| Summary: | Thesis (M.Sc.)--Memorial University of Newfoundland, 2009. Biology Includes bibliographical references (leaves 7.1-7.19) Macroinvertebrate communities were sampled from 65 Newfoundland riffles from three geographic regions (the Avalon Peninsula, Terra Nova, and Gros Morne) in three seasons (summer, fall, spring). A suite of physical, chemical and land use variables were also measured. Differences in community composition across regions were found as well as large differences among seasons between sites sampled. Macroinvertebrate richness and abundance data were cross-examined with associated environmental variables to detect which ones were most related to macroinvertebrate community differences. UTM Easting, % macrophytes, % igneous rock, % local forest, nitrates, total Nitrogen and alkalinity were all highly correlated with trends in the macroinvertebrate community data. Urban communities differed from rural and pristine communities, the latter two community types being virtually indistinguishable. Temporal effects were examined to tease apart seasonal versus non-seasonal factors affecting the invertebrate-environment relationship. Changes in the frequency of occurrence of a few key taxa between years strongly impacted regional differences.
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