摘要：Benthic macroinvertebrates and sediments were sampled in second- to fourth-order Tennessee Ridge and Valley streams and evaluated relative to urban land use and natural riparian cover. Site-specific estimates of EPT family richness (number of Ephemeroptera, Plecoptera, and Trichoptera families) ranged from 3 to 15. Urban land use in the watershed (from <1 to 27 %) was directly correlated with total suspended solids, sediment coverage, sediment depth, and oligochaete abundance. Watershed urban land use was inversely correlated with EPT family richness and relative abundances of EPT, filterers, and predators. Riparian forest cover was inversely correlated with total suspended solids, and total plant/wetland cover in the buffer was directly correlated with overall invertebrate taxa richness. Although natural riparian features appeared to have a positive influence on stream habitat quality and biotic conditions, correlations were stronger at the catchment scale. Relationships observed in this study underscore the negative effects of increased watershed urbanization on environmental conditions (more sedimentation) and benthic invertebrate assemblages (fewer pollution-sensitive insects, filterers, and predators) in small to midsize streams.
