This regional landcover dataset was produced using decision tree classification and other techniques to model landcover. Multi-season satellite imagery (Landsat ETM+, 1999-2003) and digital elevation model (DEM) derived datasets (e.g. elevation, landform, aspect, etc.) were utilized to derive rule sets for the various landcover classes. These land cover classes were drawn from NatureServe's Ecological System concept and a description of the mapped ecological systems can be found in the .pdf document, Land Cover Legend: Current Distribution of Sagebrush and Associated Vegetation in the Columbia Basin and Southwestern Regions.

These spatial data are available in three spatial extents: regional, state, and mapping zone.

Regional:

The regional data set includes an 8 state area (AZ, CO, ID, NM, NV, OR, UT WA) and is a compilation of the Columbia Basin and Southwest GAP datasets. The zip file contains a folder with the ArcInfo grid dataset, ArcGIS layer file, FGCD metadata file , .dbf lookup table and land cover class descriptions.

State:

We serve state-level data for Idaho, Oregon, and Washington. Data for the other 5 states can be obtained from the Southwest Regional GAP Program . The state-level download is a zip file containing the ArcInfo grid dataset, ArcGIS layer file, FGCD metadata file , .dbf lookup table and a .pdf document of land cover class descriptions.

Map Zone:

The eleven mapping zones, each defined by ecological and spectral characteristics, were modeled independently of one another. Methodology and accuracy, therefore, differ among the zones. Each mapping zone level zip file contains an ArcInfo grid dataset, ArcGIS layer file, FGCD metadata file, .dbf lookup table, land cover class description, and a zone-specific .pdf document describing methodology and a zonal accuracy assessment which may be downloaded seperately.