Canadian Forest Service Publications
Changes in mean forest age in Canada’s forests could limit future increase in area burned but compromise potential harvestable conifer volumes. 2017. Boulanger, Y.; Girardin, M.; Bernier, P.; Gauthier, S.; Beaudoin, A.; Guindon, L. Can. J. For. Res. 47: 755-764.
Issued by: Laurentian Forestry Centre
Catalog ID: 37890
Availability: PDF (request by e-mail)
Forest fire activity is projected to increase with climate change in Canada, but vegetation feedbacks are usually not considered. Using new information on selectivity or avoidance of fire related to stand age and composition, we ran simple simulation models that consider changes in the regional age matrices induced by fire and harvesting to project future burn rates. We also projected estimated future regional vulnerability of timber supply to fire by considering these new burn rates. The inclusion of age-related feedbacks would have a large impact on projected increases in burn rates, mostly in very fire active zone under aggressive climate forcing. Projected burn rates would still increase, but would be 50% less in 2100 than if projected without this biotic feedback in some zones. Negative feedbacks would be virtually non-existent when potential burning rates are below 1%, whereas realized burning rates would be lowered by more than 0.5% percentage points when potential burning rates exceed 2.5%. Including fire-vegetation feedbacks had virtually no impact on total volume harvested. As fire burn more old-growth coniferous stands, slightly negative impacts were projected on conifer harvested almost everywhere. These results underline the need to incorporate vegetation – fire feedbacks when projecting future burn rates.
Plain Language Summary
In this study, the researchers factored the impact of forest fires on vegetation composition into projection models of burned forest areas. The results showed that when this impact is taken into account, projections of burned areas in high-risk zones decrease by 50% compared with projections made without factoring in this variable. Since fires tend to affect old conifer stands more severely, these stands are less available for logging.
The researchers predict that climate change is likely to cause a rise in forest fires across Canada. The results of this study show how important it is to take into account the impact of fire on vegetation when using fire prediction models.