4.2 Aquatic Communities
4.2.11 Stream Swamp Systems 4.2.11.1 Ecosystem Description
Small stream swamp communities are found in the lower Coastal Plain ecoregion and rep- resent aquatic habitats of small to medium streams, larger swamp systems, and artifcial ditches that are not included in the large river community description. Floodwaters gener- ally drain slower in these systems, thereby increasing the duration and extent of interface between the aquatic habitat and adjacent land as compared to foodplain communities that are found in other ecoregions. Substrate in these systems is typically sand or organic matter and many waters have high quantities of tannins. Although ditches are artifcial habitats, they are included in this theme because they frequently have hydrologic con- nection to natural streams and over time the aquatic communities resemble these natural systems. 4.2.11.2 Location of Habitat Examples of this community type include Town Creek, Great Coharie Creek, and Juniper Creek in the Coastal Plain. Priority habitats identifed in the 2005 WAP that are similar to this community include the Mid-Atlantic Coastal Plain Riverine Aquatic Communities and Tidal Swamp Forest and Wetlands (see Chapter 5) (NCWRC 2005) . 4.2.11.3 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. For example, ditches used to drain stream swamp communities will alter local hydrology, eliminate aquatic habitats, and alter terrestrial communities that depend on hydrologic input from the swamp, and can be a conduit for saltwater intrusion, depending on landscape position. Converting land uses from natural forest to agriculture or silviculture production and residential and commercial development continues to threaten stream integrity. Te threat comes from related increases in sediment, bank erosion, and stormwater runof containing sediment and other potentially toxic materials. Floodplains and wetlands associated with stream swamp communities are natural features designed for food control and dissipat- ing foodwaters. Floodplain development interferes with this natural capacity and worsens downstream fooding, scour, and erosion. Riparian vegetation is critical to the overall stream and streambank stability and mod- eration of water temperatures. Riparian areas include land adjacent to water bodies (e.g., foodplains) and are critical to the overall stream and streambank stability. In addition to erosion control, riparian areas allow for sediment and pollutant deposition (by dissipat- ing energy from runof and allowing for fltration); infltration of water runof to allow for
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2015 NC Wildlife Action Plan
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