Geomorphology 119 (2010) 9–22
Contents lists available at ScienceDirect
Geomorphology
j o u r n a l h o m e p a g e : w w w. e l s e v i e r. c o m / l o c a t e / g e o m o r p h
Human-driven coastline changes in the Adra River deltaic system, southeast Spain
Antonio Jabaloy-Sánchez a,⁎, Francisco José Lobo b, Antonio Azor a, Patricia Bárcenas c,
Luis Miguel Fernández-Salas d, Víctor Díaz del Río d, José Vicente Pérez-Peña a
a
Departamento de Geodinámica, Facultad de Ciencias, Universidad de Granada, Avenida de Fuentenueva s/n, 18002 Granada, Spain
CSIC—Instituto Andaluz de Ciencias de la Tierra, Facultad de Ciencias, Avenida de Fuentenueva s/n, 18002 Granada, Spain
Departamento de Análisis Matemático, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos s/n, 29080. Málaga, Spain
d
Instituto Español de Oceanografía, Centro Oceanográfico de Málaga, Puerto Pesquero s/n, Apartado 285, 29640 Fuengirola, Spain
b
c
a r t i c l e
i n f o
Article history:
Received 24 June 2009
Received in revised form 3 February 2010
Accepted 7 February 2010
Available online 19 February 2010
Keywords:
Delta
Coastline changes
Damming
River deviation
Bathymetry
GIS
a b s t r a c t
The recent evolution of the Adra River delta in southeastern Spain has been reconstructed from historical
maps, aerial photographs, and submarine multibeam bathymetric data. We have distinguished three main
evolutionary stages whose development took place as a direct response to the main anthropic and natural
influences on the river system. The first stage (4000 BC to 1872 AD) represents the natural behavior of the
deltaic system with negligible anthropic influence. This long stage is characterized by coastline advance with
the formation of a small asymmetric triangular delta in the natural river mouth and a typical prodeltaic
deposit. In contrast, the second and third stages are characterized by anthropic interventions in the
catchment and the river mouth, which heavily modified the natural dynamics of the deltaic system. The
second stage (1872 AD to 1972 AD) coincided with damming of the natural river channel very close to its
mouth and the construction of two successive artificial channels to deviate the river flow. The coastal
dynamics changed during this second stage with erosion of the original delta and the formation of a new,
asymmetrical delta at the mouth of the artificial channels. This younger eastern delta comprises two
infralittoral wedges in the submarine realm, which recorded changes of lateral redistribution processes and
enhanced influence of energetic events and can only be explained if the sediment supply from the river
source was reduced during this period. The third stage (1972 AD to present-day) started with the damming
of the trunk river in the central sector of the catchment, thus drastically reducing sediment flow to the
coastal realm and triggering general erosion and coastline retreat.
© 2010 Elsevier B.V. All rights reserved.
1. Introduction
Coastal processes occur at very high rates as compared to other
geological processes, thus enabling people to observe changes (cliff
retreat, beach erosion, sand-dune growth, etc.) at human-lifespan
scales. The fast evolution of coastal settings necessarily translates into
extreme fragility in these environments and great vulnerability to
human-driven processes such as river management, land-use changes,
beach reconstructions, and harbor enlargements. Nevertheless, geological processes such as coastal-sediment supply, tectonic uplift and sealevel changes also play an important role in coastal evolution, especially
on long time-scales (Ka to Ma).
Coastal geomorphology is a very useful tool for evaluating whether
a given coastline is advancing or retreating. At geological time-scales,
stratigraphic and geomorphic data can be used to reconstruct past
coastlines and to decipher surface uplift histories (e.g., Braga et al.,
2003; Maurya et al., 2008). At short-term time-scales (i.e., decadal to
⁎ Corresponding author. Tel.: +34 958 243365; fax: +34 958 248527.
E-mail address: [email protected] (A. Jabaloy-Sánchez).
0169-555X/$ – see front matter © 2010 Elsevier B.V. All rights reserved.
doi:10.1016/j.geomorph.2010.02.004
millennial), a combination of geological, historical, and instrumental
data is usually the best approach to study coastline evolution (e.g.,
Dornbusch et al., 2008; Kaya et al., 2008).
Within coastal realms, deltaic systems are particularly sensitive to
coastline changes as they tend to be a location of choice for numerous
communities and have high ecological, economic, and social importance. Consequently, deltaic systems have been amply used to
document short-term natural- and human-driven processes responsible for coastline changes (e.g., Fan et al., 2006; Xeidakis et al., 2007;
El Banna and Frihy, 2009; Sabatier et al., 2009; Simeoni and Corbau,
2009). Among the former, the development of deltaic units may be
influenced by short-term climate change inducing precipitation
changes, rapid sea-level changes, autocyclical processes such as
channel avulsion and delta-lobe switching, and tectonism (Mateo
and Siringan, 2007). Furthermore, several anthropogenic activities
can also significantly impact and control the morphology and
evolutionary behavior of the different components of fluvio-deltaic
systems (Correggiari et al., 2005). Anthropogenic activities leading to
considerable coastline changes include channelization/channel deviation, dredging, damming, and deforestation, among others (Fan et al.,
2006; Simeoni and Corbau, 2009). However, the response of deltaic
10
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
systems to natural or human-induced changes is mainly controlled by
changes in the sediment supply reaching the coastal domain (Mateo
and Siringan, 2007). Therefore, the comprehension of coastline
evolution and related changes in deltaic systems is necessarily
based on a reasonably good knowledge of the leading triggering
processes, whether natural or human-induced.
Many deltaic systems in the Mediterranean region are tectonically controlled (Longhitano and Colella, 2007). A nice example of
this influence is provided by the drainage basins of the southern
Iberian Peninsula flowing into the Alboran Sea, where the proximity
of the Betic Mountains to the coast dictates marked abrupt relief in
most of the catchments. Another important factor that influences the
type and quantity of sediment supply in the region is the prevalence
of a typical Mediterranean climate with contrasting seasonal conditions. As a consequence of the physiographic and climatic controls,
the hydrological regime of many of those Mediterranean rivers is
torrential (Liquete et al., 2005). Thus, some deltaic depositional
systems of the Alboran Sea show distinctive depositional patterns
that bear more resemblance to fan deltas than to typical river
deltas due to the dominance of rapid sedimentation and limited
lateral redistribution (Lobo et al., 2006). Therefore, they can be
regarded as good candidates for comparing the relative influences
of short-term recent natural processes and changes related to
human activities.
This paper aims to reconstruct recent coastal and shallow-marine
changes of a sector of the Betic Cordillera in Southern Spain made up
of a delta at the mouth of a medium-sized catchment draining a highly
mountainous region. River management (dam building and channel
deviation) seems to have controlled the recent coastline evolution
and the activity of the submerged parts of the delta, with subsequent
modification of the main depositional/erosional areas. We also intend
to quantify these changes by using historic maps, aerial photographs,
and submarine bathymetric data.
2. Geological setting
The Adra River, in the eastern sector of the Betic Cordillera in SE
Spain, drains to the Mediterranean Sea (Fig. 1A). Its catchment
extends through part of the southern slope of the Sierra Nevada, the
western slope of the Sierra de Gádor, and the eastern slope of the
Sierra de la Contraviesa (Fig. 1B). From a geological point of view, this
catchment is located in the Internal Zone of the Betic Cordillera, which
is made up of schists, phyllites, and marbles of Palaeozoic to Triassic
age in this area. The central part of the catchment and the mouth of
the main river expose Neogene–Quaternary sediments deposited on a
metamorphic basement. These sediments are dominantly poorly
consolidated conglomerates and sands related to past alluvial fans and
river systems. Structurally, the sierras are antiformal ridges, that is,
they correspond to km-scale E–W orientated antiforms that have
developed since the latemost Miocene. The valleys between the
sierras generally correspond to synforms, where Neogene–Quaternary basins formed. Moreover, some of the mountain fronts are faultbounded, with right-lateral strike-slip faults dominating the southern
Sierra Nevada mountain front and normal faults dominating the
western Sierra de Gádor mountain front (e.g., Martínez-Martínez et
al., 2006). These fault systems show evidence of activity during the
Quaternary.
3. Geomorphology of the Adra River catchment
The Adra River catchment has an area of 744 km2 with a maximum
N–S length of 39 km and an E–W width of 21 km, forming an irregular
pentagonal polygon (Fig. 1A). The northern divide of the catchment
corresponds to the crest-line of the Sierra Nevada, reaching maximum
elevations of 2786 m at the San Juan peak and 2611 m at the Chullo
peak (Fig. 1B). The eastern and western divides have maximum
elevations of around 2000 m at 10–20 km from the Mediterranean
Sea. The Adra River basin is characterized by steep topography with a
relatively straight hypsometric curve, indicative of a moderately
dissected landscape (Fig. 1C). The trunk river in the Adra catchment
features a typical concave-shaped longitudinal profile with a steep
(9.5% average slope) upper reach in the southern Sierra Nevada and a
shallow (1.85% average slope) middle-to-lower reach (Fig. 2). The
main tributaries draining the eastern termination of the Sierra de la
Contraviesa, namely the Rambla de Cojáyar and Rambla de Turón
(Fig. 1B), show quite rectilinear profiles with maximal slopes of 4.9%
and 6.8%, respectively (Fig. 2). The main tributary draining the
western Sierra de Gádor is the Chico River (Fig. 1B), which joins the
Adra River very close to its mouth. The longitudinal profile of the
Chico river shows a sharp step near its head (Fig. 2), probably related
to a knick-point in the most recent headward incision. The higher
slopes in this river are close to 16%, whereas the lower ones are
around 2.4% near its junction with the Adra River (Fig. 2).
Fluvial sediment discharges of several Mediterranean river systems
in southern Spain have been estimated by empirical methods based on
morphometric, climatic and discharge data (Senciales-González and
Malvárez, 2003; Liquete et al., 2005). Most rivers in this region have
discharge only during storms, while some others dry during summer
months. This is not the case of the Adra River, which is one of the scarce
rivers in this region with water all over the year, averaging a discharge
of 1.0 m3 s− 1. Accordingly, the estimated mean sediment load of the
Adra River system is one of the highest for southern Spain rivers
(4.8 kg s− 1, Liquete et al., 2005). The resulting mean sediment yield for
the Adra River system is 201.4 t km− 2 year− 1.
4. Climate
The Adra River catchment extends from the coastline to the
highest areas of the Sierra Nevada and Sierra de Gádor. The lowelevation sectors of the catchment around the coastline have a semiarid Mediterranean climate with an average annual rainfall of 200 mm
for the period 1971 AD to 2000 AD. This rainfall is distributed
throughout the year except for the summer (especially July and
August), which is usually very dry. A mountainous Mediterranean
climate reigns in the high sectors of the catchment, with an average
annual rainfall ranging from 400 to 700 mm. Rainfall distribution is
similar to that of the low-elevation sectors. Storms particularly affect
the Adra River drainage basin during the fall. Historical floods were
caused by fall storms, the last of which took place in October 19 of
1973 AD, when rainfall over a 24-hour period reached 250 mm in
some sectors.
Tidal oscillations are small in Mediterranean settings, usually not
exceeding 1 m high. As for wave data, predictions at open sea
conditions made by means of numerical models generated by the
“Instituto Nacional de Meteorología” (the so-called Wana model) are
available with an average resolution of 15 km. These estimates must
be used with caution at shallow-water conditions. In the area at study
here, three Wana points have been considered (Wana 2023013,
2024013 and 2025013), showing a clear prevalence of two wave
approaching directions: East and West–Southwest (Fig. 3). Easterly
waves are slightly more frequent than westerly waves. Most waves
are below 1.5 m high, with the West–Southwest direction being
slightly more energetic than the easterly one.
Past climates—especially the rainfall input—in southern Spain
have been reconstructed back to 1500 AD by numerical analysis
of available pre-instrumental and instrumental records (Rodrigo
et al., 1999, 2000). Apart from the present-day global-warming
trend, the most outstanding climatic event on a worldwide scale
over the past 500 years was the cold episode known as the Little
Ice Age (LIA), which involved a significant advance of glaciers in
mountainous regions (e.g., González Trueba et al., 2008). The rainfall reconstruction for the period suggests considerable fluctuation,
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
11
Fig. 1. A: Location of the Adra River catchment in the Iberian Peninsula. B: Sketch of the drainage network of the Adra River catchment. C: Hypsometric curve of the Adra River catchment.
with alternating dry and wet periods on centennial, decadal, and
inter-annual scales (Rodrigo et al., 1999). The long-scale periods
are as follows: a) 1501 AD to 1589 AD dry, b) 1590 AD to 1649 AD
wet, c) 1650 AD to 1775 AD dry, d) 1776 AD to 1937 AD wet, and
e) 1938 AD to 1997 AD dry (Rodrigo et al., 2000). According to these
data, the LIA event in southern Spain reached its maximum intensity between 1590 AD and 1650 AD, with wetter conditions
compared to average rainfall. In contrast, dry periods seem to coincide with warm temperatures.
5. Anthropic interventions in the Adra River system
The first human settlements of the Adra River catchment seem to
have started in the Neolithic period (around the 7th millennium BC).
12
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
Fig. 2. Longitudinal profiles of the main streams in the Adra River catchment. For location, see Fig. 1.
The Phoenician colonization of the western Mediterranean area
around the 8th century BC, included the foundation of Abdera at the
mouth of the Adra River (near the present-day location of the Adra
village) (i.e. Aubet-Semmler, 2002). Human presence was constant
from this moment on until the 16th century AD, but then wars,
deportations, pirate incursions, and slave trading significantly
depopulated the area. Only at the end of the 18th century AD did
the area begin to increase in population and economic activity with
the construction of sugar factories, as well as with lead mining and
foundries in the 19th century AD. Forests in this region were heavily
cut back as a consequence of these economic activities. Maps of forest
distribution were a common document of work for the Spanish Army
and Government in the 18th century AD. These maps recorded a
population of 500,000 Holm oaks in the Sierra de Gádor and
surrounding areas and around 300,000 Holm oaks in the central and
eastern Sierra Nevada (Gómez-Cruz, 1991). Most of the trees
disappeared during the first half of the 19th century AD, mainly for
the maintenance of foundries. Deforestation was accompanied by
frequent floods in the mouth of the catchment, i.e. in the Adra River
delta. During the 19th century AD, at least 15 great floods occurred in
the delta (Jabaloy-Sánchez, 1984; Guerrero-Montero, 2005), and the
Spanish Government ordered the artificial diversion of the natural
waterway and the building of a dam near the mouth of the river. The
main target of these works was to prevent floods in the natural valley,
to convert it into cultivated lands and divert the flow of water
eastwards to an area scarcely populated.
The waterway diversion lasted from 1866 AD to 1873 AD, (CuéllarVillar, 2006) and consisted in two connected works. The first one was
the construction of a 450 m-long ESE–WNW oriented earth dam that
crossed completely the natural valley and interrupted the natural
waterway; the second one was the excavation of a NW–SE oriented
channel carved in the Pliocene conglomerates of the eastern side of
the natural valley. This artificial channel was around 1 km long and
50 m wide, with steep walls ranging from 40 m high in the NW to 5 m
high to the SE end. At the end of the artificial channel, two small
1700 m-long earth levees were built with the same NW–SE trend,
serving as a prolongation of the carved waterway.
Despite this first diversion, during the 20th century, two major
floods destroyed the earth dam in the natural channel and damaged
the delta area. The first major flood occurred in 1910 AD and led to a
new artificial diversion of the river to its present-day location. The dam
in the natural channel was reinforced and the two NW–SE oriented
small levees were abandoned, building new and higher levees with a
NNW–SSE trend and around 1.5 km long.
The second major flood occurred in October 19th 1973 AD and led
to the construction of the Benínar dam in the middle course of the
river. This dam is located 20.8 km northwards of the mouth of the
river at an altitude of 363 m in a gorge excavated in carbonate rocks. It
is a clay-cored earth dam 300 m long and 87 m high. Its capacity is
68.3 hm3, regulating around 70% of the basin area.
Other major anthropic interventions have been the building of the
harbor in the year 1911 AD and a 7 km-long breakwater along the
coast of the deltaic system in the year 2000 AD in order to stop the
erosion.
6. Methodology
6.1. Historical coastline evolution
Hoffmann (1987) made a reconstruction of the evolution of the
coastlines in the Adra River delta from 4000 BC to 1895 AD. The main
data in Hoffmann (1987) come from 31 boreholes drilled in the delta
area, as well as from the study of archeological data (Phoenician and
Roman constructions and ceramic distribution) and old maps. Several
of the boreholes were located near ancient or present-day lagoons,
reaching peat levels that were dated by radiocarbon methods.
Radiocarbon ages enabled Hoffmann (1987) to determine a deposition rate of in the lagoons of 0.2 m/kyr. Boreholes in the river channel
revealed stratigraphic columns with several meters of fluvial deposits
covering marls and sands with mollusk shells (Cerastoderma edule)
typical of estuarine environments (Hoffmann, 1987). The archeological data studied by Hoffmann (1987) include several Phoenician and
Roman ceramic pieces found within the boreholes, as well as Roman
Garum factories built at the coastline. Old maps used by Hoffmann
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
13
Fig. 3. Data of wave trend and height in the three Wana points located in the vicinity of the Adra River deltaic system. A: Location of the points; B: Wave frequency, height and trend.
(1987) include several historical maps from the Museo Naval of
Madrid and the Servicio Cartográfico del Ejército from the years
1550 AD, 1759 AD, 1784 AD, and 1786 AD.
With all the aforementioned data, Hoffmann (1987) reconstructed
the coastlines at 800 BC (the moment of the Phoenician colonization),
1500 AD, 1877 AD, and 1895 AD, resulting in an average coastline
advancing rate of 60 m/kyr. By using this rate, Hoffmann (1987)
estimated a possible location of the coastline at 4000 BC, when the
estuarine media reached its maximum extension.
6.2. Geo-referenciation of historical maps
The analysis of historical maps using Geographic Information
Systems (GIS) is a very useful tool, since maps often contain information
that is not retained by any other written source. Thus, maps can
constitute the only way to analyze physical features that have been
strongly modified or erased by modern development. Nevertheless, the
degree of accuracy of historical maps can be a handicap, because they are
very influenced by the technology and scientific understanding
available at the time of their creation (Rumsey and Williams, 2002).
Thus, it is almost impossible to perfectly align an old map to modern
coordinate systems, because mapping methods before the age of aerial
photography, most of the times represented scale, angle, distance and
orientation very imprecisely. However, the value of the historical
information in paper maps compensates the residual error in their georeferenced versions (Rumsey and Williams, 2002).
To analyze the information contained in historical maps, we have
scanned and geo-referenced them. The geo-referenciation process
implies that selected control points on the original maps must be
aligned with their actual geographical location, either by assigning
geographical coordinates to each point or by linking each point to its
equivalent on a modern, accurate digital map. These links between
historical maps and real locations are used to warp the original raster
map into the chosen map projection, through the application of a
mathematical algorithm. This mathematical algorithm is a polynomial
transformation and a least squares fitting applied to control points. A
first order polynomial transformation is used when the raster only has
to be re-scaled and rotated; if the raster dataset must be bent or
curved, a second- or third-order polynomial transformation must be
used. This process is known as “rubber sheeting” (Saalfeld, 1985;
Tobler, 1994). Once the raster dataset is adjusted to the chosen
coordinate system, the residual errors related to the difference in
location of control points in the old map and their real location is
computed. The total error is computed by taking the root mean square
(RMS) sum of all the residuals. This value describes the consistency of
the polynomial transformation performed.
In this work, we have used the nautical chart of Adra and its
anchorage made by Francisco Coello, which corresponds to the coastline
at 1855 AD (Hoffmann, 1987; Paracuellos-Rodríguez, 2006). We have
also used a second nautical chart, published in 1876 AD by the Dirección
de Hidrografía and headed by José Montojo y Salcedo, whose surveys
and data collection were carried out in 1872 AD. The nautical chart of
Coello has been geo-referenced with the aid of ArcGIS software. We
have used a total of 39 control points regularly spaced through the UTM
grid of the map, having applied a second order polynomial transformation to adjust it. The RMS error obtained is 11.5 m.
The nautical chart of Montojo y Salcedo (1876) contains
information of coastline morphology and bathymetry. This nautical
chart was used during ≈90 years in the Spanish coasts, with several
editions published during the 19th and 20th centuries AD. We have
used two different editions in order to check the data. The first edition
is the original one from 1876 AD, kindly provided by the Instituto de
Cartografía de Andalucía from the Consejería de Obras Públicas of
Andalucía. The second edition is one of the last editions, published in
14
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
the 1940s. This version has the geographical coordinates referred to
the Greenwich meridian, having been kindly provided by the
Biblioteca de Andalucía. The two editions depict the same coastline.
In order to georeference this map we have used the most modern
edition, with a total of 21 control points regularly spaced trough the
geographical grid and some other control points in those features that
have been remained in the same place since the 19th century AD. We
have selected a third polynomial transformation to georeference this
historical map, yielding a RMS error of 237.3 m.
6.3. Geo-referenciation of aerial photographs
For the determination of the coastline during the second half of the
20th century, we have used photogrammetric series of aerial
photographs made by the Spanish Government (1956 to 1957 AD
and 1977 AD) and the Regional Government of Andalucía (1984 AD,
2002 AD, and 2004 AD).
The aerial photographs of 2002 AD and 2004 AD were obtained in
photogrammetric flights for the entire Andalucía region, being
planimetrically corrected (orthophotographs). The flight of 2004 AD
has an associated digital elevation model (DEM) with 10 m of pixel
resolution. The photographs of 1957–1957 AD, 1977 AD and 1984 AD
are not orthophotographs, having therefore image distortions due to
camera tilt, terrain topography, atmosphere, etc. These photographs
were rectified with the aid of the 10 m DEM to convert them in
orthophotographs. The coastlines were digitalized from the orthophotographs and analyzed with the aid of the Digital Shoreline Analysis
System (DSAS) tool (Thieler et al., 2009). This tool allows computing the
rate-of-change statistics for a time series of shoreline vector data.
6.4. Historical and present-day bathymetric data
The historical bathymetric data were obtained from the nautical
chart of Montojo y Salcedo (1876). These data are of course very
imprecise if compared with modern bathymetric data. Moreover, an
additional error is caused by the geo-referencing process. Nevertheless, these data are the only way to know the historical offshore
morphology. To reconstruct the morphology of the shallow seafloor at
the 19th century AD we have built a DEM by using an irregular
triangulation network (TIN). Despite being not very precise, this
model gives information of the general trends of the offshore
morphology, i.e., where the deeper and shallower areas were located.
The present-day shallow seafloor has been studied by swath
bathymetric data collected with a SIMRAD EM3000D System
operating at a frequency of 300 kHz during the year 2002 AD. The
EM3000D echosounder generates 254 beams (1.5°×1.5° wide, 0.9°
spacing) that include bathymetric information in a band with a width
ten times the water depth at a maximum ping rate of 25 Hz. The raw
data were post-processed with the Neptune® software, generating a
grid with 5 × 5 m resolution.
The two bathymetric datasets were compared to evaluate volumetric changes with the aid of ArcGIS software through a cut–fill process.
We have considered only two coastlines, namely those at 1877 and
2002 AD. We have not considered the supratidal volume of sediments
because of the very low topography of the deltaic area, which thus
would produce only very small variations in volume estimations. For
instance, a 5 m-thick sediment layer covering the whole supratidal delta
would increase the volume in 3.3 × 106 m3.
7. Coastline changes and delta formation
The Adra River outlet started to form as an estuary during the
Holocene eustatic maximum around 4000 BC (Hoffmann, 1987). The
coastline advanced seawards from this moment on, finally forming a
delta. Thus, successive coastlines dated at 4000 BC, 800 BC, 1500 AD,
1855 AD, and 1873 AD have been considered (Fig. 4A and B). The first
two coastline reconstructions are not very accurate, especially the one
dated at 4000 BC, which has been taken here as the starting point of
delta formation. Assuming these reconstructions to be true, this 3200year-long stage of estuary infill is characterized by a coastline advance
of 1800 m at an average rate of 0.56 m/year.
The coastline reconstruction at around 1500 AD is well documented with historical references to a narrow coastal plain and several
swamps at that time (Hoffmann, 1987; Paracuellos-Rodríguez, 2006).
Therefore, this 2300-year-long stage recorded the formation of a
coastal plain ≈7.4 km long in an east–west direction and 200–400 m
wide in a north–south direction (Fig. 4A). The average rate of coastline
advance for this stage is 0.09–0.17 m/year. The nautical chart drawn
up by Francisco Coello for Adra and its anchorage depicts the coastline
at 1855 AD (Hoffmann, 1987; Paracuellos-Rodríguez, 2006). Between
1500 AD and 1855 AD, an asymmetrical triangular delta formed,
increasing the area of the former coastal plain by 1,340,000 m2 at an
average coastline advance of 0.56 m/year.
The second half of the 19th century AD marks the beginning of
strong human influence on the Adra River through the damming and
diversion of the natural channel (see Section 5). Nautical chart
number III (Motril, Granada) by Montojo y Salcedo (1876) depicts the
natural channel and the first artificial channel, as well as the presence
of a very asymmetric delta associated with the natural river mouth
(Figs. 4B, 5 and 6). Between 1855 AD and 1873 AD, the delta increased
in area by 2,000,000 m2, indicating an average rate of coastline
advance of 16.0 m/year.
In 1910 AD, a large flood destroyed the dam and led to a new
artificial diversion of the river to its present-day position (Figs. 4C
and 7). An oblique aerial photograph taken in 1927 AD (Adra town
archives, in Paracuellos-Rodríguez, 2006) and also the cartography of
the German Army made during the period of 1940–1944 AD, but based
on older data (Spanien 1:50,000. Deustche Heereskarte, published by
Junta de Andalucía, 2007), illustrate the existence of two deltas: (i) the
remains of the ancient delta in the natural river mouth, with an
undulated coastline due to erosion, and (ii) a new delta that expanded
eastwards in response to the artificial channels (Fig. 4C). This same
situation with two deltas is confirmed by vertical aerial photographs
taken in 1956 AD (Fig. 4D and E). Consequently, between 1873 AD and
1956 AD, the old natural delta diminished in area, whereas the new
eastern delta grew to a total area of around 3,060,000 m2. The eastern
delta was also asymmetrical (Fig. 4D and E) due to the dominant
easterly longshore drift in this area. The coastline length along the new
delta was 4.2 km, whereas its width perpendicular to the coastline
ranged from 700 to 1000 m, indicating rates of coastline advance close
to 10 m/year.
After 1973 AD, the Benínar dam was built in the middle reach of
the Adra river (see Section 5), thus precluding significant sediment
transport to the river mouth. To measure dam influence on the
coastline, we have used the vertical aerial photographs taken in
1977 AD (during the course of the dam works) (Fig. 4F), 1984 AD (just
at the end of the works) (Fig. 4G), and 2003 AD (18 years after the end
of the works) (Fig. 4H). A comparison between the 1956 AD and
1977 AD coastlines evidences erosion on the western side of the new
delta and deposition on its eastern side (Fig. 4F). The western side of
the new delta decreased in area by ≈105,000 m2 during this sevenyear period. In contrast, the eastern side accreted ≈186,000 m2.
Coastline retreat has been the dominant process since the Benínar
dam stopped sediment transfer to the river mouth. Thus, in 1984 AD,
87% of the new delta coastline was undergoing erosion (Fig. 4G). By
2002 AD, 93% of the new delta coastline had been eroded and the area
of the delta had diminished by ≈121,000 m2 with respect to 1984 AD
(Fig. 4H). During this 18-year period, the old western delta has also
eroded (Fig. 4H).
In order to quantify modern coastline changes, we have taken into
account only coastlines obtained from aerial photographs. Thus, we
have analyzed the coastlines at 1956 AD to 2002 AD with the aid of
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
Fig. 4. Coastline evolution for the different periods considered. See text for further explanations.
15
16
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
the DSAS software package (Thieler et al., 2009). We have examined
the changes through the definition of 30 transects perpendicular to
the coastline with 300 m-spacing from a baseline located onshore
(Fig. 8A). We have computed the rate of coastline advance/retreat
through linear regression of each transect with respect to the 4
coastlines used. As we have only 4 different coastlines, it is very
important to take into account the correlation coefficient of this linear
regression. In Fig. 8B, the rate of advance/retreat does not present a
clear pattern for transects 1 to 19, while for transects 20 to 30 the
coastline has undergone a clear retreat. Transects 20 to 30 show high
correlation coefficient, while transects 1 to 19 have low to very low
correlation coefficients.
To sum up, the analysis of the most recent (approx. last 50 years)
coastlines provides a systematic pattern of coast retreat only at the eastern
sectors of the area studied, which correspond to a little gulf located
westwards of the artificially carved channel of the Adra River (Fig. 8A).
8. Submarine morphology adjacent to the deltaic system
The interpretation of the submarine bathymetry in the vicinity of
the emerged delta plain allows us to distinguish three main morphosedimentary sectors from west-to-east (Figs. 9 and 10):
a) A complex system of sediment wedges is recognized west of Adra
city, occupying the inner shelf up to around 60 m water depth.
Within this system, two clearly distinguished morphological units
are evident. A compound of several sediment wedges occurs below
40 m water depth, outlining an overall lobate protuberance.
Landward, a well-defined sediment wedge extends laterally with
high continuity, defining a well-marked offlap break basically
parallel to the present-day coastline. This well-defined slope break
occurs at an approximate water depth of 20 m and quite a constant
distance from the present-day coastline, ranging in the study area
between 750 and 1050 m (Figs. 9 and 10).
The physiographic profile of this proximal wedge displays a welldefined sigmoid profile (Fig. 11). The upper topsets are generally
inclined less than 1°, and lower-scale morpho-sedimentary
features are superimposed over the topset. In particular, the distal
termination of an even more recent sediment wedge is recognized
in the western part of the study area over the topsets. Seawards
from the offlap break, a narrow (less than 200 m wide in the study
area) and abrupt foreset (in many places more than 10° and locally
steeper than 30°) is identified, but in contrast the bottomsets are
poorly developed.
b) An intermediate protuberance is identified just in front of the
ancient natural mouth of the river, extending more than 3 km
offshore to a maximum water depth of around 60 m (Figs. 9 and
10). A topset with a slope of less than 0.5° can be observed. Over
the topset, the distal terminations of very proximal wedges are
identified in the vicinity of Adra port. The offlap break occurs at a
maximum water depth of 18 m, shows an arched pattern in map
view, and is located more than 1 km from the coastline. The
offlap break bounds a very steep slope that can reach 5° in the
western part and more than 20° in its eastern part. However,
this slope is very narrow and has a width in map view of less
than 200 m in the western part and less than 20 m in its eastern
part. Seawards, the dip of the prodeltaic lobe decreases (Fig. 11),
but is always high and constitutes a foreset–bottomset. In the
foresets, inclines are highly variable, but values above 0.5–1° are
common. In contrast, in the bottomsets most of the slopes are
less than 0.5°.
The maximum width of this distal zone is around 2 km in a
southwest direction. The seaward distribution of the central
protuberance just east of Adra city seems to be controlled by the
presence of several sedimentary lineations, considered to represent
sediment ridges based on existing high-resolution seismic profiles.
The most notable lower-scale morphological pattern affecting the
intermediate protuberance is a wide area covered by undulations on
Fig. 5. Part of the map by Montojo y Salcedo (1876), which includes the study area. This map shows the existence of a single delta at that time and the presence of both the old natural
waterway near the village (Río Adra) and the first artificially dug channel (la corta).
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
17
Fig. 6. View towards the northwest of the artificial channel dug in 1873 AD.
the seafloor in the southwest of the prodeltaic lobe. The area with
undulations is more than 1.5 km in width normal to the prodeltaic
structure and more than 2.5 km laterally.
c) A set of wedges is identified seawards of the artificial present-day
river mouth in the east of the study area. At least two major bodies
or sedimentary wedges typified by well-defined offlap breaks are
observed (Figs. 8 and 10). High-resolution seismic profiles reveal
that these sediment wedges stack vertically, acquiring a backstepping stacking pattern.
The older major sediment wedge develops a rather elongate
distribution, and its offlap break basically parallels both the present
coastline and the offlap break of the younger wedge. Water depth of
the offlap break of the older wedge increases from east to west, but in
the middle part is about 20 m. Seaward from the topset–foreset break,
the physiographic profile shows a narrow foreset less than 250 m wide
and with inclines as high as 10° in the easternmost part close to the
offlap break and a wider bottomset with a maximum width of about
800 m and with inclines of less than 2°. The seaward termination of
this older wedge tends to follow the present coastline trend at
distances of 1250–1750 m.
The proximal major wedge develops an offlap break that parallels
the present-day coastline, with a main NE–SW orientation changing
to E–W just in front of the present-day river mouth. This offlap break
is 0.5 km from the coastline at a mean water depth of 10 m. Just off
the present-day river mouth, the distal termination of a more recent
third wedge is also apparent over the topsets of the proximal major
wedge. The proximal wedge shows a foreset segment extending no
more than 350 m from the landward offlap break and slopes that
locally may be steeper than 3°. The seaward termination of the
proximal wedge occurs less than 100 m from the offlap break of the
older wedge.
Fig. 7. View of the artificial levees built along the edges of the artificial channel dug in 1910 AD and reinforced after the 1973 AD flood.
18
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
Fig. 8. A: Location of baseline, transects and coastlines (at 1956 AD, 1977 AD, 1984 AD and 2002 AD) studied by means of the Digital Shoreline Analysis System software (Thieler et al.,
2009), B: Rates of coastline advance/retreat obtained by linear regression at the different transects, and variation of the correlation coefficients.
9. Estimation of volume changes during the 19th and 20th
centuries AD
The bathymetric data from the nautical chart of 1876 AD (Montojo y
Salcedo, 1876) and the bathymetric data from 2002 AD have been used to
derive two digital elevation models (DEM) of the sea bottom (DEM-1876
and DEM-2002). The two digital elevation models have been compared to
calculate volumetric changes over this 130-year period in the whole area
of Fig. 12. Despite RMS error in point location at 1876 AD is very high
(237.3 m), these data can, however, serve as a rough approximation on
the sediment volumes accreted/removed since this time. This comparison
shows the building of the eastern new delta with the accretion of
67,222,900 m3 of sediments, which corresponds to an average accretion
rate of ≈500,000 m3 of sediments per year. This rate is probably a
minimum one since the eastern delta is at present undergoing erosion due
to its submerged morphology (see next section).
The comparison of the two DEM (Fig. 12) also reveals the erosion of
the old delta around the natural river mouth. The total volume of
sediment eroded here is ≈9,029,600 m3, that is, 69,500 m3 of sediments
per year. Finally, our comparison shows significant sediment retention
just to the west of the harbor as a consequence of the dominant easterly
longshore drift.
The analysis performed can be used to estimate sediment yield rates in
the Adra River catchment. To do so, we have assumed an average density
for the sediments in the delta varying between 1.78 and 1.95 t/m3,
according to data extracted from offshore drills and inland gravimetric
modeling (Martínez-García and Soto, 2006; Duque et al., 2008). Taking
into account these two densities, the new delta would have accumulated
120,000,000 to 130,000,000 m3 tonnes of sediments during the 130-year
period considered in this estimation. Taking into account the area of the
catchment (744 km2), we can derive minimum sediment yield rates
between 1240 and 1350 t km− 2 year− 1 (1.2 to 1.3 kg m−2 year− 1).
These estimates are considerably greater than the 201.4 t km− 2 year− 1
provided by Liquete et al. (2005). This big difference can be related to the
very different methods of estimation, though the two figures could be
reconciled if a great part of the material in the new delta would have been
derived from the erosion of the ancient delta. Moreover, prior to the
construction of the harbor (beginning of 20th century AD) the easterly
longshore drift could also have supplied some material from other small
deltas located eastwards.
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
19
Fig. 9. Multibeam bathymetry of the continental shelf adjacent to the Adra delta.
10. Discussion and conclusions
The integration of the different data derived from our study,
namely coastline evolution and submarine sediment volumetric
changes, clearly reveals a strong anthropic imprint in the recentmost
evolution of the Adra River deltaic system. Deforestation of the
catchment, damming of the trunk river and deviation of the main
channel during the last 150 years have notably modified the
geometry of the deltaic system. This most recent human-driven
evolution contrasts with the previous climatically-driven evolution
of the deltaic system.
10.1. Development of the Adra delta under the dominant influence of
climatic factors
The Adra River deltaic system is thought to have started its
formation 6000 years ago, being conditioned most of the time by
climatic cycles, with accretion occurring during the wet periods. This
climatically-controlled stage initiated with the sediment infill of an
estuary and the subsequent formation of a very asymmetrical
triangular delta. Unfortunately, the three coastline reconstructions
performed for the time-span prior to the anthropic influence (4000 BC
to 1873 AD) do not match with well-defined wet or dry climatic
Fig. 10. Interpretation of main depositional elements (mostly sedimentary wedges) in the vicinity of the Adra River mouth.
20
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
Fig. 11. Bathymetric profiles of main sedimentary wedges see location in Fig. 10.
cycles. Nevertheless, it seems reasonable to assume that the natural
growth of the Adra delta would be basically controlled by these
climatic cycles, since other potential factors (tectonic activity, landslides, and significant fires) producing important sediment volumes in
the catchment are negligible at the time-scale considered.
Towards the end of this climatically-driven stage (19th century
AD), the amount of sediment supply increased due to the confluence
of both climatic and anthropic causes. This period is characterized by
increased rainfall (Rodrigo et al., 2000), which, in turn, would have
favored erosion in the catchment. The main anthropic factor
increasing sediment supply to the delta is the accelerated deforestation in the catchment during the last quarter of the18th century AD
and the first third of the 19th century AD, which would have triggered
erosional processes (Jabaloy-Sánchez, 1984). At present, the Adra
River system has a high value of estimated sediment load (Liquete
et al., 2005).
This stage of dominant climatically-controlled coastline advance is
also recorded in the submarine delta with the development of the
central protuberance. This wedge shows a basically lobate pattern with
a well-defined topset–foreset–bottomset geometry; it bears a close
resemblance to other shallow-water wedges in the proximity of the
study area, which have been interpreted as prodeltaic systems (Lobo
et al., 2006). The main axis of the central protuberance is perpendicular
to the old river mouth, indicating a moderate redistribution of sediment
and a great influence of river-borne sediment fluxes. The existence of
two dominant wave approaching directions oriented east and west-tosouthwest also favors moderate lateral redistribution processes. The
lobate distribution of the depocentre and the presence of an upper
Fig. 12. Areas of net deposition and erosion for the period 1876–2002 AD.
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
undulated surface also support the idea of significant sediment supply
with limited lateral redistribution. Similar undulations in other
prodeltas of the Granada coast have been related to hyperpycnal flows
and/or gravitational creep flows (Fernández-Salas et al., 2007).
10.2. Recent anthropic modifications of the deltaic system
The evolution of the coastline in the Adra delta over the last
150 years has been strongly controlled by anthropic factors, the most
important one probably being the artificial deviation of the river
channel in 1873 AD. The onshore influence of channel deviations has
been studied in other Mediterranean deltas (Longhitano and Colella,
2007), with the authors concluding that the main result is a decrease
in sediment input to the marine realm. In the area under study here,
two evolutionary stages can be distinguished according to the
different human influences since 1873 AD: i) the first one corresponds
to the period before the damming in 1984 AD of the trunk river in the
central sector of the catchment; and ii) the second one corresponds to
the very recent retreat of the coastline after construction of the
Benínar dam.
The first stage is characterized by the development of a delta in the
new, artificial river mouth. At the same time, the old delta in the
natural river mouth has been undergoing continuous erosion. A rough
estimate of sediment weights implied in the construction of this new
delta surpasses sediment yield values obtained by Liquete et al.
(2005), suggesting that part of the material comes from the erosion of
the old delta.
The second stage is characterized by a radical decrease in sediment
supply to the coastline, thus favoring widespread coastline erosion.
Similar coastline erosional processes triggered by human interventions
are common in other coastal deltaic areas (e.g., Fan et al., 2006, El Banna
and Frihy, 2009; Sabatier et al., 2009; Simeoni and Corbau, 2009).
Studies on other adjacent fluvial systems associated to small rivers
flowing from high relief areas to the Mediterranean coast in Southern
Spain indicate a similar variation of fluvial sediment discharges during
the historical period. For instance, in the Vélez and Guadalfeo River
systems, Senciales-González and Málvarez (2003) have shown a
similar behavior with a high sediment supply during the first half of
the 20th century AD, which shifts towards erosion or steady state after
river diversion and dam building.
In the submarine realm, this human-driven evolution probably
promoted the development of some of the eastern sediment wedges
during the period prior to the building of the Benínar dam. These
sediment wedges contrast with the previously formed prodeltaic lobe
in the central sector of the submarine realm. The across-shelf extent of
the eastern sediment wedges is considerably smaller than the extent
of the prodeltaic lobe. This fact might be induced, at least partially, by
the poor representation of the bottomsets. Another distinctive
geomorphic feature of these wedges is their more elongate distribution when compared with the central protuberance. A final important
feature of the eastern wedges is their composite character. At first
sight, it seems largely speculative to relate the formation of the
different sediment wedges to the different coastline evolutionary
stages previously described. However, we can obtain clues about the
genetic link between coastal and shallow-water processes by
observing the areas of net accumulation and erosion for the period
from 1873 AD to 2002 AD (Fig. 10). Thus, the largest proximal wedge
appears to have been generated during the first anthropic stage (i.e.,
between 1873 AD and 1984 AD) since the area corresponding to this
wedge shows sediment accumulation. Obviously, this sediment
accumulation can only be previous to the construction of the Benínar
dam. The comparison of the1876 AD and 2002 AD bathymetries also
reveals that the proximal western wedge was constructed during this
period, probably in relation to the effect of the Adra harbor on the
easterly longshore drift. In contrast, most of the central protuberance
21
has been undergoing erosion during the entire human-driven period
of coastline evolution.
The submarine realm as a whole during the human-driven period
(1873 AD to present-day) seems to have undergone a decrease in
sediment supply, with erosional and redistribution processes having
gained in importance. Thus, the elongate nature and steep profile of
the sediment wedges on both sides of the central protuberance make
them more similar to infralittoral wedges in nearby shallow-water
areas (Fernández-Salas, 2008; Fernández-Salas et al., 2009) than to
prodeltaic bodies. The initial interpretation of infralittoral prograding
wedges considered them to be mainly linked to seaward sediment
transport led by downwelling storm currents (Hernández-Molina
et al., 2000). However, later work revealed that infralittoral prograding wedges in coastal segments with significant longshore currents
may accrete parallel to oblique to the coastline. In other Mediterranean prodeltaic areas, such as the Adriatic Sea, elongate sediment
wedges also develop laterally from fully developed prodeltaic wedges,
this pattern mainly resulting from coast-parallel advection (Cattaneo
et al., 2003; Correggiari et al., 2005). Accordingly, we propose that a
component of lateral growth may also have been active in the study
area due to lateral redistribution processes, as suggested by the
identification of erosional areas in the older central area. Therefore,
we estimate that the genesis of these anthropogenically-induced
sediment wedges is complex, forming mainly from coastal sediments
remobilized by lateral advection, although subordinate sediment
input from the reduced fluvial source may have remained.
Acknowledgements
The swath bathymetric data have been obtained with the support
of the project ESPACE (Estudio de la Plataforma Continental
Española), performed by the Instituto Español de Oceanografía and
the Secretaría General de Pesca Marítima. This work has been carried
out in the framework of several research projects, namely TOPOIBERIA CONSOLIDER-INGENIO CSD2006-00041, CGL2008-03249/BTE
and CTM2005-04960/MAR, funded by the Spanish Ministerio de
Ciencia e Innovación, as well as the project entitled“Modelado,
Simulación Numérica y Análisis del Transporte de Sedimentos en los
Abanicos Submarinos de los Ríos de Andalucía Oriental” (MOSAICO),
funded by the Junta de Andalucía. We have also received financial
support from RNM-327, RNM-215 and RNM-148 research groups of
the Junta de Andalucía, as well as grant MMA-083/2007 of the
Ministerio de Medio Ambiente y Medio Rural y Marino. We would like
to thank the Instituto de Cartografía de Andalucía from the Consejería
de Obras Públicas of Andalucía and the Biblioteca de Andalucía for
providing us with copies of the map of Montojo y Salcedo (1876).
Thanks are also given to Christine Laurin for revising the English text.
Wave data have been gently provided by Puertos del Estado from the
Spanish Ministerio de Fomento. Comments and suggestions made by
Pr. U. Simeoni, Dr. C. Corbau and an anonymous reviewer are greatly
appreciated.
References
Aubet-Semmler, M.E., 2002. Phoenician Trade in the West: Balance and Perspectives.
In: Gitin, S. (Ed.), The Phoenicians in Spain. An Archaeological Review of the
Eighth–Sixth Centuries B.C.E. — A Collection of Articles Translated from Spanish
Translated by Marilyn Bierling. Eisenbrauns Inc., pp. 97–112.
Braga, J.C., Martín, J.M., Quesada, C., 2003. Patterns and average rates of late Neogene–
Recent uplift of the Betic Cordillera, SE Spain. Geomorphology 50, 3–26.
Cattaneo, A., Correggiari, A., Langone, L., Trincardi, F., 2003. The late-Holocene Gargano
subaqueous delta, Adriatic shelf: sediment pathways and supply fluctuations. Marine
Geology 193, 61–91.
Correggiari, A., Cattaneo, A., Trincardi, F., 2005. The modern Po Delta system: lobe
switching and asymmetric prodelta growth. Marine Geology 222–223, 49–74.
Cuéllar-Villar, D., 2006. Historia de una obra pública: la desviación del Río Adra (1862–1873).
Farua, Revista del Centro Virgitano de Estudios Históricos Centro Virgitano de Estudios
Históricos del Ayuntamiento de Berja (Almería) Volumen extra I, pp. 101–112.
22
A. Jabaloy-Sánchez et al. / Geomorphology 119 (2010) 9–22
Dornbusch, U., Robinson, D.A., Moses, C.A., Moses, C.A., Williams, R.B.G., 2008. Temporal
and spatial variations of chalk cliff retreat in East Sussex, 1873 to 2001. Marine
Geology 249, 271–282.
Duque, C., Calvache, M.L., Pedrera, A., Martín-Rosales, W., López-Chicano, M., 2008.
Combined time domain electromagnetic soundings and gravimetry to determine
marine intrusion in a detrital coastal aquifer (Southern Spain). Journal of
Hydrology 349, 536–547. doi:10.1016/j.jhydrol.2007.11.031.
El Banna, M.M., Frihy, O.E., 2009. Human-induced changes in the geomorphology of the
northeastern coast of the Nile delta, Egypt. Geomorphology 107, 72–78.
Fan, H., Huang, H., Zeng, T., 2006. Impacts of anthropogenic activity on the Recent
Evolution of the Huanghe (Yellow) River Delta. Journal of Coastal Research 22,
919–929.
Fernández-Salas, L.M., 2008. Los depósitos del Holoceno Superior en la plataforma
continental del sur de la Península Ibérica: Caracterización morfológica y estratigráfica. Ph. Dr. Thesis, University of Cadiz, Spain. 278 pp.
Fernández-Salas, L.M., Lobo, F.J., Sanz, J.L., Diaz-del-Rio, V., Garcia, M.C., Moreno, I.,
2007. Morphometric analysis and genetic implications of pro-deltaic sea-floor
undulations in the northern Alboran Sea margin, western Mediterranean Basin.
Marine Geology 243, 31–56.
Fernández-Salas, L.M., Dabrio, C.J., Goy, J.L., Díaz del Río, V., Zazo, C., Lobo, F.J., Sanz, J.L.,
Lario, J., 2009. Land–sea correlation between Late Holocene coastal and infralittoral
deposits in the SE Iberian Peninsula (Western Mediterranean). Geomorphology
104, 4–11.
Gómez-Cruz, M., 1991. Atlas histórico forestal de Andalucía del S. XVIII. Servicio de
Publicaciones de la Universidad de Granada, Granada, Spain. 71 pp.
González Trueba, J.J., Martín Moreno, R., Martínez de Pisón, E., Serrano, E., 2008. ‘Little
Ice Age’ glaciation and current glaciers in the Iberian Peninsula. Holocene 18,
551–568.
Guerrero-Montero, F.M., 2005. Terremotos y desastres naturales en la Provincia de
Almería en el Siglo XIX. Farua, Revista del Centro Virgitano de Estudios Históricos,
Centro Virgitano de Estudios Históricos del Ayuntamiento de Berja (Almería), 8,
pp. 13–23.
Hernández-Molina, F.J., Fernández-Salas, L.M., Lobo, F., Somoza, L., Díaz-del-Río, V.,
Alveirinho Dias, J.M., 2000. The infralittoral prograding wedge: a new large-scale
progradational sedimentary body in shallow marine environments. Geo-Marine
Letters 20, 109–117.
Hoffmann, G., 1987. Holozänstratigraphie und Kustenlinienverlagerun an der Andaluscishen mittelmeerküste. Ph. Dr. Thesis, University of Bremen., 161 pp.
Jabaloy-Sánchez, A., 1984. Evolución de la desembocadura del Río Adra (Almería). I
Congreso Geológico de España, Abstracts 1, 523–534.
Junta de Andalucía, 2007. Mapa de Andalucía 1: 50.000. 1940–1944. Cartografía del
estado Mayor del Ejercito Alemán (Spanien 1: 50.000 Deustche Heeresskarte). CDRom.
Kaya, S., Sertel, E., Seker, D.Z., Tanik, A., 2008. Multi-temporal analysis and mapping of
coastal erosion caused by open-mining areas. Environmental Forensics 9, 271–276.
doi:10.1080/15275920802123963.
Liquete, C., Arnau, P., Canals, M., Colas, S., 2005. Mediterranean river systems of
Andalusia, southern Spain, and associated deltas: a source to sink approach. Marine
Geology 222–223, 471–495.
Lobo, F.J., Fernández-Salas, L.M., Moreno, I., Sanz, J.L., Maldonado, A., 2006. The sea-floor
morphology of a Mediterranean shelf fed by small rivers, northern Alboran Sea
margin. Continental Shelf Research 26, 2607–2628.
Longhitano, S., Colella, A., 2007. Geomorphology, sedimentology and recent evolution
of the anthropogenically modified Simeto River delta system (eastern Sicily, Italy).
Sedimentary Geology 194, 195–221.
Martínez-García, P., Soto, J.I., 2006. Valores de subsidencia reciente (Plioceno–
Cuaternario) en el Mar de Alborán mediante análisis de “backstripping”. Geogaceta
40, 63–66.
Martínez-Martínez, J.M., Booth-Rea, G., Azañón, J.M., Torcal, F., 2006. Active transfer
fault zone linking a segmented extensional system (Betics, southern Spain): Insight
into heterogeneous extensión driven by edge delamination. Tectonophysics 422,
159–173. doi:10.1016/j.tecto.2006.06.001.
Mateo, Z.R.P., Siringan, F.P., 2007. Tectonic control of high-frequency Holocene delta
switching and fluvial migration in Lingayen Gulf bayhead, northwestern
Philippines. Journal of Coastal Research 23, 182–194.
Maurya, D.M., Thakkar, M.G., Patidar, A.K., Bhandari, S., Goyal, B., Chamyal, L.S., 2008.
Late Quaternary geomorphic evolution of the Coastal Zone of Kachchh, Western
India. Journal of Coastal Research 24, 746–758.
Montojo y Salcedo, J., 1876. Cartas náuticas III. Motril (Granada). Dirección de Hidrografía
(Madrid) España.
Paracuellos-Rodríguez, M., 2006. Las Albuferas de Adra (Almería, Sudeste ibérico) y su
relación histórica con el hombre. Farua, Revista del Centro Virgitano de Estudios
Históricos Centro Virgitano de Estudios Históricos del Ayuntamiento de Berja
(Almería),Volumen extra I, pp. 335–358.
Rodrigo, F.S., Esteban-Parra, M.J., Pozo-Vázquez, D., Castro-Díez, Y., 1999. A 500-year
precipitation record in Southern Spain. International Journal of Climatology 19,
1233–1253.
Rodrigo, F.S., Esteban-Parra, M.J., Pozo-Vázquez, D., Castro-Díez, Y., 2000. Rainfall
variability in Southern Spain on decadal to centennial time scales. International
Journal of Climatology 20, 721–732.
Rumsey, D., Williams, M., 2002. Historical maps in GIS. In: Knowles, A.K. (Ed.), Past
Time, Past Place: GIS for History. ESRI Press, Redlands, CA, pp. 1–18.
Saalfeld, A., 1985. A fast rubber-sheeting transformation using simplicial coordinates.
American Cartographer 12, 169–173.
Sabatier, F., Samat, O., Ullmann, A., Suanez, S., 2009. Connecting large-scale coastal
behaviour with coastal management of the Rhône delta. Geomorphology 107,
79–89.
Senciales-González, J.M., Malvárez, G., 2003. La desembocadura del Río Vélez (Provincia
de Málaga, España). Evolución reciente de un delta de comportamiento
Mediterráneo. Revista C. & G. 17, 47–61.
Simeoni, U., Corbau, C., 2009. A review of the Delta Po evolution (Italy) related to
climatic changes and human impacts. Geomorphology 107, 64–71.
Thieler, E.R., Himmelstoss, E.A., Zichichi, J.L., Ergul, 2009. Digital Shoreline Analysis
System (DSAS) version 4.0—an ArcGIS extension for calculating shoreline change.
U.S. Geological Survey Open-File Report 2008-1278.
Tobler, W.R., 1994. Bidimensional regression. Geographical Analysis 26, 187–212.
Xeidakis, G.S., Delimani, P., Skias, S., 2007. Erosion problems in Alexandroupolis
coastline, North-Eastern Greece. Environmental Geology 53, 835–848.