Ecoregions by EPA region 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
Citation
Title Level III Ecoregions of EPA Region 3
publication Date
2010-05-01
presentationForm
mapDigital
Series
Name
Issue
cited responsible party
-
publisher
organisation Name
U.S. EPA Office of Research & Development (ORD) - National Health and Environmental Effects Research Laboratory (NHEERL)
Contact information
Address
, Corvallis, OR
cited responsible party
-
originator
organisation Name
U.S. Environmental Protection Agency
US Ecoregion Levels III and IV, North American (CEC) Ecoregion Levels I, II, III
thesaurus name >
Title User
Location keywords:
Delaware
Maryland
Pennsylvania
United States
Virginia
Washington DC
West Virginia
thesaurus name >
Title None
purpose:
Ecoregion maps assist managers of aquatic and terrestrial resources to understand the regional patterns of the realistically
attainable quality of these resources
Resource language:
eng; USA
Resource progress code:
ONGOING
Resource Maintenance Information
maintenance or update frequency:
asNeeded
Constraints on resource usage:
Constraints
Use limitation statement:
https://edg.epa.gov/EPA_Data_License.htm
Constraints on resource usage:
Legal Constraints
use constraint:
otherRestrictions
Other constraints
Use Constraints: None
Constraints on resource usage:
Legal Constraints
Access Constraints
otherRestrictions
Other constraints
Access Constraints: None
Constraints on resource usage:
Security Constraints
Classification
NO CONFIDENTIALITY
Classification
System FIPS Pub 199
Handling
Description Standard Technical Controls
Spatial representation type code:
vector
Processing environment:
Native Dataset Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 9.3.1.3000
Resource extent
Geographic Extent
Geographic Bounding Box
westBoundLongitude
-83.675409
eastBoundLongitude
-74.030504
northBoundLatitude
42.950804
southBoundLatitude
35.525667
Temporal Extent
2010-05-01
Additional information on resource:
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.
point of contact
-
pointOfContact
individual Name Marc Weber
organisation Name
U.S. Environmental Protection Agency, Office of Research & Development (ORD) - National Health and Environmental Effects Research
Laboratory (NHEERL)
source description
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.Source Type
Resource extent
AbsoluteExternalPositionalAccuracy
name Of Measure Horizontal Positional Accuracy Report
evaluation Method Description
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)
Completeness Commission
evaluation Method Description
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.
Completeness Omission
evaluation Method Description
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.
ConceptualConsistency
measure Description
Although ecoregion polygons and attributes have been checked for accuracy, some errors may remain. Polygons along state borders
were reviewed and updated, May 2010.
organisation Name
U.S. Environmental Protection Agency, Office of Research & Development (ORD) - National Health and Environmental Effects Research
Laboratory (NHEERL)
notes: This metadata was automatically generated from the FGDC Content Standards for Digital Geospatial Metadata standard (version
FGDC-STD-001-1998) using the 2012-06-20T17:21:00 version of the FGDC RSE to ISO 19115-2 transform.
Metadata contact
-
pointOfContact
individual Name Colleen Burch Johnson
organisation Name
SRA / Raytheon Contractors to US EPA