Multiple stressors influence benthic macroinvertebrate communities in central Appalachian coalfield streams

Headwater streams impacted by surface coal mining and valley fill in the central Appalachian region of the eastern U.S. have characteristics not shared by reference-quality streams in the region. These include elevated salinity, often measured using specific conductance (SC) and often cited as a primary stressor of benthic macroinvertebrate communities. The objective of this study was to determine if benthic macroinvertebrate community composition differences from reference condition in mining-influenced streams could be attributed to potential stressors other than SC. Stream habitat characteristics were measured and calculated, and benthic macroinvertebrates were sampled from 12 central Appalachian streams. Multiple benthic macroinvertebrate community metrics, including Ephemeroptera density, richness, and composition were correlated strongly and negatively with SC. Predator density and scraper richness were correlated strongly and negatively with streamwater selenium concentrations. Clinger richness was correlated strongly and positively with large cobble-to-fines ratios in stream substrate and relative bed stability. These correlations are consistent with known ecotoxicological mechanisms revealed by prior studies. Improved understanding of how multiple habitat features are altered by mining and, in turn, impact community structure in headwater streams can inform water resource management in mining areas.