Alaskan portion of the Circumboreal Vegetation Map
M. Torre JORGENSON
Alaska Ecoscience, Fairbanks, AK, USA
A map of boreal vegetation in Alaska is being developed as a contribution to
the circumboreal vegetation mapping (CBVM) project. The effort included classification
and mapping of six bioclimatic zones for boreal Alaska that provided
the basis for classification of boreal vegetation. Vegetation mapping for Alaska
is being done at 1:7.5 million scale using the protocol by the CBVM team. Mapping
uses an integrated-terrain-unit approach that includes classifications for
bioclimate, physiography, generalized geology, permafrost, disturbance, growth
form, geographic sector, water coverage, and vegetation. Vegetation is mapped
at five hierarchical levels: (1) formation type based on physiognomy and structure;
(2) formation group differentiating zonal, extrazonal, and azonal systems; (3) formation
based on dominant growth forms with finer subdivisions than Level 1; (4)
bioclimatic subdivision based on temperature and precipitation indices; and (5)
geographic sectors based on dominant species that characterize broad longitudinal
regions or floristic provinces. The boreal vegetation classification for Alaska
tentatively has 35 classes at Level 5. Nearly half of the mapping for Alaska has
been completed and the remaining portion will be completed by the end of 2012.
Future work will focus on integrating the classification, mapping, and GIS database
into a North American map, and then with the other circumboreal regional efforts.
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© 2012 Organizing Committee
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