The Aquatic Insects, with Emphasis on Trichoptera, of a Colorado Stream Affected by Coal Strip-Mine Drainage

摘要

Benthic sampling was conducted year-round over a 2 year period (July 1975-June 1977) on Trout Creek, a mountain stream in northwestern Colorado, to assess the effects of coal mine drainage on the stream insect community. Samples were taken monthly from rubble riffles above and below drainage from unreclaimed mine spoils. Unexpectedly, aquatic insects exhibited similar mean density and biomass values at each site and accounted for at least 95% of the total benthic standing crop above and below the mine. The number of insect taxa was similar and diversity index values did not vary significantly between sites. However, the community structure of the two sites did differ. This study points to the importance of community structure analysis in assessing effects of changes in environmental conditions in stream systems.