D. Boychuk et Ah. Perera, MODELING TEMPORAL VARIABILITY OF BOREAL LANDSCAPE AGE-CLASSES UNDER DIFFERENT FIRE DISTURBANCE REGIMES AND SPATIAL SCALES, Canadian journal of forest research, 27(7), 1997, pp. 1083-1094
Natural fire disturbances are known to have had a significant role in
boreal forests at the stand and landscape levels. Van Wagner's exponen
tial model gave useful insight into the theoretical dynamics of the fo
rest age distribution in fire-disturbed landscapes. His work motivated
extensions to the theoretical model and more empirical tests in a var
iety of landscapes. The empirical tests have had mixed results. While
Van Wagner stated that the model is theoretical, and warned that one s
hould expect to fmd variability in landscapes in any case, there is th
e risk that the exponential model can be misunderstood or inappropriat
ely applied if variability is not adequately considered. An existing t
heoretical simulation model of landscape fire disturbance (FLAP-X) was
used to explore the temporal variability of two selected landscape at
tributes: the percentages of old growth and recently disturbed area. I
t was found that under characteristic boreal fire disturbance regimes,
these percentages can vary widely over time even at large spatial sca
les due to the spatiotemporal autocorrelation of disturbances. Some of
the consequent implications of managing a landscape for naturalness a
t multiple spatial scales when there is a wide range of conditions tha
t can be considered natural are discussed.