Science Inventory

LEVEL III ECOREGION:ECOREGIONS FOR THE MAIA STUDY REGION

Citation:

Description:

This data set is a geographic information system (GIS) coverage of aquatic ecoregions for the US Environmental Protection Agency (EPA) Mid-Atlantic Integrated Assessment (MAIA) Project. This coverage was produced from the USEPA Omernik Level III Ecoregions of the Conterminous United States. The approach used to compile this map is based on the premise that ecological regions can be identified through the analysis of the patterns and the composition of biotic and abiotic phenomena that affect or 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. Because of possible confusion with other meanings of terms for different levels of ecologic regions, a Roman numeral classification scheme has been adopted for this effort. Level I is the coarsest level, dividing North America into 15 ecological regions whereas at Level II the continent is subdivided into 52 classes. Level III is the hierarchical level shown on this map. This data layer is at a map scale of 1:7,500,000.

Record Details:

Record Type:DATA SET
Product Published Date:01/01/1987
Record Last Revised:12/10/2002
Record ID: 4712