Description: Ecoregions by state 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, EPA6003-89060, 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, Dynamac Corporation, co US EPA., 200 SW 35th Street, Corvallis, OR 97333, (541)-754-4465, email:griffith.glenn@epa.gov Alternate: James Omernik, USGS, co US EPA, 200 SW 35th Street, Corvallis, OR 97333, (541)-754-4458, email:omernik.james@epa.gov
Description: These data were generated as a cooperative project between the, Bureau of Land Management and the Bureau of Reclamation for the purpose of mapping sage brush and other land cover in a defined study area in and around the Cedar Creek Anticline within the Williston Basin. The study area falls within portions of NW South Dakota, SW North Dakota and SE Montana representing approximately 1,132,000 acres.PLEASE SEE THE PDF REPORT: Mapping Land Cover to Estimate Sage Grouse Habitat within the Cedar Creek Anticline and surrounding study area. September 2008. Patrick Wright & Dave Wegner; Science Applications International Corporation; Under Contract with the Bureau of ReclamationThe importance of sagebrush for many obligate species including sage grouse (Centrocercus urophasianus) is well documented. The objective of the current mapping effort is to utilize the newly developed methodology to determine the extent of sagebrush vegetation communities at a level of detail to assess community relationships in and around the Cedar Creek anticline. The 2007 high resolution color infrared orthophotography and the GIS compatible land cover land use map produced from the orthophotography can be used by researchers in many different ways to quantify and analyze the biodiversity of the study area.PLEASE SEE THE PDF REPORT: Mapping Land Cover to Estimate Sage Grouse Habitat within the Cedar Creek Anticline and surrounding study area. September 2008. Patrick Wright & Dave Wegner; Science Applications International Corporation; Under Contract with the Bureau of Reclamation