4.3 Wetland Natural Communities
Floodplain systems in the Coastal Plain ecoregion may be associated with blackwater rivers (originating in the Coastal Plain) or brownwater rivers (originating in the Piedmont or Mountains but fowing into the Coastal Plain). Floodplains in the Coastal Plain are typically characterized as broad alluvial features that may be inundated for prolonged periods every year with low gradient meandering streams that terminate in tidal estu- aries (Hupp 2000) . Separate community descriptions are provided for the blackwater and brownwater foodplains (see Sections 4.3.3 and 4.3.4, respectively) because of their unique characteristics. In the Piedmont and Sandhills ecoregions, foodplain forests generally do not contain the signifcant recognizable elevation diferences seen in the larger coastal foodplain systems. In these smaller foodplains, the relief and size of the fuvial landforms (levees, sloughs, and ridges) that diferentiate the communities in large foodplains become smaller and harder to fnd (Schafale and Weakley 1990) . In larger and more expansive examples of these food- plains, the forest canopy contains a good mixture of bottomland and mesophytic (moder- ately moisture tolerant) plant species. Floodplain forests of the Mountain ecoregion are relatively narrow and do not contain well-developed levees, sloughs, and ridges. Smaller high gradient streams often do not have representative foodplains, but instead have riparian zones embedded within other habi- tat types such as isolated patches of various wetland communities (Schafale and Weakley 1990) . Mountain foodplains are subject to sporadic high-intensity food events of short duration. 4.4.5.2 Location of Habitat Floodplain forests of some type are found beside most rivers and streams in the Piedmont and Sandhills ecoregions. Tey are of varying widths, depending on the topography of land adjacent to the river, and the transition between foodplain and upland forest is often gradual. Mountain foodplains are generally restricted to larger streams and rivers with relatively low gradients of the valley landscape. 4.4.5.3 Problems Affecting Habitats Flooding. Natural foodplains are biologically productive and diverse ecosystems that are among the most threatened due to habitat alteration, fow and food control, invasive species, and pollution (Tockner and Stanford 2002) . Te condition of foodplain forests of all types has been greatly reduced in recent years throughout North Carolina and the entire southeast (Weller and Stegman 1977; Schafale and Weakley 1990) by a variety of anthropogenic factors. Factors that impact these systems in North Carolina include fooding regime patterns that have been changed by dams and other development, habitat fragmentation, changes in water chemistry and organic matter loads, increased nitrogen from agricultural and
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2015 NC Wildlife Action Plan
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