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Ligue des Bibliothèques Europeénnes de Recherche, Groupe des Cartothécaires de LIBER
Edited description derived from http:/www.blm.gov/gis/nsdi.htm.
Metadata for ECOREGION
USGS Node of National Geospatial Data Clearinghouse
Last modified: 94-12-30.10:57:49.Fri
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1. Identification Information (includes fields 8, 9 and 10):
Citation Information:
Originator: Omernick, J. M.
Publication Date: 1987
Title: Aquatic ecoregions of the conterminous United States
Type of Map: map
Publication Information:
Publication Place:
Publisher: USEPA
Description:
EPA Ecoregion Map
Abstract:
Ecoregions are based on perceived patterns of a combination of causal and integrative factors including land use, land surface form, potential natural vegetation, and soils (Omernik, 1987). This is a copy of the ecoregion coverage of Omernik (1987) with some item names modified.
Purpose:
This coverage is intended for national-level studies of water resources.
Supplemental Information:
Limitations of Data:
Procedures:
The coverage was installed from an ARC/INFO.ARCE file supplied by EPA Corvallis. Some item names were modified and others were redefined to make the coverage more convenient to use and to conform to more conventional item names.
Reviews Applied:
The ecoregions were plotted on a terminal to ensure the .ARCE file was imported properly. No claims are made regarding the accuracy of the original data or linework.
Other Related Data Sets:
References Cited:
Omernik, J. M., 1987. Aquatic ecoregions of the conterminous United States. Annals of the Association of American Geographers, 77:118-125 (map scale 1:7,500,000).
Notes:
Other:
Time Period of Content:
Time Period Information:
Single Date/Time:
Calendar Date: 12/17/91
Currentness Reference: publication date
Status:
Progress: Open distribution. Data have been published by others.
Maintenance and Update Frequency: As needed
Spatial Domain:
Bounding Coordinates:
West Bounding Coordinate: -125.0000
East Bounding Coordinate: -66.0000
North Bounding Coordinate: 50.0000
South Bounding Coordinate: 24.0000
Keywords:
Theme:
Theme Keyword Thesaurus: None
Theme Keyword: Ecoregion
Access Constraints:
None
Use Constraints:
None
Point of Contact:
Security Information:
Security Classification: UNCLASSIFIED
Native Data Set Environment:
Arc/INFO
2. Data Quality Information:
Logical Consistency Report:
Polygon topology present.
Completeness Report:
(See Supplemental Information)
Positional Accuracy:
Horizontal Positional Accuracy: See Supplemental Information)
Vertical Positional Accuracy: See Supplemental Information)
Lineage:
See Supplemental Information for overview.
Process Step:
Process Description:
Rev. 1.0 Installed from.ARCE tape.
Process Date: 09/28/91
Process Step:
Process Description:
Rev. 1.1 Converted to Data General workstation.
Item redefinitions revised and documentation added.
Process Date: 12/17/91
3. Spatial Data Organization Information:
Direct Spatial Reference Method:
Vector
Point and Vector Object Information:
SDTS Terms Description:
SDTS Point and Vector Object Type: Point
Point and Vector Object Count: 3732
SDTS Point and Vector Object Type: String
Point and Vector Object Count: 8064
SDTS Point and Vector Object Type: GT-polygon composed of chains
Point and Vector Object Count: 3733
4. Spatial Reference Information:
Horizontal Coordinate System Definition:
Planar:
Map Projection:
Map Projection Name: Albers Conical Equal Area
Alber Conical Equal Area:
Standard Parallel: 29.5
Standard Parallel: 45.5
Longitude of Central Meridian: -96
Latitude of Projection Origin: 23
False Easting: 0.0
False Northing: 0.0
5. Entity and Attribute Information:
Detailed Description:
Entity Type:
Entity Type label: ECOREGION.PAT
Entity Type Definition: Polygon attribute table
Number of Attributes in Entity: 11
Attribute:
Attribute Label: AREA
Attribute Definition: Area of polygon in square coverage units
Attribute Definition Source: Computed
Attribute Domain Values: Positive real numbers
Attribute:
Attribute Label: PERIMETER
Attribute Definition: Perimeter of polygon in coverage units
Attribute Definition Source: Computed
Attribute Domain Values: Positive real numbers
Attribute:
Attribute Label: ECOREGION#
Attribute Definition: Internal feature number
Attribute Definition Source: Computed
Attribute Domain Values: Sequential unique positive integer
Attribute:
Attribute Label: ECOREGION-ID
Attribute Definition: User-assigned feature number
Attribute Definition Source: User-defined
Attribute Domain Values: Integer
Attribute:
Attribute Label: ECO
Attribute Definition: Full ecoregion code
Attribute Definition Source: Omernik (1987)
Attribute Domain Values: positive numbers are ecoregions
Attribute:
Attribute Label: PBMIN1
Attribute Definition: State code item used by EPA
Attribute Definition Source: Omernik (1987)
Attribute Domain Values: (FIPS)
Attribute:
Attribute Label: LWCODE
Attribute Definition: Land/water code.
Attribute Definition Source: Omernik (1987)
Attribute Domain Values: L=land, W=water, ZZ=missing
Attribute:
Attribute Label: COLOR
Attribute Definition: Working item for plotting
Attribute Definition Source: Local
Attribute Domain Values: numeric
Attribute:
Attribute Label: ECOREGION
Attribute Definition: Ecoregion code
Attribute Definition Source: Omernik (1987)
Attribute Domain Values: 1-76, -1=none
Attribute:
Attribute Label: TYPICAL
Attribute Definition: Indicates strength of association in ecoregion
Attribute Definition Source: Omernik (1987)
Attribute Domain Values: 0=most typical, 1=generally typical
Attribute:
Attribute Label: FIPSST
Attribute Definition: State code
Attribute Definition Source: Omernik (1987)
Attribute Domain Values: (FIPS)
Overview Description:
Entity and Attribute Overview:
Ecoregions are based on perceived patterns of a combination of causal and integrative factors including land use, land surface form, potential natural vegetation, and soils (Omernik, 1987). There are 76 ecoregions, identified by the item ECOREGION.
The item TYPICAL allows a fuzzy logic whereby polygons identified with TYPICAL = 0 are "most typical" of the ecoregion they represent. Those identified by TYPICAL = 1 are "generally typical" any may not have all the characteristics.
The ecoregion coverage is superimposed upon a coverage of states. The state lines may divide polygons.
Entity and Attribute Detail Citation: See Entity and Attribute Information )
6. Distribution Information:
Distributor Contact Organization: U.S. Geological Survey
Distributor Contact Address: (Please use electronic mail.)
Distributor Contact Voice Telephone: Please use electronic mail.
Distributor Contact Electronic Mail Address: lanfear@usgs.gov
Resource Description: ECOREGION
Distribution Liability:
Although these data have been processed successfully on a computer system at the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the Geological Survey regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty.
Standard Order Process:
Digital Form:
Digital Transfer Information:
Format Name: SDTS and ARCE
Files are compressed with the GNU-zip public-domain file compression utility.
Digital Transfer Option:
ECOREGION is available via Internet!
Select the "Load to Local Disk" option on your client software and choose one of these formats:
SDTS
Arc/INFO Export
Fees: None.
Available Time Period: Immediate.
7. Metadata Reference Information:
Metadata Date: 19941230
Metadata Contact: lanfear
Metadata Standard Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata Standard Version: 19940608
Metadata Time Convention: Local Time
© Federal Geographic Data Committee (FGDC, USA)