THEORETICAL-ANALYSIS OF SWITCHING IN A LOCALIZED MODEL FOR MOUNTAIN PINE-BEETLE MASS ATTACK

Citation
J. Powell et al., THEORETICAL-ANALYSIS OF SWITCHING IN A LOCALIZED MODEL FOR MOUNTAIN PINE-BEETLE MASS ATTACK, Journal of theoretical biology, 194(1), 1998, pp. 49-63
Citations number
67
Categorie Soggetti
Biology,"Biology Miscellaneous
ISSN journal
00225193
Volume
194
Issue
1
Year of publication
1998
Pages
49 - 63
Database
ISI
SICI code
0022-5193(1998)194:1<49:TOSIAL>2.0.ZU;2-C
Abstract
The dynamic interaction between mountain pine beetles (MPB) and hosts (generally lodgepole pine) is reviewed briefly. In particular, success ful ''switching'' from initial foci of attack to nearby hosts which ma y be higher-quality resources is a potentially critical element initia ting the transition from endemic to epidemic population levels. A coup led partial differential equation model for MPB dispersal and host res ponse is reviewed. The equations are decoupled making an adiabatic ass umption for MPB chemotaxis, and a ''local'' projection is made using t he leading eigenfunction for the MPB density equation. This projection yields a system of ordinary differential equations for the spatio-tem poral responses at individual trees. These equations are analysed to d etermine what factors control successful ''switching'' in a two-tree m odel. The results suggest that stand thinning ameliorates outbreaks ma inly through interference with the chemical ecology via a change in mi cro-climate, rather than by altering host vigor. (C) 1998 Academic Pre ss.