HR: 11:35h
AN: GC32A-06 INVITED [Abstracts]
TI: Effects of a Warmer Climate on Stress Complexes in Forests of Western North America
AU: * Peterson, D L
EM: peterson@fs.fed.us
AF: USDA Forest Service, Pacific Northwest Research Station, 400 N. 34th Street, Suite 201, Seattle, WA
98103
United States
AU: McKenzie, D
EM: donaldmckenzie@fs.fed.us
AF: USDA Forest Service, Pacific Northwest Research Station, 400 N. 34th Street, Suite 201, Seattle, WA
98103
United States
AU: Littell, J
EM: jlittell@u.washington.edu
AF: College of Forest Resources, University of Washington, Box 352100, Seattle, WA 98195
United States
AB:
A warmer climate in western North America will first affect those forests that are most susceptible to soil moisture stress.
Increased water deficit will accelerate the normal stress complex experienced in forests, which typically involves some
combination of multi-year drought, insects, and fire. Symptoms of prolonged drought and insects are currently manifested in
extensive dieback of pine species in the pinyon-juniper forest of the American Southwest, an area where only a few tree
species can survive. Less severe dieback has occurred in mixed conifer forests of the Sierra Nevada, an area also subjected
to air pollution stress. Bark beetles are proliferating and killing millions of hectares of dry forest in the northern
interior of western North America, setting up the prospect of large and intense fires. Recent analyses of area burned by
fire in the 11 large Western states of the conterminous United States indicate that fire area will be at least twice as high
in the warmer climate predicted by general circulation models. Such a large increase in disturbance superimposed on forests
with increased stress from drought and insects may have significant effects on growth, regeneration, and long-term
distribution and abundance of forest species.
DE: 1630 Impacts of global change (1225)
SC: Global Climate Change [GC]
MN: Fall Meeting 2005