Stream water quality and benthic macroinvertebrate ecology in a coal-mining, acid-sensitive region

Acid mine drainage (AMD) and acid rain are important sources of impairment to streams in the Tygart Valley and Cheat River basins in north central West Virginia, USA. Due to a network of abandoned mined lands and bond forfeiture sites in this coal-mining region, AMD represents severe, but rather localized impacts to water quality. AMD is a consequence of the chemical oxidation of reduced geological minerals (sulfides) usually associated with coal during mining operations. The reactions produce aqueous solutions high in sulfates and dissolved metals when the minerals are exposed to the oxic environment through land disturbance. In addition, the weakly buffered and mostly acid producing to circum-neutral mineral geology of this region makes surface waters susceptible to the chemical consequences of acid rain. Acid rain forms when gaseous compounds of nitrogen and sulfur from fossil fuel combustion react with atmospheric moisture.;I tested a classification system based on water chemistry in streams of these two basins. Streams of the region ranged from very good water quality (reference type) to increasingly impaired by AMD (moderate to severe AMD types). Streams with soft water had characteristics associated with the impacts from acid rain, and streams with hard water were either natural occurrences or were influenced by alkaline materials injected into water to treat acid sources. A transitional water quality type was recognized, which was very difficult to characterize because of its gradation in chemistry across the spectrum from reference and hard water types to waters increasingly influenced by AMD.;It is commonly observed that benthic macroinvertebrates in streams from unpolluted waters are distributed continuously without being organized into discrete communities. The discreteness of water quality observed in this research, however, suggests that benthic macroinvertebrates ought not to be distributed continuously, but rather should correspond discretely to water quality types as distinct communities. Therefore, I tested the expectation that macroinvertebrate communities should be distributed in concordance with water quality types in the Cheat River basin. Multivariate models suggested that water quality types significantly structured macroinvertebrates. Measures of classification strength by water quality on community composition were weak, but significant. Indicator species analysis found several important macroinvertebrate genera that were linked especially to reference and soft water quality types.;In the Cheat River mainstem, benthic macroinvertebrate communities and a measure of stream ecosystem health were highly correlated to spatial and temporal inputs of AMD and thermal effluent. However, when these stressors occurred simultaneously, stream health and community structure did not recover with downstream improvements in water quality as they did when stressors occurred singly. In the Cheat River mainstem overall, AMD was responsible for most degradation, but AMD in combination with thermal effluent was also responsible for extensive loss of ecological integrity in the Cheat Canyon region. Consequently, local water chemistry accounts for the distributions of benthic macroinvertebrates in the Cheat basin. Therefore, macroinvertebrates may respond in predictable ways to restoration efforts that reduce harmful chemical constituents associated with acidic impacts. Large, watershed-scale attributes may be needed to explain variation in benthic macroinvertebrate communities not captured by local water quality types

Demographic characteristics of an avian predator, Louisiana Waterthrush (Parkesia motacilla), in response to its aquatic prey in a Central Appalachian USA watershed impacted by shale gas development

We related Louisiana Waterthrush (Parkesia motacilla) demographic response and nest sur- vival to benthic macroinvertebrate aquatic prey and to shale gas development parameters using models that accounted for both spatial and non-spatial sources of variability in a Central Appala- chian USA watershed. In 2013, aquatic prey density and pollution intolerant genera (i.e., pollu- tion tolerance value \u3c4) decreased statistically with increased waterthrush territory length but not in 2014 when territory densities were lower. In general, most demographic responses to aquatic prey were variable and negatively related to aquatic prey in 2013 but positively related in 2014. Competing aquatic prey covariate models to explain nest survival were not statistically significant but differed annually and in general reversed from negative to positive influence on daily survival rate. Potential hydraulic fracturing runoff decreased nest survival both years and was statistically significant in 2014. The EPA Rapid Bioassessment protocol (EPA) and Habitat Suitability Index (HSI) designed for assessing suitability requirements for waterthrush were posi- tively linked to aquatic prey where higher scores increased aquatic prey metrics, but EPA was more strongly linked than HSI and varied annually. While potential hydraulic fracturing runoff in 2013 may have increased Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness, in 2014 shale gas territory disturbance decreased EPT richness. In 2014, intolerant genera decreased at the territory and nest level with increased shale gas disturbance suggesting the potential for localized negative effects on waterthrush. Loss of food resources does not seem directly or solely responsible for demographic declines where waterthrush likely were able to meet their foraging needs. However collective evidence suggests there may be a shale gas dis- turbance threshold at which waterthrush respond negatively to aquatic prey community changes. Density-dependent regulation of their ability to adapt to environmental change through acquisition of additional resources may also alter demographic response

Linking Patterns in Endocrine-Disrupting Compounds to Storm Discharge and Yoy Smb Health in the Upper Juniata River Watershed

Population declines and disease incidence in smallmouth bass (Micropterus dolomieu) in the Susquehanna River basin have been linked to endocrine-disrupting compounds (EDCs) as a likely causative agent. Nothing is known about this link in the upper Juniat