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THE NATIONAL RESOURCES INVENTORY. Wayne A. Fuller Sarah Nusser and Jeff Goebel Roles of Statistics in 21 st Century Monitoring and Assessment Systems Denver September, 2004. The Natural Resources Inventory (NRI). A nationwide survey of non federal land Conducted by
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THE NATIONAL RESOURCES INVENTORY Wayne A. Fuller Sarah Nusser and Jeff Goebel Roles of Statistics in 21st Century Monitoring and Assessment Systems Denver September, 2004
The Natural Resources Inventory (NRI) A nationwide survey of non federal land Conducted by Natural Resources Conservation Service (NRCS) Technical support by Iowa State University
Outline History 1982-1997 National Resources Inventories Estimation-imputed points Annual Inventory
History Nusser and Goebel (EES, 1997) • National Erosion Reconnaissanc Survey: Anecdotal (SCS) • National Inventory of Soil and Water Conservation Needs (CNI): Stratified area sample of segments (40,160,640 acres) • CNI: 38 Points within 160 Acre segments 1958 Segments
History (continued) • National Resources Inventory: Subsample of 1958 sample. Segment Acres for built up, farmsteads, water, streams. Three points per 160 acre segment, 70,000 segments. • National Resources Inventory: New sample in 13 Northern states. 321,000 National, 44,000 local segments. Three points per 160 acres. • NRI: Subsample of 108,000 of 1982 sample.
History (continued) • NRI: 300,000 segments (some retrospective 1987 data). • NRI: 300,000 segments. Three points per 160 acres. 2000-200? NRI: 70,000 segments per year, 40,000 core every year. Subsamples of 1997 NRI.
Data Collection Photo – interpretation Segment acres of built-up, water Land coveruse of points NRCS Field Offices Cropping practices Conservation Reserve Program (CRP)
1982-1997 NRI Longitudial survey. Almost same segments every year External controls. Large Water, Federal Combination of segment and point data Complete easy-to-use databases
1992 – 1997 Estimation Sources of Data Sample Segment Point Auxiliary Large Water and Large Streams Federal and county area Administrative – CRP Hydrologic units (5000 HUCCOs)
Geospatial Data for a County County boundary 4-digit HUA boundary Federal land in 92 & 97 97 Federal land in 97 only Census water in 92 & 97 1 PSU (Segment) 3 2 92, 97 1 HUCCO id 92, 97
Segment Sketch 1 2 Road Urban 97 Urban 82, 87, 92, 97 3
Imputed Points Probability of selecting donor coveruse Imputed estimated total close to two-phase estimate Fuller (2003)
1997 Data Set Set of points – ratio adjusted probability weights Acres for HUCCOs match administrative Estimates close to those of previous years
Annual NRI Subsamples of 1997 NRI Supplemented Panel Design Core Panel every year Rotate supplementary panels 4-10 years to complete rotation
Generalized Least Squares Vector of year-panel means is “y” vector Vector of year means is “” vector Breidt and Fuller (JABES, 1999)
Estimation for Annual NRI Example: Impute 2000 for 2001 supplement Nearest Neighbor donor Direct estimates of large change
Reasons for Success Demand for information Adaptability and improvement (i) Cost structure (ii) Data: erosion, urban, CRP, wetlands (iii) Collection and processing techniques (iv) Auxiliary information-Geostatistical People and institutions