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Level IV Ecoregions of EPA Region 4

Metadata Updated: March 22, 2024

Ecoregions by EPA region were extracted from the seamless national shapefile. Ecoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources. They are designed to serve as a spatial framework for the research, assessment, management, and monitoring of ecosystems and ecosystem components. These general purpose regions are critical for structuring and implementing ecosystem management strategies across federal agencies, state agencies, and nongovernment organizations that are responsible for different types of resources within the same geographical areas. The approach used to compile this map is based on the premise that ecological regions can be identified through the analysis of patterns of biotic and abiotic phenomena, including geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another. A Roman numeral hierarchical scheme has been adopted for different levels for ecological regions. Level I is the coarsest level, dividing North America into 15 ecological regions. Level II divides the continent into 52 regions (Commission for Environmental Cooperation Working Group, 1997). At Level III, the continental United States contains 104 regions whereas the conterminous United States has 84 (U.S. Environmental Protection Agency, 2005). Level IV ecoregions are further subdivisions of Level III ecoregions. Methods used to define the ecoregions are explained in Omernik (1995, 2004), Omernik and others (2000), and Gallant and others (1989). Literature cited: Commission for Environmental Cooperation Working Group, 1997, Ecological regions of North America- toward a common perspective: Montreal, Commission for Environmental Cooperation, 71 p. Gallant, A. L., Whittier, T.R., Larsen, D.P., Omernik, J.M., and Hughes, R.M., 1989, Regionalization as a tool for managing environmental resources: Corvallis, Oregon, U.S. Environmental Protection Agency, EPA/600/3-89/060, 152p. Omernik, J.M., 1995, Ecoregions - a framework for environmental management, in Davis, W.S. and Simon, T.P., eds., Biological assessment and criteria-tools for water resource planning and decision making: Boca Raton, Florida, Lewis Publishers, p.49-62. Omernik, J.M., Chapman, S.S., Lillie, R.A., and Dumke, R.T., 2000, Ecoregions of Wisconsin: Transactions of the Wisconsin Academy of Science, Arts, and Letters, v. 88, p. 77-103. Omernik, J.M., 2004, Perspectives on the nature and definitions of ecological regions: Environmental Management, v. 34, Supplement 1, p. s27-s38. Comments and questions regarding Ecoregions should be addressed to Glenn Griffith, USGS, c/o US EPA., 200 SW 35th Street, Corvallis, OR 97333, (541)-754-4465, email:griffith.glenn@epa.gov Alternate: James Omernik, USGS, c/o US EPA, 200 SW 35th Street, Corvallis, OR 97333, (541)-754-4458, email:omernik.james@epa.gov

Access & Use Information

License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Dates

Metadata Date September 20, 2010
Metadata Created Date March 22, 2024
Metadata Updated Date March 22, 2024
Reference Date(s) May 1, 2010 (publication)
Frequency Of Update asNeeded

Metadata Source

Harvested from Environmental Dataset Gateway ISO Geospatial Metadata

Additional Metadata

Resource Type Dataset
Metadata Date September 20, 2010
Metadata Created Date March 22, 2024
Metadata Updated Date March 22, 2024
Reference Date(s) May 1, 2010 (publication)
Responsible Party U.S. Environmental Protection Agency, Office of Research & Development (ORD) - National Health and Environmental Effects Research Laboratory (NHEERL) (Point of Contact)
Contact Email
Guid {F9B998DD-E7CF-47AF-A38B-17F086FF54E3}
Access Constraints Use Constraints: None, Access Constraints: None
Bbox East Long -74.796314
Bbox North Lat 39.562647
Bbox South Lat 23.914498
Bbox West Long -91.945238
Coupled Resource
Frequency Of Update asNeeded
Harvest Object Id 3e79ccbe-5931-4479-a7b3-dada3073f38c
Harvest Source Id 9b3cd81e-5515-4bb7-ad3c-5ae44de9b4bd
Harvest Source Title Environmental Dataset Gateway ISO Geospatial Metadata
Licence https://edg.epa.gov/EPA_Data_License.htm
Licence Url https://edg.epa.gov/EPA_Data_License.htm
Lineage This lineage was generated by the FGDC CSDGM to 19139 transformation
Metadata Language eng; USA
Metadata Type geospatial
Old Spatial {"type": "Polygon", "coordinates": [[[-91.945238, 23.914498], [-74.796314, 23.914498], [-74.796314, 39.562647], [-91.945238, 39.562647], [-91.945238, 23.914498]]]}
Progress ONGOING
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True

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