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Aquatic ecoregions of the conterminous United States

January 1, 1987

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 (Omernik, 1987). This is a copy of the ecoregion coverage of Omernik (1987) with some item names modified. This is NOT the most recent version of the ecoregion definitions, which can be obtained from: Environmental Protection Agency, Western Ecology Division, Corvallis, OR at

Publication Year 1987
Title Aquatic ecoregions of the conterminous United States
DOI 10.3133/70046266
Authors J.M. Omernick
Publication Type Report
Publication Subtype USGS Unnumbered Series
Index ID 70046266
Record Source USGS Publications Warehouse