Chapter 4 Habitats
water temperature alone can cause a decline in DO, and any decline in DO can lead to fish kills, whether as a direct result of increased water temperature or as a secondary effect of algal blooms. This phenomenon may be increasingly expressed within reservoirs on large Piedmont rivers (DeWan et al. 2010; Band and Salvesen 2009) . 4.2.10.4 Climate Change Compared to Other Threats Comparing climate change to other ecosystem threats can help define short- and long-term conservation actions and recommendations. Sea level rise already impacts large rivers at their terminus along the Atlantic coast. Other climate change impacts may not be as severe a threat, but a combination of synergistic effects with other existing conditions could stress these systems to the point where several species are unable to persist. Table 4.2.10-1 provides a review of expected climate change impacts in order of importance in comparison with other types of threats. Table 4.2.10-1 Climate change compared to other threats to large river communities. Threat Rank Order Comments
1 Direct, secondary, and cumulative effects from development include increased sediment, bank erosion, and stormwater runoff containing sediment and other potentially toxic materials. 2 Alterations such as reduced flooding and impervious surfaces that increase flashy flow in combination with changes in precipitation will have a big effect on these systems. Alteration of hydrology due to dam creation and wetland draining are also affecting this habitat type. 2 Runoff from urban areas often contains higher concentrations of nutrients (such as nitrogen and phosphorus), sediment, metals, hydrocarbons, and microbes. Erosion and the resultant sedimentation are the largest sources of nonpoint source pollution in most aquatic systems. Increased stormwater runoff will amplify the loading of nutrients, sediment and contaminants. The increased loads could affect water quality and habitat for aquatic species, as well as drinking water for municipalities. Point and nonpoint sources—runoff and EDCs—are also threats. Confined animal operations and animal waste lagoon discharges are a potential source of contamination if not properly managed and maintained. In particular, nutrient loads have the potential to greatly increase with the construction of new poultry processing facilities on the coast. 3 Sea level rise, drought, increased storm activity, and higher temperatures are threats to large Coastal Plain rivers.
Development
Flood Regime Alteration
Pollution
Climate Change
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2025 NC Wildlife Action Plan
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