Estimated distribution of historical grassland communities of the Southern Great Plains

The purpose of this project was to map the potential distribution of grassland communities of the Southern Great Plains prior to Euro-American settlement. The Southern Great Plains REA, under the direction of the Bureau of Land Management and the Great Plains Landscape Conservation Cooperative, includes the High Plains, Central Great Plains, Southwestern Tablelands and the Nebraska Sand Hills ecoregions (and an adjacent buffer delineated by fifth-level watersheds intersecting the ecoregion boundaries), and encompasses the full extent of the Great Plains Landscape Conservation Cooperative. The REA advisors and stakeholders determined that the mapping accuracy of available national land-cover maps were insufficient in many areas to adequately address management questions for the REA. Based on the recommendation of the REA stakeholders, we estimated the potential historical distribution of 10 grassland communities within the project area, which is dominated by shortgrass, mixed-grass and sand prairies, using data on soils, climate, and vegetation from the Natural Resources Conservation Service (NRCS) including the Soil Survey Geographic Database (SSURGO) and Ecological Site Information System (ESIS). Grassland communities were primarily defined using the annual productivity of dominant species in the ESIS data. The historical grassland community classification was linked to the SSURGO data using vegetation types associated with the predominant component of mapped soil units as defined in the ESIS. We augmented NRCS data with LANDFIRE Biophysical Settings classifications: 1) where NRCS data were unavailable and 2) in watersheds intersected by ecoregion boundaries. Spatial data representing the estimated distribution of historical grassland communities of the Southern Great Plains are provided as a 30 x 30-meter (m) gridded surface (raster dataset). This information will help to address the priority management questions for grassland communities for the Southern Great Plain REA and can be used to inform other regional-level land management decisions.