A total of 125 land cover classes were mapped for the five-state region. One hundred and nine are considered natural or semi-natural land cover classes. The remaining land cover classes are disturbed natural or anthropogenic land cover/use classes. The basic thematic mapping unit for natural and semi-natural land cover classes is the ecological system developed by NatureServe. Ecological systems represent recurring groups of biological communities found in similar physical environments and influenced by similar dynamic ecological processes, such as fire or flooding. They are intended to provide a thematic mapping unit that is mappable at a meso-scale level often from remotely sensed imagery.
Recommended citation for detailed legend descriptions document:
USGS National Gap Analysis Program. 2005. Southwest Regional GAP Analysis Project—Land Cover Descriptions. RS/GIS Laboratory, College of Natural Resources, Utah State University.
For more information on the ecological system concept, visit NatureServe.org
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