A map of ecoregions of the conterminous United States has been compiled to assist managers of aquatic and terrestrial resources in understanding the regional patterns of the realistically attainable quality of these resources. The ecoregions are based on perceived patterns of a combination of causal and integrative factors including land use, land surface form, potential natural vegetation, and soils. A synoptic approach similar to that used to define these ecoregions is also useful for applications of the map. Initial efforts to use the framework are at the state level of resource management; they center on aquatic ecosystems - mainly attainable ranges in chemical quality, biotic assemblages, and lake trophic state.

Table includes notes on land-surface form, potential natural vegetation, land use, and soils. "Supplement to the Annals of the Association of American Geographers, volume 77, number 1." Accompanied by text: Map supplement, ecoregions of the conterminous United States. [9] p. ; 26 cm. On verso: Table 1, Characteristics of ecoregions in the conterminous United States as shown on the four component maps used to determine ecoregion boundaries.