Acres of Non-Federal Developed Land, 1987
This dot density map shows the total number of 1987 developed land acres aggregated by 8-digit hydrologic unit. Developed land includes urban and built-up areas and rural transportation land. Each red dot = 15,000 acres. Metropolitan Statistical Areas (MSAs) are shaded beige. The MSA Central Cities are indicated by black squares. Areas with 95% or more Federal area are shaded gray.
Cautions for this Product:
This map may not be used to determine site- specific information. Within an 8-digit hydrologic unit, dot counts represent acreage totals correctly plus or minus one dot to account for remainders. 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 are aggregated 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: Cross of State with 8 Digit Hydrologic Units and Federal Land
Other Layers Displayed: States, Rivers, Metropolitan Statistical Area (MSA) Lat/Long selec 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]
A term that includes categories of land cover and categories of land use. Land cover is the vegetation or other kind of material that covers the land surface. Land use is the purpose of human activity on the land; it is usually but not always related to the land cover. The NRI uses the term (land cover/use) to identify the categories that account for all the surface area in the United States [BS-1982; NRI-97]
Metropolitan Statistical Area (MSA):
A geographic entity, defined by the Federal OMB for use by Federal statistical agencies, based on the concept of a core area with a large population nucleus, plus adjacent communities having a high degree of economic and social integration with that core. Qualifications of an MSA requires the presence of a city with 50,000 or more inhabitants, or the presence of an Urban Area and a total population of at least 100,000 (75,000 in New England). The county or counties containing the largest city and surrounding densely settled territory are central counties of the MSA. Additional outlying counties qualify to be included in the MSA by meeting certain other criteria of metropolitan character, such as a specified minimum population density or percentage of the population that is urban. MSA's in New England are defined in terms of cities and towns, following rules concerning commuting and population density. MSA's were first defined and effective June 30, 1993.
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: 5986
Production Date: 5/7/01
Product Type: Map
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