Can a fire occur twice in the same place?
“A fire can very well burn where it has already burned, especially at this time”, answers the prevention coordinator of the Society for the protection of forests against fire (SOPFEU), Stéphane Caron. “In a fire, not all areas are completely burned, so it can easily resume. It should be understood that on a fire that has already burned, the territory becomes drier, so what has not passed through the fire is already dried out to an extreme level. In other words, it is highly flammable, a forest sector that has just burned,” he explains.
Is it frequent?
In normal times, it is rather rare to see fires return to the same place in a short time, but with the current conditions, “the drought is accumulating and it is becoming more favorable”, notes Mr. Caron. Thus, even if a fire is theoretically stopped, several hot spots are “just waiting to be woken up”, he illustrates. “It means that any fire can regain strength and even start to progress again. We really have a perfect weather cocktail for the progression of the fires this week. »
Are successive fires worse for fauna and flora?
Two close fires can have a considerable impact on an ecosystem, says Daniel Kneeshaw, holder of the Research Chair in the Resilience and Vulnerability of Temperate and Boreal Forests to Climate Change at the University of Quebec in Montreal (UQAM).
“If it happens twice before the trees reach a certain mature age, by then they won’t have produced seeds on the ground for it to regrow. This would then result in us ending up with areas without trees in the long term, or more with a type of herbaceous vegetation that dominates. We would therefore lose a lot of forest land in the long term,” worries Mr. Kneeshaw.
There would also be an issue for certain animal species, especially birds, which “need closed forests to live”, says the expert. “There is no shortage of open spaces in Quebec, but the loss of closed forests would be harmful in the long term for several species whose habitat it is. »
Is replanting worth it?
According to Daniel Kneeshaw, the impact of the multiplication of fires will also necessarily be felt on long-term forest production in Quebec. “It risks putting pressure on the wood that remains elsewhere, which has not burned, in other words. We could even possibly envisage a shortage of equipment, and therefore of jobs, in regions where the industry would be weakened, ”he recalls.
The essential question to ask, insists the teacher, “is that if we plant, will the trees reach maturity before the next fire”? If Quebec needs to plant more, “more roads will have to be built to do so, which will inevitably also increase costs,” he notes.
“It basically comes down to whether the investment is worth it without some form of natural regeneration. We should at least question ourselves, have a serious debate on this in terms of budgets, ”said Mr. Kneeshaw.
Should we review our rate of cuts?
“Regeneration accidents”, i.e. episodes where portions of the forest are unable to grow back, are also likely to worsen, warns Philippe Gachon, professor of geography and specialist in forest fires. “When this is combined with logging, we can already see it in certain regions of Quebec, there is simply nothing left to grow. The floor is completely stripped. This is a major problem that we are also experiencing in Quebec, ”he analyzes.
For him, “we will above all have to review our supply and cost strategy, because the forest will not be able to regenerate if we maintain the cutting rates we have today”. “It is no longer adapted to the changing conditions and the cycles of forest fires which are taking on enormous proportions, precisely,” insists Mr. Gachon.
To protect cities and infrastructures, the work of firefighters is essential, notes Mr. Kneeshaw, but their efforts cannot really change the situation at the point where the situation is today. “For most of the work, it’s really Mrs. Weather who determines what happens next. When the fire is big, there is no absolute control you can have over the territory. We then limit ourselves to protecting our assets, such as power transmission lines, for example,” he concludes.