Gap Analysis consists of three main data layers, a landcover layer, a layer showing the predicted distributions of vertebrate species, and a stewardship layer.
I. Map land cover of the dominant plant species.
The first step of gap analysis is to map vegetation to the alliance level. Alliances are natural assemblages of plant species. They are used because the patterns of natural terrestrial landcover are a reflection of the physical and chemical factors that shape the environment of a given land area.
Plants are also determinate for overall biological diversity as their structures and composition significantly affect species-level interactions.
Landcover is mapped using Landsat Thematic Mapper raw and hypercluster imagery from the Eros Data Center's Multi-Resolution Land Characteristics Consortium (MRLC) program. MRLC is the federal consortium for obtaining, processing, and archiving satellite imagery.
Other information sources include: existing maps and other records, air photos; air video; and ground points. |