Major ecosystems have been mapped and described for the State of Alaska
and nearby areas. Ecoregion units are based on newly available datasets
and field experience of ecologists, biologists, geologists and regional
experts. Recently derived datasets for Alaska included climate
parameters, vegetation, surficial geology and topography. Additional
datasets incorporated in the mapping process were lithology, soils,
permafrost, hydrography, fire regime and glaciation. Thirty two units
are mapped using a combination of the approaches of Bailey
(hierarchial), and Omernick (integrated). The ecoregions are grouped
into two higher levels using a tri-archy-based on climate parameters,
vegetation response and disturbance processes. The ecoregions are
described with text, photos and tables on the published map.