Chapter 4 Habitats
can also be a secondary cause of increased impervious surfaces in the watershed. Livestock access to streams contributes heavily to bank erosion, sedimentation, 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 fish. Although little is known about the effects of EDCs, additional studies are being conducted to document the levels of EDCs in discharges, and measures are being identified to reduce or eliminate EDCs from wastewater prior to discharge, 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 species may experience decline or extirpation due to changes in water quality and habitat. Piedmont headwater streams are already vulnerable to drought conditions with low dissolved oxygen (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 downstream into higher order streams. Therefore, these systems may experience a change in species composition. Invasive Species. Invasive plants in the riparian area have negative impacts on stream systems often times, by creating a monoculture with poor nutrient inputs, reducing bank stability and allowing too much sunlight to infiltrate, resulting in warmer stream temperatures. Invasive aquatic species, like the Basket (Asian) Clam, may have negative effects on native species through competition for space and resources. Climate Impacts. 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 thereby limit water supply while growth and development have increased and continue to increase water supply demands. Historical stream flow 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 runoff 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 temperatures can lead to increased evaporation, which results in less flowing water available for aquatic species. Hot spells can have the same effect as overall increased air temperatures but on a much more acute scale. These 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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2025 NC Wildlife Action Plan
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