California is still facing a large wildfire named “Oak Fire”, near Yosemite National Park, known for its gigantic redwoods. Nearly 7,500 hectares went up in smoke, and the firefighters are still mobilized to try to control the fire and avoid losing more hectares, as well as these veritable plant cathedrals. Why do these repeated fires threaten the region’s environment today more than yesterday?
It has been a week since the “Oak Fire” broke out, but it has already destroyed some 40 buildings, threatened several thousand homes in small rural towns in Mariposa County, in the foothills of the Sierra Nevada, and destroyed more than 7,500 hectares.
For the second time this year, a fire is therefore dangerously approaching Yosemite National Park, where redwoods have resided for some millennia. But this one is even more powerful than the previous one, although firefighters hope to overcome it thanks to recent progress in fighting the flames.
Sequoias increasingly threatened
The redwoods, threatened by the previous fire, had been generally preserved thanks in particular to controlled fires carried out for decades in these groves to reduce the fuel on the ground. However, this increase in the frequency of fires is not normal.
Our reporter Justine Fontaine contacted Andrea Williams of the California Native Plant Society, an American environmental NGO. She knows the flora of the region well, and for her, the evolution of human activities is responsible for the aggravation of the fires. ” Most plants in California have adapted over centuries to low-intensity fires. But over the past 200 years, the way the land has been managed has led to the increasingly frequent felling of large trees. Climate change has also had an impact, in the form of drought, which tends to make fires more severe. »
Over the past 200 years, the way the land has been managed has led to the increasingly frequent felling of large trees.
Andrea Williams, California Native Plant Society
Indeed, these upheavals have made the ecosystem as a whole more sensitive to flames. And last year, big trees in California suffered. ” This explains in particular the fact that very old redwoods burned last year during the great fires which affected California, which is unusual. Because these trees are generally well adapted to low intensity fires, to the point that in some cases they even need fire to reproduce. But the fact that such large trees are dying is a clear sign that there is an environmental imbalance. “Warns Andrea Williams.
The efforts of firefighters could be helped in the coming days by the arrival of the fire in an area already devastated in 2018 by another forest fire.
(And with AFP)
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