PARIS: African elephants are under threat. In the space of three decades, their population has fallen by more than 80%. It’s a worrying decline, mainly linked to the intensive poaching that is rampant in this region of the world.
But the extinction of this species could also have direct consequences on global warming and, more precisely, on the ability of forests to absorb and store carbon, according to research published in the journal “PNAS”.
Conducted by researchers from Saint Louis University in the United States, in collaboration with France’s National Center for Scientific Research, the paper highlights the impact that the disappearance of elephants could have on the forests of the Congo Basin and West Africa.
According to their estimates, the world’s second-largest rainforest could lose between 6% and 9% of its carbon-storage capacity.
There are two main reasons for this. First, African elephants feed almost exclusively on vegetation and, given their size, do not hesitate to strip branches and uproot young trees to feed.
This mode of feeding allows for the regulation of forest ecosystems, notably favouring growth conditions for high-carbon-density trees by thinning out low-carbon-density species.
“Our data shows most of this damage [caused by elephants eating] occurs to low-carbon-density trees. If there are a lot of high-carbon-density trees around, that’s one less competitor, eliminated by the elephants,” the paper’s senior author, Stephen Blake, said.
The second reason that global warming may be exacerbated is that elephants spread, through their droppings, undamaged seeds that are ready to germinate, which can give rise to the largest trees in the forest.
“These results demonstrate the importance of megaherbivores for maintaining diverse, high-carbon tropical forests. Successful elephant conservation will contribute to climate mitigation at a globally relevant scale,” conclude the authors.
The scientists now plan to conduct further research to assess the ecological impact of other animals on tropical forest biodiversity.
“The implications of our study extend beyond just forest elephants in Africa,” explains lead author Fabio Berzaghi.
“As we show that leaves from low-carbon-density trees are less palatable to herbivores, those findings imply that other large herbivores, such as primates or the Asian elephant, could also contribute to the growth of high-carbon-density trees in other tropical forests.
“Our aim is to expand on this by investigating those other species and regions.”