Document: CHA-3-69-38
Interspecific variation in susceptibility to windthrow as a function of tree size and storm severity for northern temperate tree species.
CANHAM, C.D.* 1, M.J.PAPAIK 1 and E.F.LATTY 1,2
Institute of Ecosystem Studies, Millbrook, NY 12545, USA 1
Cornell University, Ithaca, NY, USA 2
Abstract:
Studies of the effects of wind disturbance on forests typically focus on the most severe, catastrophic disturbances; however, it is clear that wind disturbance regimes are characterized by events with a wide range of severity. Studies of these intermediate-intensity events have been hampered by the lack of methods to quantify variation in both storm severity and the responses of dominant tree species to winds of varying intensity. We report here the development of a new, empirical method of simultaneously estimating both local storm severity and the parameters of functions that define species-specific variation in susceptibility to windthrow as a function of storm severity and tree size. We tested the method using data collected following a severe storm that struck the western Adirondack Mountains of New York in 1995. That region contains one of the largest remaining tracts of old growth forest in the northeastern U.S., and our analyses allowed us to also examine differences in susceptibility to windthrow in old growth versus second growth forests. Our results highlight significant variation among tree species in both their susceptibility to windthrow across a gradient in storm severity, and variation in susceptibility to windthrow as a function of tree size and the successional status of the stand. Our results suggest that some of the distinctive features of old growth forests in the region may be due to variation among trees in their ability to survive disturbance events that vary widely in intensity.
Keywords: susceptibility to windthrow, maximum-likelihood methods, windstorm intensity
This abstract is being presented at: 10:30 AM in session:
Oral Session #42: Disturbance Ecology: Effects of Storms.