Ecology. 62(1), 1981, pp. 13-19
© 1981 by Ihe Ecological Society of America
DECOMPOSITION RATES AND NUTRIENT CONTENTS OF
ARTHROPOD REMAINS IN FOREST LITTER1
T. R. SEASTEDT2 AND C. M. TATE
Department of Entomology and Institute of Ecology, University of Georgia, Athens, Georgia 30602 USA
Abstract. Decomposition rates and amounts of calcium, magnesium, potassium, and phosphorus
were measured for dead millipedes and crickets buried in forest litter in North Carolina and Georgia.
An average of 30% of the original mass of millipedes and 14% of the original mass of crickets was
recovered after 1 yr in the litter. Elemental losses generally followed the pattern: K.S* P > Mg > Ca;
however, elemental amounts ocassionally stabilized and in one experiment calcium increased in
amount over time.
Decomposition of arthropod carcasses was described by a two-component, negative exponential
decay model. Decay coefficients were used with literature estimates of arthropod standing crops to
estimate standing crops of mass and elements of arthropod remains in forest litter and soil. Estimates
of standing crops of mass, calcium, and magnesium of arthropod remains were greater than those of
living forcsl floor arthropods.
Key words: arthropods; crickets; decomposition; forest floor; Georgia: millipedes; North Carolina; nutrients.
INTRODUCTION
Studies of the energy and nutrient dynamics of arthropod populations have been concerned primarily
with standing crops and productivity (Engelmann
1961, Wiegert and Evans 1967, Golley 1968, Reichle
et al. 1969, Van Hook 1971, Carter and Cragg 1976).
However, data are available that suggest that the
amounts of mass and elements contained in dead arthropod remains found in forest litter may equal standing crop estimates of living biomass. Cornaby (1973)
measured the amount and elemental composition of
arthropod remains found in the litter of a southern
Appalachian pine forest. He reported 948 mg/m- of
arthropod exoskeletons vs. an annual average of
= 1150 mg/m2 of living arthropod biomass. The estimate was obtained by hand-sorting litter, and given
the small size of many or most exoskeleton fragments,
the amount of arthropod remains was likely underestimated. Cornaby also reported a much greater amount
of calcium and approximately half the amounts of potassium and magnesium in invertebrate remains than
were found in living invertebrates.
No quantitative studies have been conducted on
the decompositioo or elemental release from arthropod carcasses. However, Gray'and Bell (1963) studied
microflora colonization and decomposition of chitin
associated with protein, and Okafor (1966o) conducted
similar studies on pure chitin. Both studies indicated
fairly rapid decomposition of these materials. Okafor
(19666) also studied the microbial colonization and
decomposition of insect wings. He did not measure
mass loss, but found intact pieces of wings after 300
1
Manuscript received 2 January 1979; accepted 16 April
1980.
2
Present address: University of Montana Biological Station, Bigfork, Montana 59911 USA.
d in soil. Veldkamp (1955) also reported carabid beetle
elytra to decompose very slowly; however, results
were not quantified.
The present study reports on the decomposition and
calcium, potassium, magnesium, and phosphorus concentrations of dead millipedes and crickets placed in
forest litter. A two-component, exponential decay
model was fitted to the data, and the model was then
used in conjunction with published estimates of standing crops and turnover rates to estimate standing crops
of mass and elements of arthropod remains in forest
litter.
METHODS
Adult specimens of the millipede, Cherokia georgiana, were collected from a deciduous hardwood forest at the Coweeta Hydrologic Laboratory in the
southern Appalachians of North Carolina. These were
killed by freezing, dried at 60°C, and weighed. Domestic crickets, Achcta domcsticus. were obtained
from a supplier of fish bait and subjected to a similar
treatment. Forty of each species were individually
placed in small ( 5 x 5 cm) nylon mesh bags («2-mm
mesh), and these bags were buried in the litter of a
deciduous hardwood forest (watershed 2) at Coweeta
on 10 June 1978. Usually four bags of each species
were recovered from the field at 1- or 2-wk intervals
during the 1st 2 mo of the experiment, and at more
widely separated intervals thereafter. Remains were
cleaned of debris with forceps, redried, weighed, and
stored for nutrient analysis.
A second study site was established in a hardwood
forest located in the piedmont region of north Georgia
at the University of Georgia Botanical Gardens, 160
km south of Coweeta. Only crickets were used at this
site. About 40 bags were placed in the field during late
July 1978, and another 100 bags were buried in litter
T. R. SEASTEDT AND £. M. i ATE
Ecology, Vol. 62, No. 1
OMILLIPEDES
• CRICKETS
lOOi:
80
6040-
-40
o
o
20-
20
-10
i '°"
\ 5H
5
o:
tn
s
COWEETA
OL
Q
lOOj
LJ
80
O
a:
60UJ
a.
40
-40
20-
20
—1_.
--x
?
——8--—-j.
•
la-
-10
BOTANICAL GARDENS
160
240
365
AGE OF CARCASS (DAYS)
FIG. 1. Percent of initial dry masses of millipede and cricket remains recovered from forest litter. The experiment at
Coweeta was initiated on 10 June 1978, that at the Botanical Gardens on 1 October 1978. Lines represent the regression In
(percent of initial mass) against age of remains, for carcasses, older than 14 d. Zero values (points below the y-axis) and
points near 0% (one point for millipedes, two points for crickets) were not used in the regression.
14
80
in early October 1978. Besides measuring mass and
nutrient losses, these bags were used to measure arthropod abundance on cricket remains. Those findings
are reported elsewhere (Seastedt et al., in press). Unlike the Coweeta experiments, fresh rather than dried
crickets were used, and bags were harvested at 2- or
4-d intervals during the 1st mo of the study. Initial dry
masses of the crickets were estimated by regression
analysis.
Nutrient analysis employed a wet digestion procedure to maximize potassium recovery (Carter and
Cragg 1976). The procedure used here was modified
from Blood and Grant (1974). Dried cricket and millipede remains were weighed in acid-washed crucibles
and 5 ml of 3 HNO3:1 H,SO4; 1 HPC1O4 acid mixture
was added to each crucible. These were then incubated in a water bath at 75°C for 2 h. Cricket samples
were diluted with water to 25 ml in volumetric flasks;
millipede samples were diluted with 20% acid mixture
to 200 ml. The extra dilution factor for millipedes was
necessary to dissolve the large amounts of calcium
found in their exoskeletons. National Bureau of Standards' bovine liver, prepared standards, and reagent
blanks were run with each block of samples to monitor
the accuracy and^recision of the procedure. Samples
and standards were analyzed for Ca, K, Mg, and P
with an inductively coupled plasma emission spectrometer. Because of the dilution factor of 200 used
for millipedes, atomic absorption spectroscopy was
used to measure potassium in these organisms.
RESULTS
Mass loss
Mass loss of millipede and cricket carcasses exhibited a pattern previously reported for vertebrate carcasses (Payne 1965); rapid mass loss was observed
during the 1st 2 wk, followed by an extended period
February 1981
DECOMi'U:-
of very slow decay (Fig. 1). Unlike vertebrates, how
ever, complete or nearly complete consumption of the
carcasses was occasionally observed. Rapid mass loss
was attributed to consumption by maggots, ants, beetles, and other macroinvertebrates that were found on
the carcasses during the 1st 2 wk of the study, while
the slow decomposition rate observed in older carcasses was attributed to microfloral respiration and
microarthropod consumption (Seastedt et al., in
press).
The observed decay pattern resembled the twocomponent curve of radioisotope elimination described for arthropods (e.g., Crossley and Reichle
1969, Gist and Crossley 1975, Webster and Crossley
1978), and this type of model was applied to the data.
Mass loss was calculated from the formula
i he decomposition rate of crickets during the 1st 14
d of the summer Botanical Garden experiment appeared greater than the rates observed at the same site
during October or during June at Coweeta. Environmental conditions, particularly warmer temperatures,
likely facilitated more rapid decomposition directly,
via stimulation of microbial activity (Okafor 1966o),
and indirectly, by creating an environment more conducive to attracting and maintaining carrion-feeding
invertebrates (Seastedt et al., in press).
The y-intercept of the second component (X2) provided an estimate of the initial amount of recalcitrant
remains. For millipedes, the intercept was 59.6%;
crickets varied from 13.6% at Coweeta to 26.2% at the
Botanical Gardens. The intercept values were positively correlated with the ash content of the arthropods (=35% for millipedes, 7% for crickets), and the
dXIdt = ktX1 + k.jXi,
amount of macroinvertebrate consumption that ocwhere £, and A 2 are decay coefficients and Xl and X., curred during the 1st 2 wk of decomposition. These
are the fractions of easily decomposable and recalci- factors were not mutually exclusive; ash content was
trant portions, respectively, of a species of arthropod. proportional to the degree of sclerotization of the exoThe percent of carrion remaining at time t is therefore skeleton, while carrion consumption appeared to be
directed primarily at non-exoskeleton tissues. The X.t
X2e*>'.
X, =
(1)
component may simply represent "what's left" folSolving for the decay constants and initial values for lowing removal of soft tissues. The variation in initial
X{ and X., is essentially the same procedure as that values observed in cricket remains indicated that porused for separating mixtures of radioisotopes (Webster tions of exoskeleton materials may or may not be initially consumed based on environmental factors or
and Crossley 1978).
Exponential decay curves approach but never equal. other variables. Overall, however, the X.2 component
zero. However, the half-life of the.components may may be similar to material left by predators that do
not completely consume arthropod prey.
be calculated by the formula
Exoskeleton remains of crickets in litter at Coweeta
'i = dn 2)/kt
decomposed more rapidly than remains of millipedes
(e.g., Gist and Crossley 1975). About 97% of the com- at Coweeta or crickets at the Botanical Gardens. Unponent has decayed after five half-lives, hence a value fortunately, the length of data collection for Coweeta
of five times the half-life estimate was used to approx- was much shorter than that of the other two experiimate the decay time of an arthropod carcass.
ments and reflected decay during a summer environThe model (Eq. 1) applied only to partial consump- ment only. Crickets placed in litter in October did not
tion of internal structures by macroinvertebrate car- show enhanced decomposition the following summer
rion feeders, followed by microbial and microarthro- (Fig. 1), hence the age of the carcass as well as envipod consumption of exoskeleton remains. A second ronmental conditions appeared to be factors influencpathway, complete or nearly complete consumption ing decay rates. These data suggest that a multicomof carcasses by macroinvertebrates or vertebrates, ac- partmental model, such as that proposed for leaf litter
counted for seven of 148 observations (4.7%). Zero (Minderman 1968), may more accurately describe the
and near-zero percent values (<5% of initial masses decomposition of arthropod carrion. However, the
of millipedes and <2.5% of initial masses of crickets) data were sufficient to indicate that the time involved
were not used in the model. Thus, the calculated de- for the disappearance of arthropod remains (i.e., five
composition coefficients were applicable to =95% of half-lives) is lengthy; millipede remains require =5 yr,
while cricket exoskeleton materials require from 1 to
the carcasses observed here.
The parameters of the decomposition model are re- 5 years to decompose completely.
ported in Table 1. The detay constant reported for the
Nutrient loss
summer experiment conducted at the Botanical Gardens is the sum of both &, and k.2 and is therefore an _
Elemental concentrations of the two arthropods and
underestimate of kt (Reichle 1969). Insufficient data concentrations found in arthropod remains are sumexisted to calculate values for k.2 and X., in that ex- marized in Table 2. Initial elemental concentrations of
periment. However, as the fractional amounts of X.2 the millipedes and crickets were within the range of
calculated for crickets in the other experiments are values reported for millipedes and orthopterans by
Reichle et al. (1969). Changes in elemental concentrasmall (Table 1), the error is believed small.
T. R. SEASTEDT AND C. M > A i E
Ecology, Vol. 62, No. I
TABLE 1. • Decomposition rates and half-lives
of arthropod carrion. The parameters given below are derived from a decomposition model of the form X, = Xtekl1 + X2el12' and from calculation of half-lives using the formula /j = (In 2)/K,.
Site
Coweeta*
Arthropod
Easily decomposed fraction (Xt)
Fraction of
initial
amount
Half-life
*,
(d-1)
(d)
(%)
(«)
Recalcitrant fraction (XJ •
Fraction of
initial
amount
Half-life
*,
(d-)
(n)
(d)
(%)
40.4
-.052
13.5
Millipede
(3)
Cricket
86.4
-.076
9.2
(5)
Botanical Gardens
100.0
-.249
2.8
(29)
Crickett
Crickett
-.117
(16)
74.8
5.9
* Experiment initiated 10 June 1978. Data shown in Fig. 1.
t Experiment'initiated 31 July 1978. No second component (X2) calculated.
t Experiment initiated 1 October 1978. These data are shown in Fig. 1.
dons followed similar trends in the three experiments;
calcium tended to increase while other elements eventually decreased in concentration'. The element most,
rapidly lost was potassium, and the behaviors of this
and the other cations were similar to those observed
for cations in leaf litter decomposition (e.g., Gosz et
-al. 1973). Phosphorus was immobilized for a few
months in .millipedes, but was not immobilized in
.cricket remains. Although this element was not lost as
rapidly as potassium, overall losses of phosphorus
were equal to or greater than potassium.
Nutrient data were converted to percent of initial
amounts, and decay coefficients and half-lives of the
recalcitrant fractions were calculated. These were
compared with similar values calculated for mixed leaf
litter placed in litter bags at Coweeta in 1970 (Cromack
59.6
13.6
-.002
-.010
359
65
(35)
(26)
25.2
-.0015
449
(57)
1973; Table 3). Calcium losses followed mass losses
for millipedes, crickets, and leaf litter at Coweeta, but
the amount of calcium in cricket remains at the Botanical Gardens showed significant (P < .05) increases over time. Fungal hyphae may have imported
this nutrient into the relatively calcium-poor exoskeletons, or microbes may have immobilized calcium obtained from rainfall, throughfall, or litter leachates
(Graustein et al. 1977, Cromack et al. 1979).
Magnesium losses were similar to or greater than
mass losses for millipedes, crickets, and leaf litter. The
behaviors of potassium and phosphorus in animal remains, however, were different from those observed
in leaf litter. In all cases animal remains either lost
these elements more rapidly than leaf litter, or showed
no significant losses in amounts after the 1st 14 d.
TABLE 2. Concentrations of elements in arthropod remains..
Age of
Sample
carcass
size
Arthropod
(d)
(n)
0
6
Millipede (Coweeta)
14
3
4
28
4
49
84
2
180
2
3
365
Cricket (Coweeta)
0*
23
14
5
28
3
49
3
84
6
Cricket (Botanical
12
4
4
Gardens, October)
28 '
44
4
74
8
6
122
240
9
* Pooled for all cricket experiments,
t No data.
<
Elemental concentrations as percent dry mass
(SE)
Ca
K.
Mg
P
0.47 (.02)
0.44 (.02)
11.32C93)
.07 (.08)
20.49 (2.61)
0.75 (.06)
.25 (.08)
t
0.82 (.10)
21.22 (.88)
.59 (.19)
t
0.20 (.01)
0.64 (.01)
20.35(1.16)
.56 (.10)
0.67 (.12)
23. 12 (.72)
0.08 (.02)
.40 (.19)
0.1 5 (.63)
0.53 (.07)
.23 (.04)
20.33 (1.75)
39.28 (.34)
0.23 (.01)
0.12 (.01)
0.14 (.02)
0.14(.01)
0.90 (.02)
0.13 (.01)
1.24 (.03)
0.22 (.05)
0.81 (.21)
0.24 (.08)
0.60 (.16)
0.41 (.03)
0.13 (.03)
0.51 (.13)
0.21 (.10)
0.10 (.04)
0.20 (.05)
0.36 (.17)
t
0.12 (.01)
0.39 (.05)
0.06 (.01)
0.35 (.03)
0.08 (.00)
0.07 (.02)
0.50 (.03)
0.40 (.03)
0.08 (.01)
0.07, (.01)
0.33 (.07)
0.35 (.03)
0.08 (.01)
0.29 (.02)
0.30 (.02)
0.07 (.00)
0.11 (.02)
0.1 7 (.04)
0.14(.OI)
0.26 (.03)
0.07 (.01)
0.1 2 (.02)
0.1 1 (.02)
0.16 (.01)
0.09 (.01)
0.21 (.02)
0.16 (.04)
0.26 (.03)
February 1981
LH-XUMTI .'
TABLE 3. Decay coefficients (fractional loss per day) and half-lives (days) of mass and elemental amounts in arthropod
remains buried in litter for > 14 d compared with decay rates of mixed leaf litter. NS = not significantly different from zero,
P > .05.
Mass
Decay coefficient (A2) and half-life (f t )
Ca
K
Mg
P
k,
k,
Material
k.
ti ,
k2
<i
'i
^
tt
, 'i
Millipedes
-.002
359 -.002
347 -.000 fas)
—
-.003
(Coweeta)
231 -.004
173
Crickets (Coweeta)
-.01
65 -.02
32 -.006 fas)
—
-.021
33 -.01 2 fas)
—
Crickets (Botanical)
449 + .002
Gardens)
-.0015
— -.005
139
-.003
231 -.007
99
Mixed leaf
litter (Coweeta)
-.002
351
-.0015
468 -.004
172
-.003
255 -.0015
468
* Mixed leaf litter data are from Cromack (1973) and are based on single negative exponential model. Dominant leaf species
included Quercus prinus, Q. alba, Acer rubrum, and Cornus florida.
These latter observations indicate that, the majority of
K and P in animal remains was quickly lost (Table 2),
and amounts subsequently stabilized in older carcasses. Carrion bags, like litter bags, are open systems and
subject to inputs as well as outputs. After an initial
period of elemental losses, leaf litter and woody litter
may stabilize or actually increase in elemental content
(Gosz et al. 1973, Seastedt and Crossley 1980).
The procedure of Olson (1963) was used to estimate
standing crops of mass and elements in arthropod remains found on the forest floor. Estimates of standing
..crops of arthropods at Coweeta from Gist (1972) for
a hardwood forest (watershed [WS] 18) and Cornaby
(1973) for a pine forest (watershed [WS] 17) .were used
in conjunction with measured decay rates of biomass
and elements, and amounts were calculated by the for• mula
•^i steady stale = ltlpM,/k,.
Masses and elemental amounts were calculated separately for the X, and X., components, and these are
reported in Table 4. A turnover rate of three times the
annual standing crop was used to estimate biomass
production (Wiegert and Evans 1967). Annual spider
predation has been estimated to account for 2.3 times
the standing crop of the arthropod community in a
Tennessee forest (Moulder et al. 1970); thus, the production estimate appears reasonable. Assuming that
predation accounts for most arthropod deaths, the values of standing crops of X, materials in Table 4 are
overestimates (i.e., predators immediately consume
most non-exoskeleton materials). Values for recalcitrant materials (A',) probably represent more realistic
estimates of standing crops of arthropod remains in
litter and soil.
Decay constants calculated for millipedes were also
used to estimate oribatid mite decomposition; cricket
data obtained from the Botanical Garden experiment
TABLE 4. Standing crops of elements in leaf litter and living and dead forest floor arthropods for two Coweeta forests.
Standing crop (kg/ha)
Ca
K
Mg
P
22.1
.097
128.1
.026
t
*
.700
.028
1.154
1.182
.026
.009
.023
.032
.029
.015
.035
.048
*
.007
.052
.059
112.0
4.975
.201
14.670
14.871
24.7
.237
.015
.129
.194
t
i
.009
.382
.391
t
*
.023
.555
.578
Source
Mass
Leaf litter*
Living arthropods*
Dead arthropods
Cornaby (1973)
This study X,
This study X.,
Total, this study
2428.6
11.50
104.6
.170
9.48
.82
12.57
13.39
Leaf litterf
Living arthropodst
This study X,
This study X2
Total, this study
* Data from Cornaby (1973).
t Data from Gist (1972).
% No data.
2139.0
35.60
2.25
73.86
76. J l
Site
Pine forest
(Watershed 17)
Hardwood forest
(Watershed 18)
,.
*
were used for other arthropods. Since the model applied to =95% of the carcasses observed in this study,
a correction factor of 0.95 was applied to standing crop
estimates. Losses for elements not showing significant
changes in amounts were assumed to equal mass losses. We assumed that elements were being incorporated into microbial biomass rather than remaining immobilized within arthropod remains. The results of
these calculations were only crude approximations but
compared favorably with standing crop estimates reported by Cornaby (1973). Cornaby's pine forest was
rather depauperate in forest floor arthropods, partic. ularly millipedes, when compared with other watersheds at Coweeta (Gist 1972, T. Seastedt and D.
Crossley, personal observation). Estimates of standing crops of elements in arthropod remains found on
the hardwood watershed were therefore much larger
than those from the pine watershed. Regardless of the
standing crop estimate, however, masses and calcium
and magnesium in arthropod remains exceeded living
standing crops on the respective watersheds. Potassium in arthropod remains averaged about half that
found in living arthropods. Previous studies did not
estimate standing crops of phosphorus. Assuming that
phosphorus averaged ~\% dry mass of living biomass
(McBrayer 1977), then phosphorus content of arthropod remains was —50% of that found in living biomass
on WS 17 and 160% of that found on WS 18.
Values of living and dead arthropod mass and elemental amounts were also compared with average
standing crops of leaf litter (the L horizon) reported
by Gist (1972) and Cornaby (1973). Standing crops of
mass and elements in arthropod remains usually
amounted to <1% of respective leaf litter values: however, the standing crop of calcium in arthropod remains in the hardwood forest was >10% of that found
in leaf litter.
DISCUSSION
Nonpredatory mortality of arthropods occasionally
accounts for a significant fraction of population losses
(e.g., White et al. 1979). More importantly, spiders,
centipedes, or other invertebrate and vertebrate predators often reduce arthropod prey to exoskeleton remains, either as unconsumed portions of wings, legs,
and olhcr exoskeleton fragments, or as chitinous fragments in feces. Exoskeleton remains are also produced during arthropod molts. Certain species of millipedes and other arthropods consume their exuviae;
however, most arthropods do not. We postulate that
these remains decompose at a rate similar to the recalcitrant portions of arthropods observed in this
study. The similarity between estimates of standing
crops calculated from decomposition rates presented
here and those obtained by hand-sorting litter and humus by Cornaby (1973) provides at least limited support for this contention.
The carrion bag method of measuring decomposi-
littei i •
ol leal decomposition. The nylon
mesh m;t- discourage carcass feeders and therefore
decomposition losses are underestimated. However,
undecomposed exoskeleton fragments may simply fall
through the mesh, and rates may be overestimated.
The amount of microbial biomass and elemental content of microbes on and within exoskeleton fragments
was not measured. Seastedt et al. (1980) found fungal
hyphae on and within oribatid mite fragments, and
fungal hyphae were also observed on millipede and
cricket remains. Thus, biomass and elemental concentrations of arthropod remains were likely overestimated.
In spite of these possible biases, our data indicate
that arthropod remains may comprise a significant portion of the total pool of elements such as calcium found
on the forest floor. Canopy arthropods also contribute
exoskeleton fragments and exuviae to this pool of elements. The standing crops of mass and most elements
in arthropod remains appear to equal living standing
crop estimates. Potassium, a relatively mobile element
in forest systems (Whittaker et al. 1979), appears to
be an exception to this rule. McBrayer (1977) and
McKercher et al. (1979) suggested that phosphorus
turnover by arthropods and other invertebrates may
provide a significant fraction of available phosphorus
in soil. Data presented in Tables 2 and 3 suggest that
phorphorus in exoskeleton remains is lost more rapidly than phosphorus in leaf litter. However, other elements such as calcium and magnesium exhibit long
half-lives in exoskeleton remains and are temporarily
unavailable for plant uptake. Thus, in evaluating the
role of arthropods in nutrient cycling of forest systems, the potential for arthropod remains to act as
nutrient sinks deserves consideration, particularly in
forests dominated by heavily sclerotized forms such
as millipedes and orbatid mites.
ACKNOWLEDGMENTS
We appreciate the comments and suggestions of Drs. D.
A. Crossley, Jr. and D. T. Abbott. Elizabeth Blood provided
advice and assistance with nutrient analyses. Research was
supported by National Science Foundation Grant #DEB-7705234- A01 to the University of Georgia (D. A. Crossley, Jr.).
Blood, E. R., and G. C. Grant. 1976. Analysis of cadmium
in fish tissue by flameless atomic absorption with a tantalum ribbon. Pages 1063-1072 in Accuracy in trace analysis:
sampling, sample handling and analysis. Special Publication 422, National Bureau of Standards, Washington, District of Columbia, USA.
Carter, A., and J. B. Cragg. 1976. Concentrations and standing crops of calcium, magnesium, potassium and sodium
in soil and litter arthropods and their food in an aspen
woodland ecosystem in the Rocky Mountains (Canada).
Pedobiologia 16:379-388.
Cornaby, B. W. 1973. Population parameters and systems
models of litter fauna in a white pine ecosystem. Dissertation. University of Georgia, Athens, Georgia, USA.
DECOMPOSITION OF ARTHROPODS
Cromack, K., Jr. 1973. Litter production and decomposition
in a mixed hardwood watershed and a white pine watershed at Coweeta Hydrologic Laboratory, North Carolina. Dissertation. University of Georgia, Athens, Georgia,
USA.
Cromack, K., Jr., P. Sollins, W. C. Graustein, K. Speidel,
A. W. Todd, G. Spycher, Y. L. Ching, and R. L. Todd.
1979. Calcium oxalate accumulation and soil weathering
in mats of the hypogeous fungus, Hystcrungiiim craxsum.
Soil Biology and Biochemistry 11:463-468.
Crossley, D. A., Jr., and D. E. Reichle. 1969. Analysis of
transient behavior of radioisotopes in insect food chains.
BioScience 19:341-343.
Engelmann, M. D. 1961. The role of soil arthropods in the
energetics of an old field community. Ecological Monographs 31:221-238.
Gist. C. S., and D. A. Crossley, Jr. 1975. Feeding rates of
some cryptozoa as determined by isotopic half-life studies.
Environmental Entomology 4:625-631.
Golley, F. B. 1968. Secondary productivity in terrestrial
communities. American Zoologist 8:53-59.
Gosz, J. R., G. E. Likens, and F. H. Bormann. 1973. Nutrient release from decomposing leaf and branch litter in
the Hubbard Brook Forest, New Hampshire. Ecological
Monographs 43:173-191.
Graustein, W. C., K. Cromack, Jr., and P. Sollins. 1977.
Calcium oxalate: occurrence in soils and effect on nutrient
and geochemical cycles. Science 198:1252-1254.
Gray, T. R. G., and T. F. Bell. 1963. The decomposition of
chitin in an acid soil. Pages 222-230 in J. Doeksen and J.
van der Drift, editors. Soil organisms. North Holland Publishing, Amsterdam, Netherlands.
McBrayer, J. F. 1977. Contributions of cryptozoa to forest
nutrient cycles. Pages 70-77 in W. J. Mattson, editor. The
role of arthropods in forest ecosystems. Springer-Verlag,
New York, New York, USA.
McKercher, R. B., T. S. Tollefson., and J. R. Willard. 1979.
Biomass and phosphorus contents of some soil invertebrates. Soil Biology and Biochemistry 11:387-391.
Minderman, G. 1968. Addition, decomposition and accumulation of organic matter in forests. Journal of Ecology
56:355-362.
Moulder, B. C., D. E. Reichle, and S. I. Auerbach. 1970.
Significance of spider predation in the energy dynamics of
forest floor arthropod communities. ORNL-4452, National
Technical Information Service, Springfield, Virginia, USA.
19
Okafor, N. 1966n. Ecology of microorganisms on chitin buried in soil. Journal of General Microbiology 44:311-327.
-.
. 19666. The ecology of microorganisms on, and the
decomposition of insect wings in the soil. Plant and Soil
15:211-237.
Olson, J. S. 1963. Energy storage and the balance of producers and decomposers in ecological systems. Ecology
44:322-331.
Payne, J. A. 1965. A summer carrion study of the baby pig
Sits scrofa Linnaeus. Ecology 46:592-602.
Reichle, D. E. 1969. Measurement of elemental assimilation
by animals from radioisotope retention patterns. Ecology
50:1102-1104.
Reichle, D. E., M. H. Shanks, and D. A. Crossley, Jr. 1969.
Calcium, potassium and sodium content of forest floor arthropods. Annals of the Entomological Society of America
62:57-62.
Seastedt, T. R., and D. A. Crossley, Jr. 1980. Effects of
microarthropods on the seasonal dynamics of nutrients in
forest litter. Soil Biology and Biochemistry 12:337-342.
Seastedt, T. R., A. Kothari, and D. A. Crossley, Jr. 1980.
A simplified gelatin embedding technique for sectioning litter and soil samples. Pedobiologia 20:55-59.
Seastedt, T. R., L. Mameli, and K. Gridley. 1981, in press.
Arthropod use of invertebrate carrion. American Midland
Naturalist.
Van Hook, R. I., Jr. 1971. Energy and nutrient dynamics of
spider and orthopteran populations in a grassland ecosystem. Ecological Monographs 41:1-26.
Veldkamp, H. 1955. A study of the aerobic decomposition
of chitin by micro-organisms. Mededelingen van de Landouwhogeschool te Wageningen/Nederland 55:127-174.
Webster, J. R., and D. A. Crossley, Jr. 1978. Evaluation of
two models for predicting elemental accumulation by arthropods. Environmental Entomology 7:411-417.
White, J., M. Lloyd, and J. H. Zar. 1979. Faulty eclosion
in crowded suburban periodical cicadas: populations out
of control. Ecology 60:305-315.
Whittaker, R. H., G. E. Likens, F. H. Bormann, J. S. Eaton,
and T. G. Siccama. 1979. The Hubbard Brook ecosystem
study: forest nutrient cycling and element behavior. Ecology 60:203-220.
Wiegert, R. G., and F. C. Evans. 1967. Investigations of
secondary productivity in grasslands. Pages 499-518 in K.
Petrusewicz, editor. Secondary productivity of terrestrial
ecosystems. Panstwowe Wydawnictwo Nawkow, Krakowe, Poland.