Stream Condition and Aquatic Macroinvertebrate Communities in an Appalachian Watershed Affected by Mixed Land Use and Legacy Mining

With increasing mixed land use in watersheds, understanding biological responses across spatially confounded stressors remains a practical management challenge. This study documents how commonly used biological indicators respond across a small but complex Appalachian watershed with variable proportions of forest, agricultural land, urban area, and a legacy of coal mining. Over four consecutive years, we evaluated sub-watershed and riparian land cover, discharge permit density, water chemistry, and physical habitat variables in multivariate analyses of taxonomic composition, while mixed-effects models assessed associations between water chemistry and physical habitat variables and composite or trait-based biological metrics. Low pH and elevated conductivity were associated with poorer biological condition, patterns consistent with multiple stressors related to legacy mining and urban development. Spatial and temporal variability further underscored the limitations of interpreting biological condition from land cover or single annual environmental measurements alone. These results support continued evaluation and mitigation of both acid mine drainage and urban stormwater stressors in mining-affected mixed land-use watersheds. More broadly, integrating composite indices with taxonomic and functional composition data provides a stronger basis for stressor interpretation and management prioritization where contemporary land uses and legacy disturbances overlap.