4.2 Aquatic Communities
Potential increased air temperatures and resulting increased water temperatures can lead to algal blooms in aquatic systems that diminish 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 secondary efect of algal blooms. Tese efects are highly likely, in addition to complete drying of streams during drought conditions, in Piedmont headwaters streams (DeWan et al. 2010; Band and Salvesen 2009) . Potential changes in precipitation will contribute to severe and prolonged droughts result- ing in decreased stream fow, decreased groundwater recharge, and increased evaporation. Reduced water fows will further contribute to warmer water temperatures and further stress water quality. Headwater streams could dry up, potentially leading to aquatic species extirpation (DeWan et al. 2010; Karl et al. 2009; Band and Salvesen 2009; Holman et al. 2010) . During droughts, recharge of groundwater will decline as the temperature and spacing between rainfall events increase. Responding by increasing groundwater pumping will further stress or deplete aquifers and place increasing strain on surface water resources. Increased water withdrawals for agriculture could further stress surface water resources and available aquatic habitat. Additionally, decreased groundwater recharge between storms due to impervious surfaces leads to a decrease in stream base fows. Runof from urban areas often contains higher concentrations of nutrients (such as nitrogen and phosphorus), sediment, metals, hydro- carbons, and microbes. An increase in frequency and intensity of storms due to climate change will have a similar impact on stream systems by increasing pollutant loading. Terefore, challenges to water quality and water quantity as related to climate change are similar to those being confronted to accommodate growth and development. Adaptation strategies for water resource management could limit negative efects of both climate change and continuing development (Band and Salvesen 2009) . Storms. Increased storm intensity can lead to periodic fooding and therefore, increased stormwater runof and increased erosion. With increased stormwater runof there is an increase in loading of sediments, nutrients, and contaminants into streams and potential negative efects on biota. With a change in intensity and variability of rainfall, there are potential changes to stream fow patterns and channel hydrodynamics (Band and Salvesen 2009; Holman et al. 2010; Bakke 2008) . An increase in the number of tropical events can lead to fash fooding, which causes many of the above-mentioned responses. Efects such as increased sediments and contaminants into aquatic systems, in addition to major disruption to chan- nel design and hydrodynamics, potentially upset the physical, chemical, and biological structure of streams (Band and Salvesen 2009) .
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2015 NC Wildlife Action Plan
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