Fire and the forest mosaic
As species succession continues with time after fire, composition of the forest
mosaic is greatly influenced by the forest fire frequency. Thus if fire frequency
is high, the landscape will be dominated by pioneer species, principally intolerant
hardwoods, whereas as fires become less frequent, later successional conifers
become more abundant. Figure 1 ( Bergeron et Dansereau, 1993) illustrates this
landscape-level change for increasingly longer fire cycles. The fire cycle
corresponds here to the time necessary to burn an area comparable to the Lake
Duparquet Forest.
The composition of the forest mosaic has an important
influence on the vulnerability of softwood stands to spruce budworm outbreaks
and could be determinant in the quality of certain wildlife habitat.
Fig. 1. Proportion of stand types for different fire cycles using the 1983
forest map.
|
|