In France, two thirds of the water tables are at a low or very low level and 20 departments are already experiencing restrictions on water use. In the eastern Pyrenees, on the border with Spain, the situation is already critical and is affecting human activities and nature. While this Monday, May 22 marks the International Day of Biodiversity, the Albères massif, where the Massane forest is located, a nature reserve classified as a UNESCO World Heritage Site, has been suffering from a lack of water for months.
With our special correspondent in Argelès-sur-Mer, Lucile Gimberg
Dropping leaves to sweat less, sacrificing certain branches: trees multiply strategies to survive the lack of water. But on the Albères massif, in the Eastern Pyrenees, droughts and heat waves have followed one another for several years due to climate change. And now, even Mediterranean species such as cork oak or holm oak are withering away.
“The problem is that there, they have been dropping the leaves several times, they have no more reserves and they end up drying up.explains Joseph Garrigue, curator of the Massane nature reserve for 30 years. As there is no more water, they are unable to raise the sap to the top and so we see what are called descents of the tops, the tree goes down, it goes down, then it ends by dying. »
Along the track, the junipers are withered and the pink flowers of the cottony cistus are half their normal size. The whole food chain is disrupted: “ For example, the little caterpillars of butterflies in fact, they will not be able to ensure their complete development cycle, the caterpillar will come out, and then it will start to eat its high plant, but the high plant will dry up before the caterpillar has reaches the stage where it can metamorphose into a butterfly, and therefore there will be no butterfly. This goes for other insects, if there are no butterflies, the birds won’t have any butterflies to eat and so it’s all cascading. »
A hope all the same for the scientist: that the majestic beech trees of the Massane forest, at the top of the massif, will survive the warming temperatures. At least in a few pockets of resistance near the river, as they did during the Ice Age.
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