4.2 Aquatic Communities
the watershed. Livestock access to streams contributes heavily to bank erosion, sedimen- tation, and nutrient input. Timber harvests and poorly constructed and maintained timber roads are additional sources of erosion if proper controls are not used and maintained. Recent studies have shown that EDCs in treated wastewater can inhibit reproduction and cause feminization of mussels and fsh. Although little is known about the efects of EDCs, additional studies are being conducted to document the levels of EDCs in discharges, and measures are being identifed to reduce or eliminate EDCs from wastewater prior to dis- charge, should those discharge studies show increases in EDC levels (Conn et al. 2006; Kim et al. 2007; Kasprzyk-Hordern et al. 2008; Joss et al. 2006; Kolpin et al. 2002; Nowotny et al. 2007) . Aquatic species could experience shifts in their range or distribution and sensitive spe- cies may experience decline or extirpation due to changes in water quality and habitat. Piedmont headwater streams are already vulnerable to drought conditions with low DO or partial or complete drying of streams; climate-change induced drought will only increase this vulnerability. Aquatic species could become extirpated or may move further down- stream into higher order streams. Terefore, these systems may experience a change in species composition. Invasive Species. Invasive plants in the riparian area often have negative impacts on stream systems often times, by creating a monoculture with poor nutrient inputs, reduc- ing bank stability and allowing too much sunlight to infltrate, resulting in warmer stream temperatures. Invasive aquatic species, like the Asian Clam, may have negative efects on native species through competition for space and resources. Climate Impacts. Many of the water quality and water quantity impacts resulting from cli- mate change are analogous to impacts from economic development and population growth in North Carolina. Climate change is predicted to decrease rainfall and thereby limit water supply while growth and development have increased and continue to increase water supply demands. Historical stream fow patterns are projected to be altered due to climate change impacts; yet these patterns are already being altered due to rapid urbanization. An increase in impervious surfaces due to the proliferation of roads, parking lots, homes, and businesses increases the amount and speed of runof being delivered into aquatic systems. Increased air temperatures may lead to increased water temperatures and potentially lower DO levels because headwater streams tend to be small systems. Higher air and water tem- peratures can 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 tempera- tures but on a much more acute scale. Tese stream systems are vitally important to the overall health of the downstream watershed, yet are likely to experience potentially severe physical, chemical, and biological changes with temperature and DO alteration (DeWan et al. 2010; Karl et al. 2009; Band and Salvesen 2009) .
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2015 NC Wildlife Action Plan
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