Similar to foresters, elephants thin the forest and ensure that the preferred species can grow better. This is the conclusion of researchers at the University of Saint Louis, in the US state of Missouri. According to them, animals play a key role in creating forests that store more atmospheric carbon and thus maintain biodiversity in the rainforests of Africa. If critically endangered elephants went extinct, the world’s second-largest rainforest would lose between 6% and 9% of its ability to sequester carbon, adding to global warming.
“Humans have hunted elephants for thousands of years. As a result, African forest elephants are critically endangered,” says lead author Stephen Blake of the University of Saint Louis. The biologist hopes that its importance for climate protection can be his salvation.
In the forest, some trees have light wood – low carbon density trees – while others produce heavy wood (high carbon density trees). Low carbon trees grow quickly and rise above other plants and trees to reach sunlight. Trees with a high carbon density, on the other hand, grow slowly, need less sunlight, and can also grow in shade. Elephants and other megaherbivores affect the population of these trees by feeding more on plants with low carbon density, which are more tasty and nutritious than other species, explain the researchers in the journal Proceedings of the National Academy of Sciences (Pnas) published study.
The forest is thinned
This thins out the forest, which encourages the growth of preferred species. This thinning reduces competition between trees and provides more light, space and nutrients to the soil to help carbon-rich trees thrive.
“Elephants eat a lot of leaves from a lot of trees and do a lot of damage in doing so,” Blake said. “They rip leaves off trees, rip whole branches or uproot young trees. But our data shows that most of this damage occurs in trees with a low carbon density. If you have a lot of trees with a high carbon density, there’s one less competitor. than being eliminated by the elephants.”