National Land Cover Database Zone 12 Land Cover Layer

Metadata also available as

Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator: U.S. Geological Survey
Publication_Date: 20030901
Title: National Land Cover Database Zone 12 Land Cover Layer
Edition: 1.0
Geospatial_Data_Presentation_Form: remote-sensing image
Series_Information:
Series_Name: None
Issue_Identification: None
Publication_Information:
Publication_Place: Sioux Falls, SD
Publisher: U.S. Geological Survey
Other_Citation_Details:
References: Homer, C., C. Huang, L. Yang, B. Wylie and M. Coan, 2004. Development of a 2001 national land cover database for the United States. Photogrammetric Engineering and Remote Sensing Vol.70,No.7,pp 829-840 or online at www.mrlc.gov/publications. The USGS acknowledges the support of Geomatics Team in development of data in this zone.
Online_Linkage: <http://www.mrlc.gov>
Description:
Abstract:
The National Land Cover Database 2001 land cover layer for mapping zone 12 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of federal agencies (www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (EPA), the U.S. Department of Agriculture (USDA), the U.S. Forest Service (USFS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (FWS), the Bureau of Land Management (BLM) and the USDA Natural Resources Conservation Service (NRCS). One of the primary goals of the project is to generate a current, consistent, seamless, and accurate National Land cover Database (NLCD) circa 2001 for the United States at medium spatial resolution. This landcover map and all documents pertaining to it are considered "provisional" until a formal accuracy assessment can be conducted. For a detailed definition and discussion on MRLC and the NLCD 2001 products, refer to Homer et al. (2004) and <http://www.mrlc.gov/mrlc2k.asp>.

The NLCD 2001 is created by partitioning the U.S. into mapping zones. A total of 66 mapping zones were delineated within the conterminous U.S. based on ecoregion and geographical characteristics, edge matching features and the size requirement of Landsat mosaics. Mapping zone 12 encompasses whole or portions of several states, including the states of Nevada and California. Questions about the NLCD mapping zone 12 can be directed to the NLCD 2001 land cover mapping team at the USGS/EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov.

Purpose:
The goal of this project is to provide the Nation with complete, current and consistent public domain information on its land use and land cover.
Supplemental_Information:
Corner Coordinates (center of pixel, projection meters) Upper Left Corner: -2051160 meters(X), 2315670 meters(Y) Lower Right Corner: -1557810 meters(X), 1721100 meters(Y)
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19990630
Ending_Date: 20030408
Currentness_Reference: ground condition
Status:
Progress: In work
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -121.009858
East_Bounding_Coordinate: -113.825176
North_Bounding_Coordinate: 42.420025
South_Bounding_Coordinate: 36.267336
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Land Cover
Theme_Keyword: GIS
Theme_Keyword: U.S. Geological Survey
Theme_Keyword: USGS
Theme_Keyword: digital spatial data
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Category
Theme_Keyword: imagery
Theme_Keyword: Base Maps
Theme_Keyword: Earth Cover
Place:
Place_Keyword_Thesaurus:
U.S. Department of Commerce, 1995, Countries, dependencies, areas of special sovereignty, and their principal administrative divisions, Federal Information Processing Standard 10-4,): Washington, D.C., National Institute of Standards and Technology
Place_Keyword: United States
Place_Keyword: U.S.
Place_Keyword: US
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: zone 12
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 (Federal Information Processing Standard 5-2): Washington, D.C., National Institute of Standards and Technology
Place_Keyword: CA
Place_Keyword: California
Place_Keyword: NV
Place_Keyword: Nevada
Access_Constraints: None
Use_Constraints: None
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Position: Customer Services Representative
Contact_Address:
Address_Type: mailing and physical address
Address: USGS/EROS
Address: 47914 252nd Street
City: Sioux Falls
State_or_Province: SD
Postal_Code: 57198-0001
Country: USA
Contact_Voice_Telephone: 605/594-6151
Contact_TDD/TTY_Telephone: 605/594-6933
Contact_Facsimile_Telephone: 605/594-6589
Contact_Electronic_Mail_Address: custserv@usgs.gov
Hours_of_Service: 0800 - 1600 CT, M - F (-6h CST/-5h CDT GMT)
Contact_Instructions:
The USGS point of contact is for questions relating to the data display and download from this web site. For questions regarding data content and quality, refer to: <http://www.mrlc.gov/mrlc2k.asp> or email: mrlc@usgs.gov
Data_Set_Credit: U.S. Geological Survey, SW Regional GAP
Security_Information:
Security_Classification_System: None
Security_Classification: Unclassified
Security_Handling_Description: N/A
Native_Data_Set_Environment:
Microsoft Windows 2000 Version 5.1 (Build 2600) Service Pack 1; ESRI ArcCatalog 9.0.0.535
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
The information on data quality for mapping zone 12 was generated by the Decision Tree algorithm that conducts a cross-validation for assessing classification and prediction reliability. No formal independent accuracy assessment of mapping zone 12 land cover has been made. The regression tree algorithm employed in NLCD 2001 mapping offers a cross-validation option for assessing classification and prediction reliability. Cross-validation can provide relatively reliable estimates for land cover predictions if the reference data used for cross-validation are collected based on a statistically valid sampling design. For mapping zone 12 land cover modeling, a 5-fold cross-validation was conducted by dividing the entire training data set into 5 subsets of equal size. For each model run, an accuracy estimate was derived using one subset to evaluate the model prediction (with the model developed using the remaining training samples). This process was repeated 5 times. After all 5 runs, an average value of all accuracy estimates from the 5 runs were computed. Users should be cautioned that these cross-validation results provide users with only first-order estimates of data quality, and should not be considered a formal accuracy assessment. This landcover map and all documents pertaining to it are considered "provisional " until a formal accuracy assessment can be conducted.
Quantitative_Attribute_Accuracy_Assessment:
Attribute_Accuracy_Value: 84.22 (Single tree validation based on cross validation output)
Attribute_Accuracy_Explanation:
The above listed value is the overall accuracy obtained for the land cover data using a cross-validation estimate from the decision tree model. This document and the described landcover map are considered "provisional" until a formal accuracy assessment is completed. The U.S. Geological Survey can make no guarantee as to the accuracy or completeness of this information, and it is provided with the understanding that it is not guaranteed to be correct or complete. Conclusions drawn from this information are the responsibility of the user.
Logical_Consistency_Report:
The NLCD 2001 database for mapping zone 12 consists of three main data products including: (1) per pixel classified land-cover data (2) sub-pixel percent imperviousness and (3) sub-pixel percent tree canopy density. The land-cover database also includes three additional metadata layers that provide users a spatial node map of the land cover classification. The three layers are: (a) a spatial node map of the land cover classification, (b) a spatial confidence map of the land cover classification, and, (c) a text file of logical statements related to the land cover classification.

Conceptually, the descriptive tree is a classification tree generated by using the final minimum-map-unit land cover product (1 acre) as training data, and Landsat and other ancillary data as predictors. The goal of the descriptive tree is to summarize the effects of boosted trees (10 sequential classification trees) into a single condensed decision tree that can be used as a diagnostic tool for the classification process. This descriptive tree can be used to assess the relative importance of each of the input data sets on each land cover class. Such information may also be useful to customize the minimum-mapping-unit classification to meet a user's specific needs through raster modeling. Descriptive trees usually capture 60 to 80% of the information from the original land cover data.

The leaf or terminal nodes of the descriptive tree are assigned to sequential numbers (called node numbers) and mapped across the entire mapping zone on a pixel-by-pixel basis. These node numbers can then be matched with the various conditional statements associated with each respective terminal node. This spatial layer appears similar to a cluster map, but is the result of a supervised classification - not an unsupervised clustering. This node map can potentially be used as input by users to customize NLCD land cover, by linking the spatial extent of an individual node with the rules of the conditional statement.

The Land Cover spatial classification confidence data layer is provided to users to help determine the per-pixel spatial confidence of the NLCD 2001 land cover prediction from the descriptive tree. The C5 algorithm produces an estimate (a value between 0% and 100%) that indicates the confidence of rule predictions at each node based on the training data. This spatial confidence map should be considered as only one indicator of relative reliability of the land cover classification, rather than a precise estimate. Users should be aware that this estimate is made based on only training data, and is derived from a generalized descriptive decision tree that reproduces the final land cover data. However, this layer provides valuable insight for a user to determine the risk or confidence they choose to place in each pixel of land cover.

A logic statement from a descriptive tree classification describes each classification rule for each classified pixel. An example of the logic statement follows:

IF tasseled-cap wetness > 140 and imperviousness = 0 and canopy density < 4, then classify as Water

This logic file can be used in combination with the spatial node map to identify classification logic and allow modifications of the classification based on user's knowledge and/or additional data sets.

Additional information may be found at <http://www.mrlc.gov/mrlc2k_nlcd.asp>.

Completeness_Report:
This NLCD product of mapping zone 12 Land Cover layer is the version dated February 27, 2006.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report: N/A
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report: N/A
Lineage:
Process_Step:
Process_Description:
The land cover classification was achieved by use of a classification and decision tree method (DT) using a combination of Landsat imagery and ancillary data. The specific DT program employed is called C5, which implements a gain ratio criterion in tree development and pruning (Quinlan, 1993). C5 also implemented several advanced features that can aid and improve land cover classification, including boosting and cross-validation. Boosting is a technique for improving classification accuracy, while cross-validation can provide certain level of estimation regarding the land cover classification quality. In addition, C5 can generate a confidence estimate for each classified pixel and record the associated classification logic in a text file that can be readily interpreted and incorporated into a metadata system.

To conduct the land cover classification using DT, a large quantity of training data is required. For mapping zone 12, training data were collected from several combined sources including South West Regional GAP Landcover training dataset. Training points were collected from a common area map, which represents intersect of SWGAP landcover, MRLC 92 landcover and Utah-Nevada landcover developed by Collin Homer.

Note that the training data were used to map all land cover classes except for four classes in urban and sub-urban areas (developed open space, low intensity developed, medium intensity developed, high intensity developed). All urban and suburban land cover classes were mapped and quality assessed separately through a sub-pixel quantification of impervious surfaces using a regression tree modeling method.

Following the development of the best classification through decision tree modeling, additional steps were required to complete the final land cover product. The four classes in urban and suburban areas were determined from the percent imperviousness mapping product (described in the next section). The threshold for the four classes is: (1) developed open space (imperviousness < 20%), (2) low-intensity developed (imperviousness from 20 - 49%), (3) medium intensity developed (imperviousness from 50 -79%), and (4) high-intensity developed (imperviousness > 79%). Other classes of forest and non-forest were combined with the urban classes to complete the land cover product. Finally visual inspection of the classification was made with areas/pixels that were wrongly classified delineated first as an "area of interest" (AOI), subsequently then limited manual editing was done to eliminate the classification error within the AOI.

The completed single pixel product was then generalized to a 1 acre (approximately 5 ETM+ 30 m pixel patch) minimum mapping unit product using a "smart eliminate" algorithm. This aggregation program subsumes pixels from the single pixel level to a 5-pixel patch using a queens algorithm at doubling intervals. The algorithm consults a weighting matrix to guide merging of cover types by similarity, resulting in a product that preserves land cover logic as much as possible. Acquisition dates of Landsat ETM+ (TM) scenes used for land cover classification in zone 12 are as follows:
SPRING-
Index 1 for Path 39/Row 34 on 05/03/00 = Scene_ID 7039034000012450
Index 2 for Path 40/Row 31 on 04/08/00 = Scene_ID 7040031000009950
Index 2 for Path 40/Row 32 on 04/08/00 = Scene_ID 7040032000009950
Index 3 for Path 40/Row 33 on 04/24/00 = Scene_ID 7040033000011550
Index 2 for Path 40/Row 31 on 04/08/00 = Scene_ID 7040031000009950
Index 4 for Path 41/Row 31 on 05/04/01 = Scene_ID 7041031000112450
Index 4 for Path 41/Row 32 on 05/04/01 = Scene_ID 7041032000112450
Index 4 for Path 41/Row 33 on 05/04/01 = Scene_ID 7041033000112450
Index 5 for Path 41/Row 34 on 04/08/03 = Scene_ID 7041034000309850
Index 6 for Path 42/Row 31 on 05/11/01 = Scene_ID 7042031000113150
Index 7 for Path 42/Row 32 on 03/21/00 = Scene_ID 7042032000008150
Index 8 for Path 42/Row 33 on 04/06/00 = Scene_ID 7042033000009750
Index 8 for Path 42/Row 34 on 04/06/00 = Scene_ID 7042034000009750
Index 9 for Path 43/Row 31 on 04/29/00 = Scene_ID 7043031000012050
Index 9 for Path 43/Row 32 on 04/29/00 = Scene_ID 7043032000012050
Index10 for Path 43/Row 33 on 05/31/00 = Scene_ID 7043033000015250
Index11 for Path 44/Row 32 on 05/12/02 = Scene_ID 7044032000213250
LEAF ON (Summer)-
Index 1 for Path 39/Row 34 on 05/03/00 = Scene_ID 7039034000012450
Index 2 for Path 40/Row 31 on 07/13/00 = Scene_ID 7040031000019550
Index 2 for Path 40/Row 32 on 07/13/00 = Scene_ID 7040032000019550
Index 3 for Path 40/Row 33 on 08/14/00 = Scene_ID 7040033000022750
Index 4 for Path 40/Row 34 on 06/11/00 = Scene_ID 7040034000016350
Index 5 for Path 41/Row 31 on 07/10/02 = Scene_ID 7041031000219150
Index 6 for Path 41/Row 32 on 07/20/00 = Scene_ID 7041032000020250
Index 7 for Path 41/Row 33 on 07/20/00 = Scene_ID 7041033000020250
Index 7 for Path 41/Row 34 on 07/20/00 = Scene_ID 7041034000020250
Index 8 for Path 42/Row 31 on 07/27/00 = Scene_ID 7042031000020950
Index 8 for Path 42/Row 32 on 07/27/00 = Scene_ID 7042032000020950
Index 8 for Path 42/Row 33 on 07/27/00 = Scene_ID 7042033000020950
Index 8 for Path 42/Row 34 on 07/27/00 = Scene_ID 7042034000020950
Index 9 for Path 43/Row 31 on 06/30/99 = Scene_ID 7043031009918150
Index10 for Path 43/Row 32 on 07/16/99 = Scene_ID 7043032009919750
Index11 for Path 43/Row 33 on 07/18/00 = Scene_ID 7043033000020050
Index12 for Path 44/Row 32 on 07/28/01 = Scene_ID 7044032000120950
LEAF-OFF (Fall)-
Index 1 for Path 39/Row 34 on 10/08/99 = Scene_ID 7039034009928150
Index 2 for Path 40/Row 31 on 10/15/99 = Scene_ID 7040031009928850
Index 3 for Path 40/Row 32 on 09/29/99 = Scene_ID 7040032009927250
Index 2 for Path 40/Row 33 on 10/15/99 = Scene_ID 7040033009928850
Index 2 for Path 40/Row 34 on 10/15/99 = Scene_ID 7040034009928850
Index 4 for Path 41/Row 31 on 09/04/99 = Scene_ID 7041031009924750
Index 4 for Path 41/Row 32 on 09/04/99 = Scene_ID 7041032009924750
Index 5 for Path 41/Row 33 on 10/08/00 = Scene_ID 7041033000028250
Index 5 for Path 41/Row 34 on 10/08/00 = Scene_ID 7041034000028250
Index 6 for Path 42/Row 31 on 09/27/99 = Scene_ID 7042031009927050
Index 7 for Path 42/Row 32 on 09/11/99 = Scene_ID 7042032009925450
Index 6 for Path 42/Row 33 on 09/27/99 = Scene_ID 7042033009927050
Index 8 for Path 42/Row 34 on 10/18/01 = Scene_ID 7042034000129150
Index 9 for Path 43/Row 31 on 10/06/00 = Scene_ID 7043031000028050
Index10 for Path 43/Row 32 on 10/20/99 = Scene_ID 7043032009929350
Index 9 for Path 43/Row 33 on 10/06/00 = Scene_ID 7043033000028050
Index11 for Path 44/Row 32 on 10/19/02 = Scene_ID 7044032000229250

Landsat data and ancillary data used for the land cover prediction -

Data Type of DEM composed of 1 band of Continuous Variable Type.

Data Type of Slope composed of 1 band of Continuous Variable Type.

Data Type of Aspect composed of 1 band of Categorical Variable Type.

Data type of Position Index composed of 1 band of Continuous Variable Type.

Source_Used_Citation_Abbreviation: Landsat ETM, DOQQ, USDA, FIA, DEM, National Center,EROS, IKONOS
Process_Date: Unknown
Source_Produced_Citation_Abbreviation: USGS NLCD
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USGS EROS NLCD 2001
Contact_Person: Jon DeWitz
Contact_Address:
Address_Type: mailing and physical address
Address: USGS EROS
Address: 47914 252nd Street
City: Sioux Falls
State_or_Province: SD
Postal_Code: 57198-0001
Country: USA
Contact_Voice_Telephone: 605-594-2715
Contact_TDD/TTY_Telephone: NA
Contact_Facsimile_Telephone: 605-594-2592
Contact_Electronic_Mail_Address: dewitz@usgs.gov
Hours_of_Service: 0800 - 1600 CT, M - F (-6h CST/-5h CDT GMT)
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Pixel
Row_Count: 19820
Column_Count: 16446
Vertical_Count: 1
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: row and column
Coordinate_Representation:
Abscissa_Resolution: 30.000000
Ordinate_Resolution: 30.000000
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: Layer_1
Entity_Type_Definition: NLDC Land Cover Layer
Entity_Type_Definition_Source: National Land Cover Database 2001
Attribute:
Attribute_Label: ObjectID
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: Count
Attribute_Definition:
A nominal integer value that designates the number of pixels that have each value in the file; histogram column in ERDAS Imagine raster attributes table
Attribute_Definition_Source: NLCD 2001
Attribute_Domain_Values:
Unrepresentable_Domain: Integer
Attribute:
Attribute_Label: Value
Attribute_Definition:
Land Cover Class Code Value. Class definitions marked with an asterisk (*) are Coastal NLCD Classes only.
Attribute_Definition_Source: NLCD 2001
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 1
Enumerated_Domain_Value_Definition: No data value, Alaska zones only
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 11
Enumerated_Domain_Value_Definition:
Open Water - All areas of open water, generally with less than 25% cover or vegetation or soil
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 12
Enumerated_Domain_Value_Definition:
Perennial Ice/Snow - All areas characterized by a perennial cover of ice and/or snow, generally greater than 25% of total cover.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 21
Enumerated_Domain_Value_Definition:
Developed, Open Space - Includes areas with a mixture of some constructed materials, but mostly vegetation in the form of lawn grasses. Impervious surfaces account for less than 20 percent of total cover. These areas most commonly include large-lot single-family housing units, parks, golf courses, and vegetation planted in developed settings for recreation, erosion control, or aesthetic purposes
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 22
Enumerated_Domain_Value_Definition:
Developed, Low Intensity -Includes areas with a mixture of constructed materials and vegetation. Impervious surfaces account for 20-49 percent of total cover. These areas most commonly include single-family housing units.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 23
Enumerated_Domain_Value_Definition:
Developed, Medium Intensity - Includes areas with a mixture of constructed materials and vegetation. Impervious surfaces account for 50-79 percent of the total cover. These areas most commonly include single-family housing units.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 24
Enumerated_Domain_Value_Definition:
Developed, High Intensity - Includes highly developed areas where people reside or work in high numbers. Examples include apartment complexes, row houses and commercial/industrial. Impervious surfaces account for 80 to100 percent of the total cover.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 31
Enumerated_Domain_Value_Definition:
Barren Land (Rock/Sand/Clay) - Barren areas of bedrock, desert pavement, scarps, talus, slides, volcanic material, glacial debris, sand dunes, strip mines, gravel pits and other accumulations of earthen material. Generally, vegetation accounts for less than 15% of total cover.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 32
Enumerated_Domain_Value_Definition:
Unconsolidated Shore* - Unconsolidated material such as silt, sand, or gravel that is subject to inundation and redistribution due to the action of water. Characterized by substrates lacking vegetation except for pioneering plants that become established during brief periods when growing conditions are favorable. Erosion and deposition by waves and currents produce a number of landforms representing this class.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 41
Enumerated_Domain_Value_Definition:
Deciduous Forest - Areas dominated by trees generally greater than 5 meters tall, and greater than 20% of total vegetation cover. More than 75 percent of the tree species shed foliage simultaneously in response to seasonal change.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 42
Enumerated_Domain_Value_Definition:
Evergreen Forest - Areas dominated by trees generally greater than 5 meters tall, and greater than 20% of total vegetation cover. More than 75 percent of the tree species maintain their leaves all year. Canopy is never without green foliage.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 43
Enumerated_Domain_Value_Definition:
Mixed Forest - Areas dominated by trees generally greater than 5 meters tall, and greater than 20% of total vegetation cover. Neither deciduous nor evergreen species are greater than 75 percent of total tree cover.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 51
Enumerated_Domain_Value_Definition:
Dwarf Scrub - Alaska only areas dominated by shrubs less than 20 centimeters tall with shrub canopy typically greater than 20% of total vegetation. This type is often co-associated with grasses, sedges, herbs, and non-vascular vegetation.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 52
Enumerated_Domain_Value_Definition:
Shrub/Scrub - Areas dominated by shrubs; less than 5 meters tall with shrub canopy typically greater than 20% of total vegetation. This class includes true shrubs, young trees in an early successional stage or trees stunted from environmental conditions.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 71
Enumerated_Domain_Value_Definition:
Grassland/Herbaceous - Areas dominated by grammanoid or herbaceous vegetation, generally greater than 80% of total vegetation. These areas are not subject to intensive management such as tilling, but can be utilized for grazing.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 72
Enumerated_Domain_Value_Definition:
Sedge/Herbaceous - Alaska only areas dominated by sedges and forbs, generally greater than 80% of total vegetation. This type can occur with significant other grasses or other grass like plants, and includes sedge tundra, and sedge tussock tundra.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 73
Enumerated_Domain_Value_Definition:
Lichens - Alaska only areas dominated by fruticose or foliose lichens generally greater than 80% of total vegetation.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 74
Enumerated_Domain_Value_Definition:
Moss- Alaska only areas dominated by mosses, generally greater than 80% of total vegetation.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 81
Enumerated_Domain_Value_Definition:
Pasture/Hay - Areas of grasses, legumes, or grass-legume mixtures planted for livestock grazing or the production of seed or hay crops, typically on a perennial cycle. Pasture/hay vegetation accounts for greater than 20 percent of total vegetation.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 82
Enumerated_Domain_Value_Definition:
Cultivated Crops - Areas used for the production of annual crops, such as corn, soybeans, vegetables, tobacco, and cotton, and also perennial woody crops such as orchards and vineyards. Crop vegetation accounts for greater than 20 percent of total vegetation. This class also includes all land being actively tilled.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 90
Enumerated_Domain_Value_Definition:
Woody Wetlands - Areas where forest or shrub land vegetation accounts for greater than 20 percent of vegetative cover and the soil or substrate is periodically saturated with or covered with water.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 91
Enumerated_Domain_Value_Definition:
Palustrine Forested Wetland* -Includes all tidal and non-tidal wetlands dominated by woody vegetation greater than or equal to 5 meters in height and all such wetlands that occur in tidal areas in which salinity due to ocean-derived salts is below 0.5 percent. Total vegetation coverage is greater than 20 percent.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 92
Enumerated_Domain_Value_Definition:
Palustrine Scrub/Shrub Wetland* - Includes all tidal and non-tidal wetlands dominated by woody vegetation less than 5 meters in height, and all such wetlands that occur in tidal areas in which salinity due to ocean-derived salts is below 0.5 percent. Total vegetation coverage is greater than 20 percent. The species present could be true shrubs, young trees and shrubs or trees that are small or stunted due to environmental conditions.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 93
Enumerated_Domain_Value_Definition:
Estuarine Forested Wetland* - Includes all tidal wetlands dominated by woody vegetation greater than or equal to 5 meters in height, and all such wetlands that occur in tidal areas in which salinity due to ocean-derived salts is equal to or greater than 0.5 percent. Total vegetation coverage is greater than 20 percent.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 94
Enumerated_Domain_Value_Definition:
Estuarine Scrub/Shrub Wetland* - Includes all tidal wetlands dominated by woody vegetation less than 5 meters in height, and all such wetlands that occur in tidal areas in which salinity due to ocean-derived salts is equal to or greater than 0.5 percent. Total vegetation coverage is greater than 20 percent.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 95
Enumerated_Domain_Value_Definition:
Emergent Herbaceous Wetlands - Areas where perennial herbaceous vegetation accounts for greater than 80 percent of vegetative cover and the soil or substrate is periodically saturated with or covered with water.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 96
Enumerated_Domain_Value_Definition:
Palustrine Emergent Wetland (Persistent)* - Includes all tidal and non-tidal wetlands dominated by persistent emergent vascular plants, emergent mosses or lichens, and all such wetlands that occur in tidal areas in which salinity due to ocean-derived salts is below 0.5 percent. Plants generally remain standing until the next growing season.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 97
Enumerated_Domain_Value_Definition:
Estuarine Emergent Wetland* - Includes all tidal wetlands dominated by erect, rooted, herbaceous hydrophytes (excluding mosses and lichens) and all such wetlands that occur in tidal areas in which salinity due to ocean-derived salts is equal to or greater than 0.5 percent and that are present for most of the growing season in most years. Perennial plants usually dominate these wetlands.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 98
Enumerated_Domain_Value_Definition:
Palustrine Aquatic Bed* - The Palustrine Aquatic Bed class includes tidal and nontidal wetlands and deepwater habitats in which salinity due to ocean-derived salts is below 0.5 percent and which are dominated by plants that grow and form a continuous cover principally on or at the surface of the water. These include algal mats, detached floating mats, and rooted vascular plant assemblages.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Enumerated_Domain:
Enumerated_Domain_Value: 99
Enumerated_Domain_Value_Definition:
Estuarine Aquatic Bed* - Includes tidal wetlands and deepwater habitats in which salinity due to ocean-derived salts is equal to or greater than 0.5 percent and which are dominated by plants that grow and form a continuous cover principally on or at the surface of the water. These include algal mats, kelp beds, and rooted vascular plant assemblages.
Enumerated_Domain_Value_Definition_Source: NLCD 2001 land cover class descriptions
Attribute:
Attribute_Label: Red
Attribute_Definition:
Red color code for RGB slice by value for canopy image display purposes. The value is arbitrarily assigned by the display software package, unless defined by user. Standard user defined ramp for NLCD project is start color light gray, end color red.
Attribute_Definition_Source: NLCD 2001
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 100
Attribute_Units_of_Measure: CSS Color Value Percentage
Attribute_Measurement_Resolution: 0.1
Attribute:
Attribute_Label: Green
Attribute_Definition:
Green color code for RGB slice by value for canopy image display purposes. The value is arbitrarily assigned by the display software package, unless defined by user. Standard user defined ramp for NLCD project is start color light gray, end color red.
Attribute_Definition_Source: NLCD 2001
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 100
Attribute_Units_of_Measure: CSS Color Value Percentage
Attribute_Measurement_Resolution: 0.1
Attribute:
Attribute_Label: Blue
Attribute_Definition:
Blue color code for RGB slice by value for canopy image display purposes. The value is arbitrarily assigned by the display software package, unless defined by user. Standard user defined ramp for NLCD project is start color light gray, end color red.
Attribute_Definition_Source: NLCD 2001
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 100
Attribute_Units_of_Measure: CSS Color Value Percentage
Attribute_Measurement_Resolution: 0.1
Attribute:
Attribute_Label: Opacity
Attribute_Definition:
A measure of how opaque, or solid, a color is displayed in a layer.
Attribute_Definition_Source: NLCD 2001
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 100
Attribute_Units_of_Measure: Percentage
Attribute_Measurement_Resolution: 0.1
Overview_Description:
Entity_and_Attribute_Overview:
Attributes defined by USGS and ESRI.
Class Red Green Blue
0 0.000000000 0.000000000 0.000000000
1 0.000000000 1.000000000 0.000000000
11 0.325490196 0.462745098 0.662745098
12 0.854901961 0.913725490 1.000000000
21 0.913725490 0.819607843 0.815686275
22 0.890196078 0.615686275 0.545098039
23 0.976470588 0.000000000 0.000000000
24 0.705882353 0.000000000 0.000000000
31 0.741176471 0.725490196 0.670588235
32 1.000000000 1.000000000 1.000000000
41 0.443137255 0.701960784 0.419607843
42 0.137254902 0.423529412 0.231372549
43 0.752941176 0.827450980 0.607843137
51 0.694117647 0.588235294 0.235294118
52 0.835294118 0.764705882 0.533333333
71 0.925490196 0.925490196 0.796078431
72 0.823529412 0.823529412 0.505882353
73 0.635294118 0.796078431 0.321568627
74 0.513725490 0.725490196 0.619607843
81 0.901960784 0.882352941 0.282352941
82 0.709803922 0.486274510 0.200000000
90 0.760784314 0.878431373 0.949019608
95 0.486274510 0.674509804 0.772549020
Entity_and_Attribute_Detail_Citation:
Attribute accuracy is described, where present, with each attribute defined in the Entity and Attribute Section. Note: To ensure all areas of mapping zone 12 are completely covered, a 3,000 meter (100 Landsat pixels) buffer was added to the boundary of mapping zone 12.
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Position: Customer Service Representative
Contact_Address:
Address_Type: mailing and physical address
Address: USGS/EROS
Address: 47914 252nd Street
City: Sioux Falls
State_or_Province: SD
Postal_Code: 57198-0001
Country: USA
Contact_Voice_Telephone: 605/594-6151
Contact_TDD/TTY_Telephone: 605/594-6933
Contact_Facsimile_Telephone: 605/594-6589
Contact_Electronic_Mail_Address: custserv@usgs.gov
Hours_of_Service: 0800 - 1600 CT, M - F (-6h CST/-5h CDT GMT)
Contact_Instructions:
The USGS point of contact is for questions relating to the data display and download from this web site. Questions about the NLCD mapping zone 12 can be directed to the NLCD 2001 land cover mapping team at the USGS/EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov.
Resource_Description: Downloadable data
Distribution_Liability:
Although these data have been processed successfully on a computer system at the USGS, no warranty expressed or implied is made by the USGS regarding the use of the data on any other system, nor does the act of distribution constitute any such warranty. Data may have been compiled from various outside sources. Spatial information may not meet National Map Accuracy Standards. This information may be updated without notification. The USGS shall not be liable for any activity involving these data, installation, fitness of the data for a particular purpose, its use, or analyses results.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: Arc/Info Export Format and/or ArcView Shapefile
Format_Version_Number: ArcGIS 9.0
Format_Specification: ASCII
Transfer_Size: 0.001
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: <http://seamless.usgs.gov>
Access_Instructions:
The URL <http://seamless.usgs.gov> provides a map interface that allows for data downloads within a customer defined area of interest. Zoom tools are available that can be used to investigate areas of interest on the map interface. The download tool allows the customer to capture layers from the map, utilizing the Seamless Data Distribution System process for downloading. A request summary page is then generated with the download layers listed. By clicking the "download" button on the summary page, a zipped file will be generated that can be saved on the customer's computer. The file can then be unzipped and imported into various user software applications.
Online_Computer_and_Operating_System: Not available for dissemination
Fees: None
Ordering_Instructions: Contact Customer Services
Turnaround: Variable
Custom_Order_Process: Contact Customer Services Representative
Technical_Prerequisites:
ESRI ArcMap Suite and/or Arc/Info software, and supporting operating systems.
Metadata_Reference_Information:
Metadata_Date: 20060301
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Position: Customer Services Representative
Contact_Address:
Address_Type: mailing and physical address
Address: USGS/EROS
Address: 47914 252nd Street
City: Sioux Falls
State_or_Province: SD
Postal_Code: 57198-0001
Country: USA
Contact_Voice_Telephone: 605/594-6151
Contact_TDD/TTY_Telephone: 605/594-6933
Contact_Facsimile_Telephone: 605/594-6589
Contact_Electronic_Mail_Address: custserv@usgs.gov
Hours_of_Service: 0800 - 1600 CT, M - F (-6h CST/-5h CDT GMT)
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Access_Constraints: None
Metadata_Use_Constraints: None
Metadata_Security_Information:
Metadata_Security_Classification_System: None
Metadata_Security_Classification: None
Metadata_Security_Handling_Description: None
Metadata_Extensions:
Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile
Generated by mp version 2.8.6 on Wed Mar 01 11:40:00 2006