Summer is about to end in Europe and is about to return to Australia. But for the third consecutive year, the summer season will be marked by La Niña, a meteorological phenomenon that results in very heavy rainfall. After a year already marked by exceptional floods and floods, 2022 is already the wettest year in Australian history, and this new wave of bad weather could also cause the extinction of certain plant species, which are themselves crucial for the survival of many animals.
With our correspondent in Sydney, Gregory Plesse
The Sydney Botanical Garden is probably the only one in the world where the arrival of rain is feared. Because it is conducive, especially in periods of high heat, to the spread of a disease from South America that ravages dozens of endemic tree species.
The two previous summers, also very rainy like the one to come, have already had a very heavy impact, as Brett Summerell, scientific director of the Sydney Botanic Garden, recalls: “ These species of trees, for several years now, no longer flower and no longer produce seeds. So much so that we now have 16 tree species from tropical forests that are on the verge of extinction. »
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Seeds set aside
Since these trees are structural elements of certain ecosystems, their disappearance could also threaten part of the Australian fauna. ” If these tree species die, continues Brett Summerell, any animals that depend on it will either have to find a new food source, if one exists, or find a new habitat. This could therefore have a strong impact on these animals. And that includes koalas, bats, a very large number of bird species, but also many tiny insects. »
In the absence of being able to stop the rain, the researchers of the botanical garden put aside, as much as they can, seeds of these trees threatened with extinction, hoping that in the future, a cure for this disease will be found. who strikes them down.
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