AN ABSTRACT OF THE THESIS OF
William B. Savidge for the degree of Master of Science in
Oceanography presented on July 18, 1986.
Title:
Factors Affecting the Rates of Infaunal Recolonization of
Small-Scale Disturbances on an Intertidal Sandflat
Redacted for privacy
Abstract approved:
L. Taghon.
Immigration of small benthic invertebrates into two types of
disturbances, small depressions and patches of azoic sand, on an
intertidal sandflat was compared.
Rates of recolonization differed
between disturbances, with numerical recovery in depressions occurring
faster than in defaunated sediments.
The results are hypothesized to
be a consequence of the patterns of sediment transport and deposition
at the study site.
With the exception of capitellid polychaetes there
was no indication of a behavioral response by the Infaunal assnblage
to either disturbance type; colonization appeared to be dominated by
passive advection.
The effects of both disturbance types on faunal
abundances were of short duration.
Disturbancerinduced changes in the
sedimentary environment of depressions were equally transitory.
Factors Affecting the Rates of Infaunal Recolonization
of Small-Scale Disturbances on an Intertidal Sand Flat
by
William B. Savidge
A THESIS
submitted to
Oregon State University
in partial fulfillment of
the requirements for the
degree of
Master of Science
Completed July 18, 1986
Commencement June 1987
APPROVED:
Redacted for privacy
y in charge of major
Redacted for privacy
Dean, College of Oceanogr
Redacted for privacy
School
Date thesi5 15 presented July 18, 1986
TABLE OF CONTENTS
Page
Introduction
Study Site
Method,
Reu1t
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S I I I S S S S S I I S I I S I S I S S S I S S
. . . S S S S I I S I S I S S
Dicuion
Bibliography
Appendic
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S S I S S
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5 5
LIST OF FIGURES
Figure
2
3
Page
Layout of the field experiment. Numbered
rectangles represent locations of individual
experimental plots. Numbered circles indicate
the locations of treatments identified in the
text.
The arrow indicates the predominant
direction of tidal flows at the site.
38
Cumulative mt ill of pit treatments for each
sampling date. Wide bars represent the absolute
amount of sediment inf ill. The bottom of each bar
indicates the mean depth of pits on DO. The top
of each bar indicates the mean depth of pits on
the day on which they were sampled. Narrow bars
represent the ranges of pit depths at formation
(bottom) and sampling (top).
The lines at DO
represent the overall means and ranges of pit
depths at the start of the experiment.
110
Scatter plot of harpacticoid copepod counts from
63 urn and 300 urn screens. Open squares:
controls.
Solid circles:
pit treatments. Open circles:
defaunateci treatments.
Solid line represents the
least squares regression for the pooled data.
112
14
Abundances of total macrofauna, tanaids, spionids,
and harpacticoid copepods. Bars represent mean
numbers per core; lines represent means plus one
standard deviation. Solid bars:
pit treatments.
Open bars:
controls.
Stippled bars:
defaunated
treatments.
5
Abundances of amphipods, cumaceans, oligochaetes,
capitellids, and bivalves. Bars represent mean
numbers per core; lines represent means plus one
standard deviation. Solid bars:
pit treatments.
Open bars:
controls.
Stippled bars:
defaunated
treatments.
146
Sediment data. Wide bars represent means; narrow
bars represent means plus one standard deviation.
Solid bars:
pit treatments. Open bars:
controls.
118
6
LIST OF TABLES
Table
Page
Results of a posteriori multiple comparisons of
Dates are
listed in order of increasing mean rank abundance
for each taxon. Dates not significantly different
at p = 0.05 are underlined. Probabilities listed
animal abundances between sampling dates.
are for the a priori Kruskall-Wallis test.
NS: no significant differences detected by the
a priori test.
2
31
Results of multiple comparisons of proportions of
macrofaunal taxa among treatments. P: pit
treatments. C: controls. D: defaunated
treatments. The treatment having the greater mean
rank abundance in each comparison is listed first.
Dashes indicate no significant differences detected
by a priori tests.
3
33
Results of multiple comparisons of faunal
P: pit/treatments.
C:
controls. D: defaunated treatments. The
treatment having the greater mean rank abundance in
each comparison is listed first. Dashes indicate
abundances among treatments.
no significant differences detected by a priori
tests.
14
314
Results of a posteriori multiple comparisons of
sediment parameters between sampling dates. Dates
are listed in order of increasing mean rank
abundance f or each taxon. Dates not significantly
different at p = 0.05 are underlined. Probabilities
listed are for the a priori Kruskall-Wallis test.
NS:
no significant differences detected by the
a priori test.
5
36
Cctnparisons of sediment parameters between
treatments. P: pit treatments. C: controls.
Dashes denote no significant differences
at p = 0.05.
37
FACTORS AFFECTING THE RATES OF INFAUNAL RECOLONIZATION
OF SMALL-SCALE DISTURBANCES ON AN INTERTIDAL SAND FLAT
INTRODUCTI ON
Biogenic topographic features, such as the pits and mounds
created by the feeding and defecation of infaunal and epibenthic
marine organisms, represent a record of past and continuing
disturbance on the sea floor.
Localized succession within disturbed
patches is thought to contribute significantly to the structure of
benthic assemblages (review by Sousa 19811).
Less often recognized are
the effects of the physical modifications of the benthie environment
which may attend these disturbances (Probert 19814).
As well as representing disturbance in the generic sense &- i.e.
the partial or complete removal of the resident fauna from within a
patch r
small biogenic disturbances may also create localized
alterations in the hydrodynamic flow regime at the sediment-water
Interface (Jumars and Nowell 19811, Nowell and Jumars 1984, Probert
198I, Paola et al. 1986).
Flow around objects protruding from the
sediment, such as animal tubes (Eckman et al. 1981, Carey 1983) or
sediment mounds (Nowell and Jumars 19811, Paola et al. 1986) create
sites of locally enhanced sediment erosion and deposition.
Flow
across depressions in the sediment surface may lead to increased
sedimentation within them (Nowell and Jumars 19811, Jumars and Nowell
1981!, Nowell et al. 19811).
Benthic animals have been shown to respond directly to
2
alterations in flow fields, or indirectly to habitat modifications
induced by local flow regimes.
Flow patterns around sediment
microtopography may enhance microbial or detrital food availability to
benthic animals, indirectly contributing to small-scale aggregations
of organisms in response to higher food levels (Jumars and Nowel).
19814, Eckman 1985, Thistle et al. 1985, Kern and Taghon 1986, Hogue
arid Miller 1981, McL.usky et al. 1983, Thistle 1981, Vanfliaricom 1982,
Grant 1983).
Persistent accumulation of fine particulates within
depressions may create locally differentiated habitats supporting
distinct faunal asemblages (Smith 1980, Braun 1985).
Local concentrations of animals may be formed directly through
the interactions of currents with animals swimming or drifting in the
water colu.
Recent experimental evidence suggests that for small
organisms such as larvae, meiofauna, and juveniles, active movement
may play a minor role relative to passive deposition in determining
where an animal settles (Eckman 1979, 1983; Hannan 19814).
Hannan
(198k) demonstrated that the sinking of larvae of the po].ychaete
Mediomastus ambiseta was qualitatively indistinguishable from
inorganic particles.
Her experiments dealt only with animals in the
water column; the actual process of deposition on the sediment surface
was not examined.
Field experiments by Palmer and Gust (1985) related
the density of sediment-dwelling harpacticoid copepods in the water
column of a tidal creek to the bottom shear stress at the sampling
site.
They noted that the advected fauna consisted almost exclusively
of epibenthic and near-surface forms, and interpreted this to mean
that the meiofauna were being eroded from the sediment and transported
3
passively in the tidal stream (see also Eskin and Palmer 1985).
An
unstated corollary of their conclusions is that advected meiofauna may
be passively deposited on the sediment under the same conditions as
inorganic particles.
Based on a model of purely passive deposition,
Eckman (1983) predicted the immigration rates of advected animals into
experimental tube arrays.
Weak qualitative agreement was found
between predictions and field results f or sane taxa.
However, his
methodology and interpretation have been criticized by Kern and Taghon
(1986).
Eckman (1979), Fiogue and Miller (1981) and Miller-Way (19814)
found correlations between the distribution of meiofauna and juvenile
macrofauna and the spacing of sediment ripples on intertidal sand
flats.
Miller-Way (19814) experimentally manipulated ripple spacing
and found that the horizontal distribution of most taxa (except
nematodes) corresponded to the altered ripple spacing.
She concluded
that the fauna was distributed by the same hydrodynamic patterns which
created the ripple spacing.
Evidence for the passive advection and
deposition of adult macrofauna is largely anecdotal (e.g. Oliver et
al. 1983, 1985).
Many adult macrofauna, particularly crustacea, have
considerable powers of active migration (Alldredge and King 1980), and
may be largely independent of water movement.
If advective transport
of benthic fauna, whether as larvae, juveniles or adults, is an
important vector of colonization of disturbed habitats, then the
characteristics of water and sediment movement in the vicinity of a
disturbance will affect the rates of faunal immigration into the
patch.
This study was designed to evaluate the role of the topography of
4
disturbance on the rates of colonization of benthic fauna.
On the
intertidal sandflats of Yaquina Bay, Oregon, the foraging activity of
seasonally abundant migratory waterfowl creates numerous small
depressions on the sediment surface.
Holes in various stages of
irif ill may cover 2% to 6% of the flat at any one time during the
spring and autumn (unpublished data).
Over large portions of the
flat, pits made by feeding ducks represent the visually dominant
source of topographic heterogeneity on the sediment surface.
are extremely rare.
Ripples
Given that the microtopographic relief
represented by such depressions will interact with near-bottom flows
and the likelihood that small benthic organisms may be passively
advected into new habitats, two interrelated hypotheses were developed
and tested.
First, immigration of animals into small depressions will
proceed more rapidly than into defaunated patches flush with the
ambient sediment surface.
Second, density of immigrants in
depressions will be greater than in ambient sediments.
The
formulation of the hypotheses was based upon the assumption, adopted
from Eckman (1983) that "lateral advection is likely to dominate
recruitment in environments subject to frequent sediment entrainment
and transport, at least among organisms inhabiting surf icial
sediments."
Such conditions are likely to be met on the intertidal
flats on which the study was conducted.
STUDY SITE
This study was conducted on an intertidal sandflat on Yaquina
Bay, Oregon, adjacent to the Mark 0. Hatfield Marine Science Center of
0
0
Oregon State University (klL3k N, 1211.05 W).
The experimental plots
were established at a mid-intertidal location near the center of the
flat approximately one kilometer from shore.
The site was chosen
because it was a physically homogeneous area without conspicuous
mounds or burrows and was rarely disturbed by people digging for clams
or bait.
The sediment at the site is a well-sorted medium fine sand.
The tanaid Leptochella dubia is the dominant macrofaunal organism at
the site.
Small spionid polychaetes are also abundant.
The meiofauna
is dominated by nematodes, harpacticoid copepods, and ostracods.
Birds and small fishes are major predators on the infauna on the flat.
METHODS
Before the initiation of the field experiment, one hundred
experimental plots were laid out at the field site.
Six experimental
treatments were assigned to each plot: a pair of controls
(unmanipulated ambient sediments), a pair of pitted treatments, a
single defaunated treatment, and one sediment bedload trap.
Pitted
treatments were designed to imitate commonly observed natural
depressions on the surface of the Yaquina Bay sandflat, such as those
created by the feeding activities of dabbling ducks (genus Anas) or
the collapse of abandoned animal burrows.
Individual pits were dug by
hand, and were approximately 10-12 cm in diameter, '1-5 cm In depth,
and roughly conical in shape (Figure 1).
Defaunated treatments were
created by digging pits of the same dimensions as the pit treatments
and refilling them with sediment which had been previously collected
from the experimental site, sieved through a 30O-um mesh to remove all
larger animals and detrltal aggregates, and subsequently frozen and
thawed.
Unfortunately, the volume of sediment required to complete a
full set of defaunated treatments was badly underestimated;
consequently only about 2/3 of all experimental plots contained
defaunated treatments.
Treatment locations within experimental plots were assigned in
the following manner:
positions 1, 2 and 3 were assigned randomly to
a control, the defaunated treatment and one of the pit treatments;
position
'1
received a sediment trap; and the second control and second
7
pit treatment were emplaced randomly at positions 5 and 6.
This
arrangement was chosen initially over a completely randomized design
to ensure that treatments being compared directly would be adjacent to
one another, minimizing the influence of spatial variability in
sediment parameters or animal numbers within each plot.
The layout of the field experiment is given in Figure 1.
The
experiment was set up and sampled on May 25, 1985, and sampled again
1, 2, 3, 5, 75, 10.5, 13.5, 19.5 and 23.5 days later.
will be referred to as Dl, D2, D3 ... D23.5.
two tidal cycles.
Sampling dates
Each "day" consisted of
Tides in Yaquina Bay are unequal and semi-diurnal.
Ten plots were randomly pre-assiied for destructive sampling on each
of the ten sampling dates.
In order to minimize sediment disruption
in the vicinity of the experiment, all work on experimental treatments
was performed from boards placed on the sediment parallel to the
plots.
At each plot a sampling template was placed over the marker
stakes and the treatments relocated.
Prior to sampling, the depth and
area of each pit treatment was measured to the nearest 0.25 cm, and
the presence of animal burrows or stranded macroalgae in the sampling
area was noted.
Samples to be analyzed for animal recolonization -
the pit, control, and defaunated treatments in positions 1, 2 and 3
were collected by inserting a truncated 50 cc syringe corer (area:
2
6.16 cm ) to a depth of L0 cm and extruding them into pre-].abelled
Whirl-Pak bags.
A 20 cc core was taken for sediment analysis from
each of the remaining pits and controls (positions 5 and 6).
The
2
corer (area: 2.81! cm ) was inserted to a depth of 1L0 cm relative to
the ambient sediment surface.
After sampling, the sediment cores were
capped with foil and returned intact and in field position to the lab.
On several occasions during the set-up of the experiment some of the
treatments were mis-assigned, with pit treatments being dug in place
of the controls.
In these plots "control" treatments were taken from
undisturbed sediments adjacent to their assigned locations.
Sediment
traps were sampled but not analyzed and will not be considered
further.
Fauna
Upon return to the laboratory, faunal samples were immediately
fixed in a 10% buffered formalin solution and stained with Rose
Bengal.
After fixation, faunal samples were sieved through a 30O-um
Nitex mesh.
The fraction retained on the mesh was sorted into major
taxonomic categories and enumerated at 12x to 32x magnification under
a binocular dissecting microscope.
The remaining material was
transferred to vials containing 70% isopropanol and stored.
The <300-
urn fraction was sieved through a 63-um Nitex mesh and the retained
fraction was placed in vials of 70% isopropanol.
An inspection of the
smaller fraction revealed that a number of juvenile tanaids, spionids
and bivalves passed through the larger mesh.
Consequently the smaller
fractions of the samples were inspected for juvenile macrofauna.
Tanaids were identified to species level.
The majority of the
spionids, capiteflids and bivalves were young juveniles, making their
identification problematical.
Before the faunal data were analyzed, a preliminary regression
analysis of the harpacticoid copepod counts was conducted to see if
numbers of animals retained on the larger sieve was an adequate
predictor of total harpacticoid abundance.
Counts of copepods in the
smaller sediment fraction from a haphazardly selected subset of
samples were regressed against the counts obtained from the material
retained on the 300 urn screen.
The data were log CX +1) transformed
before analysis to meet the equality of variance assumptions of the
2
statistical test (Zar 1971).
An r
of 0.88 was obtained for a power
regression of combined pit, control, and defaunated treatment data
(Figure 2).
Because of the high correlation of harpacticoid counts
from the 63 urn and 300 um screens, statistical analysis of the
harpacticoid copepod data was conducted using counts from the 300
urn
screen.
Sediments
The sediment cores were extruded and sectioned at 1.0 cm
intervals measured from the bottom of the core.
Each section was
0
placed on its own planchette and kept frozen at -20
C until analysis.
The sections from the 20 cc core samples from the pits and controls
were freeze-dried and lightly broken up in a mortar and pestle to
disaggregate the sediment pellet.
The samples were inspected, and all
visible bivalve shell fragments and animal carcasses were removed.
Each sample was split, with half being placed in a pre-weighed
aluminum dish and half in a pre-weighed 15 cc test tube.
After re-
weighing, the dish fraction was burned for eight hours at
0
approximately 1430
C.
The sample was weighed again after cooling, and
the percent weight loss on ignition was calculated.
Pre-tests
10
indicated that the contribution of animal biornass to the total organic
loss was minimal.
The burned sediment was
'ound in a mortar and
pestle and sieved through nested 200'-urn and 63-urn Nitex screens.
After sieving, the sediment fractions retained on each screen were
weighed, and the weight percent of each size fraction was calculated.
The weight of the fraction passing through both screens was calculated
by difference.
The sediment fraction in the test tube was analyzed for
chlorophyll a using a spectrophotometric method modified from Parsons
et al. (1984).
MgCO
To each test tube was added three drops of a 1% (w/w)
solution and 10.0 ml of 90% acetone.
The tubes were sealed with
3
Teflon tape and Parafilm, stirred with a Vortex mixer, sonicated for
one minute, and incubated in the dark for 24 hours in a refrigerator.
The samples were then centrifuged at 1500 rpm for ten minutes to
remove suspended particulates, and absorbances of the acetone extracts
were measured at 750, 665, 664, 647, and 630 nm on a Beckman DU-6
UV/VIS spectrophotometer.
After acidification with HC1 the
absorbances were remeasured.
Concentration of pigment was calculated
from the absorbance values using equations supplied by Parsons et al.
(1984)
Statistical analysis
Because much of the data set did not consistently meet either the
homogeneity of variance or normality assumptions required for
parametric statistical analysis before or after transformation, the
nonr'parametric analogues of the appropriate parametric tests were
11
substituted wherever possible.
The experiment was initially set up to
be analyzed by a twor or three- way randomized block design.
The loss
of a number of data points (e.g. missing defaunated treatments and
individual sediment core sections) precluded the adoption of a multi?-
way statistical design.
Instead, multiple one-way analyses were
performed on the various time and treatment combinations.
As a
result, interactions between time and treatment effects could not be
evaluated statistically.
A significance level of p < 0.05 was chosen
for all statistical comparisons.
Statistical comparisons of animal abundances and sediment data
within treatments among sampling dates were performed with Kruskall?Wa].lis non-parametric ANOVAs by ranks (Zar 197').
The Kruskall-Wallis
test was also used to test for significant differences in faunal
abundances among pit, control and defaunated treatments.
The power of
the Kruskallrwallis test is always at least 95% that of a parametric
one-way ANOVA, and may be of
"eater power than the parametric test
when the assumptions of parametric statistics are violated (Zar 197k).
If significant differences were detected by the Kruskall-Wallis
test, pairwise comparisons were performed using a nonparametric
Tukeyr-type multiple comparison test corrected for ties (Zar 1974).
Where only pit treatments and controls were compared, a two-sided
Mann- Whi tney test was employed
The power of the Mann-Whi tney test i s
approximately 95% of that of a two sample trtest (Zar i974).
Correlations among variables were performed using Spearman's rank
correlation.
12
RES UL1TS
Pit dimensions
Rapid physical recovery of both pit and azoic sediment treatments
was apparent.
By Dl the dark azoic sand of the defaunated treatments
was covered with a thin veneer of oxidized sediment.
The depth of the
oxidized layer increased steadily over the next three and a half
weeks.
Black poorly oxygenated sediment remained visible in deeper
sections of the cores on all sampling dates.
infilling is displayed in Figure 3.
The progress of pit
Although both depth and area of
each depression were measured, estimates of areal coverage of
depressions were complicated by the merging of their boundaries with
low-lying areas of the surrounding sediment.
Inf ill of depressions
was greatest between DO and Di; after Dl mt ill was slower and more
uniform.
Sediment accumulation within pits was a function of both
time and initial pit depth.
Fauna], recolonization :controls
Faunal abundances in control plots were not stable over the three
and a half weeks of the experiment (Kruskall-Wallis test:
p < 0.001).
Mean numbers of total macrot auna per core increased to a peak of 199.6
on Dl from a density of 1L6.3 at the initiation of the experiment.
After Dl mean abundances declined steadily to a low of 76.3
animals
per core on D23.5 (Figure 10. The decline in macrofaunal numbers in
control plots was due almost entirely to siificant reductions in the
abundances of juvenile tanaids and juvenile spionids over time (Figure
13
).
No signif icant differences among dates were detected by Kruskal-
Wallis tests for any other macrofaunal taxon in control treatments.
Abundances of harpacticold copepods were not Included in the macrofauna
counts, even though their size ranges overlapped with that of the juvenile
macrofauna.
spionids.
Their pattern of abundance is similar to that of tanaids and
Harpacticoids also show highly significant differences among
dates in control treatments (Table 1).
Faunal recolonization: pits
Numbers of animals in pit treatments increased rapidly after the
Initial disturbance on DO.
As in controls, the macrofauna in pit
treatments was dominated by tanaids and juvenile spionids.
Significant differences were found among dates for all taxa (Table 1).
Mean total macrofaunal numbers increased from a post-disturbance low
of 27.11 per core on DO to a maximum of 185.9 on D7.5.
No significant
differences were detected by multiple comparison tests between Dl and
D13.5 (range 185.9 to l34.8 per core).
declined rapidly after D7.5 (Figure Z).
Total macrofaunal density
Densities on DO, D19.5 and
D23.5 were significantly lower than on D7.5, and the densities at the
completion of the experiment were not significantly different than
immediately after the disturbance on DO (Table 1).
Three general patterns of recolonization into pit treatments could
be dlscerned.
Juvenile tanaids, juvenile spionids, amphipods and
harpacticoids immignated rapidly into pits during the first three days
of the experiment, reaching peak densities on D2 or D3.
Abundances of
these taxa remained high through the second week of the experiment,
14
after which densities declined.
immigration.
Cumacea followed a similar pattern of
Mean densities increased rapidly during the first three
days of the experiment, but declined to low and constant levels after
D3 (Figures 14 and 5).
The remaining taxa, oligochaetes, capitellids
and bivalves, showed no rapid increase to maximum abundances, but
displayed a slow and fairly steady increase in density in pit
treatment
over the course of the experiment (Figures 14 and 5),
although no siguificant differences among dates were detected after
Dl.
Faunal recolonization: defaunated treatments
The recolonization of the defaunated treatments proceeded quite
differently than in pit treatments.
Total macrofaunal density
increased almost linearly from almost zero on DO to a mean of 11414.8 on
D7.5 (Figure 14).
The few animals present in the defaunated sediment
on DO were probably advected into the treatment during sample
placement.
No early peak in macrofauna numbers could be discerned in
the defaunated treatments.
Immigration of most taxa parallelled that
of the total fauna in defaunated treatments, with a rise to maximum
abundance in the second week of sampling.
Juvenile tanaids and
spionids constituted the majority of colonists.
Capitellids made up a
disproportionately large fraction of early colonists in defaunated
sediments (Kruskall-walljs test: p<O.05) (Table 2).
Between-treatment compari sons
Results of between treatment comparisons of faunal recolonization
15
are summarized in Table 3.
Between treatment comparisons for
individual taxa reveal first that neither pit-digging nor azoic sand
emplacement were either perfectly efficient or equally efficient
defaunatiori procedures.
Samples taken within pits immediately after
formation showed significant reductions in densities of total
macrofauna, tanaids, spionids, oumaceans, oligochaetes and
harpacticoids.
Densities of amphipo4s, capitellids and bivalves were
also reduced in pits, but were statistically indistinguishable from
ambient densities.
All taxa were significantly less abundant in the
azoic sand than in controls.
Pit digging was significantly less
effective at removing amphipods than was emplacing azoic sand.
Harpacticoids, juvenile spionids, cumaceans and tanaids quickly
returned to ambient densities in pit treatments.
Tanaid numbers in
pits were not significantly lower than in controls after Dl.
Spionids
and cumaceans were less abundant in pits than controls only on DO.
Ha.rpacticoid densities in pits were significantly higher than control
densities after one day, and, with the exception of D7.5, remained
significantly greater through D13.5.
No significant differences
between control and pit densities of amphipods, capitellids or
bivalves were found on any date.
Oligoohaete densities were
significantly different only on D3, when control abundances exceeded
pit abundances.
Animals in defaunated sediments took longer to achieve control
densities.
Tanaid, spionid, amphipod and oligochaete numbers were
significantly lower than controls through D5, and, except for
oligochaetes, were also lower on DlO.5.
No significant differences
16
were detected on D7.5; however the mean rank abudances in defaunated
treatments on that date were biased upward by high numbers occuring In
only one or two (of eight) replicate samples taken on that date.
Cunnceans and harpacticoids recovered to control densities by DI.
Bivalve and capitellid numbers were not detectably lower than in
controls on any date.
Only on D13.5 for capitellids did defaunated
treatment abundances significantly exceed controls.
The more rapid colonization of pits than defaunated treatments is
reflected in the significantly lower densities of macrofauna and
harpacticoid copepods in the latter treatment during the first ten
days of sampling (Figures 4 and 5, Table 3).
Only capitellids, on
D1O.5, were significantly more abundant in defaunated treatments than
in pit.,.
The recolonization of most macrofauna]. taxa into disturbed
treatments occurred in proportion to their abundances In the
surrounding sediments (Kruskal-Walljs test).
Although scattered
differences among treatments were found for several taxa, only the
proportion of capiteflids in defaunated treatments showed any
consistently significant deviation from controls (Table 2).
Very few significant correlations (Spearman's r:
p<.05) were
found among taxa within treatments or among treatments for any taxon.
These results justify the choice of single variable rather than paired
sample statistical tests for the faunal data (e.g. employing the MannWhitney test rather than the Wilcoxon test, its paired sample
analogue).
Cumaceans were the only taxon to show consistent
correlations among treatments.
They accounted f or 11 of the 21!
17
positive correlations observed out of a possible total of 216
(exclusive of DO).
Correlations between taxa within treatments were
rare, and did not indicate any consistent patterns of corabundance
between species pairs.
Positive correlations between taxa were found
in I5 out of 756 comparisons, exclusive of DO.
were found in four Instances.
Negative correlations
The frequency of significant positive
correlations Is not much greater than would be expected by chance
alone.
Animal-pit relationships
The relationship between pit infilllng rate and faunal
immigration rate was assessed by correlating the depth, area and
volume of depressions with the number of animals present In them.
Because the greatest amount of Inf ill and the largest Influx of
colonists occurred between DO and DI, the correlation was performed on
the Dl data.
Animal numbers were normalized by subtracting the
numbers of individuals of each taxon collected from IndIvidual pits on
Dl from the mean number (N1O) of that taxon present In controls On
Di.
No significant correlations were found between faunal
recolonization and any measure of changes in pit dimensions between DO
and Di, with the exception of cumaceans, which displayed a significant
positive correlation (Spearman's r:
p - O.01fl) with the ratio of pit
depth on Dl to initial pit depth.
Sediment parameters
No changes In surf icial sediment parameters were detected in
18
controls over the course of the experiment (Table 11).
Small mineral
grains (<63 urn) made up between 111.0% and 17.9% of control sediments
by weight.
Organic matter, measured as percent loss on ignition,
ranged from 2.05% to 2.32%.
The mean concentration of chlorophyll a
varied between 17.116 ug/g and 20.78 ug/g of sediment.
A ratio of 110:1
has been suggested as an approximate conversion of plant biomass to
chlorophyll (Cammen and Walker 1986, but see deJonge 1980), implying
that living plant material cc*nprosed roughly 3% to 11% of the total
organic matter in the sediment at the study site.
In pit treatments few statistically significant differences in
sediment parameters among sampling dates were detected (Table 14).
No
obvious trends in the data could be discerned.
Between-treatment comparisons revealed that pit treatments
contained consistently higher concentrations of organic matter (as
both chlorophyll a and total combustible material) than did controls
(Figure 6).
The percent loss on ignition of' sediments fran pits was
significantly greater than from controls on D3, D7.5, D10.5, D13.5,
D19.5 and D23.5 (Table 5); chlorophyll content was significantly
higher on Dl, D2, D3, D7.5 and D13.5 (Mann-Whitney test:
p<0.05).
No
differences in grain size were found between treatments.
Animal-sediment relations
Mean concentrations of chlorophyll a and mean faunal abundances
on all sampling dates were correlated to see if there was any
statistical relationship between food abundance and animal densities
within treatments.
No significant correlations were found in control
19
treatment5 f or any taxon.
In pit5 a $ignif leant positive correlation
was found for spionid abundances (Spearman's r = 0.7625, p < .02), and
a significant negative correlation was found for eapitellid numbers (r
rO.779, p < 0.02).
20
DISCUSSION
Differences in the rate of accumulation of animals in pitted and
defaunated treatments provides circumstantial evidence for both active
and passive modes of immigration into small disturbances.
The
relatively rapid increase in density of capitellids in defaunated
treatments, and their significantly higher proportional abundance on
D3, D5, D1O.5 and D13.5 are contrary to predictions based on a
primarily passive mode of immigration.
It is likely that capiteflids
migrated actively Into azoic sediments, although it is unclear whether
their response represented opportunism or was a consequence of the
experimental design.
The defaunated treatment placed a cap of poorly
oxygenated and non-bioturbated sediments over deeper sediments,
limiting the supply of oxygenated water frcrn the surface.
Although
the depth distribution of the fauna at the study site was not examined
directly, it is evident that sane capitellids live at depths greater
than 1L0 cm beneath the sediment surface, because cores taken fran
freshly dug pits did not show significant reductions of capitellid
numbers relative to the upper four centimeters of control sediments.
These deeper living animals may have migrated upward into the
defaunated treatments in search of a better oxygenated habitat.
Alternatively (or additionally), juveniles, which made up the majority
of capitellids collected from all treatments, may have been attracted
to the defaunated treatments by a sulfide cue.
Hydrogen sulfide may
induce settlement in the larvae of Capitella capitata sp. I (Cuomo
21
1985), and juvenile and adult capitellids may possess a similar
response.
Thrush (1986) noted high densities of capitellid
polychaetes in anoxic sediments beneath small mats of decaying
seaweeds, and the more general association of capitellids with
disturbed, organically enriched and poorly oxygenated sediments is
well documented (Pearson and Rosenberg 1978).
After DO no sulfide-
rich sediment was visible at the surface, but low concentrations of
sulf Ides emanating from beneath the oxygenated layer may have been
detectable by the worms.
The opposite view may also be taken that the relatively high
rates and high proportions of capitellids Invading defaunated
treatments does not represent so much a selection of the sediment by
capItellids as its avoidance by other taxa.
However, with the
exception of aznphlpods and cumacea on Dl and amphipods on D5, no
species was proportionally less abundant in defaunated treatments than
in pits or controls.
It seems unlikely that all other taxa at the
experimental site display an equal aversion to suif ides, making
selection of the defaunated treatments by caplte].lids, not avoidance
by other infauna, the more parsimonious interpretation of the
colonization of the sediments.
The more rapid immigration of taxa other than capitellids into
depressions may have been due to active selection of pit sediments in
response to higher food abundance there.
VanBiaricom (1982), Thistle
(191) and Oliver et al. (1983, 1985) have suggested that some early
colonists in natural disturbances (pits) in subtidal habitats may
actively seek and exploit food resources made available by the
22
disturbance.
There was a significant correlation between chlorophyll
a and spionid densities in pit sediments, but not in controls.
The
abundance of no other taxon was correlated with sediment organic
(.'food') content.
Unfortunately, no direct measurements of sediment
organic levels levels were made in defaunated treatments.
Davis and
Lee (1983) monitored microalgal recolonization in field experimental
sediments virtually identical to the defaunated treatments employed
here and found that chlorophyll a concentrations in surface sediments
recovered to ambient control concentrations within ten days, the first
date on which they collected samples.
It may be assumed that during
the initial week of colonization food concentration (as chlorophyll a)
in defaunated treatments was lower than in pits.
Without further experimentation an active response to increased
food availability in pits can not be rejected as an explanation of the
relative rates of colonization of pit and defaunated treatments,
although there are reasons to doubt its validity.
If food is
responsible for a'egation of animals in experimental treatments,
then it would be reasonable to assume that higher concentrations of
food in ambient sediments would be correlated with higher faunal
densities.
Such is not the case; nor is there a significant
correlation between animal densities and chlorophyll when both
controls and pits are considered together.
A more likely explanation
for the co-occurence of higher densities of food and fauna in pits
than in controls is that detritus, microalgae and animals are
concentrated independently within depressions.
Nowell and Jumars
(198Z) used similar reasoning to explain the simultaneous presence of
23
early colonists and high concentrations of organic matter in
depressions formed by the feeding activities of rays (VanBiaricom
1982), suggesting that both animals and detritus are aggregated
passively in the bottoms of the depressions by currents.
Evidence for a primarily passive mode of dispersal into the
experimental treatments can be found first In the rejection of the
null hypothesis that immigration into pitted and nonrpitted defaunated
sediments will be equivalent.
Both treatments covered approximately
equal surface areas at the initiation of the experiment, and would
have experienced an equal flux of sediment bedload over their
surfaces.
Because of the reduced shear stress encountered by the
sediment/animal/fluid mixture of the bedload as It was advected over
the pit treatments, some of the material would have settled out of
suspension and accumulated In the bottoms of the depressions.
Material passing over the surfaces of the defaunated treatments would
have experienced no such reduction In shear stress, and less suspended
material would have been deposited on them.
In addition, animals and
sediments deposited within depressions would have experienced a lower
probability of resuspension than in defaunated treatments.
The Increased abundances of tanaids, splonids, ainphipods,
cumaceans and harpacticoid copepods in pits coincided with a greater
net accumulation of advected sediments in pits than In defaunated
sediment patches, particularly between DO and Dl when the amount of'
sediment suspended in the water column was apparently very high as the
result of a strong windstorm at the beginning of the experiment.
The
large quantity of sediment deposited between DO and Dl was probably
24
the result of the interaction between the large flux of suspended
sediment and bedload over the depressions with the greater trapping
efficiency of the deep, newly dug pits.
Significantly, four of the
five taxa are small surface dwelling forms that are potentially
subject to entrainment into the water column by erosive bottom shear
stresses.
Mendoza (1982) noted that Leptochelia dubia is easily
dislodged from the sediment by simulated wave action.
The juvenile
spionids present at the study site at the time of the experiment were
too small to build deep or robust tubes in the sediment, and were
probably similarly susceptible to disturbance by waves.
Harpacticoid
copepods, because of their small size and epibenthic habits, are also
capable of being entrained and advected by currents (Palmer and Gust
1985, Eckman 1983, Riedenauer and Thistle 1983, Kern and Taghon 1986).
Cumaceans, which displayed higher densities and more rapid
recolonization of pits than defaunated treatments, are active on the
sediment surface, and can often be seen swimming in the shallow pools
left on the flat by the retreating tide (personal observation). The
life habits of the ainphipods at the study site are unknown.
They may
be tubicolous or shallow burrowers; the compact shape of most
individuals suggests the latter.
Small sediment dwelling amphipods
may by eroded from sediments and transported passively (Grant 1980,
1981), but most are also competent swimmers (e.g. Grant 1981,
Alldredge and King 1980).
Ideally, the rates of immigration of actively swimming or
crawling animals will be independent of the bottom shear stress and
sediment transport, and are dependent upon the density of animals in
25
the water column and the relative attractiveness of different
substrates.
All e].se being equal, the rates of faunal immigration
into the two experimental treatments should have been roughly
equivalent.
Hovever, all things are never equal, and the two
treatments were probably perceptibly different physically and
chemically to the immigrating animals, thus affecting the relative
rates of active immigration into the two treatments.
Moreover, small
actively swimming animals are unlikely to be completely independent of
water motion.
Animals swimming over depressions may experience a
higher probability of contact with the sediment because of the reduced
shear stress there relative to the ambient sediment.
Unlike passively
deposited animals, however, active migrants have a greater capacity to
emigrate fromunfavorable habitats.
Low abundances and inefficient defaunation procedures made it
impossible to estimate statistically the recolonization rates of
capitellids, oligochaetes and bivalves into the experimental
treatments.
When the data are considered qualitatively, it is
apparent that the absolute rates of increase are low for capitellids
in pit treatments and for oligochaetes in both pit and defaunated
treatments relative to the increases observed f or surface dwelling
taxa such as tanaids and spionids.
Because capitellids and
oligochaetes burrow well beneath the sediment surface, they were
probably protected from erosion and transport by near-bottom flow.
Burrowing through the sediment was probably the predominant mode of.
influx into pit and azoic treatment sediments for those taxa.
more rapid influx of surface dwelling taxa into experimental
The
26
treatments suggests that active immigration or passive drift through
the water column are more efficient modes of colonization than benthic
crawling, even for small disturbances.
The second hypothesis, that pits would accumulate significantly
higher densities of animals than ambient controls, could not be
accepted for the macrofauna, although the numbers of harpacticoid
copepods in pits were significantly higher than in controls or
defaunated treatments from Dl through D13.5.
Qualitative agreement
with the hypothesis (higher means in pits, but not significant at the
p
0.05 level) could be seen for tanaids, bivalves and total
macrofauna.
Three potential explanations may be put forward.
First,
of course, is the possibility that passive deposition of animals into
small sedimentary depressions is not an important vector of
colonization of small infauna.
However, the relative rates of
colonization into the two disturbance treatments implies that it is,
at least f or some fauna.
Second, the depressions created may not have
been persistent enough to permit significantly higher numbers of
animals to be deposited.
The trapping efficiency of depressions
undoubtedly decreases at progressively shallower pit depths, but even
very shallow pits were observed to collect higher concentrations of
organicmineral aggregates than the surrounding sediment surface at
low tide.
Controlled flume experiments in the laboratory are required
to assess the relative trapping efficiencies of different depression
configurations.
Decreasing collection efficiency over time would
theoretically tend to slow, but not halt, the rate of passive
accumulation of small infauna, leading to an asymptotic rise of
27
animals to a maximum abundance as pits fill in.
Such a pattern was
not displayed by any of the taxa identif led as potential passive
immigrants (tanaids, spionids and harpacticoid copepods).
The
Initially rapid rise in faunal density in pit treatments is consonant
with the passive accumulation hypothesis; the subsequent decline in
numbers over the final three to five sampling dates is not.
Third,
increased predation at high faunal densities within pits may have
prevented abundances from significantly exceeding controls.
Field
observations during sampling revealed that a large number of epifaunal
predators were present on the flat at the time of the experiment.
Juvenile staghorn soulpin, Leptocottus armatus, were particulary
common, and are known to feed on tanaids (Mendoza 1982) and amphipods
(Smith 1980).
By concentrating food resources, pits may have
represented preferred foraging sites for small predators.
VanBiaricom
(1982), Nerini and Oliver (1983) and Oliver et al. (1983, 1985) have
noted the attraction of epibenthic predators to recently formed
depressions.
As infaunal densities in pit treatments approached
control densities, they may have attracted higher numbers of
predators.
Increasing predation pressure at higher infaunal densities
may have prevented pit abundances from exceeding controls, even if the
depression., continued to accumulate bedload and drifting animals.
The
observed declines in controls and defaunated treatments may also be
attributable to predation.
Small-scale disturbances on the sea floor can not be treated as
"black boxes" for which patterns of recolonization are a function of
the life histories and behavior of immigrating organisms.
Conditions
28
both internal and external to the disturbed patch interact with the
pool of potential colonists to affect the rate of colonization and
taxonomic composition of the immigrating fauna.
Smith (1985) has
compared the response of the deep-sea benthos to different types of
disturbances on the sea floor.
Patterns of faunal response were
profoundly dependent upon the type of disturbance considered.
The
disturbances considered by Smith (1985) (food fall and trays of frozen
and thawed sediments) represent rare and extrane forms of disturbance,
and the faunal responses were not likely to be typical of most natural
disturbances in the deep sea.
However, his results do point out the
influence that the source of the disturbance may have on faunal
recovery patterns.
In contrast, Pearson and Rosenberg (1978) noted
that many of the species which are among the first to colonize
disturbed polluted sediments in shallow water are also among the first
to exploit "clean" disturbances such as dredged bottoms or spoil
banks.
The results of the present experiment suggest that the
relative rates of immigration into different types of disturbance
(here depressions and frozen and thawed sediments) are largely a
function of the microenvironment of the disturbed patch.
The higher
rates of immigration of surface dwelling juvenile macrofauna and
harpacticoid copepods into depressions can be related to differences
in the topography and flow regime within each treatment.
Differences
in the colonization rates of capiteflid polychaetes, and perhaps to a
lesser extent other taxa, are probably a function of selection or
avoidance of treatment sediments on the basis of some physical or
chemical cue.
In contrast, the absolute rates of advective
29
colonization, and the maximum faunal densities within disturbed
patches, were determined by conditions independent of the disturbance
and the colonizing fauna.
The rate o.f net accumulation of surface'-
dwelling taxa was probably related to the intensity of sediment
transport on the flat at the time of the experiment.
The potential
attractiveness of disturbed patches to colonizing animals appeared to
be of lesser significance.
Kern and Taghon (1986) also observed that
the number of harpacticoid copepod colonizing small experimental
treatments was a function of the absolute magnitude of sediment
transport at the site.
In this experiment, maximum densities of
animals within the treatment sediments did not appear to be related to
food availability or any other measured environmental parameter within
pits or defaunated treatments.
The relative Importance of advective colonization is likely to be
highly variable both spatially and temporally.
The magnitude of
passive immigration into disturbed patches will depend upon the
interactions among sediment flux at the site of the disturbance, the
net accumulation of advected bedload, and the susceptibility of
members of the ambient ccmmunity to entrainment and transport in the
water column.
Except in surf zones, sediment transport is an
intermittent phenomenon (Grant 1985).
In most habitats passive
colonization by adults and juveniles will be an episodic event
superimposed upon a background of active colonization (e.g. Rees et
al. 1978).
In this experiment, because of the overwhelming dominance
of newly recruited juveniles at the study site, the entire guild of
small surface depositfeeding infauna were indiscriminately advected
30
into experimental treatments.
Less severe sediment transport or a
more heterogeneous size structure of the community may result in Only
a limited subset of the ambient fauna being advected and accumulated
in depressions, allowing distinct assemblages to be formed within
them.
31
Table 1.
Re5ult
of a posteriori multiple comparisons of animal
abundances among sampling dates.
Dates have been rounded to whole
numbers and are listed in order of increasing mean rank abundance
for each taxon.
underlined.
Dates not significantly different at p
0.05 are
Probabilities are given for the a priori
Kruskall-Wallis tests.
a priori testing
NS:
no significant differences detected by
Table 1.
C1ITR0L
PIT
IThFAIJNATED
TOTAL
MACROFAUNA
TANAIDS
SPIONIDS
23
19
23
13
19
23
19
0
13
0
10
10
1
10
NIPHIPODS
13
7
5
3
2
2
3
1
2
5
5
1
3
1
p(O.001
0
23
19
1
5
2
10
p(O.00I
0
23
19
5
1
3
13
p<0.0Ol
0 23
19
5
10
3
0
23
19
1
7
0
23
19
7
13
0
2
5
1
30
3
0
2
3
0
1
3
5
0
19
MS
CUMACEANS
MS
OLIGOCIIAETES
MS
CAPITELLIDS
MS
BIVALVES
HARPACTICOIDS
0
7
MS
39
0
13
23
3
5
10
2
7
1
pC.O.001
23
1
2
5
10
3
1
p(0.O01
0
1
2
23
3
2
10
7
pC0.001
0
2
1
23
19
7
13
2
p<0.O0l
0
I
2
3
10
13
3
p(0.00J
0
I
5
10
2
3
p<O.00l
0
19
13
5
1
13
7
39
23
33
p<O.OlS
0
3
3
2
7
30
5
39
23
13
p<O.OI
0
1
2
23
7
2
19
10
23
13
p<0.Ol5
0
1
2
5
7
5
1
p<O,00I
0
3
19
2
3
10
10
13
7
p(fl.00I
3
5
30
13
7
p<0.00I
19
10
7
13
pCO.00I
3
23
13
7
p (0.001
19
23
19
2
7
5
3
19
7
5
3
10
pO.O5
23
19
13
pO.003
7
10
13
p(O.0I
10
23
13
pO.O25
7
p(0.005
5
7
10
5
3
1
5
5
2
1
3
33
23
19
23
2
10
13
33
Table 2.
Results of multiple comparisons of proportions of
macrofauna among treatments.
D:
defaunated treatments.
P:
pit treatments.
C:
controls.
The treatment having the greater mean
rank abundance in each canparison is listed first.
Dashes
indicate no si&iif leant differenes detected by a priori tests.
SAMPLING DATE
tanalds
0
1
-
-
2
3
5
7.5
-
10.5 13.5 19.5 23.5
-
C= P
DP
spionids
D-C
P-C
PI.0
amphipods
cumacea
oligochaetes
P>D
C-D
C>P
D-P
C-D
r
r
P>D
-
P>D
P-C
P>D
C>D
C-P
D-P
r
D-C
capitellids
bivalves
F
C-P
D>P
D-C
D>C
P>C
D=P
D>C
-
-
-
C-P
D>P
-
-
C-P
D>P
D>C
P-C
D>P
D>C
-
-
34
Table 3.
Results of multiple comparisons of faunal abundances
among treatments.
C:
controls.
F:
pit treatments.
D:
defaunated treatments.
The treatment having the greater mean rank abundance
is listed first.
by a priori tests.
Dashes denote no significant differences detected
35
Table 3.
SAMPLI IG DA FE
total
macrofauna
tanald5
spion1d
ainphipod
0
1
C>?
C> P
P=D
C>D
P. D
C> P
C> P
P=D
2
3
5
7.5
10.5 13.5 19.5 23.5
C-P
P>D
P-C
P- D
P-C
P>D
P-C
P-C
P-D
C>D
D-C
C>D
D=C
P>D
C=D
P
C-P
P>D
C>D
P>D
C>D
C- P
P>D
P-C
C-P
P-C
P-C
P=D
P>D
P=D
P>D
C>D
C>D
C>D
C>D
C>D
P= D
D=C
C>P
C-P
C-P
C=P
C-P
P-D
C-P
P-D
P>D
P-D
C>D
C>D
P>D
C>D
C>D
C>D
P>D
C>D
C-P
P-C
P>D
C-P
P-D
C-P
P>D
P>D
C=P
P>D
C>D
C>D
C>D
C>D
C>D
C>D
C=I
-
r
-
-
C>D
C-P
PD
C>D
C>P
cumacea
P-D
-
-
C>D
C>P
C-P
C-P
P-D
C-P
P-D
P-D
C>D
C>D
C>D
P>D
C>D
P>D
C>D
C>P
oligochaete3
capitellld3
C-P
P-D
r
i
C-D
C-P
b1valve
harpactcoids
P=D
C-D
-
-
C-P
P-C
D>P
D-C
D'P
P-C
-
P>D
D>C
r
-
C=D
C>P
P=D
P-C
P>C
P>D
P>C
P>D
P=C
P>D
P-C
P"D
P>C
P>D
C>D
C-D
C-D
C-D
C-D
C=D
D-C
P-D
36
Table
.
Results of a posteriori multiple comparisons of
sediment parameters among sampling dates.
Dates have been rounded
to whole numbers and are listed in order of increasing mean rank.
Dates not significantly different are underlined.
Probabilities
are for the a priori Kruskall-Wallis test.
NS:
no significant differences detected by a priori testing.
CONTROLS
Chlorophyll a
NS
Percent loss
on ignition
NS
Weight percentage
fine particulates
NS
P ITS
Chlorophyll a
10
19
23
Percent loss
on ignition
Weight percentage
fine particulates
5
13
2
3
7
1
p < 0.02
NS
5
2
3
1
23
19
7
10
13
p < 0.02
37
Table 5.
Comparisons of sediment parameters between treatments.
P: pit treatments.
controls.
C:
differences at p - 0.05.
(ug/g).
Grain:
Percent LOl:
Dashes indicate no siiif leant
Chi a: Concentration of chlorophyll a
percent weight loss of sample on ignition.
Weight percentage of mineral grains passing through a 63 urn
sieve.
SAMPLING DATE
Chi a
Percent LOl
Grain
1
2
3
5
7.5
P>C
P>C
P>C
r
P>C
P>C
P>C
10.5
13.5
19.5
P>C
P>C
-
P>C
23.5
-
P>C
P>C
38
Figure 1.
Layout of the field experiment.
Numbered rectangles
represent the locations of individual experimental plots.
Numbered
circles indicate the locations of experimental treatments identified
in the text.
The arrow indicates the predominant direction of tidal
flows relative to the experimental site.
/
39
Figure :1
1P
1042
.
1.z.
riJ r921
1T99JdOOi
roi rai
r7Bi P711 [7ii
5.o
T311
EBB
1301r291
L1iJr17i
TiTT3
4I
FLOOD
40
Figure 2.
date.
Wide bars represent the absolute amount of inf ill by
sediment.
on DO.
Cumulative inf ill of pit treatments for each sampling
The bottom of each bar indicates the mean depth of pits
The top indicates the mean depth of the same pits on the
day on which they were sampled.
Narrow bars indicate the ranges of
pit depths at formation (bottom) and sampling (top).
The lines at
DO indicate the overall mean and range of depths of pits at the
start of the experiment
CD
'1
i-I.
TIJT
IEI-
C
C
C
I
-
11-
S
C
I
C
I
I
C
I
C
-
C
I
(cm) SURFACE SEDIMENT THE TO RELATIVE DEPTH
42
Figure 3.
and 300 urn
treatments.
Scatter plot of harpacticoid copepod counts from 63 urn
creen.
Open
Open circles:
quare:
controls'.
Solid circles:
defaunated treatments.
Solid line
represents the 1eat quare regression for the pooled data.
pit
43
Figure 3
3.5
3.0
w
2.5
0
I-
LU
C'-,
-
1
le.
IC.-,
0
Li..
100
+
0.5
0.0
0.5
100
105
2.0
2.5
LOG(X+1) OF HARPACTICOIDS RETAINED ON A 300um SCREEN
44
Figure
.
Abundances of total macrofauna, tanaids, spionids, and
harpacticoid copepods.
Bars represent mean numbers per core; lines
represent means plus one standard deviation.
treatments.
treatments.
Open bars:
controls.
Solid bars:
Stippled bars:
pit
defaunated
Figure 4
fauna
100.0
h
Tanaids
I
Spionids
4
150.0
Harpacticoids
1i
0
1
2
3
5
7.5
10.5
13.5
Sampling Date
19.5
23.5
Is
46
Figure 5.
Abundances of amphipods, cumaceans, ollgochaetes,
capitellids, and bivalves.
Bars represent mean numbers per core;
lines represent means plus one standard deviation.
pit treatments.
treatments.
Open bars:
controls.
Solid bars:
Stippled bars:
defaunated
Figure 5
15.0 T
10.0
Amphipods
5.Of
6
0.0
40.0 j
30.0 1
Cumaceans
200
I
10.0
0.0
25.0
20.0
Oligochaetes
H
15.0
10.0 1
5.0 [
0.0 1
Capitellids
10.0
1.
5.0
1
0.01
IJ
10.0
Bivalves
5.0 F
0
1
2
3
7.5
1C.5
13.5
Sampling Date
19.5
23.5
48
Figure 6.
Sediment data.
Wide bars represent means; narrow bars
represent means plus one standard deviation.
treatments.
Open bars:
controls.
Solid bars:
pit
Yigure 6
prg:edrnnt
Ii
eren1oss
1tiiIiIi
13 13
o
1
2
3
5
7.5
10.5
13.5
Sampling Date
19.5
23.5
50
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1985.
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1984.
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1981.
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1980.
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198)4.
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1982.
Sane aspects of the autecology of Leptochelia
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1983.
Gray whales and the structure
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Macrobenthic succession in
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19811.
A Manual of Chemical
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New York, 173 pp.
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1980.
Seasonality, Spatial Dispersion Patterns and the
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1985.
Colonisation studies in the deep-sea:
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5111 pp.
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19811.
The role of disturbance in natural communities.
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1981.
Natural physical disturbances and communities of
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An
experimental investigation of enhanced harpacticoid (Copepoda)
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63, 295r299.
53
Thrush, S. F.
The sublittoral macrobenthic community structure
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1986.
VanBLaricom, G. R.
1982.
Experimental analyses of structural
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197'I.
Biostatistical Analysis,
Cliffs, N. J., 718 pp.
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APPENDICES
54
Appendix 1:
Speetrophotanetric equations for calculations of
pigment concentrations in sediment samples (modified from Parsons
et al. 198k).
of 66k run.
E665o
acidification.
absorbarice of the sample at a wavelength
E6611
absorbance of the sample at 665 run before
E665a
absorbance at 665 run after acidification.
Al]. absorbance readings were corrected for turbidity by
subtracting a blank absorbance read at 750 rim.
Chlorophyll a:
ii.85(E6614)
1.511(E6k7)
0.08(E630) = A
ug Chl a/g sed - A/g
Chlorophyll b
21 03(E6117)
5 143(E66k) - 2 66(E630) = B
ug Chl b/g sed - B/g
Chlorophyll C:
2k.52(E630) r
i.67(E66k) r 7.6(E6147) = C
ug Chi c/g sed - C/g
Total carotenoids:
7.6(Ek80
1.k9(E510)
TC
ug Car/g sed = TC/g
Phaeopigments:
267 * (E665o r E665a) = P
ug Phaeo/g sed = P/g
55
Appendix 2.
Raw data and regression equation for harpacticoid
copepod counts from 63 urn and 300 urn sieves.
log(X + 1)
(X)
> 300 urn
< 300 urn
> 300 urn
< 300 urn
CONTROL
16
131
1.230
2.121
373
1.531
2.573
62
892
1146
1353
857
578
785
1.799
2.053
2.851
112
33
1414
39
111
111
3.060
3.132
2.933
2.763
2.895
2.161
1.602
1.623
1.623
PIT
3
87
149
115
1546
1238
0.602
2.176
1.91414
72
'921
12k
55
56
11314
1.863
2.097
3.189
3.093
2.965
3.055
783
1.7148
2.8914
8714
1.756
2.9142
2.0614
DEFAUNATED
2
53
0.1477
1.732
13
29
293
1.1146
1.1477
2.1468
73
95
871
702
51
1296
66
1116
7113
2.872
1.869
1.982
1.716
1.826
2.9141
2.8147
3.113
2.620
.39071
Regression equation:
Y = 2.3014814 * X
2
r
= 0.88
56
Appendix 3.
Raw fauna]. data from control cores.
standard deviations for each taxon are given.
Means and
= missing data.
DAY 0
STA
TAN
SPION
AMPH
CUM
3
175.0
14
1145.0
37.0
30.0
15.0
18.0
18.0
11.0
5.0
2.0
0.0
3.0
0.0
5.0
214.0
9.0
16.0
26.0
19.0
L.0
11
614.o
61
83.0
102.0
51.0
95.0
80.0
55.0
53.0
66
68
71
93
914
99
21.14
90.3
(141.3)
(
7.8)
2.0
12.0
14.2
(3 8)
OLIG
CAP
BIV
HARP
1.0
7.0
3.0
2.0
10.0
31.0
0.0
3.0
2.0
0.0
5.0
0.0
0.0
27.0
57.0
33.0
16.0
33.0
10.0
6.0
'4.0
0.0
2.0
12.0
15.0
34.0
21.0
9.8
(10 9)
19.0
13.0
11.0
20.0
20.0
29.0
16.2
(
9 3)
1.0
2.0
14.0
2.0
3.0
0.0
5.0
14.0
2.14
(1
7)
14.0
3.0
3.0
1.0
2.0
142.0
47.0
140.0
21.0
2.0
32.6
(1 7)
(114 5)
BIV
HARP
1.0
72.0
DAY 1
STA
TAN
SPION
8
32
38
1314.0
140.0
8.0
182.0
140.0
914.0
33.0
14.0
6.0
10.0
11.0
9.0
AMPH
OLIG
CAP
6.0
9.0
14.0
15.0
3.0
1.0
1.0
1.0
0.0
1.0
2.0
1.0
1.0
2.0
CUM
514
1148.0
314.0
2.0
2.0
3.0
55
59
65
1142.0
1146.0
35.0
7.0
146.0
2.0
101.0
147.0
2.0.
5.0
7.0
6.0
80
1147.0
3.0
13.0
88
138.0
121.0
32.0
32.0
3.0
8.0
140.0
0.0
5.0
3.2
6.8
(2.9)
97
135.3
(25.2)
37.9
(
5.6)
(2.14)
12.0
7.0
32.0
32.0
6.0
13.9
(
9.9)
1.3
(0.8)
2.0
147.0
1.0
3.0
0.0
0.0
132.0
60.0
39.0
71.0
0.0
149.0
3.0
0.0
1.0
140.0
1.1
(1.2)
67.0
72.0
614.9
(26.9)
57
Appendix 3. (continued)
DAY 2
STA
TAN
SPION
AMPH
CUM
OLIG
CAP
BIV
HARP
5
161.0
153.0
32.0
25.0
0.0
0.0
2.0
117.0
3.0
1.0
76.0
62.0
52.0
81
1114.0
92
103.0
39.0
27.0
37.0
37.0
32.0
51.0
26.0
11.0
67
83.0
58.0
199.0
163.0
110.0
19.0
10.0
11.0
17.0
115.0
214.0
2.0
7.0
21.0
11.0
50.0
3.0
18.0
1.0
143.0
5.0
16.0
3.0
11.0
9.0
7.0
13.0
0.0
0.0
112.0
65.0
1.14
12
15
17
214
37
62
118.7
(149.9)
(
33.0
8.3)
3.0
3.0
4.0
10.0
6.0
12.0
7.6
13.8
23.0
6.0
13.0
13.0
15.0
8.0
0.0
5.0
5.0
2.0
1.0
2.0
8.0
3.0
6.0
2.0
2.0
1114.0
55.0
211.0
13.5
3.3
(2.6)
(i.'4)
58.2
(23.6)
CUM
OLIG
CAP
BIV
HARP
4.0
11.0
14.0
39.0
0.0
0.0
2.0
1.0
1.0
5.0
5.0
3.0
(4.6) (14.2)
(
5.2)
DAY 3
STA
TAN
SPION
AMPH
19
28
158.0
39.0
19.0
31
169.0
35
1140.0
6.0
11.0
5.0
0.0
7.0
16.0
2.0
1145.0
86.0
101.0
97.0
26.0
69.0
88.0
614
89
90
91
95
100
108.2
(
1414.6)
311.0
314.0
37.0
19.0
149.0
29.0
147.0
37.0
311.11
(10.1)
3.0
3.0
5.0
7.0
10.0
6.0
10.0
12.0
57.0
16.0
114.0
3.0
13.0
611.0
6.6
18.0
(5.2) (22.9)
17.0
31.0
16.0
****
5.0
(
11.6
9.3)
14.0
0.0
3.0
14.0
2.14
(1.8)
0.0
1.0
1.0
1.0
3.0
7.0
0.0
2.0
1.0
2.1
(2.3)
214.0
140.0
63.0
117.0
142.0
1414Q
65.0
69.0
514.0
148.7
(114.0)
58
Appendix 3. (continued)
DAY 5
STA
TAN
SPION
AMPH
CUM
OLIG
CAP
BIV
HARP
6
28.0
1.0
12.0
1L0
5.0
1.0
1.0
9.0
11.0
14.0
1.0
1141.0
26.0
33.0
51.0
31.0
59.0
35.0
75.0
57
10.0
1.0
1.0
5.0
8.0
9.0
15.0
16.0
7.0
142.0
148.0
51
139.0
101.0
113.0
166.0
81.0
113.0
14
16
29
39
69
77
87
142.0
36.0
25.0
20.0
140.0
3.0
6.0
leO
'16.0
6.0
5.0
7.0
314.7
1.9
(10.1)
(3.2)
118.0
68.0
73.0
111.3
(
31.7)
14.0
14.0
7.6
(5.2)
DAY
STA
TAN
SPION
2
68.0
111.0
97.0
58.0
98.0
96.0
113.0
108.0
53.0
78.0
114.0
27
141
53
63
72
73
83
811
96
88.0
(22.2)
8.8
1.L1
6.0
5.0
14.0
20.0
5.0
11.0
(".9)
3.0
2.0
1.0
0.0
3.0
2.0
4.0
614.0
148.0
514.0
0.0
109.0
1.7
56.5
(22.7)
(1.8) (1.3)
75
AMPH
CUM
OLIG
CAP
BIV
HARP
214.0
2.0
33.0
33.0
1.0
2.0
0.0
10.0
6.0
3.0
12.0
0.0
22.0
3.0
15.0
15.0
39.0
53.0
66.0
25.0
11.0
8.0
7.0
7.0
5.0
0.0
0.0
2.0
15.0
2.0
2.0
3.0
3.0
2.0
11.0
31.0
38.0
28.0
(
120
0.0
0.0
0.0
1.0
0.0
5.0
1.0
2.0
2.0
1.0
10.0
7.0
'12.0
0.0
2.0
37.0
26.0
9.0
5.0
30.6
8.1)
14.9
5.11
9.0
(14.1)
(14.2)
(6.9)
3.0
11.0
3.0
7.0
1.0
0.0
3.0
1.0
3.0
1.0
2.0
5.0
1.0
1.0
142.0
68.0
129.0
11414.0
39.0
157.0
3.5
1.9
76.2
(14.5)
(1.14)
(148.5)
59
Appendix 3. (continued)
DAY 10.5
STA
TAN
SPION
9
1514.0
10
103.0
60.0
16
22
30
33
52
78
85
98
OLIG
CAP
BIV
HARP
25.0
7.0
18.0
11.0
7.0
5.0
9.0
20.0
0.0
8.0
6.0
10.0
12.0
12.0
I.0
11.0
5.0
5.0
5.0
1.0
1.0
6.0
2.0
714.0
147.0
814.0
11.0
52.0
50.0
57.0
30.0
26.0
52.0
156.0
2.0
6.0
1.0
3.0
6.0
10.0
11.0
20.0
25.8
(6.2)
(5.6)
151.0
82.0
108.0
59.0
90.0
65.0
98.6
CUM
31.0
16.0
31.0
29.0
31.0
32.0
18.0
27.0
1114.0
(314.5)
AMPH
7.7
11.0
14.0
3.0
1.0
3.0
14,Q
1.0
6.8
7.8
(5.6)
14.7
2.14
(14.0)
(1.8)
62.8
(37.1)
CAP
BIV
HARP
1.0
37.0
31.0
(4.8)
SPION
AMPH
CUM
OLIG
7
1414.0
22.0
28.0
14.0
11.0
2.0
0.0
140.0
3.0
6.0
7.0
14.0
14.0
149
76.0
68.0
60.0
57.0
10.0
314
7.0
60
1114.0
714
78.0
58.0
69.0
87.0
6.0
22.0
1.0
76
79
86
111.0
19.0
29.0
314.0
36.0
22 0
71.1
(19.5)
C
26.7
8.2)
3.0
6.0
214.0
2.0
6.0
5.0
5.0
1.0
3.0
1.0
18.0
3.0
lt.0
11.0
14.7
(1.6)
(5.1)
2.0
3.0
0.0
13.5
TAN
23.0
2.0
0.0
3.0
10.0
5.0
STA
48
3.0
18.0
8.0
9.0
DAY
146
1.0
C
1.0
2.0
2.0
3.0
1.0
2.0
2.0
3.0
2.0
3.0
2.0
0.0
2.0
3.0
5.0
23.0
21 0
11.0
5.0
10.0
8.0
7.0
12.3
9.1)
3.2
(3.0)
3.8
(3.3)
141.0
36.0
214.0
39.0
141.0
1414.0
146.0
140.0
37.9
C
6.11)
60
Appendix 3. (continued)
DAY 19.5
STA
13
25
36
TAN
SPION
AMPH
CUM
OLIG
CAP
BIV
HARP
146.0
15.0
14.0
18.0
3.0
3.0
2.0
3.0
10.0
9.0
1.0
14.0
12.0
21.0
18.0
16.0
21.0
33.0
2.0
10.0
3.0
0.0
2.0
0.0
2.0
3.0
0.0
1.0
1.0
2.0
5.0
8.0
5.0
38.0
14.0
25.0
22.0
38.0
18.0
36.0
5.0
8.0
1.0
3.0
17.7
('6.6)
3.3
(2.2)
5.1
8.9
2.5
2.14
30.9
(2.8)
(14.8)
(2.4)
(2.5)
(11.8)
70
34.0
32.0
31.0
32.0
48.0
14.0
69.0
51.0
75
143.0
140
42
1414
147
56
40.0
(14.9)
4.0
2.0
2.0
I.Q
9.0
4.0
19.0
5.0
9.0
8.0
14.0
7.0
8.0
15.0
14.0
9.0
8.0
0.0
2.0
2.0
2.0
2.0
3.0
3.0
147.0
24.0
47.0
DAY 23.5
STA
TAN
SPION
AMPH
CUM
OLIG
CAP
BIV
HARP
6.0
9.0
2.0
14.0
1.0
1.0
1.0
4.0
2.0
8.0
14.0
11.0
1.0
3.0
15.0
6.0
3.0
51.0
27.0
35.0
72.0
36.0
53.0
17.0
6.0
82.0
31.0
119.0
18.0
1.0
1.0
18
143.0
114.0
20
39.0
21
147.0
23
36.0
43
141.0
15
58
17.0
27.0
58.0
12.0
13.0
14.0
19.0
17.0
9.0
15.0
3.0
3.0
82
146.0
29.0
3.0
5.0
9.0
1.0
5.0
3.0
3.0
1.0
8.0
11.0
5.0
3.0
5.0
3.6
(2.3)
(3.1)
1
50
140.3
(11.6)
16.0
(
5.11)
14.0
14.0
3.0
14.5
I.0
7.0
6.6
(3.5)
14.0
1.0
14.0
14.0
1.0
7.0
1.0
3.0
2.0
3.0
2.0
2.14
2.7
141.0
(1.3)
(1.9)
(23.7)
61
Appendix 14.
Raw faunal counts from pit treatment cores.
Means
and standard deviations for each taxon are given.
missing data.
DAY 0
STA
TAN
SPION
AMPH
1.0
1,0
CUM
OLIG
CAP
0.0
0.0
0.0
****
****
66
68
71
114.0
93
94
99
31.0
0.0
7.0
1.0
0.0
1.0
****
****
****
****
****
****
3.11
1.9
03
19
10
14
11
61
0.0
181
(11.3)
3.0
6.0
6.0
0.0
14.0
14.0
(2.7)
3.0
0.0
10.0
1.0
0.0
(3.2)
0.0
0.0
0.0
1.0
0.0
1.0
0.0
1.0
0.0
0.0
0.0
3.0
3.0
3.0
1.0
5.0
0.0
2.0
(0.7)
(1.7)
HARP
0.0
0.0
0.0
1.0
0.0
0.0
0.0
0.0
3.0
1.0
0.0
1.0
1.0
1.0
1.0
0.0
13.0
23.0
11.0
35.0
10.0
26.0
3
BIV
14.0
14.0
3.0
3.0
0.0
0.0
0.0
14.0
16
014
(1.2)
(1.0)
CAP
BIV
(1.9)
DAY 1
STA
8
32
38
511
55
59
65
80
88
97
TAN
162.0
95.0
77.0
90.0
87.0
89.0
111.0
611.0
71.0
56.0
90.2
(29.9)
SPION
AMPH
13.0
11.0
5.0
5.0
5.0
20.0
37.0
36.0
20.0
36.0
28.0
39.0
11.0
25.1
(11.14)
8.0
1.0
0.0
3.0
3.0
3.0
1.0
3.I
(2.14)
CUM
OLIG
1.0
1.0
0.0
2.0
2.0
1.0
1.0
0.0
0.0
3.0
13.0
8.0
6.0
9.0
7.0
12.0
5.0
7.0
1.0
7.0
0.0
2.0
13.0
8.0
12.0
8.0
5.0
14.0
4.0
1.0
1.0
0.0
7.6
(3.0)
6.0
(14.14)
0.9
(0.7)
(1.9)
5.0
HARP
107.0
49.0
1.0
1.0
0.0
I8.0
123.0
120.0
122.0
153.0
99.0
136.0
216.0
3.0
1.0
0.0
6.0
1.6
117.3
(
148.7)
62
Appendix '1. (continued)
DAY 2
STA
TAN
SPION
AMPH
CUM
OLIG
CAP
BIV
HARP
31.0
36.0
16.0
30.0
30.0
20.0
26.0
0.0
5.0
11.0
2.0
19.0
7.0
13.0
6.0
2.0
0.0
113.0
107.0
79.0
88.0
86.0
1.0
16.0
7.0
7.0
2.0
1.0
7.0
2.0
3.0
3.0
2.0
1.0
2.0
6.0
178.0
127.0
75.0
106.0
46.0
195.0
90.0
156.0
88.0
73.0
5
12
15
17
24
37
62
67
81
92
113.14
(
49.1)
(
8.0
5.0
3.0
211.0
36.0
7.0
8.0
39.0
39.0
33.0
6.0
111.0
0.0
12.0
2.0
30.0
5.4
(7.0)
12.3
7.6)
3.0
1.0
14Q
(
9.6)
11.0
3.0
3.0
0.0
1.0
1.0
0.0
****
1.0
5.0
1119.0
'16.0
1011.0
1.0
115.0
91.0
5.2
1.11
(14,3)
(1.7)
2.8
(2.1)
97.8
(27.1)
DAY 3
STA
TAN
SF1 ON
AMPH
CUM
OLIG
CAP
BIV
HARP
25.0
26.0
21.0
28.0
1.0
8.0
3.0
11,0
5.0
2.0
6.0
6.0
8.0
7.0
17.0
1.0
6.0
16.0
2.0
0.0
2.0
0.0
3.0
3.0
1.0
0.0
1.0
5.0
3.0
1.0
1.0
8.0
3.0
1113.0
75.0
161.0
172.0
217.0
128.0
79.0
19
28
31
35
611
89
90
211.0
26.0
26.0
16.0
611.0
611.0
511.0
91
95
100
28.0
83.0
111.0
109.7
(
56.3)
26.1
(
6.3)
3.0
6.0
9.0
6.0
10.0
6.0
9.0
7.0
37.0
32.0
58.0
16.0
59.0
6.2
23.8
3.0
12.0
11.0
(3.5) (21 .'l)
7.4
(5.3)
74.0
1143.0
117.0
118.0
2.0
1214.0
5.0
0.0
0.0
2.0
1.7
2.5
(1.6) (2.5)
119.0
69.0
59.0
80.0
1011.6
(
31.2)
63
Appendix 11. (continued)
DAY 5
STA
TAN
6
iLl
26
29
39
51
57
69
77
87
SF ION
AMPH
CUM
19.0
13.0
8.0
15.0
8.0
3.0
10.0
11.0
11.0
11.0
198.0
81.0
39.0
78.0
114.0
211.0
50.0
201.0
80.0
88.0
35.0
27.0
34.0
23.0
38.0
8.0
96.14
20.9
(10.3)
(59.11)
2.0
1.0
11.0
5.0
14.0
8.0
1.0
11.0
(2.5)
3.0
7.0
6.0
5.0
22.0
26.0
6.0
9.3
(8.0)
OLIG
CAP
0.0
0.0
3.0
0.0
0.0
2.0
14.0
1.0
3.0
2.0
10.0
5.0
6.0
5.0
17.0
6.3
(5.7)
BIV
HARP
1.0
105.0
87.0
38.0
56.0
5.0
0.0
11.0
1.0
1.0
1.0
9.0
5.0
16.0
0.0
80.0
113.0
86.0
88.0
145.0
2.2
(2.0)
3.9
(5.2)
(32.6)
11.0
1.0
2.0
6.0
414.0
8'4.2
DAY 7.5
STA
TAN
2
1511.0
27
106.0
106.0
209.0
116.0
165.0
150.0
86.0
136.0
83.0
41
53
63
72
73
83
811
96
131.1
(
39.11)
SF1 ON
AMPH
CUM
OLIG
CAP
BIV
HARP
23.0
25.0
21.0
4.O
9.0
3.0
1.0
5.0
146.0
5.0
3.0
3.0
2.0
3.0
3.0
0.0
23.0
12.0
2.0
0.0
3.0
7.0
1.0
2.0
1.0
3.0
0.0
0.0
60.0
3.0
3.0
1.0
10.0
3.0
5.0
11.0
2.0
14.0
18.0
12.0
3.0
8.0
1.0
0.0
2.0
1.0
33.0
79.0
162.0
72.0
124.0
102.0
3.7
7.9
9.7
1.9
2.7
(2.4)
(141.3)
34.0
38.0
13.0
23.0
36.0
30.0
28.9
(
9.7)
9.0
2.0
(2.1)
(5.9)
14.0
10.0
11.0
19.0
13.0
3.0
(7.3) (2.1)
3.0
115.0
311.0
611.0
77.5
64
Appendix 11. (continued)
DAY 10.5
STA
TAN
SPION
t.0
11.0
6.0
30.0
22.0
16.0
19.0
3.0
2.0
1.0
0.0
2.0
13.0
11.0
10.0
6.0
10.0
7.0
7.0
12.0
13.0
13.0
11.9
8.0
6.7
78
711.0
85
98.0
65.0
35.0
32.0
22.0
26.0
1111.0
211.2
(32.2)
(
OLIG
15.0
52
98
CIJM
25.0
136.0
117.0
108.0
97.0
136.0
139.0
170.0
9
10
16
22
30
33
AMPH
6.7)
(3.5)
11.0
7.0
5.0
6.0
8.0
7.0
3.0
13.0
2.0
11.0
11.0
2.0
(3.3)
(14.9)
CAP
1.0
11.0
13.0
0.0
1.0
2.0
0.0
2.0
1.0
2.0
BIY
HARP
7.0
1.0
7.0
139.0
115.0
89.0
71.0
6.0
2.0
1140.0
3.0
71.0
150.0
61.0
212.0
2.0
5.0
1.0
2.0
2.6
(3.8)
(2.11)
CAP
BIV
2511.0
3.6
(
123.2
69.0)
DAY 13.5
STA
TAN
SPION
7
155.0
3)4
1115.0
'16
79
75.0
128.0
87.0
120.0
126.0
50.0
93.0
86
60. 0
25.0
27.0
29.0
35.0
36.0
28.0
29.0
31.0
23.0
22 0
103.9
28.5
118
I9
60
711
76
(
36.1)
(
11.6)
AMPH
3.0
3.0
5.0
2.0
8.0
11.0
CUM
1.0
1.0
14.0
19.0
11.0
'5.0
OLIG
8.0
1.0
9.0
10.0
11.0
23.0
1.0
5.0
11.0
11.0
8.0
5.0
11.0
'2.0
3.0
3.0
18.0
3.0
5.0
1.0
30.0
10.0
11.0
100
2.0
2.0
514
(11.7)
9.6
9.2
11.3
(9.11)
(6.)4)
111.0
2.0
(3.0)
9.0
5.0
11.0
7.0
0.0
1.0
1.0
15.0
3.0
5.0
5.0
(14.5)
HARP
65.0
117.0
55.0
95.0
33.0
102.0
56.0
52.0
71.0
83.0
65.9
(21.9)
65
Appendix
4
(continued)
DAY 19.5
STA
TAN
SF ION
140
614.0
147.0
145.0
23.0
13.0
9.0
8.0
142
41.0
114.0
1411
141.0
16.0
25.0
12.0
23.0
13
25
36
147
56
70
75
70.0
70.0
109.0
52.0
60.0
59.9
(20.5)
31 .0
17.14
(
7.6)
AMPH
3.0
0.0
0.0
2.0
3.0
14.0
6.0
2.0
5.0
7.0
3.2
(2.3)
CUM
OLIG
7.0
6.0
9.0
3.0
12.0
5.0
38.0
8.0
2.0
10.0
12.0
5.0
14.0
14.0
5.0
1.0
10.0
11.0
13.0
14.0
6.5
10.14
(14.0)
(10.2)
CAP
Bill
3.0
0.0
1.0
2.0
11.0
1.0
1.0
10.0
3.0
14.0
0.0
5.0
3.0
5.0
3.0
2.0
8.0
3.0
0.0
3.3
(3.0)
(3.14)
14.0
3.6
HARP
17.0
38.0
33.0
26.0
42.0
18.0
141.0
145.0
314.0
147.0
314.1
(10.7)
DAY 23.5
STA
TAN
SF1 ON
AMP}I
50
145.0
114.0
58
66.0
17.0
82
114.0
224.0
0.0
7.0
3.0
2.0
0.0
9.0
1.0
3.0
1.0
10.0
16.0
6.8)
3.6
(3.7)
1
18
20
21
86.0
15.0
9.0
11.0
611.0
211.0
142.0
124.0
245
34.0
33.0
6.0
23.0
27.0
23
143
17.0
145.7
(21.3)
(
CUM
3.0
2.0
6.0
2.0
14.0
13.0
114.0
2.0
0.0
13.0
OLIG
7.0
11.0
5.0
8.0
2.0
8.0
8.0
22.0
9.0
13.0
5.9
9.3
(5.14)
(5.14)
CAP
0.0
8.0
2.0
14.0
2.0
5.0
3.0
5.0
2.0
5.0
3.6
(2.3)
BIll
3.0
3.0
2.0
2.0
2.0
5.0
6.0
HARP
147.0
35.0
36.0
1414.0
1411.0
514.0
143.0
3.0
20.0
52.0
31.0
3.9
(2.8)
(10.3)
11.0
2.0
140.6
66
Appendix 5.
Raw faunal counts from defaunated treatments.
Means
and standard deviations for each taxon are given.
= missing data.
DAY 0
BIV
HARP
0.0
0.0
****
0.0
0.0
****
0.0
****
0.0
0.0
0.0
****
****
****
****
0.0
0.0
0.0
****
****
****
****
0.0
0.0
0.0
****
****
****
****
00
00
00
00
10
(0.0)
(0.0)
(0.0)
(0.0)
(1.0)
BI'!
HARP
STA
TAN
SF1 ON
AMPH
CUM
OLIG
CAP
3
0.0
0.0
****
0.0
0.0
****
0.0
0.0
****
0.0
0.0
****
0.0
0.0
****
91;
0.0
2.0
2.0
****
****
****
22.
____
0.0
0.0
1.0
****
****
****
****
0.0
0.0
0.0
****
****
****
****
0.0
0.0
0.0
****
****
****
****
08
02
00
(1.1)
(0.1;)
(0.0)
1;
11
61
66
68
71
93
1.0
2.0
0.0
2.0
****
****
****
DAY 1
STA
TAN
SF1 ON
AMPH
CUM
aLl G
CAP
8
32
38
****
****
****
****
****
****
33.0
9.0
****
7.0
2.0
****
****
12.0
2.0
****
****
0.0
0.0
****
0.0
1.0
****
0.0
0.0
211.0
1.0
55
59
65
80
88
6.0
****
2.0
****
0.0
****
11.0
****
0.0
****
****
1.0
****
0.0
****
0.0
****
21.0
****
30.0
****
711.0
3.0
****
****
****
5.0
****
****
****
****
****
****
71.0
****
****
____
0.0
****
****
****
0.0
****
****
2!.
11.0
****
****
****
7.6
(6.7)
0.0
5.6
(0.0)
(14.1)
1.7
(2.0)
2.1
(1.6)
51;
****
****
36.'
(25.0)
11.0
0.3
(0.8)
52.6
(32.7)
67
Appendix 5. (continued).
DAY 2
BIV
HARP
2.0
****
****
0.0
****
****
29.0
****
13.0
3.0
2.0
2.0
1.0
****
****
2.0
79.0
28.0
13.0
33.0
kO.0
STA
TAN
SF1 ON
AMPH
CUM
OLIG
CAP
5
6.0
****
****
1LLO
2.0
3.0
****
****
ILO
****
****
1.0
****
****
2.0
1.0
32.0
7.0
****
****
11.0
0.0
0.0
12.0
0.0
****
****
.2.
____
2.0
0.0
1.0
2.0
1.0
****
****
21.0
81
30.0
****
****
3k.0
20.0
2k.O
29.0
53.0
****
1.5
11.2
12
15
17
2k
37
62
67
4.O
16.0
10.0
****
****
31.7
8.7
(11.5)
(5.6)
(1.0) (12.5)
0.0
0.0
1.0
1.0
****
k.0
3.8
0.7
(5.8)
(k.5)
(0.8)
37.0
(22.k)
DAY 3
CAP
BIV
HARP
1.0
6.0
3.0
2.0
1.0
1.0
0.0
****
****
****
****
3.0
8.0
****
****
****
****
2.0
0.0
1.0
0.0
2.0
****
****
****
****
23.0
37.0
29.0
22.0
15.0
3.0
7.0
2.0
29.0
1.5
k.8
(2.5)
1.2
(1.0)
STA
TAN
SF1 ON
AMPH
CUM
OLIG
19
28
2k.0
70.0
k5.0
33.0
11.0
13.0
5.0
7.0
7.0
****
****
****
****
ik.0
2.0
2.0
3.0
0.0
1.0
****
****
****
****
11.0
10.0
3.0
3.0
5.0
****
****
****
****
2.0
26.0
9.5
(3.7)
1.7
(1.0)
31
35
6k
89
90
95
kl.0
****
****
****
****
100
29.0
91
kO.3
(1 6.k)
9.7
(8.7)
(1.2)
3.0
25.8
(
7.5)
Appendix 5. (continued)
DAY 5
SPION
OLIG
CAP
BIV
HARP
STA
TAN
6
118.0
****
****
****
****
****
73.0
****
****
0.0
1$
117.0
18.0
17.0
7.0
11.0
1.0
6.0
1.0
0.0
1.0
1.0
0.0
3.0
3.0
11.0
1.0
1.0
11.0
10.0
12.0
3.0
0.0
1.0
0.0
2.0
1.0
5.0
26
29
39
51
57
69
77
7.0
92.0
30.0
56.0
33.0
85.0
111.0
12.0
****
****
55.9
(211.1)
(
AMPH
0.0
0.0
6.0
0,0
****
****
****
****
****
****
****
****
****
0.0
28.0
26.0
26.0
105.0
33.0
55.0
0.6
6.6
(0.5)
2.6
(1.9)
5.6
(11.1)
(14.1)
0.9
(1.2)
(30.3)
****
****
****
****
12.3
11.1!)
CUM
6.0
10.0
10.0
11.0
2.0
5.0
3.-0
****
****
149.11
DAY 7.5
STA
TAN
SPION
AMPH
CUM
OLIG
CAP
2
186.0
62.0
95.0
105.0
15.0
16.0
19.0
26.0
38.0
7.0
2.0
2.0
8.0
5.0
3.0
2.0
11.0
0.0
2.0
6.0
11.0
0.0
9.0
12.0
8.0
****
****
27
111
53
63
72
73
83
1511.0
2.0
11.0
9.0
0.0
BIV
1.0
0.0
3.0
2.0
3.0
1.0
0.0
1.0
30.0
1.0
12.0
9.0
****
****
****
****
HARP
56.0
26.0
92.0
214.0
113.0
****
****
3.0
811
****
****
****
****
11.0
11.0
96
39.0
15.0
3.0
9.0
5.0
6.0
1.0
96.14
23.3
(11.0)
14.1
6.6
('4.5)
6.9
6.1
1.11
71.9
(9.7)
(11.5)
(1.2)
(142.1)
77.0
53.0
(50.9)
142.0
15.0
(2.3)
****
****
1141.0
80.0
****
****
143.0
Appendix 5. (continued)
DAY 10.5
STA
TAN
SPION
AMPH
CUM
OLIG
CAP
9
148.0
114.0
2,0
9.0
23.0
56.0
62.0
1.0
8.0
8.0
11.0
2.0
2.0
1.0
10.0
2.0
0.0
1.0
2.0
12.0
23.0
16.0
21.0
114.0
2.0
8.0
7.0
14.0
6.0
1.0
10
16
22
30
33
52
78
85
98
614.0
81.0
79.0
****
****
9.0
1.0
21.0
****
****
2.0
****
****
314.0
17.0
0.0
16.6
1.4
(0.7)
55.9
(20.3)
(
14.9)
8.0
6.0
2.0
6.0
14.0
14.0
6.0
14.0
****
****
0.0
****
****
9.0
****
****
18.0
6.0
6.0
BIV
0.0
3.0
****
****
0.0
HARP
13.0
93.0
109.0
95.0
28.0
145.0
25.0
****
****
70.0
8.14
3.14
7.9
2.3
59.8
(14.6)
(3.1)
(3.14)
(2.1)
(36.8)
DAY 13.5
CAP
BIV
HARP
8.0
8.0
5.0
****
2.0
3.0
****
32.0
9.0
****
114.0
27.0
****
****
****
****
11.0
13.0
5.0
****
****
****
****
11.0
7.0
****
****
****
****
11.0
11.0
1.0
****
****
****
****
2.0
****
****
****
****
55.0
51.0
57.0
****
****
****
****
211.0
14.6
5.0
12.14
8.14
5.0
117.14
(10.0)
(2.9)
(5.5)
(3.6)
(3.9)
(10.4)
STA
TAN
SPION
AMPH
CUPI
7
149.0
148.0
146
****
17.0
16.0
****
5.0
0.0
****
1.0
314
1.0
****
93.0
68.0
88.0
****
****
****
****
35.0
7.0
17.0
14.0
35.0
****
****
****
****
69.2
(21.1)
148
149
60
714
76
79
OLIG
14.0
(
8.9)
7.0
142.0
****
70
Appendix 5. (continued)
DAY 19.5
STA
TAN
SPION
AMPH
CUM
13
34.0
32.0
2.0
1.0
6.0
36
111.0
1.0
40
114.0
112
25.0
1111
111.0
117
****
16.0
10.0
12.0
10.0
16.0
16.0
****
0.0
25
0.0
****
0.0
7.0
5.0
5.0
****
36.0
39.0
****
11.0
12.0
****
5.0
2.0
2.0
****
****
1.9
(1.8)
(2.11)
56
70
75
36.5
(
6.1)
12.9
( 2.7)
11.0
2.0
OLIG
11.0
3.9
CAP
5.0
2.0
0.0
8.0
3.0
10.0
31.0
6.0
11.0
****
6.0
8.0
****
20.0
6.0
****
0.0
8.0
****
11.9
'1.8
9.0
(9.2) (3.7)
BIV
5.0
0.0
0.0
0.0
3.0
HARP
13.0
16.0
32.0
20.0
1.0
****
68.0
28.0
****
11.0
113.0
3.0
****
23.0
****
2.0
30.11
(2.0)
(17.9)
DAY 23.5
STA
1
18
TAN
SPION
AMPH
CUM
119.0
15.0
13.0
18.0
9.0
2.0
5.0
6.0
0.0
2.0
9.0
5.0
3.0
5.0
5.0
9.0
17.0
11.0
21
23.0
35.0
39.0
23
117.0
113
35.0
18.0
****
20
45
50
58
82
11.0
****
32.0
****
11,0
****
311.8
(10.7)
12.0
(
14.7)
6.0
OLIG
****
6.0
3.0
17.0
8.0
****
7.0
7.0
6.0
****
5.0
****
2.0
****
****
3.8
(1.9)
(14.9)
11.0
11.0
6.1
11.0
CAP
0.0
7.0
2.0
BIV
3.0
5.0
HARP
118.0
11.0
0.0
0.0
7.0
****
3.0
0.0
7.0
****
66.0
61.0
52.0
67.0
59.0
22.0
****
5.0
****
0.0
****
25.0
****
3.1
(3.0)
(17.6)
11.0
5.8
3.6
(1.9) (2.8)
7.0
50.0
71
Appendix 6.
Concentration of chlorophyll a in ug pigment per
gram of sediment in sediment core sections.
Means and standard
= missing data.
deviations are given after each date.
DAY 0
CONTROL
STA
3
'4
61
66
68
01
12
203
26.17
25.88
15.86
12.81
9.114
214.149
12.82
9.97
****
9.85
8.02
9.07
9.25
7.95
8.27
****
****
71
17.12
25.62
93
114.311
911
****
99
15.511
12.56
****
12.09
8.37
16.62
9.99
9.30
8.72
10.87
7.68
11.70
9.07
9.18
10.61
3r11
311
12
On
****
****
****
****
****
****
****
****
lt-2
0-1
35.03
****
****
****
****
****
29.51
33.81
****
2r3
**
****
****
****
****
9.91
7.52
8.61
****
****
20.78 13 11
10 52
8 76
( 5.67)(5.20)(i.714)( 0.82)
DAY 1
PIT
CONTROL
STA
8
32
38
0-1
1-2
2-3
31l
3-k
2-3
19.86
17.20
25.13
11.83
10.22
10.19
8.30
10.03
111.79
22.12
20.71
11.116
7.814
11.23
11.08
8.10
10.25
16.113
13.111
10.214
8.9'4
5.21
17.76
11.38
11.68
10.11
17.21
15.611
7.19
9.95
8.99
8.55
11.88
17.98
25.08
23.55
30.87
10.60
55
214.27
10.118
59
21.28
65
80
88
111.91
514
97
19.82
22.12
21.22
12.115
19.12
13.36
3.113
19.63 13.19 11.02
8.911
( 1l.141)(11.73)(2.66)( 1.11)
I
(
'40.77
11.614
32.85
26.89
28.20
18.77
15.11
23.814
20.23 27.18
9.81)( 5.71)
''''
****
''''
****
****
****
****
****
72
Appendix 6. (continued)
DAY2
CONTROL
0-1
STA
1-2
18.59 11.78
15.55
9.00
18.68
9.34
13.75
7.86
5
12
15
17
2-3
8.87
8.77
5.22
9.02
10.95
214
8.148
114.57
37
214.65
18.19
****
62
67
19.714
11.143
12.114
9.25
11.59
'6.81
9.56
21.87
81
15.142
92
22.96
7.33
18.314
17.97 12.00
(
14.82)( 3 95)(
3-lI
3_14
12.28 18.78
7.68 12.63
12.6'4 21.18
8.38 11.214
12.143 23.92
114.95 19.98
15.06 25.36
8.23 23.09
16.23 23.26
11.65 23.67
6.69
8.011
5.37
8.614
7.88
9.00
9.73
8.88
6.93
5.93
11.95
8.89
7.71
1
93)( 1 43)
DAY
2-3
(
1-2
0-1
****
''''
****
13.143
26.15
23.26
23.35
****
****
30.00
****
38.90
****
****
****
****
*1
****
25.85
84)( 8 142)
20.31
3 03)(
14
3
CONTROL
STA
19
28
31
35
614
89
90
91
95
01
lr.2
2-3
3-14
3r14
2r3
1r2
On
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
17.16 23.00
25.00 22.63
16.36 26.141
11.58 10.29
13.12 11.59 8.51
18.86 23.17 11.147
9.98
15.26 15.80 114.01
9.27
20.12 11,19
8.68
9.70
16.51 11.51
8.42
9.46
21.39 16.66 114.37 11.20
18.814
15.142
22.81
!22.
19.11
15.27
****
****
11.711
9.148
C 2.63)('4.08)(1.90)( 1.05)
25.149
17.214
214.55
19.81
23.141
21.91
****
22.79 23.86 214.33
11.07 20.00 20.68
****
C
****
****
****
20.67 23.38 23.22
'4.22)( 2.20)( 1.22)
****
73
Appendix 6. (continued)
DAY 5
PIT
CONTROL
0-1
STA
6
111
26
29
39
51
57
69
77
87
16.86
20.38
21.18
20.77
11.25
15.18
21.96
17.65
1-2
2-3
13.814
11.55
9.53
15.314
****
10.55
9.23
12.58
2r3
1-2
****
****
****
****
11.014
7.13
6.99
8.79
14.90 21.05 26.13
11.59 17.15 18.1414
114.145 19.55
****
15.814 15.20
11.00
19.33 18.714
10.62 20.12 22.58
114.36 18.01 22.49
20.38 29.78
10.30
9.32
114.72
9.147
9.08
12.314
11.214
10.514
12.33
8.65
7.86
****
9.96
18.1414
18.15
12.55
( 3.66)(3.08)(
3-14
12.56
8.55
9.06
10.86
8.13
13.148
3-14
''''
10.71
1.143)( 2.014)
(
DAY
7.5
19.95
PIT
23
34
17.73
19.51 19.55
16.28 11.38
19.114 16.47
19.38 12.63
18.53 114.143
114.55
12.20
13.20
13.32
8.72
11.12
13.03
16.27 10.28
19.98 10.514
9147
12.15
10.45
12.20
11.17
8.05
9.10
9.55
6.96
8.93
8.214
****
****
0-1
2
27
22.60
141
53
63
72
73
83
814
2.
____
****
1I.13 11.62 9.76
2.05)( 3.149)( 2.15)( 1.86)
18.96
(
1r2
22.141
3.145)( 1L37)( 3.114)
CONTROL
STA
0-1
3r14
****
15.77
10.70
17.26
15.01
17.93
17.46
10.87
'''
****
23
12
23.714
21.96 214.214
18.62 25.00
23.17
22.53 25.143
23.32 214.145
20.28
17.92 214.35
19.13
****
15.00 21.67 214.69
(3.85)( 1.89)( 0.50)
0-1
74
Appendix 6. (continued)
DAY
10.5
PIT
CONTROL
STA
9
10
16
22
30
33
0-1
1-2
18.26
9.67
19.514 11.52
17.62 12.23
21.85 10.45
18.15 14.82
2-3
3-4
9.54
9.47
9.25
8.29
7.07
9.35
9.147
10.414
12.16
9.02
6.77
8.78
8.08
18.31
12.614
78
19.12
17.08
15.11
10.61
12.54
9.67
16.28
8.99
85
98
18.35
12.68
9.38
18.70
12.19
52
**
(1.39)(.i.88)(
***
DAY
0-1
214.28
****
****
19.50
10.64
11.34
19.69
19.05
****
2-3
21.57
13.15
8.64
8.24
13.13
10.67
19.02
8.1414
13.33
13.13
7.36
11.06
8.88
10.51
2.)41)( 1.66)
1-2
3_14
12.13
**
12.143
15.18
18.01
17.22
26.95
****
16.02
19.67
15.18
(14.78)( 4.73)(
PIT
3_14
12.56
8.89
8.11
****
****
****
****
15.50
15.70
17.55
19.82
19.86
12.88
16.90
18.14
10.02
6.37
13.35
13.66
11.89
9.34
11.04
8.86
5.99
9.05
13.714
8.86
13.04 12.58
10.57
9.53
7.15
9.75
10.72
7.71
9.11 10.40
11.11
21.92
17.146
11.21
1*,2
20.81
314
****
46
48
49
7
60
74
76
79
86
(2.53)(
12.614
3-14
8.82
2.33)( 1.88)( 1.93)
2f-3
I
I
1-2
On
15.00 20.59
31.39
****
****
****
****
17.36
21.53
10.87 19.68
9.k5 10.86
8.27 12.145
8.64 13.47
5.88 13.60
8.111
12.85
****
10.59
14.141)
13.5
2-3
Or1
****
20.88
20.61
CONTROL
STA
21.149
13.32
11.03
31.57
29.82
17.43 25.71
****
18.70
19.70 23.11
22.07 25.09
20.02 21.82
''''
11.06 15.82 24.02 23.93
(14.79)( )4.00)( 5.67)( 1.79)
75
Appendix
6.
(continued)
DAY 19.5
CONTROL
STA
0-1
13
25
36
70
21.54
15.69
15.56
17.06
20.12
19.17
16.12
75
15.119
110
142
1411
117
56
1-2
2-3
3_14
17.66
9.145
7.83
5.72
14.O1t
8.15
13.32
10.06
6.91
11.79
9.611
11.26
9.146
8.146
12.10
7.60
314
2-3
1-2
0-1
13.83
5.62
13.214
10.10
17.90
15.33
16.914
214.16
11.71
19.29
9.12
10.03
6.10
16.45
8.53
8.36
16.98
11.18
18.149
****
11.01
8.011
9.81
9.37
****
8.55
****
7.98
****
6.9'4
7.1414
****
****
214.35
12.16
12.91
10.15
12.86
8.22
11.28
16.77
17.33
13.111
18.21
19.38
22.31
12.30
8.145
6.911
6.1411
8.01
13.141
*''
****
17.38
9.89 11.16 15.96 18.76
( 3.69)(k.76)( 14.87)( 2.98)
17.25 10.611
8.45
9.33
2.37)( 1.89)( 1.85)( 2.71)
I
DAY
23.5
PIT
CONTROL
O-1
1-2
2e3
18.88
13.114
10.83
11.12
10.90
10.02
10.142
21
1)4.66
21.142
18.119
23
15.99
10.31
113
114.86
9.141
****
17.30
8.148
58
21 .67
82
2)4.2)4
17.25
17.23
STA
1
18
20
115
50
18.61
9.63
3-14
2-3
1-2
0-1
9.37
11.91
16.61
8.19
8.314
7.31
7.81
7.61
23.38
21.42
16.65
8.110
7.80
18.37
9.76
10.20
7.79
8.88
10.17
6.95
9.75
9.5)4
111.07
12.67
3_14
7.92
6.63
8.19
9.36
9.69
11.75
9.95
8.39
( 3.30)( 3.15)( 2.2J4)( 1.03)
9.11
7.11
6.90
7.2)4
6.914
9.51
7.93
8.19
6.83
9.00
11.18
10.91
12.51
20.02
11.99
111.211
15.146
11.142
19.81
10.72
11.83
21.15
16.35
15.611
25.21
16.27
25.70
19.73
9.28 11.18 12.414 20.'49
( 2.32)( 14.36)( 3.50)( 3.61)
76
Appendix 7:
Percent weight loss on ignition of sediment core
Means and standard deviations are given for each
sections.
section.
missing data.
97a and 97b denote a pair of
ambiguously numbered cores.
DAY 0
PIT
CONTROL
STA
0-1
1-2
2-3
3-4
3-4
2-3
1-2
3
2.3k
**
****
1.48
1.60
****
61
**
****
****
****
****
****
****
****
****
****
****
****
4
1.69
1.99
****
****
****
11
1.95
2.55
****
****
****
****
****
****
****
66
****
69
2.08
2.85
1.92
1.87
1.87
71
93
94
99
1.33
1.50
1.98
1.51
1.60
1.10
2,16
1.69
(0.38) (0.45)
1.42
1.17
1.59
1.60
1.32
1.63
1.11
1.27
1.57
1.21
1.31
1.05
1.26
1.47
1.39
(0.18)
(0.31)
0-1
DAY 1
PIT
CONTROL
STA
8
32
38
54
55
59
80
88
97a
97b
01
1-2
2r3
3-k
34
2P3
1-2
2.25
2.63
2,17
2.19
1.68
2.17
2.10
2.28
1.50
1.63
1.82
1.18
1.22
1.55
1.33
1.36
1.7k
1.0k
1.73
1.95
2.17
1.28
1.09
1.36
1.65
2.16
2.09
1.85
2.08
1.53
2.75
3.03
3.53
3.73
2.50
****
****
****
****
****
****
1.73
****
****
1.140
0.91
2.21
2.41
1.33
2.60
1.99
2.15
2.39
1.31
1.1k
1.25
1.36
1.09
1.73
1.80
1.50
2.20
1.78
1.53
1.36
(0.214) (0.52) (0.36) (0.25)
3.01
1.81
Oh 1
****
1.85
1.98
I
I
2.70
2.62
1.97
(0.146) (0.75)
** **
77
Appendix
(continued)
7.
DAY 2
PIT
CONTROL
01
01
i2
2r3
3f-k
3rk
2r3
1r2
2.19
1.88
2.72
1.82
2.20
1.73
1.32
i.tO
1.13
0.93
2.03
1.50
2.35
2.16
2.k6
**
1.51
2.kl
1.29
1.21
1.26
1.70
1.16
2.00
1.12
1.k9
****
i.1t2
1.k7
1.1k
1.06
1.23
2.115
1.811
1.117
1.81
62
67
2.110
1.35
1.29
81
2.08
2.53
1.90
1.82
1.09
2.82
1.78
1.32
2.59
****
****
****
STA
5
12
15
17
2k
37
92
2.91
1.31
2.32
1.65
(0.35) (0.50)
1.11
0.93
1.30
1.011
2.33
1.23
1.82
1.02
1.80
2.77
2.35
2.83
2.39
2.38
2.83
1.29
1.20
(0.18)
1.65
(0.39)
2.29
2.84
(0.149)
(0.75)
1.1411
(0.211)
****
3.22
****
11.18
**'*
DAY3
PIT
CONTROL
STA
Or-i
1-2
2r3
3r-14
3r-11
2-3
1,2
Or-i
19
****
****
****
****
****
****
****
****
28
****
****
****
****
****
****
****
31
2.3k
2.35
2.1k
1.92
**'
2.111
1.81
2.58
2.02
2.39
2.03
1.68
2.10
****
1.73
1.53
2.20
****
2.19
2.63
1.98
2.80
2.22
2.55
2.1411
1.711
1.66
1.29
1.56
1.27
1.36
2.95
2.1111
1.87
1.7k
1.58
****
****
35
6k
89
90
91
95
1.22
2.22
1.71
2.00
1.81
1.71
****
1.78
1.52
(0.28) (0.26) (0.22) (0.22)
1.117
****
2.26
(0.115)
2.83
2.53
2.113
2.51
****
2.511
*'
2.55
1.96
****
2.29
2.77
****
****
****
****
2.511
2.50
(0.32) (0.20)
78
Appendix 7. (continued)
DAY 5
PIT
CONTROL
STA
6
14
26
29
39
Ot1
2.33
2.09
2.19
1.94
i-2
2-3
3-4
3-4
2-3
1.82
1.28
1.07
1.27
1.13
1.63
1.53
1.07
1.45
1.38
1.27
1.23
1.54
2.33
2.03
2.38
1.88
1.59
1.88
3.20
2.20
2.30
1.72
2.39
1.30
1.67
1.76
57
69
77
2.86
1.73
2.36
2.72
1.92
1.31
1.31
1.41
87
1.97
2.11
51
1.45
1.27
2.21
1.54
(0.36) (0.28)
1.51
1.59
1.16
1.22
1.32
1.40
1.23
1.58
1.34
1.35
(0.18) (0.19)
1.71
1.12
1.50
1.62
1.60
2.43
1.83
1.84
2.37
1.87
(0.38)
1'-2
2.16
O'-i
2.65
1.99
2.37
2.75
2.56
2.51
2.38
****
2.46
(0.46) (0.25)
DAY 7.5
PIT
CONTROL
O-1
1-2
23
3J4
3.44
2-3
1r2
On
2
27
2.46
1.75
1.87
1.77
****
2.03
1.51
2.11
1.98
2.58
1.69
1.57
2.07
2.79
53
67
72
73
83
84
****
1.99
2.48
2.17
2.86
1.51
****
****
2.15
2.29
2.43
2.36
2.17
****
1.88
****
.2.
____
2.06
1.64
1.19
1.67
1.37
1.25
1.54
1.35
1.35
****
2.54
****
141
2.06
1.73
1.25
1.92
1.36
1.29
2.15
1.36
1.29
****
1.74
(0.24)
1.60
(0.36)
1.49
1.86
(0.35)
2.26
2.53
(0.22)
(0.25)
STA
2.23
(0.35)
1.85
1.95
1.31
1.91
(0.27)
1.71
1.911
1.88
1.17
2.51
****
2.84
2.58
2.24
2.56
2.20
****
****
****
79
Appendix 7. (continued)
DAY 10.5
PIT
CONTROL
STA
9
10
16
22
30
33
52
78
85
98
0r1
1-2
2-3
3-k
311
2r3
2.37
2.38
2.08
1.58
1.28
1.32
1.32
2.148
3.0k
1.1414
2.149
****
1.146
1.211
1.143
1.32
1.11
1.37
1.26
1.16
1.58
1.19
2.17
1.40
1.32
1.141
2.414
1.27
2.09
2.114
2.114
2.23
2.20
2.08
2.07
1.145
1.71
1.43
****
****
2.141
1.149
1.06
1.56
1.314
1.314
1.141
1.30
1.12
1.50
1.17
1.18
1.42
1.145
2.23 1.52 1.311 1.29
(0.13) (0.25) (0.13) (0.15)
DAY
****
1.87
**
1.97
2.32
2.32
2.31
2.15
1.58
2.30
3.08
1.63
2.01
2.143
1.714
(0.50) (0.514) (0.52)
13.5
PIT
3rk
23
i2
1.16
1.12
1.63
2.23
3.06
0.93
1.07
1.53
2.20
1.05
1.29
1.15
2.00
1.37
1.25
1.16
1.73
1.51
2.114
3.09
3.32
2.67
1.95
2.28
2.314
1.59
****
****
148
1.72
1.93
1.20
1.06
149
2.514
1.81
60
2.11
714
2.50
1.90
1.79
1.20
1,65
7
314
146
****
76
1.614
79
2.10
2.58
86
2.71
3.00
3_14
le'2
1.148
1.19
1.23
1.60
****
****
2.51
2r3
0r1
0r1
2.114
CONTROL
STA
1r2
****
2.16 1.66 1.38 1.35
(0.35) (0.50) (0.38) (0.32)
****
2.214
1.10
1.37
1.38
1.32
1.111
1.29
1.1414
(0.314)
****
2.36
2.02
1.146
1.77
1.48
1.63
1.97
****
2.111
****
2.32
01
''''
''''
****
****
'''
2.59
2.69
2.69
2.75
2.68
1.90 2.60
(0.33) (0.51) (0.07)
DAY 19.5
PIT
CONTROL
0r1
1r2
2-3
3,14
3-11
2-3
1r2
0-1
13
25
36
2.22
1.60
2.18
1.614
2.614
2.11
2.31
2.10
2.72
1.36
1.141
1.114
1.23
2.33
2.39
1.87
1.39
1.82
1.35
1.69
2.34
2.61
2.65
1.92
2.'114
1.311
1.77
0.95
2.00
1.25
1.18
1.05
1.77
1.70
1.83
1.314
1.96
1.80
1.15
0.90
1.73
1.28
1.06
1.32
1.17
1.20
1.50
1.03
14Q
0.98
0.95
1.77
1.38
1.22
1.146
1.71
1.95
2.117
(0.38)
(0.52)
(0.147)
(0.22)
STA
1414
2.24
147
2.113
56
2.35
2.07
2.22
1.32
1.10
1.78
1.50
1.39
1.33
1.50
1.76
1.58
1.62
2.11
1.149
1(2
70
75
1.146
1.09
1.61
1.35
1.50
1.26
1.33
(0.26) (0.21) (0.27) (0.22)
**
2.1(2
2.311
2.77
****
2.32
DAY 23.5
PIT
CONTROL
0r1223314
311231r20
1.58
1.147
1.87
20
2.142
1.1414
1.67
1.27
1.17
1.1411
18
1.87
1.97
1.18
****
21
1.93
1.89
1.69
1.36
1.23
1.21
1.21
1.15
1.22
1.26
1.16
1.110
1.31
1.140
1.26
1.50
1.33
2.26
1.112
1.06
1.12
1.24
1.33
1,22
1.20
1.148
1.140
1.113
1.314
2.38
1.66
1.58
1.147
2.52
1.83
1.32
(0.13)
1.28
(0.16)
(0.113)
5Th
1
23
143
145
50
58
82
2.03
1.63
2.19
2.86
1.146
2.05
1.36
1.59
(0.36) (0.140) (0.19)
2.13
1.11
1.99
1.22
1.117
1.1414
1.18
1.33
1.19
1.36
1.28
1.27
1.53
1.67
1.75
2.83
2.55
2.30
2.35
2.27
2.50
2.05
2.73
1.98
1.148
1.53
2.014
2.29
1.66
(0.51) (0.25)
81
Appendix 8.
Weight percentage of mineral grains < 63 urn in
Means and standard deviations are given
sediment core sections.
for each section.
= missing data.
DAY 0
PIT
CONTROL
Or-i
i2
2r-3
3-14
3
17.16
18.88
13.514
10.81
14
'** 17.80
12.27
STA
93
114.31
11.91
914
13.25
13.83
14.73
-****
****
9.48
8.27
11.40
8.38
8.19
99
15.119
6.148
5.144
16.98
12.86
9.93
66
68
****
****
****
19.52
71
22.13
11
61
.****
****
10.78
9.62
13.55
(3.35)(14.11)( 3.09
7.95
13.16
7.03
7.87
ii. 514
9.13
7.13
3r-14
23
1r2
Oi
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
9.65
(
2.314)
DAY 1
PIT
CONTROL
STA
Or-i
1h2
23
3-4
3r44
7.82
6.58
8.77
7.57
8.47
8.38
****
12.21
'7.87
1)4.00
114.97
****
18.09
19.57
8
8.97
10.59
9.81
32
15.01
'7.51
38
15.48
16.19
15.16
16.36
10.66
'9.30
16.66
16.15
8.26
11.82
'8.15
511
55
59
65
80
88
97
13.99
9.53
9.97
****
18.52
6.54
114.09
11.19
13.97
11.32
11.911
8.63
3.77
8.68
14.89
10.81
7.311
16.05
9.30
****
6.03
8.142
16.21
13.60
9.89
10.22
8.145
( 3.08)(3.70)( 3.62)( 2.12)
I
2-3
114.17
11.51
****
11.72
8.22
13.11
15.118
13.57
11.91
(2.69)( 14.02)
i'-2
Or-i
****
****
****
****
****
****
****
****
****
****
****
****
82
Appendix 8. (continued)
DAY 2
PIT
CONTROL
Or-i
1r2
2r-3
3r-14
11.98
13.59
14.76
13.93
16.08
10.148
****
8.86
8.79
11.50
7.93
5.17
9.12
8.39
7.20
5.02
37
62
67
15.811
12.11
13.88
13.110
13.11
10.08
81
11.011
****
92
STA
5
12
15
17
211
14.1411
****
8.02
12.46
8.33
3r-1I
7.31
3.911
6.61
16.86
16.115
7.50
14.61
114.11
11.07
7.15
7.20
1.73)
(1.83)(2.67)( 2.73)(
1r-2
11.17 10.87
7.56 '7.75
9.47
9.35
8.12 10.21
8.53 19.014
9.59 11.56
11.61 16.42
5.96 13.52
10.13 12.15
12.63 114.92
6.711
10.32
6.78
7.17
2r3
9.117
12.59
12.62
13.78
0r1
15.147
''''
****
****
12.85
***
21.72
****
15.29
C 2.02)(3.43)(3.77)
DAY 3
PIT
CONTROL
STA
19
28
31
35
611
89
90
91
95
100
0i
1r-2
2r3
3r1l
3-11
2r3
1r-2
Or-i
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
****
18.711 12.86 12.38
9.511
15.27
6.30
12.16 114.75 9.57
9.26 13.28 11.83
16.00 13.55 10.78
13.68 10.61
8.41
17.21 13.30 12.73
**** .**** ,****
9.90
6.40
(
12.56
9.51
7.00
7.00
12.09
12.211
111.55
****
****
9.10
****
10.29
8.65
3.21)( 1.82)(2.34)( 2.22)
111.62
16.17 17.53
****
16.68 13.112
11.62 17.17 13.60
16.97 114.911 11.141
****
13.20 12.58
13.76 111.52
****
****
12.53
2.31)( 1.96)( 1.10)
111.71
(
13.149
111.96
****
****
'''
****
83
Appendix 8. (continued)
DAY 5
PIT
CONTROL
01
STA
1r2
26
20.79 13.88
6.72
15.07
17.26 12.31
29
10.116
9.01
39
18.20
9.58
12.20
12.00
8.07
7.76
9.09
9.53
8.95
9.69
111.66
9.50
6
111
51
57
15.911
69
77
87
15.11
(
2-3
3r11
6.113
11.92
6.21
3r1$
9.90 10.80
9.711
9.63
6.113
5.09
5.37 8.58
9.23
7.80
****
7.12
9.113
10.21
9.23
7.511
9.50
3.58)( 2.12)( 1.88)( 2.12)
DAY
****
11.01
****
11.38
11.82
10.16
13.52
9.94
16.89
10.35
12.05
lrt2
2r-3
3r11
2
27
16.112
****
15.82
10.83
10.58
10.1411
111
17e18 11.11
7.211
53
63
72
12.99 11.36 11.61
****
9.32
9.97
16.76 13.53
7.67
111.93
9.52 12.22
17.25 7.70 8.211
14.911 10.13
8.86
15.06
11.28
7.98
83
811
****
96
15.16
10.119
****
****
**
****
****
****
****
13.38
(1.93)( 2.67)(2.724)
7.5
PIT
Or-i
73
15.211
Or-i
11.91
CONTROL
STA
1r-2
****
13.50 11.87
9.05 13.38 111.87
10.73 10.80 10.03
****
9.711 10.58
****
8.72
9.78
7.117 18.59 12.65
11.80
7.81
2-3
3-M
23
12
****
13.99 13.117
****
16.59
10.50
13.70 12.611 17.19
11.112
11.311
111.05
9.211
9.113
11.01
13.18
13.18
'****
16.20
15.33
10.711
11.111
9.73
13.87
'8.83
8.22
9.90
****
10.16 10.76
( 2.27)( 1.67)( 2.72)( 2.38)
11.118
****
19.10
12.33
12.611
12.82
15.97
****
( 2.O2)(1.27)( 2.57)
0*'i
****
****
****
****
''''
****
****
****
****
****
84
Appendix 8. (continued)
DAY 10.5
PIT
CONTROL
STA
Oe1
1r2
2-3
9
19.47
10
16
22
30
33
52
78
85
98
19.22
12.12
9.33
16.21
10.148
7.78
10.60
9.19
20.08
13.63
10.83
13.63
7.71
17.81
18.61
12.116
11.70
10.09
15.98
****
19.67
'9.59
****
10.91
9.75
7.98
11.76
9.311
****
i2
0r1
****
****
****
****
17.26
13.69
''''
7.614
*'*
114.69
11.55
22.81
****
3-1l
2-3
9.80
111.79
8.149
10.97
7.99
8.70
8.79
8.87
20.21
21.11
8.53
3-1l
8.98
6.58
9.27
9.53
9.88
12.99
****
10.39
9.148
17.85 11.11
9.55
( 2.16)( i.148)( 1.116)( 1.70)
111.23
1I.148
8.37
10.81
'9.10
11.69
10.73
11.31
8.89
15.10
114.23
***'
****
****
****
**''
10.26
I
(
13.03 15.214
2.1114)( 11.75)( 14.19)
I
DAY 13.5
PIT
CONTROL
34
2r3
12
7.56
****
11.33
114.83
19.71
****
****
5.21
10.11
114.33
21.140
8.25
6.77
15.12
12.314
17.35
114.714
'6.25
8.21
11.82
8.33
12.62
18.86
9.119
7.92
8.'49
16.97
15.85
****
13.78
22.56
10.146
6.118
795
10.23
8.91
6.116
6.714
'6.18
9.75
12.22
6.38
9.29
11.88
01
1-2
17.39
149
13.68
15.82
22.78
5.28
15.72
60
111.68
714
STA
7
314
116
148
76
15.02
12.16
79
16.514
86
19.63
2-3
3r-14
13.26
****
8.82
****
6.143
3.146
6.911
16.141
8.60
11.58
8.80
( 3.22)( 1L30)( 3.87)( 2.98)
19.05
12.70
13.81
13.32
0r1
****
****
****
****
****
16.511
****
17.99
17.71
16.65
17.22
13.23 17.51
11.13)(
0.73)
2.95)(
( 2.93)(
9.111
85
Appendix 8. (continued)
DAY 19.5
PIT
CONTROL
STA
13
25
36
110
112
1111
117
56
70
75
Or1
1r2
2,3
3-1l
16.19
9.111
2.87
5.58
5,93
16.06
11.57
(i.96)( i.8't)(
8.23
8.57
2.60)( 2.60)
DAY
12
Or1
8.211
****
8.23
8.23
9.28
111.12
111.85
11.33
12.13
10.82
10.75
17.23
111.05
9.77 5.311
11.29 11.16 13.110
**** 10.32 '8.63
8.88
7.116
17.23 111.56
7.27
17.00 10.30
9.51 10.115
9.1111
19.00 12.63
7.06
15.81 111.118 10.36
5.10
111.711 10.87 10.08
8.811
i7.74 12.06 10.02 10.59
111.211
12.62
2r3
3i11
8.65
9.811
6.18
10.90
9.90
13.911
6.81
10.26
****
****
7.23
15.39
16.18 16.91
11.79 17.80
9.99 12.71
11.62
1
18
20
21
23
113
115
50
58
82
O'1
le-2
23
13.12 10.27 10.98
15.59 **** 8,110
19.88
9.73 5.28
15.09 9.65
553
18.12
8.01
9.110
8.88 5.811
12.89
15.89
9.72
7.69
12.60 8.66
7.11
17.59 18.76
9.89
19.28 111.911 10.10
16.52
1.29
15.07
18.117
111.90
18.70
111.811
13.10
111.26
2t-3
i.-2
0-1
13.1111
15.38
C 2.96)( 3.147)( 3.110)( 5.95)
23.5
PIT
CONTROL
STA
****
3-11
3-11
9.57
9.27
5.67
8.111
13.119
9.58
6.82
8.95
6.62
****
7.07
9.57 10.211
6.96 '7.110
7.78
5.37
12.20 9.58
9.90 20.97
9.58 9.72
8.110
8.97
8.113
6.00
9.31
****
9.03
11.11
7.88
8.29
3.112)(
2.O0)( 1.145)
C 2.65)(
16.01
10.16 11.110 15.511
2.03)( 1I.31)( 1l.97)( 2.31)
8.71
(
7.65 13.311
8.77 18.011
****
8.85
7.62 16.110
8.87 12.97
11.21 17.13
12.80 15.35
23.37 18.93
12.33
86
Raw pit dimension data f or each sampling date.
Appendix 9.
The first set of numbers in each block is for pits from faunal
treatments; the second Is f or sediment treatments.
d(0):
depth of pit at formation.
formation.
d(n):
eCU):
crossrstream width at
long-stream width at formation.
1(0):
depth on the date of sampling (n).
width at sampling.
1(n):
c(n): crossr'stream
long-stream width at sampling.
Dates are rounded to whole numbers for brevity.
d(0)
8
32
38
54
55
5.0
4.0
4.2
5.0
4.0
59
45
65
4.0
5.0
4.4
80
88
97
9.0
10.5
10.0
12.0
12.0
10.5
10.0
1(0)
9.0
9,5
10.0
12.0
11.0
10.3
9.0
9.0
9.0
10.0
10.0
14.0
9.0
9.5
9.5
9.5
9.0
10.5
10.0
10.0
11.0
9.0
10.0
9.0
9.5
10.0
10.0
8
4.0
32
38
54
55
14.5
59
5.0
65
80
14.0
88
97
eCU)
14.5
14.0
14.0
5.0
5.0
5.0
9.5
9,0
10.0
8.5
'9.0
10.0
8.0
d(1)
e(1)
2.0
2.5
2.0
2.0
2.0
2.0
2.5
2.0
2.0
2.2
14.0
13.0
12.0
17.0
15.0
13.5
12.0
14.5
2.0
2.5
2.5
2.5
2.7
2.5
2.0
2.5
2.0
2.0
114.5
114.0
12.0
14.0
114.0
16.0
15.0
17.5
12.0
13.0
12.0
12.0
1(1)
15.0
15.0
13.0
18.0
17.0
14.5
12.0
15.0
15.0
12.0
16.0
14.0
12.5
17.5
17.0
16.0
12.0
14.0
12.0
12.0
87
Appendix 9. (continued)
d(0)
5
12
15
17
214
37
62
67
14.5
6.0
6.0
14.0
40
14.0
3.5
92
14.0
14.0
14.0
5
14.0
81
12
15
17
211
37
62
67
6.0
6.0
14.0
14.0
14.5
81
3.5
3.5
4.0
92
11.0
d(0)
19
28
3.5
4.5
31
14.0
14.7
11.0
11.0
14.0
14.0
11.0
35
614
89
90
91
95
100
c(0)
1(0)
d(2)
c(2)
1(2)
10.0
12.0
12.0
10.0
10.0
9.0
9.5
10.0
9.0
9.0
10.0
11.0
12.0
9.0
10.0
9.0
10,0
10.0
9.0
10.5
2.0
2.0
2.0
1.5
18.0
15.0
18.0
17.0
16.0
12.0
0.0
15.0
15.0
17.0
17.0
13.0
17.0
12.0
0.0
13.0
114.0
114.0
14.0
14.0
10.0
9.0
11.0
9.0
9.7
10.0
9.0
10.0
9.0
9.0
10.0
9.0
12.0
9.5
10.0
9.0
10.0
9.0
10.0
10.5
2.0
1.5
1.7
1.5
1.5
2.0
2.0
16.0
18.0
16.5
16.0
18.0
15.0
13.0
1.7
114.0
17.0
19.0
17.0
13.0
16.0
16.5
13.0
13.0
13.0
13.0
2.0
2.0
2.0
2.0
2.0
1.5
1.5
1.5
2.0
114.0
114.0
14.0
12.0
15.0
15.0
12.0
14.0
1.5
114.0
13.0
12.0
16.0
14.0
13.0
13.0
12.0
15.0
12.0
1.0
114.0
31
14.0
35
5.0
3.5
11.5
11.0
14.0
95
100
1(3)
9.5
11.0
7.0
10.5
10.0
10.0
9.0
10.0
9.0
9.5
8.5
9.5
10.0
10.0
10.0
10.0
11.0
9.0
8.5
9.5
91
c(3)
9.0
9.0
9.5
10.0
9.0
10.0
9.5
9.0
9.0
3.8
5.0
5.0
13.5
13.0
d(3)
19
28
14.5
2.0
1.5
1(0)
9.0
89
90
2.0
0.0
2.0
2.0
1.5
c(0)
3.5
611
1.5
10.0
10.5
10.5
10.5
10.0
'9.5
11.0
'9.0
9.5
10.0
2.0
2.0
2.0
1.5
1.5
2.0
1.7
1.2
1.5
114.0
16.0
12.0
15.0
16.0
15.0
18.0
114.0
13.0
13.0
13.0
15.0
13.0
17.0
19.0
16.0
13.0
16.0
12.0
12.0
15.0
Appendix 9. (continued)
d(0)
6
'1.5
14
5.0
26
29
39
1L0
11.0
11.0
51
5.0
57
69
77
11
11.0
11.5
87
5.0
6
5.0
6.0
114
26
11.0
29
39
5.0
51
57
69
77
87
11.5
6.0
5.0
11.0
5.0
5.0
d(0)
2
5.0
27
11.0
111
53
63
72
73
83
3.7
5.0
11.0
11.5
'LU
811
11.5
11.5
96
5.0
2
27
5.5
5.0
111
11.0
53
63
72
73
83
6.0
3.5
11.5
5.0
811
4.0
4.0
96
5.9
c(0)
1(0)
d(5)
c(5)
1(5)
9.5
11.0
10.0
10.0
9.0
10.3
12.0
10.0
9.5
10.0
9.0
10.0
9.5
9.5
10.0
11.3
11.3
11.0
11.0
10.0
2.2
1.5
2.0
2.0
1.7
2.5
2.0
2.0
1.7
2.0
17.0
16.0
17.0
15.0
15.0
18.0
19.0
16.0
15.0
15.0
15.0
16.0
17.0
13.0
16.0
20.0
16.0
15.0
15.0
16.0
11.0
11.0
9.0
9.0
9.0
12.0
13.0
9.5
12.0
11.0
10.0
10.0
10.0
12.0
10.0
9.0
10.0
2.2
1.5
1.7
19.0
19.0
16.0
1.5
1.7
1.5
2.0
1.7
1.5
111.0
111.0
19.0
17.0
16.0
13.0
11.0
15.0
16.0
16.0
10.0
9.0
10.0
c(0)
1(0)
9.0
8.5
10.0
11.5
9.5
10.0
10.0
10.0
9.0
10.0
9.0
9.0
10.5
11.5
10.0
10.0
9.0
10.0
9.0
9.5
9.5
9.3
10.0
9.0
10.0
10.0
9.0
10.0
10.0
8.0
9.0
10.0
9.0
9.0
11.0
9.0
9.0
9.0
9.0
9.0
2.0
d(7)
1.5
17.0
18.0
.15.0
16.0
15.0
c(7)
15.0
0.0
1.2
0.0
15.0
1.7
1.5
1.5
1.5
1.5
1.7
19.0
15.0
20.0
111.0
0.0
15.0
15.0
0.0
2.0
1.5
1.2
2.0
1.5
1.5
1.5
1.2
1.7
1.2
18.0
12.0
15.0
19.0
15.0
17.0
16.0
11.0
15.0
20.0
18.0
16.0
1(7)
16.0
0.0
15.0
18.0
17.0
17.0
15.0
16.0
17.0
0.0
17.0
12.0
13.0
19.0
15.0
15.0
114.0
15.0
15.0
16.0
68
xipueddy 6
(P$flUT1.UO0)
(0)P
6
01
oc
91.
tT
0
Gt1
6
01.
Ott
O'ti
06
06
96
Oti
01i
(0)P
tiE
0
S11
9tr
O
0L
90L
00L
LL
06
09
0
(0)0
c11.
0EL
0
L1.
61
001.
00L
00L
0L
091
(EL)P
(EL)°
(EL)t
01
L
1.
oL1.
oci.
p01.
S01.
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001
0EL
SL
S01.
001.
00L
06.
001
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O'0
00?
01.
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061.
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001.
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c6
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09L
01
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001
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0hL
OL
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091.
091.
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09L
L
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00
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001.
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091.
00
S1
01.
01
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06
00
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091
091
00
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oo
061
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091.
G1.
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01.
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09L
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0SL
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S01
99
62.
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091.
001.
St1
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06
061
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6L
tT
0
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001
06
92.
01
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L
06
92.
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091.
06
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6
09
0S
09
091.
01
06.
001.
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0E1.
?1.
0?
00
S6
00L
00
0'L
0.0
09L
SL
06
06.
G6
0S
Oti
S6
0L1.
00
09L
0.0
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01
0L
00L
09
IIL
99
O'L
O'I.
S6
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9L
09
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06
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001.
0
6tr
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01i
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06
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2.
(01)1
0
OE
tiE
(01)°
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tr
6tt
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(0L)P
001.
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01r
91i
06
001.
001.
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91.
2.
00i
06
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Oti
9L
S9
96
(0)0
L0
00
09L
09L
O0Z
0.OZ
O'LL
091
O1
0'O.
OL
ozI.
otn.
091.
0.0
00
091.
00
90
Appendix 9. (continued)
d(0)
c(0)
12.0
13
25
11.0
11.0
9..5
36
11.5
10.0
110
1$5
112
11.5
9.0
9.0
1414
3.7
117
11.0
56
70
75
6.0
13
25
36
6.0
9.0
11.0
10.0
5.0
9.5
110
11.0
112
11.0
1411
11.0
117
11.5
56
70
75
5.0
10.0
10.0
10.0
11.0
12.5
14.0
11.5
11.0
13.0
11.0
9.0
9.0
14.5
9.5
9.0
d(0)
c(0)
11.0
1
5.0
18
11.0
20
14.0
9.0
10.0
9.0
1(0)
d(19)
c(19)
1(19)
11.0
10.0
11.0
9.0
10,0
10.0
11.0
13.0
9.0
9.5
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
12.0
10.3
10,0
10.0
10.5
11.0
11.0
11.0
10.0
9,5
0.0
0.0
0.0
0.0
0.0
0.0
1.0
0.5
1.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
19.0
17.0
15.0
0.0
20.0
16.0
0.0
1(0)
d(23)
c(23)
1(23)
0.0
0.0
0.0
0.0
1.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
17.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
21.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
20.0
0.0
0.0
10.5
9.5
6.0
5.0
11.0
11.0
10.0
10.0
12.0
15.5
10.0
11.0
10.0
11.0
10.5
11.5
13.0
82
11.5
9.0
9.0
1
5.0
9.0
9.5
10.5
10.0
10.0
10.0
21
11.0
23
14.0
113
11.5
115
11.0
50
58
18
20
11.0
21
11.0
23
11.0
10.0
9.0
10.0
113
11,5
9.5
115
11.0
50
5.0
58
14.0
82
11.0
10.0
10.0
12.0
9.0
4.0
9.0
10.0
10.0
11.5
11.0
9.5
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.0
0.0
0.0
114.0
0.0
0.0
0.0
0.0
0.0
0.0
19.0
91
Means and standard
Summary of pit dimension data.
Appendix 10.
Values for
deviations of pit dimensions are given for each date.
DO represent the grand means and deviations for all pits.
d(0):
depth of pit at formation.
formation.
d(n):
c(0):
cross-stream width at
long-stream width at formation.
1(0):
depth on the date of sampling (n).
width at sampling.
1(n):
c(n): cros&-stream
long-stream width at sampling.
Dates are rounded to whole numbers for brevity.
DATE
DO
d(0)
e(0)
14.48
9914
(1 06)
( 0 914)
9 93
(0 96)
9.69
(0 86)
14.38
9.81
9.98
(0.87)
(0.914)
(0.91)
14.18
(0.148)
9.145
(0.63)
(0.63)
Dl
14
146
(0.145)
D2
D3
D5
D7
D19
D23
c(n)
2 22
13 85
1(n)
10.05
(0 26)
(
1
68)
114
(
148
2 02)
114.60
114 114
(0.146)
(3.90)
('3.89)
9.80
(0.89)
1.72
(0.32)
114.15
114.10
(1.50)
(1.97)
16.30
15.80
(1.63)
(2.02)
1
70
14.68
10.22
('1.114)
10.31
('0.90)
1.85
(0.29)
9.57
(0.75)
9.58
(0.77)
1.37
114.30
114.10
(0.52)
(5.1414)
('5.09)
9.63
(0.70)
9.68
1.18
114.85
114.20
(0.71)
(0.514)
( 5.71)
( 5.75)
14.58
14.33
(0.47)
D13
d(n)
(0.63)
(0.71)
D1O
1(0)
14.87
10.145
10.55
0.97
15.140
114.95
(0.58)
(1.014)
(1.00)
(0.1414)
( 5.83)
(5.39)
141414
10.15
10.1414
0.13
2.55
2.75
(0.614)
('1.23)
('0.97)
(0.32)
(6.26)
(6.75)
14.38
10.23
1.75
('1.55)
10.38
('0.95)
0.10
(0.56)
(0.31)
(5.50)
1.85
(5.71)