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nv_omer_eco3

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: US Environmental Protection Agency

Publication_Date: 2003

Title: Omernik Ecoregions - Level 3 (nv_omer_eco3)

Geospatial_Data_Presentation_Form: vector digital data

Other_Citation_Details: revision of Omernik 1987

Online_Linkage: N/A

Description:

Abstract:

The ecoregions shown here have been derived from Omernik (1987) and from refinements of Omernik's framework that have been made for other projects. These ongoing or recently completed projects, conducted in collaboration with the U.S. EPA regional offices and with state resource management agencies, involve refining ecoregions, defining subregions, and locating sets of reference sites. Designed to serve as a spatial framework for environmental resource management, ecoregions denote areas within which ecosystems (and the type, quality, and quantity of environmental resources) are generally similar. The most immediate needs are to develop regional biological criteria and water quality standards and to set management goals for nonpoint source pollution.

The approach used to compile this map is based on the premise that ecological regions can be identified through the analysis of the 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 phenomena include geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another regardless of the hierarchical level. Because of possible confusion with other meanings of terms for different levels of ecologic regions, a Roman numeral classification scheme has been adopted for this effort. Level I is the coarsest level, dividing North America into 15 ecological regions whereas at Level II the continent is subdivided into 52 classes. Level III is the hierarchical level shown on this map. For portions of the United States the ecoregions have been further subdivided to level IV. The applications of the ecoregions are explained in Gallant et al. (1989) and in reports and publications from the state and regional projects. For additional information, contact James M. Omernik, U.S. EPA National Health and Environmental Effects Laboratory (NHEERL), 200 SW 35th St., Corvallis, OR 97333 (phone: 541-754-4458).

Purpose:

Assist managers of aquatic and terrestrial resources in understanding the regional patterns of the realistically attainable quality of these resources.

Supplemental_Information:

Procedures_Used: The ecoregion boundaries of Omernik (1987) were originally compiled at a scale of 1:3,168,000 using a variety of scale source maps, and the ecoregion map was published at a display scale of 1:7,500,000. All level IV ecoregion delineations and most all level III revisions are digitized from the U.S.G.S. 1:250,000 base maps. For this coverage, USECO, the revised level III boundaries have been smoothed and generalized appropriately for a 1:7,500,000 display scale. 1) Prior to digitizing, each base map must be initialized to orient the map and relate it in geographic coordinates to the surface of the earth. When the registration tics are entered at the start of digitizing a transformation error of <0.003 must be achieved in order to insure a high level of registration accuracy. The person responsible for digital data entry completes a data sheet describing coverage name, date of entry, and whether a topology for the coverage is established. 2) All level IV ecoregion delineations and most all level III revisions are digitized from the U.S.G.S. 1:250,000 base maps. For this coverage, USECO, the revised level III boundaries have been smoothed and generalized appropriate for a 1:7,500,000 display scale. Prior to digitizing each base map must be initialized to orient the map and relate it in geographic coordinates to the surface of the earth. When the registration tics are entered at the start of digitizing a transformation error of <0.003 must be achieved in order to insure a high level of registration accuracy. The person responsible for digital data entry completes a data sheet describing coverage name, date of entry, and whether a topology for the coverage is established. 3) After each 1:250,000 base map has been digitized, a topology for each coverage is established. This function creates unique identities for each polygon. 4) Next each base map is tested for polygon errors through an internal editing function. Errors are corrected for unlabeled polygons, unclosed polygons, or polygons with more than one label. Topology is reestablished for each coverage and tested again until no error are indicated. 5) The digital coverage is then plotted at the same scale as the original base map. This coverage is overlaid on a light table with the original and visually inspected for replication of original lines with digitized lines. Two individuals independently inspect the coverage for accuracy.

Revisions 1. Original lines digitized 1986? (unknown number of revisions between then and now) 2. Updated lines in Ohio and Indiana 1/96 3. updated lines in Tenn. 2/96 4. updated lines western Oregon and Washington 6/6/96 5. updated lines in ND from updated ND level IV lines 9/96 6. updated lines in SD from updated SD level IV lines 9/96 7. deleted # 41 (became part of #42), added 3 new ecoregions (#41, #79, and #80), extended #61 around adirondacks, #34 was extended south to Mexican boarder. 12/96 8. updated line in SD from revised level IV lines in SD 12/96 9. merged Thompson-Okanaga Highlands ecoregion (79) with Northern Rockies (15). Madrean Archipelago (80) item ECO became 79. 2/97 10. updated line in Ohio, and line in central Oregon from revised lines. 10/97 11. updated lines in Wisconsin from revised level IV lines. 11/97 12. updated lines in Montana from revised level IV lines. 1/98 13. Updated lines to agree with lines from the National Interagency Technical Team (NITT). Areas where lines were altered include Ecoregion 4 in Nothern California, slightly shifted to the west; Ecoregions 36, 37, 38 and 39; ecoregion 73, has a tail going up Red River through Louisiana, into S. Arkansas; ecoregion 12 was split into two, 12 and 80 (Snake River Basin and High Desert); Ecoregion 14 was split into two, 14 and 81; Ecoregion 59 was split in Maine, 59 and 82; ecoregion 61 was split into 61 and 83; ecoregion 63, along the east coast, was split into 63 and 84. 14. Updated lines to agree with level III revisions to AL, GA, and KS. Lines were smoothed using alter and vertex move, add, and delete. Ecoregion names were also updated as follows: region #24 changed from "Southern Deserts" to "Chihuahuan Desert", region #80 changed from "Snake River High Desert" to "Northern Basin and Range", and region #13 changed from "Northern Basin and Range" to "Central Basin and Range". 3/99 15. Updated lines in EPA Region 3 from revised level IV lines. Level III lines were also added to NJ separating 63 and 84. Revisions were made for NE representing level IV updates. 3/99 16. Updated level III lines in UT, NE, KS, MD, GA, SC, and AL according to final and latest draft lines for respective level IV ecoregions. 3/00 17. Updated level III lines in OR, WA, ID, MT, UT, NV, SC, GA, NC, KS, NE, and MO according to lines final and latest draft lines for respective level IV ecoregions smoothed by Jim Omernik. 11/00 18. Updated level III lines according to revisions in OR, NV, ID, MS, LA, AL, SC, NC, KY, AR, and WI. 08/2002 jac 19. Revised level III lines according to updates in Mississippi Alluvial Plain and in WY. 2/2003 jac

Reviews_Applied_to_Data 1. Lines and map were reviewed by ?? 2. Revised lines were reviewed by Alan Woods, Dynamac 3. Revised lines were reviewed by Glenn Griffith, EPA 4. Revised lines were reviewed by David Pater, Dynamac 5. Revised lines were reviewed by Sandy Bryce, Dynamac 6. Revised lines were reviewed by Sandy Bryce, Dynamac 7. Revised lines were reviewed by Jim Omernik, EPA 8. Revised lines were reviewed by Sandy Bryce, Dynamac 9. Revised line was reviewed by Jim Omernik, EPA 10. Revised lines were reviewed by Sandy Bryce, Dynamac 11. Revised lines were reviewed by Shannen Chapman, Dynamac 12. Revised lines were reviewed by Alan Woods, Dynamac 13. Revised lines were reviewed by Jim Omernik, EPA 14. Revised lines were reviewed by Glenn Griffith, NRCS 15. Revised lines were reviewed by Alan Woods, Dynamac 16. Revised lines were reviewed by Alan Woods, Dynamac & Glenn Griffith, NRCS 17. Revised lines were reviewed by Jim Omernik, EPA 18. Revised lines were reviewed by Glenn Griffith, NRCS 19. Revisions were reviewed by Shannen Chapman, Glenn Griffith and Jim Omernik

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 1986

Ending_Date: 2/03

Currentness_Reference: ground condition

Status:

Progress: 2003

Maintenance_and_Update_Frequency: None planned

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -123.097015

East_Bounding_Coordinate: -104.247632

North_Bounding_Coordinate: 45.924460

South_Bounding_Coordinate: 31.582606

Keywords:

Theme:

Theme_Keyword_Thesaurus: None

Theme_Keyword: Level III ecoregions

Place:

Place_Keyword_Thesaurus: None

Place_Keyword: Ecoregions of Continental US

Stratum:

Stratum_Keyword_Thesaurus: None

Temporal:

Temporal_Keyword_Thesaurus: None

Access_Constraints: n/a

Access_Constraints: n/a

Use_Constraints: for use at 1:250,000 or smaller scales

Point_of_Contact:

Native_Data_Set_Environment:

Microsoft Windows 2000 Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 8.2.0.700

Cross_Reference:

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report: See Entity_Attribute_Information

Logical_Consistency_Report: Polygon and chain-node topology present.

Completeness_Report:

Positional_Accuracy Horizontal_Positional_Accuracy Vertical_Positional_Accuracy Vertical_Positional_Accuracy_Report

Lineage:

Process_Step:

Process_Description: Metadata imported.

Source_Used_Citation_Abbreviation: C:\WINDOWS\tmp\xmlB.tmp

Process_Step:

Process_Description: Metadata imported.

Source_Used_Citation_Abbreviation: D:\NevadaDataBrowser\ecoregion_bnd\nv_omer_eco\metadata.xml

Process_Step:

Process_Description: Metadata imported.

Source_Used_Citation_Abbreviation:

D:\NevadaDataBrowser\downloads\ecoregion_bnd\nv_omer_eco3.shp.xml

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Vector

Point_and_Vector_Object_Information:

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: Complete chain

Point_and_Vector_Object_Count: 56

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: Label point

Point_and_Vector_Object_Count: 5

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains

Point_and_Vector_Object_Count: 10

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: Point

Point_and_Vector_Object_Count: 4

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: 0.002048

Ordinate_Resolution: 0.002048

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:

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Detailed_Description:

Entity_Type:

Entity_Type_Label: nv_omer_eco3.pat

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: AREA

Attribute_Definition: Area of feature in internal units squared.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain: Positive real numbers that are automatically generated.

Attribute:

Attribute_Label: PERIMETER

Attribute_Definition: Perimeter of feature in internal units.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain: Positive real numbers that are automatically generated.

Attribute:

Attribute_Label: NV_OMER_ECO3#

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: NV_OMER_ECO3-ID

Attribute_Definition: User-defined feature number.

Attribute_Definition_Source: ESRI

Attribute:

Attribute_Label: OMER_ALB_

Attribute:

Attribute_Label: OMER_ALB_I

Attribute:

Attribute_Label: ECO

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition_Source:

ECO Ecoregion 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 S. Michigan/N. Indiana Drift Plains 57 Huron/Erie Lake Plains 58 Northeastern Highlands 59 Northeastern Coastal Zone 60 Northern Appalachian Plateau and Uplands 61 Erie Drift Plains 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

Attribute:

Attribute_Label: LEVEL3

Attribute:

Attribute_Label: LEVEL3_NAM

<< Back To Map

Distribution_Information:

Resource_Description: Downloadable Data

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Transfer_Size: 0.306

Metadata_Reference_Information:

Metadata_Date: 20050418

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization:

REQUIRED: The organization responsible for the metadata information.

Contact_Person: REQUIRED: The person responsible for the metadata information.

Contact_Address:

Address_Type:

REQUIRED: The mailing and/or physical address for the organization or individual.

City: REQUIRED: The city of the address.

State_or_Province: REQUIRED: The state or province of the address.

Postal_Code: REQUIRED: The ZIP or other postal code of the address.

Contact_Voice_Telephone:

REQUIRED: The telephone number by which individuals can speak to the organization or individual.

Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Time_Convention: local time

Metadata_Extensions:

Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>

Profile_Name: ESRI Metadata Profile