Level IV Ecoregions of Arkansas

Metadata also available as

Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator: US Environmental Protection Agency
Publication_Date: 20100501
Title: Level IV Ecoregions of Arkansas
Geospatial_Data_Presentation_Form: vector digital data
Series_Information:
Publication_Information:
Publication_Place: Corvallis, OR
Publisher:
U.S. EPA Office of Research & Development (ORD) - National Health and Environmental Effects Research Laboratory (NHEERL)
Online_Linkage: <ftp://ftp.epa.gov/wed/ecoregions/ar/ar_eco_l4.zip>
Online_Linkage: <http://www.epa.gov/wed/pages/ecoregions.htm>
Larger_Work_Citation:
Citation_Information:
Publication_Date:
Title:
Series_Information:
Publication_Information:
Description:
Abstract:
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, 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, Dynamac Corporation, 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
Purpose:
Ecoregion maps assist managers of aquatic and terrestrial resources to understand the regional patterns of the realistically attainable quality of these resources
Supplemental_Information:
Electronic versions of ecoregion maps and posters, as well as other ecoregion resources are available at: <http://www.epa.gov/wed/pages/ecoregions.htm>. Symbology layers for US Levels III and IV also available. Level IV ecoregions are not complete for California and Arizona, as of May, 2010. For these states, the polygons are for Level III or lower. The field "US_L4CODE" contains placeholder information derived from "US_L3CODE". Ecoregions were digitized at 1:250,000 scale and are intended for large geographic extents (i.e. states, multiple counties, or river basins). Use for smaller areas, such as individual counties or a 1:24,000 scale map boundary, is not recommended.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20100501
Currentness_Reference: Publication date
Status:
Progress: Ongoing
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -94.678738
East_Bounding_Coordinate: -89.597087
North_Bounding_Coordinate: 36.632464
South_Bounding_Coordinate: 32.872256
Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: biota
Theme_Keyword: boundaries
Theme_Keyword: environment
Theme_Keyword: location
Theme:
Theme_Keyword_Thesaurus: EPA GIS Keyword Thesaurus
Theme_Keyword: Biology
Theme_Keyword: Conservation
Theme_Keyword: Ecology
Theme_Keyword: Ecosystem
Theme_Keyword: Environment
Theme_Keyword: Land
Theme_Keyword: Natural Resources
Theme:
Theme_Keyword_Thesaurus: User
Theme_Keyword:
US Ecoregion Levels III and IV, North American (CEC) Ecoregion Levels I, II, III
Place:
Place_Keyword: Selected State, Conterminous United States
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: Arkansas
Place_Keyword: United States
Access_Constraints: None
Use_Constraints: None
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Marc Weber
Contact_Organization:
U.S. Environmental Protection Agency, Office of Research & Development (ORD) - National Health and Environmental Effects Research Laboratory (NHEERL)
Contact_Position: GIS Analyst
Contact_Address:
Address_Type: mailing and physical address
Address: 200 S.W. 35th St.
City: Corvallis
State_or_Province: OR
Postal_Code: 97333
Contact_Voice_Telephone: (541) 754-4469
Contact_Electronic_Mail_Address: weber.marc@epa.gov
Contact_Instructions: <http://www.epa.gov/>
Security_Information:
Security_Classification_System: FIPS Pub 199
Security_Classification: No Confidentiality
Security_Handling_Description: Standard Technical Controls
Native_Data_Set_Environment:
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 9.3.1.3000
Cross_Reference:
Citation_Information:
Title: Ecoregions of the United States

Data_Quality_Information:
Logical_Consistency_Report:
Although ecoregion polygons and attributes have been checked for accuracy, some errors may remain. Polygons along state borders were reviewed and updated, May 2010.
Completeness_Report:
Level IV ecoregions are not complete for California and Arizona, as of May, 2010. For these states, the polygons are for Level III or lower. The field 'US_L4CODE" contains placeholder information derived from "US_L3CODE". Ecoregions were digitized at 1:250,000 scale and are intended for large geographic extents (i.e. states, multiple counties, or river basins). Use for smaller areas, such as individual counties or a 1:24,000 scale map boundary, is not recommended.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Data were collected using methods that have unknown accuracy (EPA National Geospatial Data Policy [NGDP] Accuracy Tier 10). For more information, please see EPA's NGDP at <http://epa.gov/geospatial/policies.html>)
Lineage:
Source_Information:
Source_Contribution:
The state borders were derived from the dtl_st.sdc on the ArcGIS DVD provided by ESRI. It was modified by removing Alaska and Hawaii polygons and all but the State field, adding some coastal islands based on imagery or NHDPlus areas, and restoring topology (removing internal gaps and small overlaps). The EPA regions were added to this custom geodatabase (dtl_48plyf) prior to the intersection process with the seamless ecoregion data.
Process_Step:
Process_Description:
1) U.S.G.S. 1:250,000 topographic maps are used to delineate the ecoregions. The lines drawn are manually digitized or scanned to produce georeferenced electronic files. 2) All base maps are joined together and errors along the edges are resolved. 3) Topology is established and the maps are reviewed for accuracy, completeness, and conformity with the original lines. Corrections are made as needed and topology regenerated. 4) Attributes are added. 5) Maps are plotted for visual inspection by two individuals and necessary changes made. 6) Ecoregions from all available states are merged and dissolved to identify and correct inconsistencies. 7) Polygons of the corrected seamless ecoregion features are extended beyond the coastal borders. 8) State and Ecoregion datasets are intersected. 9) Topology errors removed. 10) Final QA
Process_Date: 20100526

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: G-polygon
Point_and_Vector_Object_Count: 134

Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Albers Conical Equal Area
Albers_Conical_Equal_Area:
Standard_Parallel: 29.500000
Standard_Parallel: 45.500000
Longitude_of_Central_Meridian: -96.000000
Latitude_of_Projection_Origin: 23.000000
False_Easting: 0.000000
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.000001
Ordinate_Resolution: 0.000001
Planar_Distance_Units: meters
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222

Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: ar_eco_l4
Attribute:
Attribute_Label: FID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: Shape
Attribute_Definition: Feature geometry.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: OBJECTID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: US_L4CODE
Attribute_Definition: Code for Level IV Ecoregion (US)
Attribute_Definition_Source: USEPA
Attribute:
Attribute_Label: US_L4NAME
Attribute_Definition: Name for Level IV Ecoregion (US)
Attribute_Definition_Source: USEPA
Attribute:
Attribute_Label: US_L3CODE
Attribute_Definition: Code for Level III Ecoregion (US)
Attribute_Definition_Source: USEPA
Attribute:
Attribute_Label: US_L3NAME
Attribute_Definition: Name for Level III Ecoregion (US)
Attribute_Definition_Source: USEPA
Attribute:
Attribute_Label: NA_L3CODE
Attribute_Definition: Code for Level III Ecoregion (North America)
Attribute_Definition_Source: CEC
Attribute:
Attribute_Label: NA_L3NAME
Attribute_Definition: Name for Level III Ecoregion (North America)
Attribute_Definition_Source: CEC
Attribute:
Attribute_Label: NA_L2CODE
Attribute_Definition: Code for Level II Ecoregion (North America)
Attribute_Definition_Source: CEC
Attribute:
Attribute_Label: NA_L2NAME
Attribute_Definition: Name for Level II Ecoregion (North America)
Attribute_Definition_Source: CEC
Attribute:
Attribute_Label: NA_L1CODE
Attribute_Definition: Code for Level I Ecoregion (North America)
Attribute_Definition_Source: CEC
Attribute:
Attribute_Label: NA_L1NAME
Attribute_Definition: Name for Level I Ecoregion (North America)
Attribute_Definition_Source: CEC
Attribute:
Attribute_Label: STATE_NAME
Attribute_Definition: Name of State (US)
Attribute:
Attribute_Label: EPA_REGION
Attribute_Definition: EPA Administrative Region
Attribute:
Attribute_Label: Shape_Leng
Attribute_Definition: Length of feature in internal units
Attribute_Definition_Source: ESRI Positive real numbers that are automatically generated.
Attribute:
Attribute_Label: Shape_Area
Attribute_Definition: Area of feature in internal units squared.
Attribute_Definition_Source: ESRI Positive real numbers that are automatically generated.
Attribute_Domain_Values:
Unrepresentable_Domain: Positive real numbers that are automatically generated.
Attribute:
Attribute_Label: L4_KEY
Attribute_Definition: US Level IV Code and Name for Legend, Match to Style
Attribute:
Attribute_Label: L3_KEY
Attribute_Definition: US Level III Code and Name for Legend, Match to Style
Attribute:
Attribute_Label: L2_KEY
Attribute_Definition: NA Level II Code and Name for Legend, Match to Style
Attribute:
Attribute_Label: L1_KEY
Attribute_Definition: NA Level I Code and Name for Legend, Match to Style

Metadata_Reference_Information:
Metadata_Date: 20110310
Metadata_Future_Review_Date: 20140920
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Colleen Burch Johnson
Contact_Organization: SRA / Raytheon Contractors to US EPA
Contact_Position: GIS Analyst
Contact_Address:
Address_Type: mailing and physical address
Address: 200 S.W. 35th St
City: Corvallis
State_or_Province: OR
Postal_Code: 97333
Contact_Voice_Telephone: (541) 754-4454
Contact_Electronic_Mail_Address: johnson.colleen@epa.gov
Contact_Instructions: <http://www.epa.gov/>
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time

Generated by mp version 2.9.6 on Thu Mar 10 15:37:27 2011