plicated, we have chosen to emphasize only human
did not perform hierarchical grouping of inte-
disturbance in our classification of ecosystems.
grated units (Walker et al. 1980). Recently, an
Beyond this conceptual framework of state fac-
integrated-terrain unit approach has been used for
tor control, however, there is no single natural
large-scale mapping of ecosystems on the Arctic
scale at which ecological phenomena should be
Coastal Plain (Jorgenson et al. 1997) and vegeta-
studied, leading observers to impose their own
tion complexes across the entire North Slope
perceptual bias in the study of the patterns and
(Walker 1997). In interior Alaska, land cover map-
processes of ecological phenomena (Levin 1992,
ping has been done for the Tanana Valley and
Shugart 1998). In addition, there is no nationally
adjacent Alaska Range by the Bureau of Land
accepted approach to classifying ecosystems,
Management (USBLM 1997).
although recent efforts have been made to develop
Spatial databases developed from an ecological
a consensus among federal agencies (ECOMAP
land classification are essential to managing land
1993) and among nations (Uhling and Jordan
resources and have many applications, such as
1996, Klijn and Udo de Haes 1994). In this report,
use in ecological risk assessments, analysis of ter-
we generally have followed the scales and differ-
rain sensitivity and wildlife habitats, wetland
entiating criteria described by Klijn and Udo de
mitigation, planning for training exercises, facil-
Haes (1994), which combines elements of both the
ity location, identification of rare habitats, and fire
Canadian (Wiken and Ironside 1977) and U.S. sys-
management. By delineating areas with covarying
tems (ECOMAP 1993). This system involves numer-
climate, geomorphology (surficial geology, terrain
ous spatial scales for mapping ecosystems and
units), surface-forms, hydrology, and biota, the
identifies various ecosystem components as the
resulting maps provide a spatial stratification that
prime criteria for differentiating successive levels
is particularly useful for integrated resource man-
of hierarchical organization.
agement based on GIS. This hierarchy of scales
In this report, we evaluate and present three lev-
can help land managers and military trainers
els of ecosystem organization, ecotypes (1:50,000
access information, identify information gaps,
scale), ecosections (1:100,000), and ecodistricts
and improve resource management of large areas.
(1:500,000). Ecotypes (also referred to as local eco-
Applications of the spatial databases produced by
systems, ecotopes, land type phases, or vegetation
this project already include delineation of juris-
types) delineate areas with homogenous topogra-
dictional wetlands (Lichvar and Sprecher 1998),
phy, terrain, soil, surface form, hydrology, and
analysis of permafrost occurrence and degrada-
vegetation. Ecosections (also landscapes, land type
tion (Racine et al., in prep.), and stratification of
associations, or geomorphic sections) are homo-
monitoring locations for the Land Condition and
Trends Analysis Program∗ .
geneous with respect to geomorphic features and
have recurring patterns of water regimes, soils,
and vegetation. Although several vegetation
classes can be included in an ecosection, the
STUDY AREA
vegetation classes usually are related because
Fort Wainwright is located near Fairbanks in
they occur as different stages in a successional
central Alaska and covers approximately 368,467
sequence. Ecodistricts (or subregions, physi-
ha (910,498 acres) of land (Fig. 2). Three major
ographic districts) are broader areas with similar
portions of the military base include the canton-
geology, geomorphology, and hydrology. Eco-
ment area with most of the facility structures, the
regions (or climatic zones), which differentiate
Yukon Maneuver Area (104,503 ha), where most
areas based on their climatic regimes and gross
of the troop and aircraft exercises occur, and the
physiography, have been mapped recently for
Tanana Flats (263,964 ha, including a portion
Alaska by Gallant et al. (1995), although their cri-
north of Tanana River), where occasional aircraft
teria differed slightly from the above-mentioned
training takes place. In addition, several small
organizational frameworks.
parcels of military land in the Fairbanks area are
In Alaska, a hierarchical approach to vegetation
near the cantonment area.
and land cover mapping has been developed for
The continental climate of interior Alaska has
northern Alaska by Walker and his colleagues
extreme annual temperature variations, low
(Walker 1983, Walker et al. 1989, Walker and
Walker 1991). They also applied an integrated,
geobotanical approach to mapping ecosystem
* C. Bagley, Center for Ecological Management of Military
components in the Prudhoe Bay region, but they
Lands, Fort Collins, Colorado, pers. comm. 1998.
3
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