Chapter 4 Habitats
Table 4.2.9-1 Climate change compared to other threats to medium river communities. Threat Rank Order Comments
Residential development, particularly in steep slope areas, is of particular concern because of increased erosion. Most coolwater streams are larger streams and rivers and many have wider valleys where land use is more susceptible to being developed than on steeper sloped headwater streams. Row crops, agricultural grazing, and urban/suburban development are common. Increased impervious surfaces due to roads, parking lots, homes, and businesses increase the amount and speed of runoff being delivered into aquatic systems.
Development
1
1 Stormwater runoff will amplify the loading of nutrients, sediment, and contaminants into streams, rivers, and reservoirs, which may alter overall channel design; have a negative effect on biota due to habitat changes, increased turbidity, and chemical exposure; and affect drinking water quality (Band and Salvesen 2009) . 1 Runoff from urban areas often contains higher concentrations of nutrients (such as nitrogen and phosphorus), sediment, metals, hydrocarbons, and microbes. An increase in frequency and intensity of storms will contribute to increased pollution loading. Point and nonpoint sources—runoff and EDCs—are also threats. 1 Livestock access to streams contributes heavily to bank erosion, sedimentation, and nutrient input. 1 Riparian vegetation serves as nutrient input to the stream community and helps regulate stream temperature by providing shade. Lack of riparian vegetation or inadequate width of forested buffer can cause streambank erosion and sedimentation.
Sediment and Erosion
Pollution
Livestock in Streams
Lack of riparian vegetation
Loss of forest cover can cause increased erosion and sedimentation and negatively impact aquatic systems. Poorly constructed and maintained timber roads are another source of erosion.
Conversion to agriculture/silviculture
2
2 Irrigation and water supply withdrawals pose a threat to flow regime. Water withdrawals can be problematic, particularly in streams with already low 7Q10 flows because they may reduce available habitat for aquatic species. Decreased groundwater recharge between storms due to impervious surfaces leads to a decrease in stream baseflow.
Water Withdrawals
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2025 NC Wildlife Action Plan
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