4.2 Aquatic Communities
riparian vegetation. Aquatic systems have been under threat from a variety of perturba- tions in the past and many of those continue today. 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 alter seasonal precipitation patterns that can limit water supply. Growth and develop- ment, 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. Potential changes in precipitation may have numerous and varied efects. Severe and pro- longed droughts may decrease stream fow, decrease groundwater recharge, and increase evaporation, resulting in impacts to medium rivers. A decrease in overall summer precip- itation will likely cause reduced water fows, which will contribute to warmer water tem- peratures and further stress water quality. Tis is particularly important in the context of seasonal droughts because during low-fow periods, nutrients may become concentrated and fush out of systems more slowly (DeWan et al. 2010; Karl et al. 2009; Band and Salvesen 2009; Holman et al. 2010) . Increased air temperatures may lead to increased water temperatures and potentially lower DO levels. Higher air and water temperatures can also lead to increased evaporation, which results in less fowing water available for aquatic species. Hot spells can have the same efect as overall increased air temperatures but on a much more acute scale. Algal blooms are possible in these systems and can exacerbate DO problems, particularly when fows are low (DeWan et al. 2010; Karl et al. 2009; Band and Salvesen 2009; Holman et al. 2010) . An increase in frequency and intensity of storms due to climate change will have a simi- lar impact on stream systems by increasing pollutant loading. Increased storm intensity that causes fooding can lead to increased stormwater runof and erosion. With increased stormwater runof, there is an increase in loading of sediments, nutrients, and contami- nants into streams and potential negative efects on biota, such as fsh kills. With a change in intensity and variability of rainfall, there are potential changes to streamfow patterns, channel hydrodynamics, and the volume of groundwater (Band and Salvesen 2009; Holman et al. 2010; Bakke 2008) . Drought conditions over the past several years have required many municipalities to eval- uate 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 and surface water withdrawals is a potential consequence of reduced water supply and increased demand.
Because of potential changes in storm frequency and intensity, it is likely that channel hydrodynamics will be altered. Associated with channel hydrodynamics are changes in
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2015 NC Wildlife Action Plan
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