Ecoregions and Subregions of Iowa: A Framework for Water Quality Assessment and Management

Ecoregion frameworks are valuable tools for inventorying and assessing environmental resources, for setting resource management goals, and for developing biological criteria and water quality standards. In a collaborative project between the Iowa Department of Natural Resources (DNR) and the U.S. Environmental Protection Agency (EPA), we have refined boundaries of the EPA\u27s five ecological regions of Iowa and defined six subregions of the Western Corn Belt Plains ecoregion within the state. Lists of candidate stream reference sites have been developed to date for the seven largest regions, and the sites were visited and evaluated by Iowa DNR and U.S. EPA personnel to determine their suitability for sampling aquatic biota. The Iowa DNR plans to use the ecoregions and reference sites to better understand regional variations in stream quality, to help define best-attainable conditions, to develop biological criteria, and as a framework to report on water quality