Chapter 4 Habitats
4.2.7.4 Climate Change Compared to Other Threats 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 ).
Table 4.2.7-1 provides a review of expected climate change impacts in order of importance in comparison with other types of threats.
Table 4.2.7-1. Climate change compared to other threats to headwater streams/small creeks Threat Rank Order Comments
1 An increase in impervious surfaces due to roads, parking lots, homes, and businesses, increases the amount and speed of runoff being delivered into aquatic systems, and decreased groundwater recharge between storms leads to a decrease in stream baseflow. Runoff from urban areas often contains higher concentrations of nutrients (such as nitrogen and phosphorus), sediment, metals, hydrocarbons, and microbes.
Development
Streams in the Triassic Basin are particularly susceptible to erosion and are likely at greatest risk from erosion given proximity to many urban and suburban development centers. Erosion and the resultant sedimentation are the largest sources of nonpoint source pollution in most aquatic systems.
Erosion and Sedimentation
1
2 Headwater streams may shrink in habitat or extent. Higher temperatures and increased drought conditions will cause many headwater streams to dry up. 2 Lack of riparian vegetation or inadequate width of forested buffer can cause streambank erosion and sedimentation. In addition to stabilizing streambanks, riparian vegetation serves as a food/nutrient input to the stream community and helps regulate stream temperature by providing shade. 2 While bank vegetation is usually undisturbed, logging is a major threat to streams if proper erosion controls are not used and maintained. Poorly constructed and maintained timber roads also contribute to erosion.
Climate Change
Lack of riparian vegetation
Logging/Exploitation
Flood Regime Alteration
3
High and low flow extremes pose a threat.
4 Invasive plants in the riparian area often have negative impacts on stream systems by creating a monoculture with poor nutrient inputs, reducing bank stability, and allowing too much sunlight to infiltrate, causing warmer stream temperatures. Invasive aquatic
Invasive Species
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2025 NC Wildlife Action Plan
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