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Summary:

Human use of the land has a large effect on the structure of terrestrial ecosystems and the dynamics of biogeochemical cycles. For this reason, terrestrial ecosystem and biogeochemistry models require moderate resolution information on land use in order to make realistic predictions. Few such datasets currently exist.

The Land Use Mapping Project collection consists of output from models that estimate the spatial pattern of land use in four land-use categories by relating a high-resolution land-cover dataset to state-level census data on land use. The models have been parameterized using a goodness-of-fit measure.

The land cover product used was from the IGBP DISCover global product, derived from 1 km AVHRR imagery, with 16 land cover classes (Belward et al., 1999). Land-use data at state-level resolution came from the USDA's Major Land Uses database (USDA, 1996), aggregated into the four general land-use categories described below.

The model was used to generate maps of land use in 1992 for the conterminous U.S. at 0.5 degree spatial resolution. Two different parameterization schemes were used to spatially interpolate land use from land cover, based on the state-level land use census data: 1) a National Parameterization, and 2) a Regional Parameterization.

For the National Parameterization, a single parameterization relating aggregate land cover and state-level land use. For the Regional Parameterization, a separate parameterization was used for each of seven different regions. The seven regions include: Northeast, Southeast, East North-central, West North-central, Southern Plains, Mountain, and Pacific. These regions are substantially different in terms of land use and land cover. In both cases, the results are a nationally gridded map at 0.5 degrees of land use categories for cropland, pasture/range, forest, and other land use; the other land use category is also further spilt into three additional subcategories (forested, non-forested, non-vegetated).

This project is currently being extended to other regions of the globe, and for other time periods, where both land use census data and image-derived land cover data are available.

Available Data Sets:

Table 1

Spatial & Temporal Scales

US Land Use – 1992 National Param Dataset &

US Land Use – 1992 Regional Param Dataset

These data are gridded in the geographic projection with 0.5 degree by 0.5 degree cell sizes. The data are bounded by 50.0 N to 23.0 N latitude, and by 65.5 W to 125.5 W longitude. The data represent a snapshot of the time period covered by the census data & land cover data: 1992.

Data Format

US Land Use – 1992 National Param Dataset &

US Land Use – 1992 Regional Param Dataset

The full dataset contains 120 cells in the x-dimension (longitude) and 54 cells in the y-dimension (latitude) of floating point data. The fill value for missing data and non-land/sea mask is –99.99.

Variable Description:

US Land Use – 1992 National Param Dataset &

US Land Use – 1992 Regional Param Dataset

a) Major Land Use Categories

Estimates of the percent of land use area per grid cell are provided for each of four land use categories: cropland, pasture/range, forest, and other. These estimates are based on the national parameterization of the model. Each grid cell is 0.5 degrees and was estimated using 1992 land use census data and AVHRR-derived land cover classification (see references).

b) Subcategories of Other Land Use

Estimates of the percent of Other land use are provided for three subcategories: forested other, non-forested other, and non-vegetated other land uses. These subcategories account for land cover classifications or land use categories which were classed as other because they represent urban areas, wetland, snow & ice, national and state parks, wildlife refuges, or defense lands. Each grid cell is 0.5 degrees and was estimated using 1992 land use census data and AVHRR-derived land cover classification (see references).

Model Inputs:

US Land Use – 1992 National Param Dataset &

US Land Use – 1992 Regional Param Dataset

The land cover product used was from the IGBP DISCover global product (Belward et al., 1999), derived from 1 km AVHRR imagery, with 16 land cover classes. Land use data at state-level resolution came from the USDA's Major Land Uses database (USDA, 1996), aggregated into the four general land use categories discussed above. See reference for more details & specific parameters used in this model.

References:

Belward, AS, J.E. Estes, K.D. Kline. 1999. The IGBP-DIS global 1-km land-cover data set DISCover: a project overview. Photogram. Engineer. Rem. Sen. 65:1013-1020.

Hurtt, G.C., L. Rosentrater, S. Frolking, B. Moore III. 2001. Linking remote-sensing estimates of land cover and census statistics on land use to produce maps of land use of the conterminous United States. Global Biogeochemical Cycles, Global Biogeochemical Cycles, 15: 673-685.

USDA. 1996. Major Land-Uses (1945-1992). Technical Report. USDA. Washington, D.C.

Data Providers:

Dr. George C. Hurtt, Complex Systems Research Center; Institute for the Study of Earth, Oceans and Space; Morse Hall; University of New Hampshire; Durham, New Hampshire 03824; Ph: 603.862.1792; Fax: 603.862.0188; Email: george.hurtt@unh.edu

Dr. Steve Frolking, Complex Systems Research Center, Institute for the Study of Earth, Oceans, and Space, Morse Hall, University of New Hampshire, Durham, New Hampshire, USA. Ph: 603.862.1792, Fax: 603.862.0188, Email: steve.frolking@unh.edu.

Latest Data Update:

3/21/2001

Last Doc. Updated:

3/30/2001

Doc. Updated By:

Shannon Spencer

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