Land Developed, 1982 - 1997
This shaded polygon map shows the change in the amount of developed land (urban areas and rural transportation land) area from 1982 to 1997 within each 8-digit hydrologic unit. The groupings are presented in four categories based on the following divisions: an increase of more than 50,000 acres, an increase of 25,000 to 50,000 acres, an increase of 15,000 to 25,000 acres, and an increase of less than 15,000. There was a total of 25,005,900 acres developed. Metropolitan Statistical Areas are indicated by black squares. Areas with 95% or more federal area are shaded gray.
Cautions for this Product:
This map does not show the total amount of developed land. Data are not collected on Federal land. Data are not available for Alaska or the Pacific Basin. Data for Puerto Rico and the U.S. Virgin Islands is shown by 6-digit hydrologic unit.
Source: National Resources Inventory, 1997
NRI sample data are generally reliable at the 95% confidence interval for state and certain broad substate area analyses. Generally, analyses that aggregate data points by smaller geographic areas and/or more specific criteria result in fewer data points for each aggregation and therefore less reliable estimates. NRI maps reflect national patterns rather than site- specific information.
Aggregate Layer: 8 Digit Hydrologic Unit Areas with Federal Land
Other Layers Displayed: States, Rivers, Metropolitan Statistical Area (MSA) Lat/Long selections from GNIS
A combination of land cover/use categories, Urban and built-up areas, and Rural Transportation Land.
A land ownership class designating land that is owned by the Federal Government. It does not include, for example, trust lands administered by the Bureau of Indian Affairs nor Tennessee Valley Authority (TVA) land. No data are collected for any year that land is in this ownership. [NRI-97]
A hierarchical system developed by the U.S. Geological Survey that divides the United States and the Caribbean into 21 major regions, 222 subregions, 352 accounting units, and further subdivided into 2,150 cataloging units that delineate river basins having drainage areas usually greater than 700 square miles. [USGS]
Metropolitan Statistical Areas:
Generally, these are defined as areas that include counties with central cities of 250,000 or more inhabitants (for additional details, contact Bureau of the Census)
Rural transportation land:
A Land Cover/Use category which consists of all highways, roads, railroads and associated rights- of-way outside urban and built-up areas; including private roads to farmsteads or ranch headquarters, logging roads, and other private roads, except field lanes. [NRI-97]
Urban and built-up areas:
A Land Cover/Use category consisting of residential, industrial, commercial, and institutional land; construction sites; public administrative sites; railroad yards; cemeteries; airports; golf courses; sanitary landfills; sewage treatment plants; water control structures and spillways; other land used for such purposes; small parks (less than 10 acres) within urban and built-up areas; and highways, railroads, and other transportation facilities if they are surrounded by urban areas. Also included are tracts of less than 10 acres that do not meet the above definition but are completely surrounded by Urban and Built-up land. Two size categories are recognized in the NRI: (i) areas 0.25 to 10 acres, and (ii) areas greater than 10 acres. [NRI-97]
Product ID: 5009
Production Date: 12/13/00
Product Type: Map
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