Chapter 4 Habitats
According to DeWan et al. (2010) , hydrologic regimes in the Coastal Plain are likely to be much more sensitive to changes in precipitation than to changes in temperature. Potential changes in the amounts and timing of precipitation have numerous and varied effects. Decreases in overall summer precipitation will likely cause reduced water flows, which will further contribute to warmer water temperatures and stress water quality. This is particularly important in the context of seasonal droughts, because nutrients may become concentrated and flush out of systems more slowly during low flow periods. Severe and prolonged droughts may decrease streamflow, decrease groundwater recharge, and increase evaporation, resulting in impacts to streams of this theme. Additionally, upstream headwaters and other small streams contributing flow to stream swamp communities could dry up, posing potential impacts to aquatic species and downstream flow regimes (DeWan et al. 2010; Karl et al. 2009; US EPA 2010) . Increased storm intensity can lead to flooding and increased stormwater runoff and erosion. With increased stormwater runoff there is also an increase in sediments, nutrients, and contaminants loading into streams and potential negative effects on biota. The increased loads could affect water quality and habitat for aquatic species, as well as drinking water for municipalities. Stormwater controls and retrofits will become increasingly important (Band and Salvesen 2009) . With a change in intensity and variability of rainfall, there are potential changes to stream flow patterns, channel hydrodynamics, lake levels, and the volume of groundwater from aquifers (Band and Salvesen 2009; US EPA 2010; Bakke 2008) . Channel hydrodynamics include flow regime, sediment transport, and overall channel design and can be altered by changes in storm frequency and intensity. Some streams in this aquatic system have a pattern of riffles, runs, and pools, and will exhibit overall changes to the quantity and quality of these habitats. Other streams and swamps have relatively slack water and comparatively few riffles and runs, and they may exhibit a shifting of sand bars. Storms may cause the felling of riparian trees, particularly in areas with narrow riparian areas. Increased woody debris in these streams will alter channel hydrodynamics as well as available habitat. An increase in the number of tropical events can lead to flooding, which causes many of the above-mentioned responses. Effects such as increased sediments and contaminants into aquatic systems, in addition to major disruption to channel design and hydrodynamics, potentially upset the physical, chemical, and biological structure of streams. Tropical events may also exacerbate problems associated with saltwater intrusion (Band and Salvesen 2009) . Sea level rise is likely to impact stream swamp communities, as the combined increase of inland flooding due to higher precipitation events coupled with elevated sea levels will exacerbate coastal inundation. Additionally, saltwater intrusion into freshwater streams is a possibility as sea level rises. The chemical composition of freshwater systems could change, and freshwater wetlands and swamps could be converted to salt marshes (Band and Salvesen 2009; US EPA 2010; Bakke 2008; Burkett et al. 2000) .
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2025 NC Wildlife Action Plan
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