There are 6 level III ecoregions and 35 level IV ecoregions in Colorado, and many continue into ecologically similar parts of adjacent states. Explanations of the methods used to define the USEPA’s ecoregions are given in Omernik (1995), Omernik and others (2000), Griffith and others (1994), and Gallant and others (1989, 1995).Ĭolorado contains arid canyons, semiarid shrub- and grass-covered plains, alluvial valleys, lava fields and volcanic plateaus, woodland- and shrubland-covered hills, forested mountains, glaciated peaks, wetlands, and a variety of aquatic habitats. Level IV is a further subdivision of level III ecoregions. At level III, the continental United States contains 104 ecoregions and the conterminous United States has 84 ecoregions (United States Environmental Protection Agency, 2003). Level II divides the continent into 52 regions (Commission for Environmental Cooperation Working Group, 1997). Level I is the coarsest level, dividing North America into 15 ecological regions. A Roman numeral hierarchical scheme has been adopted for different levels of ecological regions. The relative importance of each characteristic varies from one ecological region to another, regardless of the hierarchical level. These phenomena include geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The approach used to compile this map is based on the premise that ecological regions can be identified through the analysis of the spatial patterns and the composition of biotic and abiotic phenomena that affect or reflect differences in ecosystem quality and integrity (Wiken, 1986 Omernik, 1987, 1995). 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 (Omernik and others, 2000). By recognizing the spatial differences in the capacities and potentials of ecosystems, ecoregions stratify the environment by its probable response to disturbance (Bryce and others, 1999). Level III and IV Ecoregions of Colorado-page size (541 kb)Įcoregions 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.
Level III and IV Ecoregions of Colorado-page size (541 kb).Level III and IV Ecoregions of Colorado-25" X 29" (931 kb).Level IV Ecoregions of Colorado-poster back side 46" X 36" (201 kb).Level IV Ecoregions of Colorado-poster front side 44.5" X 35.5" (3 mb).Instructions for applying symbology to ecoregions.Colorado Level IV Metadata and Colorado Level IV Symbology.Colorado Level III Metadata and Colorado Level III Symbology.Colorado GIS Data (shapefiles, metadata and symbology)
#Download usgs map for a region download#
To make sure you are using the most current ecoregion data, download shapefiles of ecoregions.
If you do not find a link to a state that has been completed, maps and GIS data are available on the Ecoregion FTP site and web content will be available shortly. Some Web content for Level IV Ecoregions is under construction.
#Download usgs map for a region pdf#
Additionally, each state section contains links to downloadable maps in PDF format, and files containing GIS datasets (shapefiles, metadata, and symbology data). Select a state for descriptive information about that state's Level III and IV ecoregions. Level III & IV Ecoregions by EPA Region.Level III & IV Ecoregions of the Continental United States.The USFS Topo Map Area of Interest covers the USFS National Forests and Grasslands. Orthoimagery data are typically high resolution images that combine the visual attributes of an aerial photograph with the spatial accuracy and reliability of a planimetric map.ĭata themes included are Boundaries, Geographic Names, Transportation, Contours, Hydrography, Land Cover, Shaded Relief, Trails, etc. USGS Imagery Topo is a tile cache base map of orthoimagery in The National Map and US Topo vector data. USGS Topo is a tile cache base map service that combines the most current data in The National Map (TNM), and other public-domain data, into a multi-scale topographic reference map.