4.2 Aquatic Communities
4.2.8 Large Creeks/Small Rivers 4.2.8.1 Ecosystem Description
Small river communities represent the next stream order above headwater streams and typically consist of third- and fourth-order perennial large creeks or streams and small river systems. Tey may have fragmented habitats due to mill dams and other similar structures, but are generally too small to contain major operational hydroelectric dams. Species richness increases signifcantly in these systems and larger and more diverse fsh and mussel assemblage are found as compared to the headwater stream community. 4.2.8.2 Location of Habitat Small river communities can be found statewide. Tose located in the Mountain ecoregion may contain coolwater or coldwater systems depending on where they occur in the land- scape. Tose found in other areas of the state are warmwater systems, where water tem- peratures are persistently greater than 25°C (77°F). Examples of this community type include the Little River, Eno River, Swift Creek, Uwharrie River, Deep River, Upper Tar River, and Dan River. Te 2005 WAP described Piedmont riv- erine aquatic communities and adjacent terrestrial small wetland communities and food- plain forests which are components of this community, as priority habitats (see Chapter 5) (NCWRC 2005). 4.2.8.3 Problems Affecting Habitats Land Use. Aquatic systems in North Carolina have been threatened by a variety of pertur- bations 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 commer- cial development continues to threaten stream integrity because of related increases in sediment, bank erosion, and stormwater runof containing sediment and other potentially toxic materials. Riparian vegetation is critical to the overall stream and streambank stability and moder- ation of water temperatures. Lack of riparian vegetation or inadequate width of forested bufer can cause streambank erosion and sedimentation. In addition to stabilizing stream- banks, riparian vegetation serves as nutrient input to the stream community and helps regulate stream temperature by providing shade. Lack of sufcient vegetation cover con- tributes to rising water temperatures, especially where water depths are shallow enough that the entire water column is subject to solar heating.
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2015 NC Wildlife Action Plan
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