4.2 Aquatic Communities
Tere are few contiguous blocks of protected habitats in the Piedmont ecoregion so small river systems are threatened by land use practices that may increase stormwater runof of nutrients, sediment, and contaminants. Te increased loads could afect water quality and habitat for aquatic species, as well as drinking water supplies for municipalities (Band and Salvesen 2009) . Many rivers that were once free-fowing are now fooded by reservoirs, severely fragment- ing habitat and often isolating populations of species above and below the impoundment. Indirect efects to the unimpounded portions of the system include disruption of natural thermal and hydrologic regimes and a reduction in downstream fows. Tese impacts will have a negative infuence on aquatic habitat and will reduce base fow available for drinking water for downstream municipalities. Drought conditions over the past several years have required many municipalities to evaluate their water supply and capacity to meet demand. Residential and commercial growth in urban areas generates new demands for water supplies. An increase in the number of proposed reservoirs is a potential conse- quence of reduced water supply and increased demand. Water Quality. Erosion and the resultant sedimentation are the largest sources of nonpoint source pollution in most aquatic systems. Sources of erosion include disturbance from development activities and agriculture land uses. Residential development can increase erosion during the construction process and is a source of increased impervious surfaces in the watershed which can also increase erosion. Te Piedmont ecoregion is highly devel- oped and most watersheds have high percentages of impervious surfaces that contribute to increased runof, stream and bank erosion, pollution inputs, and increased fashiness of streams and rivers. Livestock access to streams contributes heavily to bank erosion, sedimentation, and nutrient input. Timber harvests and poorly constructed and main- tained timber roads are additional sources of erosion if proper controls are not used and maintained. Potential increased air temperatures and therefore increased water temperatures can lead to algal blooms in aquatic systems which diminishes stream oxygen availability. Te increased water temperature alone can cause a decline in DO and any decline in DO can lead to fsh kills, whether as a direct result of increased water temperature or as a second- ary efect of algal blooms (DeWan et al. 2010; Band and Salvesen 2009) . Many of the water quality and water quantity impacts resulting from climate change are analogous to impacts from economic development and population growth in North Carolina. Climate change is predicted to decrease rainfall and therefore, limit water supply. Growth and development, however, have been increasing and will continue to increase water supply demands. Historical stream fow patterns—already being altered due to rapid urbanization—are projected to be further altered due to climate change impacts.
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2015 NC Wildlife Action Plan
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