Koontz, J., D.G. Huggins, C.C. Freeman, D.S. Baker - Central Plains ...

Count SSS Intolerant Taxa
Count HM Intolerant Taxa
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Percent Hydroptilidae
Percent Burrowers
Figure 46. Box plots of macroinvertebrate metrics shown to be significantly different in
ANOVA testing for population differences. (a) Count of Taxa Intolerant to Suspended Solids
and Sediments (SSS). (b) Percent Hydroptilidae. (c) Count of Taxa Intolerant to Heavy Metals
(HM). (d) Percent Burrowers. Box area represents inner quartile range, while “whiskers”
represent the upper and lower observations.
Metric Correlations
The metrics selected after ANOVA testing were found to have significant relationships to many wetland
water quality parameters and floristic quality values. While correlation does necessarily mean
causation, most of the variability in the metrics were thought to be the result of either indirect or direct
biological responses associated with these water quality and floristic factors. Many important water
quality measures were correlated with multiple macroinvertebrate metrics, suggesting these metrics may
have broad application as water quality indicators for wetland systems.
Percent Hydroptilidae was significantly correlated with depth to flood (DTF), mean specific
conductivity, total organic carbon (TOC), dissolved organic carbon (DOC), and atrazine metabolite
desisopropylatrazine (DIA), and desethylatrazine (DEA) (Table 13). However, for many samples
collected during Phases I and II, the value of this metric was zero. Then these samples were removed
from the analysis, only mean conductivity, TOC, and DIA were found to be significantly correlated to
Percent Hydroptilidae. A robust regression model explained over 40% of the variation in Percent
Hydroptilidae (adjusted R 2 =0.41).
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