lower than 1.
1992 Peak discharge and time to peak scaling in urban runoff modeling (French) (Effet dвЂ™Вґechelle sur la simulation du
ruissellement en milieu urbain)
Kamal A. and Bennis S. Revue des Sciences de lвЂ™Eau 2005 18/2
(225-246)
It is possible to simulate the hydraulic functioning of a given
network either it is with a detailed "microscopic" model at the
street section scale or with a global "macroscopic" model which
generates total flow rated at the outlet of a basin. The microscopic model is useful when one is concerned with the hydraulic
performance of individual conduit sections and the precise locations of problematic areas within a network. Macroscopic
modeling is mainly useful when one is interested exclusively
by the exit flow rates of a basin. This may be the case in interceptor management where the flow rate is a parameter of the
global optimization procedure, within the framework of real time
management of regulators. In this case, detailed modeling of a
network is unnecessary. On the other hand, detailed modeling
requires that a voluminous data base be built and maintained,
implying expenditures exceeding the resources of small municipalities. The present work consists in elabora ting a systematic
method which allows one to substitute simplified hydraulic modeling for detailed modeling of a drainage network. The approach
is based on the analysis of the drainage parameters in an urban
environment. The non-dimensional groupings retained in this
analysis comprise the characteristics a of the basin, of the network and of rainfall. In order to provide a greater generality
to this approach, the authors applied the analysis to synthetic
networks and rainfalls covering a wide range of specific cases.
From a practical viewpoint, the objective was to link the peak f
low rates and the time to peak of the global model to those of the
detailed model of a basin. Two transfer functions have thus been
proposed in order to obtain the peak flow rate and the time to
peak of the detailed model as functions of the same parameters
provided by the global model. The parameters retained for the
transfer function are the density of the drainage network and
the rate of filling of the network. In order to im plement the
proposed method and perform the required hydraulic and hydrological simulations, the authors have used the SWMM program
(Storm Water Management Model). 180 simulations have thus
been completed, 15 for each type of network and for each type of
rainfall. For every combination, one computes the peak flow rate
and the time to peak as obtained by the global and detailed models
of the basin. The pr oposed multi-criterion analysis revealed that
the total discrepancy between simplified and detailed modeling
of a drainage network is very important. Within the range of the
assumed densities, the difference can be as great as 50%. This
discrepancy between global and detailed modeling is explained
by the storage capacity of the different types of networks. Indeed,
for a same given drained area, a network provides additional
storage with increasing length of the network and therefore with
increasing drainage density. On the basis of the above finding, a
HYDROLOGY
global model cannot replace a detailed model without the use of
required corrections for the computation of peak flow rates for a
given specific case. In order to resolve this difficulty, it is recommended to use the empirical models proposed herein to reduce the
discrepancy and thereby obtain the appropriate corrections. The
proposed method has been subjected to a validation program on
basin No.1 of the Verdun borough. Agreement between the flow
rates measured at the entrance of the RhВґeaume pumping station
and those simulated by the proposed method is very satisfactory.
The transformation models derived from the analysis allow for
the transition from a global model to a detailed one and provide
a significant improvement in optimized real time management of
drainage networks.
1993 Hydroclimatology of the Nile: Results from a regional
climate model
Mohamed Y.A., van den Hurk B.J.J.M., Savenije H.H.G. and
Bastiaanssen W.G.M. Hydrology and Earth System Sciences
2005 9/3 (263-278)
This paper presents the result of the regional coupled climatic
and hydrologic model of the Nile Basin. For the first time the
interaction between the climatic processes and the hydrological
processes on the land surface have been fully coupled. The hydrological model is driven by the rainfall and the energy available
for evaporation generated in the climate model, and the runoff
generated in the catchment is again routed over the wetlands
of the Nile to supply moisture for atmospheric feedback. The
results obtained are quite satisfactory given the extremely low
runoff coefficients in the catchment. The paper presents the validation results over the sub-basins: Blue Nile, White Nile, Atbara
river, the Sudd swamps, and the Main Nile for the period 1995
to 2000. Observational datasets were used to evaluate the model
results including radiation, precipitation, runoff and evaporation
data. The evaporation data were derived from satellite images
over a major part of the Upper Nile. Limitations in both the
observational data and the model are discussed. It is concluded
that the model provides a sound representation of the regional
water cycle over the Nile. The sources of atmospheric moisture
to the basin, and location of convergence/divergence fields could
be accurately illustrated. The model is used to describe the
regional water cycle in the Nile basin in terms of atmospheric
fluxes, land surface fluxes and land surface-climate feedbacks.
The monthly moisture recycling ratio (i.e. locally generated/total
precipitation) over the Nile varies between 8 and 14%, with an
annual mean of 11%, which implies that 89% of the Nile water
resources originates from outside the basin physical boundaries.
The monthly precipitation efficiency varies between 12 and 53%,
and the annual mean is 28%. The mean annual result of the Nile
regional water cycle is compared to that of the Amazon and the
Mississippi basins. В© 2005 Author(s). This work is licensed
under a Creative Commons License.
1994 Regional streamflow estimation by standard regional
dependence function approach
ВЁ
Altunkaynak A., Ozger
M. and SВёen Z. Journal of Hydraulic
Engineering 2005 131/11 (1001-1006)
The main purpose of this paper is to propose a standard regional
dependence function (SRDF) based on concepts of semivariogram and especially point cumulative semivariogram for regional
streamflow estimation. The SRDFs are obtained from available
spatial data and show regional dependence, which decreases with
distance from a given site. These functions present quantitatively the regional dependence of the streamflow phenomenon
recorded at irregular sites over a drainage basin and provide a
unique opportunity for the establishment of regional objective
estimation method based on weighed averages. The weightings
are obtained by means of the SRDF given the distance between
any two sites. The implementation of the proposed methodology
is presented for some streamflow records from the Lower and
Upper Mississippi River watershed in the United States. For the
application, the experimental SRDF forms are first obtained from
the available data, and these are then employed directly in the
regional estimation procedure. The study indicated that the use
of all the stations in a region for the estimation at any particular
station is rather naВЁД±ve because far away stations (more than 1,000
km away) are taken into consideration. The final conclusion
is that discharge at any particular station is better described as
381
a function of discharge at several (3-5) closest stations. The
reliability of the method is measured through the cross validation
procedure, and it is observed that the procedure yields streamflow predictions with less than 10% relative error. Journal of
Hydraulic Engineering В© ASCE.
1995 Magnification of flood disasters and its relation to regional precipitation and local human activities since the 1980s
in Xinjiang, northwestern China
Fengqing J., Cheng Z., Guijin M. et al. Natural Hazards 2005
36/3 (307-330)
Analyses of flood disasters were conducted using 1950-2001
data on the flood-damaged areas of cropland, the annual number
of flood disasters and the direct economic losses in Xinjiang.
There is an increasing trend in flood disasters in Xinjiang during
the second half of the 20th century, especially since the mid1980s. Results of a non-parametric Mann-Kendall test on the
cropland-flooded index time series revealed an abrupt change
in the mid-1980s. The reasons are discussed with respect to
changes in annual precipitation and regional human activities,
by correlating cropland-flooded area to annual precipitation and
three socio-economic parameters (population, cropland area and
GDP). The correlation coefficients between the flood-damaged
area and the annual precipitation during the periods 1961-1998
and 1987-1998 were substantially higher than during the period
of 1961-1986. The correlation coefficients between the flooddamaged area and the three human activity parameters, however,
were relatively high for the whole period of 1961-1998, but generally not significant for the 1961-1986 and 1987-1998 periods,
separately. These suggest that the occurrence of flood disasters could be mainly induced by local human activities before
the mid-1980s, and thereafter mainly by abnormal precipitation
in Xinjiang. Meteorological and hydrological records showed
that the number of heavy rainfall events and the frequency of
rainstorm flood disasters increased since the 1980s. In addition,
siltation of reservoirs and loss of flood control structures are
partly responsible for the increase of flood-damaged area. These
results suggest that the increasing trend in flood disasters in Xinjiang since the middle 1980s could be attributed, at least in part,
to an increasing trend in annual precipitation. В© Springer 2005.
1996 Hydrological cycle in the upper Mississippi River
basin: 20th century simulations by multiple GCMs
Takle E.S., Jha M. and Anderson C.J. Geophysical Research
Letters 2005 32/18 (1-5)
We used 20th century simulations by nine global climate models
(GCMs) to provide input for a streamflow model to simulate
baseline hydrologic conditions in the Upper Mississippi River
Basin (UMRB). Statistical tests revealed that streamflow data
produced by members of the GCM multi-model ensemble were
serially uncorrelated at all lags and formed unimodal distributions
and that GCM multimodel results may be used to assess annual
streamflow in the UMRB. Although all low-resolution GCMs
produced large differences from observations of streamflow and
hydrological components simulated by the streamflow model, the
nine-member ensemble performed quite well. Results of statistical tests indicate that, of all models used, the high-resolution
GCM - the only high-resolution model tested - gives simulated
streamflows much closer to observed values, despite the fact that
its low-resolution sister model has no advantage over the other
seven low-resolution models. Copyright 2005 by the American
Geophysical Union.
1997 Evaluation of the synthetic annual maximum storms
Saf B. Journal of Environmental Hydrology 2005 13/- (11p)
Long term historical records of hydrological information such as
rainfall and runoff data form the basis of planning and design
of major water resources projects. However, in most cases such
historical records are unavailable, and in situations where they are
available, the records are too short to have any statistically significant meaning. One approach that has been adopted to overcome
this difficulty is to generate long-term data synthetically. In this
study, the outcome of an attempt to generate synthetic rainfall
data is presented. The Monte Carlo method is used, which is an
experimental statistical method in generating samples for solving
some probability problems as old as probability theory itself. In
382
HYDROLOGY
this study, synthetic annual maximum storms distributed as Type1Extremal (or Gumbel) with random effective durations and specific time distribution for given population mean and variance are
generated using the method. Effective durations of the synthetic
annual maximum storms are related to the basin characteristics,
length (L) and harmonic slope (S) of the main course, by KirpichвЂ™s time of concentration relationship. After synthetic annual
maximum storms are generated, sample statistics and frequency
distributions of the generated annual maximum storms of random
effective durations are investigated. Eight well-known probability distribution models, (Normal (N), LogNormal with two and
three parameters (LN2 and LN3), Gumbel (GUM), LogGumbel
(LGUM), Gamma with two and three parameters (G2 and G3),
and LogPearson 3 (LP3), with moment and maximum likelihood
parameters are used for synthetic storm series by chi-square and
probability plot correlation goodness of fit tests. The results of
the study reveal that the probability distribution of the rainfall
input may even diverge from their parent (Type-I Extremal) distributions because of the sampling, and since the generated input
series is a mixture of rainfall events of variable durations.
1998 Generation mechanism of woodland runoff and sediment on Loess Plateau under hypo-rainfall - A case study of
artificial P. tabulaeformis and secondary natural P. dadidiana
stands (Chinese)
Pan C. and Shangguan Z. Chinese Journal of Applied Ecology
2005 16/9 (1597-1602)
Based on the long-term observation and from the viewpoints of
water balance and runoff-and sediment generation, this paper
studied the generation processes of runoff and sediment on two
typical woodlands, artificial P. tabulaeformis and secondary natural P. dadidiana, and uncultivated slope-land in Loess Plateau
under hyporainfall. The results showed that within the range of
5.0-50.0 mm rainfall, the total interception of canopy and litter
was 15.45%-56.80% for P. tabulaeformis and 20.56%-47.81% for
P. dadidiana, and decreased with increasing rainfall. Woodlands
had a higher soil water infiltration capacity than uncultivated
slope-land, especially in 0-20 cm soil layer. Both the two woodlands did not generate runoff under regular rainfall. Under the
assumed rainfall of 2.5 mm min-1 intensity and 30 min duration,
P. dadidiana stand did not produce runoff, but the runoff velocity
and sediment-carrying capacity of uncultivated slope-land were
23.5 times, and runoff shearing stress and energy were 8 times
as much as P. tabulaeformis stand. The runoff-and sediment
generation on P. tabulaeformis stand decreased by 87.6% and
99.4%, respectively, compared with those on uncultivated slopeland, which was well accorded with the average observed value
in runoff plots during 1988-2000. The theoretical analysis on the
generation mechanism of woodland runoff and sediment may
be effective to evaluate the benefits of forest in soil and water
conservation.
1999 Construction and verification of distributed rainfallrunoff model for forested watershed in alpine and gorge region (Chinese)
Liu J., Pei T., Wang A. and Yang H. Chinese Journal of Applied
Ecology 2005 16/9 (1638-1644)
Considering of the main hydrological characteristics in the upper
Zagunao River watershed of the upper reach of Minjiang River,
general hydrological models were selected to construct the distributed rainfall-runoff process model for the forested watershed
in typical alpine and gorge terrains. Calibration of too many
regional parameters was avoided to assure the transportability of
the models in similar watersheds. Two flow series of 1 000 hours
in 1999 and 2000 were simulated by using the distributed model.
The runoff hydrograph, accumulative runoff volume, peak discharge, and peak time showed good fittings with observed series. The simple structure and less empirical parameters gave
the distributed model the ability to simulate the rainfall-runoff
processes in similar watershed across scales, which provided the
basic approach to the hydrological scaling research.
2000 Application of wavelet transform to monthly runoff
time serial analysis in Zagunao watershed, the upper Minjiang River (Chinese)
Lin Y., Liu S., Li C. et al. Chinese Journal of Applied Ecology
2005 16/9 (1645-1649)
Runoff is an important component of regional water resources,
and its dynamics is to some extent an indicator of water resources
dynamics in a region. To know the runoff dynamics and water
resources in a region is essential for the sustainable utilization and
planning of water resources, and for the research on hydrological
response of vegetation change at watershed scale. To disclose
the water resources dynamics in Upper Minjiang River, one of
the large reaches of Yangze River in southwest China, this paper
analyzed the runoff dynamic features of Zagunao watershed, an
important watershed in Minjiang River basin. Multi-Resolution
Analysis (MRA) and periodicity analysis were conducted with
Dmey wavelet function on the monthly runoff data from 1962 to
2002 observed by Zagunao hydrological station, which provided
a data-based approximation on the evolution of monthly runoff in
Zagunao watershed. It was found that the runoff dynamics in Zagunao watershed was relatively stable during 1962-1978, despite
that this period was just in correspondence with the term of intensive deforestation activities in Upper Minjiang River basin. It was
also clear that the runofff in Zagunao watershed was increased
from 1986 to 1997, which was inconsistent with the commonly
accepted viewpoint that the runoff decreased with increasing
vegetation cover in forest watershed. However, the increasing
trend from 1986-1997 was consistent with the research results
in Yichang by Wang Wensheng and with the global warming
at global and continent scale, which meant that global climate
change plays a big role in runoff dynamics in Upper Minjiang
River. Periodicity analysis showed that the rich-short water periodicity at the scale of 10 years (120 months) and 5 years (60
months) was 3 and 7 times, respectively, which could provide invaluable information for the eco-hydrological function research
of forest landscape in Minjiang river basin and the sustainable
utilization of water resources. The results from the case study
highlighted that sometimes, it was very necessary to consider the
role of global climatic warming in disclosing the hydrological
response of land use/cover change at watershed scale, otherwise,
it would be difficult to explain some hydrological phenomena.
2001 Relationships between soil and water loss and landscape pattern on Loess Plateau (Chinese)
Suo A., Hong J., Lin Y. and Ge J. Chinese Journal of Applied
Ecology 2005 16/9 (1719-1723)
Based on the theories of detrended canonical correspondence
analysis (DCCA), 12 soil and water loss indices ("species") and
7 landscape indices ("environmental factors") were adopted to
quantitatively analyze the effects of landscape pattern on the soil
and water loss in Jinghe River basin on Loess Plateau. The results
showed that the first four DCCA axes were significantly correlated to agricultural land ratio, landscape diversity index, forest
land ratio, and landscape contagion index. The characteristics
of soil and water loss changed obviously with landscape pattern
gradient, e.g., Sanshuihe watershed with a forest cover larger than
65% and low landscape diversity had a big and stable runoff, but
small sediment and low river sand content. The runoff generation
coefficient and runoff depth as well as the sediment transport and
river sand content increased with the increasing agricultural land
ratio and landscape diversity and the decreasing forest land ratio.
As for Honghe watershed with a very low forest cover but high
agricultural land ratio (53.41%), and with a relatively high landscape diversity and complex landscape pattern, it had the highest
river sand content and the biggest sediment transport, and its
monthly runoff and sediment transport varied markedly. The soil
and water loss in the Upper-Huan, Down-Huan and Dongchuan
watersheds with smaller forest and agricultural land ratio and
relatively simple landscape pattern was smaller than that of the
watersheds with dominated agricultural land.
2002 Indoor imitation experimental study on driving factors
of rainfall-runoff process
Zhang S., Liu C., Xia J. et al. Science in China, Series D: Earth
Sciences 2005 48/3 (417-428)
The driving actions of rainfall-runoff process can be attributed
to two aspects. The first is the influence of precipitation process,
and the second is that of the ground pad. The research results
of 179 indoor experiments conducted to imitate rainfall-runoff
process indicate that both precipitation duration and intensity
play important roles in affecting confluence lag time, which is
HYDROLOGY
obviously inconsistent with the traditional hypotheses. The nonlinear relationship is of great significance to the confluence curve
especially when the precipitation duration is less than the total
confluence time or the precipitation intensity is small. Therefore
it can be concluded that the unit hydrograph (UH) can be applied
to rainfall-runoff process imitation in the humid areas in the south
China region. However, the UH application should be strictly
modified in accordance with precipitation conditions in the arid
and semiarid region of north China where the precipitation duration is short and the intensity is unstable. It will be hard to
get ideal imitation results if the UH is applied blindly without
considering specific conditions in the north China region. This
also explains the unsatisfactory imitation results caused by using
various hydrological models in the north China region. When
the precipitation duration is short, and the watershed has not
reached total watershed concentration, the characteristics of confluence change greatly, which reflects the actual situation in the
north China region. Therefore necessary nonlinear corrections
should be made when UH is applied. If the duration is longer
than the total confluence time and the balance between pondage
and discharge is stricken, the imitation research results will be
applicable to both rainfall-runoff relation with longer duration
in the south China region and the basic theoretical research on
runoff generation and concentration. On conditions of adequate
rainfall, peak discharge is in linear relationship with intensity, but
has nothing to do with the ground pad. There is a negative linear
relationship between intensity and time to peak. The amount of
pondage capacity in a catchment is in linear relationship with intensity and peak discharge, with obvious influence by the ground
pad status and interception, and it has nothing to do with the
position of interceptions. Copyright by Science in China Press
2005.
Channel hydraulics and sediment
transport
2003 Errors of kinematic wave and diffusion wave approximations for time-independent flows with infiltration and momentum exchange included
Singh V.P., Jain S.K. and Sherif M.M. Hydrological Processes
2005 19/9 (1771-1790)
Error equations for kinematic wave and diffusion wave approximations were derived for time-independent flows on infiltrating
planes and channels under one upstream boundary and two downstream boundary conditions: zero flow at the upstream boundary,
and critical flow depth and zero depth gradient at the downstream
boundary. These equations specify error in the flow hydrograph
as a function of space. The diffusion wave approximation was
found to be in excellent agreement with the dynamic wave approximation, with errors below 2% for values of KF (e.g. KF
7 5), where K is the kinematic wave number and F is the
Froude number. Even for small values of KF (e.g. KF = 2 5),
the errors were typically less than 3%. The accuracy of the diffusive approximation was greatly influenced by the downstream
boundary condition. For critical flow depth downstream boundary condition, the error of the kinematic wave approximation
was found to be less than 10% for KF 7 5 and greater than
20% for smaller values of KF. This error increased with strong
downstream boundary control. The analytical solution of the
diffusion wave approximation is adequate only for small values
of K. Copyright В© 2005 John Wiley & Sons, Ltd.
2004 A simple method to include vertical resolution in a
river model, and results from an implementation
Jakobsen F., Olesen K.W. and Madsen M. Nordic Hydrology
2005 36/2 (163-174)
A simple method to include vertical resolution in a one-dimensional river model is outlined. The equations on which the
method is based are the width-averaged continuity, momentum
and transport equations. Some details are given on how to formulate the bed friction in a river model with vertical resolution.
The equations are transformed to be in sigma coordinates. The
numerical techniques, which make maximum use of an already
implemented numerical solution technique in an existing river
383
model, are described. The method is used to implement vertical
resolution in the existing river model, MIKE 11. The implementation is tested on the following cases: logarithmic velocity
profile, wind driven velocity profile, rapid accelerated flow, lock
exchange and finally wind-forced entrainment. All test cases
showed good agreement. В© IWA Publishing 2005.
2005 Changes in hydrologic regime by dams
Magilligan F.J. and Nislow K.H. Geomorphology 2005 71/1-2
(61-78)
Dams have major impacts on river hydrology, primarily through
changes in the timing, magnitude, and frequency of low and high
flows, ultimately producing a hydrologic regime differing significantly from the pre-impoundment natural flow regime. This paper presents the analysis of pre- and post-dam hydrologic changes
from dams that cover the spectrum of hydrologic and climatic
regimes across the United States. Our overall goals are to document the type, magnitude, and direction of hydrologic shifts because of impoundment. Using the entire database for the National
Inventory of Dams (NID) for dams possessing longstanding U.S.
Geological Survey (USGS) gages downstream, we identified 21
gage stations that met length-of-record criteria encompassing an
array of types of dams and spanning four orders of magnitude in
contributing watershed area. To assess hydrologic changes associated with dams, we applied a hydrologic model, the Indicators
of Hydrologic Alteration (IHA), supplemented with orientation
statistics for certain hydrograph parameters. Dams had significant impacts on the entire range of hydrologic characteristics
measured by IHA. For many characteristics, the direction and
significance of effects were highly consistent across the 21 sites.
The most significant changes across these sites occurred in minimum and maximum flows over different durations. For low flows,
the 1-day through 90-day minimum flows increased significantly
following impoundment. The 1-day through 7-day maximum
flows decreased significantly across the sites. At monthly scales,
mean flows in April and May tend to decline while mean flows in
August and September increase. Other significant adjustments
included changes in annual hydrograph conditions, primarily in
the number of hydrograph reversals that has generally increased
for almost all sites following impoundment. The number of high
pulses has increased following impoundment but the average
length declines. The mean rate of hydrograph rise and fall has
declined significantly. These results indicate that the major pulse
of dam construction during the previous century has modified
hydrologic regimes on a nationwide scale, for large and small
rivers. В© 2005 Elsevier B.V. All rights reserved.
2006 Uncertainty in predicting riverbed erosion caused by
urban stormwater discharge
Daebel H. and Gujer W. Water Science and Technology 2005
52/5 (77-85)
Ecologically based criteria require an integrated modeling approach. Due to the complexity of the system, the stochastic
nature of loads, and the model abstractions, many uncertainties
are involved. In this study, a simple integrated model is applied,
which Swiss engineers employ to assess the impact of urban
stormwater discharges on riverbed stability. In the course of a
case study, an uncertainty analysis is carried out focusing on
parameter uncertainties. The underlying context of the uncertainties is evaluated, and a variance-based sensitivity analysis is
presented estimating the local uncertainty contribution of each
parameter. The results reveal that the largest contributions stem
from the model components describing the natural system. An
experimental design is proposed that manages to reduce the output uncertainty significantly. Finally, we discuss the benefits of
following the proposed procedure. В© IWA Publishing 2005.
2007 Intergranular flow velocity through salmonid redds:
Sensitivity to fines infiltration from low intensity sediment
transport events
Zimmermann A.E. and Lapointe M. River Research and Applications 2005 21/8 (865-881)
This paper presents results from a novel technique allowing continuous monitoring through multiple storm events of interstitial
flow in salmonid redds. Previous studies have shown that longterm increases in fine sediment inputs into rivers can silt up
spawning beds, reduce intergravel flow and threaten egg survival.
384
HYDROLOGY
Not enough is known, however, about the temporal and spatial
scales of the physical processes affecting spawning habitat. The
short-term sensitivity of intergravel flow through salmon nests
to low-intensity sediment transport events has not been documented. Furthermore, it is unclear if the egg pocket flow vital to
incubation is principally controlled by the hydraulic conductivity
of the redd patch or by that, generally lower, of the ambient riffle
substrate. The purpose of this study was to determine if individual runoff events could affect intergravel flow in salmon nests and
to investigate the sensitivity of interstitial flow to the fines content
and conductivity of the redd patch. During the summer and autumn of 2001, a new intergravel velocity sensor based on the hot
wire principle made it possible to continuously monitor, over five
months, interstitial velocities in artificial redds in four tributaries
of the Cascapedia River, Quebec. Fifteen low and moderate intensity runoff events (up to 50% bankfull) were monitored. Data
were obtained for each storm on suspended sediment transport
as well as sand infiltration rates in sediment collectors emplaced
in redd zones. It was found that redd interstitial velocities were
reduced whenever a runoff event deposited more than 7 kg/m2 of
sands in infiltration traps. In addition, redd interstitial velocities
were reduced four out of the five times that the event-integrated
suspended sediment dose exceeded 7 mg1-1 day (dose is defined
as the area under the concentration time curve). In the study conditions, where ambient riffle sediment has relatively moderate
permeability and localized groundwater upwelling is negligible,
our data suggest that significant intergravel flow (0.1-0.6mm/s)
can be triggered through 2m long redd patches, in response to
the redd-scale water surface gradient and the relatively higher
conductivity of the redd patch, after spawner activity. Copyright
В© 2005 John Wiley & Sons, Ltd.
2008 Streambed sediment composition and deposition in a
forested stream: Spatial and temporal analysis
St- Hilaire A., Caissie D., Cunjak R.A. and Bourgeois G. River
Research and Applications 2005 21/8 (883-898)
Assessment of fish habitat quality often includes the measurement of substrate composition and fine sediment deposition in
streams. The natural spatial (localized, inter-reach) and temporal (event-specific, seasonal, annual) variability of both sediment
deposition and streambed composition were investigated in Catamaran Brook (New Brunswick, Canada). A grab-type sampler
(i.e. scoop) and Whitlock-Vibert boxes were used to investigate
grain size distribution of streambed material and deposition of
fine sediments over time. Results showed that the scoop sampler
was a good method to quantify intra-site and inter-site grain-size
distribution, especially as it relates to the streambed composition and changes thereof. In Catamaran Brook, scoop samples
showed that gravel constituted the highest percentage of the total
dry weight wit

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