Chapter 4 Habitats
4.2.8 Large Creeks/Small Rivers 4.2.8.1 Ecosystem Description
Large creeks and small river communities represent the next stream order above headwater streams and typically consist of third- and fourth-order perennial systems. These aquatic systems have a DA of 200 to 3,800 square miles. They may have fragmented habitats due to mill dams and other structures but are generally too small to contain major operational hydroelectric dams. Species richness increases significantly in these systems, and larger and more diverse fish and mussel assemblages are found as compared to the headwater stream community. 4.2.8.2 Location of Habitat Small river communities can be found statewide. Those located in the Mountain ecoregion may contain coolwater or coldwater systems depending on where they occur in the landscape. Those found in other areas of the state are warmwater systems, where water temperatures are persistently greater than 25°C (77°F). Examples of this community type include the Little River, Eno River, and Swift Creek in the Neuse Basin, Upper Tar River, and portions of the Uwharrie River, Deep River, and Dan River. Adjacent terrestrial habitats such as small wetland communities and floodplain forests are components of this community and are described in Section 4.3 (wetlands) and Section 4.4 (terrestrial uplands). 4.2.8.3 Problems Affecting Habitats Land Use. Aquatic systems in North Carolina have been threatened by a variety of perturbations in the past, and many of those same threats continue today. Converting land uses from natural forest to agriculture or silviculture production and residential and commercial development continues to threaten stream integrity because of related increases in sediment, bank erosion, and stormwater runoff containing sediment and other potentially toxic materials. Riparian vegetation is critical to the overall stream and streambank stability and moderation of water temperatures. 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 nutrient input to the stream community and helps regulate stream temperature by providing shade. Lack of sufficient vegetation cover contributes to rising water temperatures, especially where water depths are shallow enough that the entire water column is subject to solar heating. There are few contiguous blocks of protected habitats in the Piedmont ecoregion, so small river systems are threatened by land use practices that may increase stormwater runoff of nutrients, sediment, and contaminants. The increased loads could affect water quality and habitat for aquatic species, as well as drinking water supplies for municipalities (Band and Salvesen 2009) .
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2025 NC Wildlife Action Plan
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