Lists of ecoregions in the United States may refer to:
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List of ecoregions in the United States (EPA)
This list of ecoregions in the United States provides an overview of United States ecoregions designated by the U.S. Environmental Protection Agency (EPA) and the Commission for Environmental Cooperation (CEC). The CEC was established in 1994 by ...
, United States Environmental Protection Agency system
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List of ecoregions in the United States (WWF)
The following is a list of ecoregions in the United States as identified by the World Wide Fund for Nature (WWF). The United States is a megadiverse country with a high level of endemism across a wide variety of ecosystems.
Terrestrial ecoregi ...
, World Wildlife Fund system
{{list of lists, environment
Ecoregions
An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of l ...