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National Resources Inventory
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Key Findings
Importance to the NationLand use is surprisingly dynamic, with annual shifts in and out of different uses. Examining net change in land use reveals general trends, but masks the real extent of land use change over time. In agriculture there are frequent shifts in the use of land among cropland, pastureland, rangeland, and forest land. Each time land changes use, it may affect erosion potential, contiguity of habitat, or hydrologic features of the landscape. Cropland, pastureland, rangeland, and forest land comprise the majority of the Nation’s land resources and thus:
Tabular ResultsMore InformationFor more information about the NRI, visit http://www.nrcs.usda.gov/technical/NRI/ See the 2003 Annual NRI Glossary for definitions of key terms. Send comments and questions to the NRI Help Desk |
About the DataEstimates presented here are based upon the latest information from the National Resources Inventory (NRI). The NRI is a longitudinal sample survey based upon scientific statistical principles and procedures. It is conducted by the U.S. Department of Agriculture’s Natural Resources Conservation Service (NRCS), in cooperation with Iowa State University’s Center for Survey Statistics and Methodology. These results are based upon the 2003 Annual NRI, which statistically updates 1997 NRI results with data collected during 2000 - 2003. The NRI was conducted on a five-year cycle during the period 1982 to 1997, but is now conducted annually. NRI data were collected every five years for 800,000 sample sites; annual NRI data collection occurs at slightly less than 25 percent of these same sample sites. NRI data release procedures are affected by implementation of an annual data collection approach, because the scale of NRI estimates is affected by these reduced sample sizes. Estimates are being released when they meet statistical standards and are scientifically credible in accordance with NRCS policy, and in accordance with OMB and USDA Quality of Information Guidelines. The 2003 Annual NRI data are suitable for national and many regional and state level analyses. Current estimates cover the contiguous 48 states. Future estimates will also cover Hawaii, Alaska, the Caribbean, and selected Pacific Basin islands. The findings on land use come from the NRI data category "Land Cover/Use," which comprises mutually exclusive categories such as cropland, rangeland, forest land, other rural land, developed land, and water areas. The NRI uses this classification to account for each and every acre of non-Federal land within the Nation. Every parcel of land is described by one and only one of these categories. The NRI approach to conducting inventories facilitates examination of trends in land use over time because -
Irrespective of the scale of analysis, margins of error must be considered. Margins of error (at the 95 percent confidence level) are presented for all NRI estimates. |
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