Journal of Environmental Management (1996) 46, 77–94
Simulating the Effects of Alternative Forest Management Strategies
on Landscape Structure
Eric J. Gustafson and Thomas R. Crow
U.S. Department of Agriculture, Forest Service, North Central Forest Experiment
Station, Forestry Sciences Laboratory, Rhinelander, WI 54501, U.S.A.
Received 27 February 1995
Quantitative, spatial tools are needed to assess the long-term spatial consequences
of alternative management strategies for land use planning and resource
management. We constructed a timber harvest allocation model (HARVEST)
that provides a visual and quantitative means to predict the spatial pattern of
forest openings produced by alternative harvest strategies. HARVEST was used
to investigate the effect on landscape structure of alternate management plans
formulated for the Hoosier National Forest (HNF) in southern Indiana, U.S.A.
The 1985 Forest Plan for the HNF specified primarily clearcutting across most of
the forest, and the 1991 Amended Forest Plan specified primarily group selection
(removal of small groups of trees), limited to a much smaller portion of the forest.
We assessed the relative importance of variation in the extent and intensity of
timber harvest on landscape spatial pattern. We simulated 150 years for each
alternative and calculated several measures of forest spatial pattern. The total
area of forest interior and the mean size of forest interior blocks declined more
under the 1985 Plan than under the 1991 Plan, primarily because of the greater
area dedicated to timber production in the 1985 Plan. Despite the 65% decrease in
timber production in the 1991 Plan, that Plan produced almost as much forest
edge as the 1985 Plan due to heavy reliance on small harvests with large
perimeter-to-area ratios. Both Plans resulted in an even distribution of age classes
up to the age equal to rotation length, a dramatic decline in mid-age classes, and a
large area of mature forest. The restriction of harvest activity to more limited
areas in the 1991 Plan appeared to have a greater effect on forest spatial pattern
than did the differences in harvest intensity of the two Plans. HARVEST provides
a tool to link planning alternatives with potential changes in landscape structure,
commodity production, and other resource values that are spatially dependent.
1996 Academic Press Limited
Keywords: forest management planning, landscape ecology, simulation models,
habitat fragmentation, forest interior, forest edge, clearcutting, age-class
distribution, biological diversity, spatial pattern, scale.
1. Introduction
Provisions of the National Forest Management Act of 1976 (NFMA) require the U.S.
Department of Agriculture Forest Service to complete a plan for each National Forest
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0301–4797/96/010077+18 $12.00/0 1996 Academic Press Limited