Metadata: Identification_Information: Citation: Citation_Information: Originator: U.S. Environmental Protection Agency Publication_Date: 200506 Title: Omernik’s Level III Ecoregions of the Continental United States Publication_Information: Publication_Place: Reston, VA Publisher: National Atlas of the United States Online_Linkage: Description: Abstract: This map layer shows Omernik’s Level III ecoregions, derived from a 1:7,500,000 map created by J.M. Omernik in 1987 and from refinements of Omernik's framework that were made for other projects. Ecoregions describe areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources. Omernik’s ecoregions are based on the premise that a hierarchy of ecological regions can be identified through the analysis of the patterns and the composition of both living and nonliving phenomena, such as geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology, that affect or reflect differences in ecosystem quality and integrity. All the characteristics are considered when determining ecoregions, but the relative importance of each characteristic may vary from one ecoregion to another. Level III is the most detailed level available nationally for this system of ecoregions. Purpose: These data are intended for geographic display and analysis at the national level, and for large regional areas. The data should be displayed and analyzed at scales appropriate for 1:7,500,000-scale data. No responsibility is assumed by the National Atlas of the United States in the use of these data. Supplemental_Information: Detailed descriptions of the ecological regions represented in this map layer are available from the U.S. Environmental Protection Agency (EPA), Western Ecology Division at: . EPA also offers data of Omernik’s Level III Ecoregions on the same site; the file includes the same ecoregions as are available through the National Atlas but uses EPA shorelines and State boundaries. A bibliography of ecoregion/biocriteria publications, called Ecoomr_Biblio.txt, is bundled with the downloadable data. Each reference in the bibliography has a code; the codes are used for any citations in this metadata file. Ecoregions denote areas of general similarity in ecosystems and the type, quantity, and quality of environmental resources; they are designed to serve as a spatial framework for the research, assessment, management, and monitoring of ecosystems and ecosystem components. By recognizing the spatial differences in the capacities and potentials of ecosystems, ecoregions stratify the environment by its probable response to disturbance (BR-1-98). These general purpose regions are critical for structuring and implementing ecosystem management strategies across Federal agencies, State agencies, and nongovernmental organizations that are responsible for different types of resources within the same geographic areas (OM-1-00, OM-1-04). The approach used to compile these ecoregions is based on the premise that ecological regions are hierarchical and can be identified through the analysis of the spatial patterns and composition of biotic and abiotic phenomena that affect or reflect differences in ecosystem quality and integrity (WI-1-86, OM-1-87, OM-1-95, OM-1-04). These phenomena include geology, physiography, vegetation, climate, soils, land use, wildlife, water quality, and hydrology. In the regionalization process, the full range of characteristics is examined and integrated at each scale or level of resolution. The relative importance of each characteristic varies from one ecological region to another regardless of the hierarchical level. Level I is the coarsest level of the hierarchy, dividing North America into 15 ecological regions. Level II divides the continent into 52 regions (CE-1-97). At level III, the continental United States contains 104 ecoregions, with the conterminous United States having 84 (US-1-03). More detailed level IV ecoregions have been delineated, or are in the process of being mapped, for approximately 85 percent of the conterminous United States. Since 1994, when the National Interagency Technical Team (NITT) was formed to develop a common framework of ecological regions (MM-1-01), efforts have been made to include all of the major federal resource management agencies in the level IV ecoregion mapping projects. The goal of each of these collaborative projects has been to attain consensus across agencies and ultimately to develop a consistent ecoregion framework for the entire nation. Because the collaborative projects to map level IV ecoregions often result in refined level III boundaries, the map of level III ecoregions is periodically revised. Likewise, much of the recent work to refine level III boundaries and define level IV ecoregions has resulted in slight differences between these two levels and the coarser level I and II regions mapped earlier by the CEC. Level IV ecoregions data and maps can be accessed through the Environmental Protection Agency Level IV Ecoregions page at . Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 200302 Currentness_Reference: Publication date of primary source material Status: Progress: Complete Maintenance_and_Update_Frequency: Irregular Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: 178 East_Bounding_Coordinate: -66 North_Bounding_Coordinate: 53 South_Bounding_Coordinate: 25 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: biota Theme_Keyword: environment Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: Ecoregions Theme_Keyword: Omernik’s ecoregions Theme_Keyword: Ecological regions Theme_Keyword: Ecosystems Theme_Keyword: Regional ecology Theme_Keyword: Ecosystem geography Theme_Keyword: Mapping Place: Place_Keyword_Thesaurus: None Place_Keyword: United States Place: Place_Keyword_Thesaurus: U.S. Department of Commerce, 1987, Codes for the Identification of the States, the District of Columbia and the Outlying Areas of The United States, and Associated Areas (FIPS 5-2): Washington, DC, National Institute of Standards and Technology. Place_Keyword: Alabama Place_Keyword: Alaska Place_Keyword: Arizona Place_Keyword: Arkansas Place_Keyword: California Place_Keyword: Colorado Place_Keyword: Connecticut Place_Keyword: Delaware Place_Keyword: District of Columbia Place_Keyword: Florida Place_Keyword: Georgia Place_Keyword: Idaho Place_Keyword: Illinois Place_Keyword: Indiana Place_Keyword: Iowa Place_Keyword: Kansas Place_Keyword: Kentucky Place_Keyword: Louisiana Place_Keyword: Maine Place_Keyword: Maryland Place_Keyword: Massachusetts Place_Keyword: Michigan Place_Keyword: Minnesota Place_Keyword: Mississippi Place_Keyword: Missouri Place_Keyword: Montana Place_Keyword: Nebraska Place_Keyword: Nevada Place_Keyword: New Hampshire Place_Keyword: New Jersey Place_Keyword: New Mexico Place_Keyword: New York Place_Keyword: North Carolina Place_Keyword: North Dakota Place_Keyword: Ohio Place_Keyword: Oklahoma Place_Keyword: Oregon Place_Keyword: Pennsylvania Place_Keyword: Rhode Island Place_Keyword: South Carolina Place_Keyword: South Dakota Place_Keyword: Tennessee Place_Keyword: Texas Place_Keyword: Utah Place_Keyword: Vermont Place_Keyword: Virginia Place_Keyword: Washington Place_Keyword: West Virginia Place_Keyword: Wisconsin Place_Keyword: Wyoming Access_Constraints: None Use_Constraints: None. Acknowledgment of the U.S. Environmental Protection Agency and (or) the National Atlas of the United States of America would be appreciated in products derived from these data. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: James M. Omernik Contact_Organization: U.S. Environmental Protection Agency, Western Ecology Division Contact_Address: Address_Type: Mailing and physical address Address: 200 SW 35th Street City: Corvallis State_or_Province: OR Postal_Code: 97333 Country: USA Contact_Voice_Telephone: 541-754-4458 Contact_Facsimile_Telephone: 541-754-4716 Contact_Electronic_Mail_Address: omernik.james@epa.gov Native_Data_Set_Environment: SunOS UNIX, ARC/INFO version 8.3. Cross_Reference: Citation_Information: Originator: James M. Omernik Publication_Date: 1987 Title: Ecoregions of the conterminous United States (map supplement) Edition: 1 Geospatial_Data_Presentation_Form: Map Series_Information: Series_Name: Annals of the Association of American Geographers Issue_Identification: 77(1) Publication_Information: Publication_Place: Washington, DC Publisher: Association of American Geographers Cross_Reference: Citation_Information: Originator: USDA Forest Service Publication_Date: 200403 Title: Bailey’s Ecoregions and Subregions of the United States, Puerto Rico, and the U.S. Virgin Islands Geospatial_Data_Presentation_Form: Map Publication_Information: Publication_Place: Reston, VA Publisher: National Atlas of the United States Online_Linkage: Online_Linkage: Data_Quality_Information: Logical_Consistency_Report: No checks for topological consistency were performed on this map layer. Completeness_Report: This map layer includes Level III ecoregions information for the conterminous United States and Alaska. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Omernik, J.M. Publication_Date: 2003 Title: Level III Ecoregions of the continental United States Geospatial_Data_Presentation_Form: Vector digital data Publication_Information: Publication_Place: Corvallis, OR Publisher: U.S. Environmental Protection Agency Online_Linkage: Source_Scale_Denominator: 7500000 Type_of_Source_Media: Online Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 200302 Source_Currentness_Reference: Publication date Source_Citation_Abbreviation: US Ecoregions Source_Contribution: Spatial and attribute information Source_Information: Source_Citation: Citation_Information: Originator: Omernik, J.M. Publication_Date: 2000 Title: Ecoregions of North America Geospatial_Data_Presentation_Form: Vector digital data Publication_Information: Publication_Place: Corvallis, OR Publisher: U.S. Environmental Protection Agency Online_Linkage: Source_Scale_Denominator: 12500000 Type_of_Source_Media: Online Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2000 Source_Currentness_Reference: Publication date Source_Citation_Abbreviation: NA Ecoregions Source_Contribution: Spatial and attribute information Source_Information: Source_Citation: Citation_Information: Originator: National Atlas of the United States Publication_Date: 200506 Title: State Boundaries of the United States Publication_Information: Publication_Place: Reston, VA Publisher: National Atlas of the United States Online_Linkage: Source_Scale_Denominator: 2000000 Type_of_Source_Media: Online Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1972 Ending_Date: 2005 Source_Currentness_Reference: Ground condition Source_Citation_Abbreviation: Atlas-States Source_Contribution: Spatial information Process_Step: Process_Description: The US Ecoregions and NA Ecoregions files were downloaded and reprojected to a Lambert Azimuthal Equal Area projection using ArcGIS 9.0. The shorelines in US Ecoregions were deleted. Alaska was clipped from in NA Ecoregions, placed in a new file, and the shorelines were deleted. The resulting files were combined along with shorelines from the Atlas-States map layer. Line work was cleaned and adjusted. The polygon attribution from US Ecoregions and NA Ecoregions was copied into the data and checked. Source_Used_Citation_Abbreviation: US Ecoregions Source_Used_Citation_Abbreviation: NA Ecoregions Source_Used_Citation_Abbreviation: Atlas-States Process_Date: 200503 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains Point_and_Vector_Object_Count: 3075 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.000278 Longitude_Resolution: 0.000278 Geographic_Coordinate_Units: Decimal degrees Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: GRS1980 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257222 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: Ecoregion (described by ecoomrp075.dbf) Entity_Type_Definition: A region that denotes an area of general similarity in ecosystems and in the type, quality, and quantity of environmental resources. The polygons in this map layer represent Omernik Level III ecoregions. Entity_Type_Definition_Source: National Atlas of the United States Attribute: Attribute_Label: Shape Attribute_Definition: The representation of the entity in the data. Attribute_Definition_Source: National Atlas of the United States Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: Polygon Enumerated_Domain_Value_Definition: 2-dimensional element Enumerated_Domain_Value_Definition_Source: ESRI GIS software Attribute: Attribute_Label: Area Attribute_Definition: The size of the shape in coverage units. In the distributed file, coverage units represent square decimal degrees. Attribute_Definition_Source: National Atlas of the United States Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.00000 Range_Domain_Maximum: 50.151550 Attribute: Attribute_Label: Perimeter Attribute_Definition: The perimeter of the shape in coverage units. In the distributed file, coverage units represent decimal degrees. Attribute_Definition_Source: National Atlas of the United States Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.00857 Range_Domain_Maximum: 261.67570 Attribute: Attribute_Label: Ecoomrp075 Attribute_Definition: Internal feature number. Attribute_Definition_Source: National Atlas of the United States Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 2 Range_Domain_Maximum: 3076 Attribute: Attribute_Label: Level3 Attribute_Definition: The numeric code of the Level III ecoregion. Attribute_Definition_Source: National Atlas of the United States Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 120 Attribute: Attribute_Label: Level3_name Attribute_Definition: The name of the Level III ecoregion. Attribute_Definition_Source: National Atlas of the United States Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: (see table below) Enumerated_Domain_Value_Definition: A full description of the ecoregions can be found at > Code Name >------------------------------------------------------------------- > 1 Coast Range > 2 Puget Lowland > 3 Willamette Valley > 4 Cascades > 5 Sierra Nevada > 6 Southern and Central California Chaparral and Oak Woodlands > 7 Central California Valley > 8 Southern California Mountains > 9 Eastern Cascades Slopes and Foothills > 10 Columbia Plateau > 11 Blue Mountains > 12 Snake River Plain > 13 Central Basin and Range > 14 Mojave Basin and Range > 15 Northern Rockies > 16 Idaho Batholith > 17 Middle Rockies > 18 Wyoming Basin > 19 Wasatch and Uinta Mountains > 20 Colorado Plateaus > 21 Southern Rockies > 22 Arizona/New Mexico Plateau > 23 Arizona/New Mexico Mountains > 24 Chihuahuan Deserts > 25 High Plains > 26 Southwestern Tablelands > 27 Central Great Plains > 28 Flint Hills > 29 Cross Timbers > 30 Edwards Plateau > 31 Southern Texas Plains > 32 Texas Blackland Prairies > 33 East Central Texas Plains > 34 Western Gulf Coastal Plain > 35 South Central Plains > 36 Ouachita Mountains > 37 Arkansas Valley > 38 Boston Mountains > 39 Ozark Highlands > 40 Central Irregular Plains > 41 Canadian Rockies > 42 Northwestern Glaciated Plains > 43 Northwestern Great Plains > 44 Nebraska Sand Hills > 45 Piedmont > 46 Northern Glaciated Plains > 47 Western Corn Belt Plains > 48 Lake Agassiz Plain > 49 Northern Minnesota Wetlands > 50 Northern Lakes and Forests > 51 North Central Hardwood Forests > 52 Driftless Area > 53 Southeastern Wisconsin Till Plains > 54 Central Corn Belt Plains > 55 Eastern Corn Belt Plains > 56 Southern Michigan/Northern Indiana Drift Plains > 57 Huron/Erie Lake Plains > 58 Northeastern Highlands > 59 Northeastern Coastal Zone > 60 Northern Appalachian Plateau and Uplands > 61 Erie Drift Plain > 62 North Central Appalachians > 63 Middle Atlantic Coastal Plain > 64 Northern Piedmont > 65 Southeastern Plains > 66 Blue Ridge > 67 Ridge and Valley > 68 Southwestern Appalachians > 69 Central Appalachians > 70 Western Allegheny Plateau > 71 Interior Plateau > 72 Interior River Valleys and Hills > 73 Mississippi Alluvial Plain > 74 Mississippi Valley Loess Plains > 75 Southern Coastal Plain > 76 Southern Florida Coastal Plain > 77 North Cascades > 78 Klamath Mountains > 79 Madrean Archipelago > 80 Northern Basin and Range > 81 Sonoran Basin and Range > 82 Laurentian Plains and Hills > 83 Eastern Great Lakes and Hudson Lowlands > 84 Atlantic Coastal Pine Barrens > 101 Arctic Coastal Plain > 102 Arctic Foothills > 103 Brooks Range > 104 Interior Forested Lowlands And Uplands > 105 Interior Highlands > 106 Interior Bottomlands > 107 Yukon Flats > 108 Ogilvie Mountains > 109 Subarctic Coastal Plains > 110 Seward Peninsula > 111 Ahklun And Kilbuck Mountains > 112 Bristol Bay-Nushagak Lowlands > 113 Alaska Peninsula Mountains > 114 Aleutian Islands > 115 Cook Inlet > 116 Alaska Range > 117 Copper Plateau > 119 Pacific Coastal Mountains > 120 Coastal Western Hemlock-Sitka Spruce Forests Enumerated_Domain_Value_Definition_Source: U.S. Environmental Protection Agency Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: Earth Science Information Center, U.S. Geological Survey Contact_Address: Address_Type: Mailing address Address: 507 National Center City: Reston State_or_Province: VA Postal_Code: 20192 Contact_Voice_Telephone: 1-888-ASK-USGS (1-888-275-8747) Contact_Voice_Telephone: 703-648-5920 Contact_Instructions: In addition to the address above there are other ESIC offices throughout the country. A full list of these offices is at . Distribution_Liability: Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made by the U.S. Geological Survey regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty. No responsibility is assumed by the U.S. Geological Survey in the use of these data. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: ESRI Shapefile Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: Digital_Form: Digital_Transfer_Information: Format_Name: SDTS Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: Fees: There is no charge for this map layer. Metadata_Reference_Information: Metadata_Date: 20060419 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Peg Rawson Contact_Organization: National Atlas of the United States Contact_Address: Address_Type: Mailing address Address: 12201 Sunrise Valley Drive Address: MS-561 City: Reston State_or_Province: VA Postal_Code: 20192 Contact_Voice_Telephone: 703-648-4183 Contact_Electronic_Mail_Address: atlasmail@usgs.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Security_Information: Metadata_Security_Classification_System: None Metadata_Security_Classification: Unclassified Metadata_Security_Handling_Description: None