Agenda - 11-27-1995 - C-1-b - Laserfiche WebLink

Browse Search

0,3,1 • Wetlands 49id the quality of water. Aquatic plants change inorganic mftnents into organic material, storing it in their leaves The stems, leaves, and roots of these plants also slow the,flow of water through a wetland, allowing the silt to settle out Consequently, wetlands protect downstream water resources from siltation and pollution. • Wetlands influence the quantity of water. They act as a sponges, retaining water during dry periods and hold it back during floods, thus keeping the water table high and reiatively stable. • Wetlands are important resources for overall environmental health and at wsity. They provide essential bree&ng, nesting, and feeding grounds and cover for may forms offish and wildlife. 77wese factors have the vdue of p ovubng general environmental health by creating recreational, research and educational sites, and adding to the aesthetics of the community. While there may be agreement regarding the functions that wetlands perform,there is less unanimity in defining such areas. No comprehensive inventory has been made of wetlands in Orange County, and detailed determination of wetland locations tends only to be made in the course of development planning which anticipates the need for formal permitting by the U.S. Army Corps of Engineers. That agency has established criteria for such determinations,based on soils,hydrology,and vegetation. Hydric Soils. Wetland soil is both the medium in which many of the wetland nutrient transformations take place and the primary storage of available nutrients for most wetland plants. It is often described as hyaric soil, defined by the U.S. Soil Conservation Service (SCS) as a soil that, in its undrained condition, is saturated, flooded or ponded long enough during the growing season to develop anaerobic(oxygenless) conditions that favor the growth and regeneration of hyrfrophAc vegetation (grows only in water). As shown on the preceding table, hydric soils are identical to alluvial soils,both in terms of soil types and their characteristics. National Wetlands Inventory. In 1971, the U.S. Fish and Wildlife Service began the National Wetlands Inventory (NWI), a systematic effort to classify and map America's wetlands. Working with a classification system based on soils, hydrology, and vegetation, and aerial photographs, biologists were able to map possible wedand areas. In Change County, identified areas in the NWI include only the stream system, certain marshy areas, lakes, and farm ponds. Although other wetlands exist, their absence from NWI mapping is more a function of their small size or specific characteristics, making them difficult to identify from aerial photographs. Wetland Communrties! More detailed information concerning the location of wetland area is available from two other sources. The fiat of these is LANDSAT satellite data, collected and analyzed as part of the Albemarle-Pamlico Estuarine Study,one of several studies undertaker through the U.S. Environmental Protection Agency's National Estuary Program.Land use and land cover characteristics for the 36-county estuarine region, including Orange County, were identified using the data. Among the land cover classes described in the study were bottornkmd h=dwood forests, a type of forested wetland found predominantly in the floodplains of streams and rivers,and characterized by tree species such as red maple and sweet gum which thrive in moisture-rich soils.