MAP OF ECOREGIONS OF MISSISSIPPI
Citation:
Chapman, S. S., G. E. Griffith, J M. Omernik, J. Comstock, M. Beiser, AND D. Johnson. MAP OF ECOREGIONS OF MISSISSIPPI. U.S. Geological Survey, Washington, DC, 2004.
Description:
Ecoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources. They are designed to serve as a spatial framework for the research, assessment, management, and monitoring of ecosystems and ecosystem components. Ecoregions are directly applicable to many state agency activities, including the selection of regional stream reference sites, the development of biological criteria and water quality standards, and the establishment of management goals for nonpoint-source pollution. They are also relevant to integrated ecosystem management, an ultimate goal of many federal and state resource management agencies. The approach used to compile this map of Mississippi is based on the premise that ecological regions can be identified through the analysis of the patterns of biotic and abiotic phenomena that reflect differences in ecosystem quality and integrity. These phenomena include geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another regardless of the hierarchical level. A Roman numeral hierarchical scheme has been adopted for different levels of ecological regions. Level I and Level II divide the North American continent into 15 and 52 regions, respectively. At Level III, the continental United States contains 104 regions. Level IV is a further subdivision of the Level III ecoregions. Ecological and biological diversity of Mississippi is great. The state contains barrier islands and coastal lowlands, flat alluvial plains, large river floodplain forests, rolling and hilly coastal plains, and a variety of aquatic habitats. There are 4 Level III ecoregions (Southeastern Plains, Mississippi Alluvial Plain, Mississippi Valley Loess Plains, and Southern Coastal Plain) and 19 Level IV ecoregions in Mississippi and most continue into ecologically similar parts of adjacent states. The map of Level III and IV ecoregions of Mississippi was compiled at a scale of 1:250,000; it depicts revisions and subdivisions of earlier Level III ecoregions that were originally compiled at a smaller scale. Compilation of the map poster is part of a collaborative project primarily between the the U.S. EPA National Health and Environmental Effects Research Laboratory, U.S. EPA Region IV, U.S. Department of Agriculture's Natural Resources Conservation Service, and the Mississippi Department of Environmental Quality. This project is also associated with an interagency effort to develop a common framework of ecological regions for the US. Reaching that objective requires recognition of the differences in the conceptual approaches and mapping methodologies applied to develop the most common ecoregion-type frameworks, including those developed by the USFS and the NRCS. As each of these frameworks is further refined, their differences are becoming less discernible. Regional collaborative projects such as this one in Mississippi, where some agreement has been reached among multiple resource management agencies, are a step toward attaining consensus and consistency in ecoregion frameworks for the entire nation.