There are dire consequences to leaving elephant populations unprotected.
As megaherbivores, forest elephants have a significant effect on the environment around them. According to new research, their impact also extends to tree populations and carbon levels in the forest.
Up to now the significance of these ecosystem engineers’ dining habits on the carbon stocks in Africa’s rainforests remained largely unknown.
A new study found that in a less dense forest due to the presence of elephants will lead to changes in the competition for light, water and space among trees thereby affecting carbon levels which will have significant implications for climate and conservation policies.
In a paper recently published in Nature Geoscience, a Saint Louis University biologist, Stephen Blake, and his colleagues found that elephant populations in central African forests encourage the growth of slow-growing trees with a high wood density that sequesters more carbon from the atmosphere than fast-growing species which are the preferred foods of elephants.
It is likely that the presence of forest elephants may have shaped the structure of Africa’s rainforests, differentiating them from Amazonian rainforests.
An environmental advantage
These megaherbivores shape their environment by serving as seed dispersers and forest bulldozers as they eat over a hundred species of fruit, trample bushes, knock over trees and create trails and clearings.
Their ecological impact also affects tree populations and carbon levels in the forest, researchers report, with significant implications for climate and conservation policies.
The loss of elephants will seriously reduce the ability of the remaining forest to sequester carbon. Trees and plants use carbon dioxide during photosynthesis, removing it from the atmosphere. For this reason, plants are helpful in combating global warming and serve to store carbon emissions.
“Lo and behold, as we look at numbers of elephants in a forest and we look at the composition of forest over time, we find that the proportion of trees with high-density wood is higher in forests with elephants,” -Stephen Blake, Ph.D.
Without the forest elephants, less carbon dioxide will be taken out of the atmosphere. In monetary terms, forest elephants represent a carbon storage service of $43 billion.
Key Take-aways
- Researchers asked ‘What would happen to the composition of the forest over time with and without elephants?’
- They found that elephant browsing on fast-growing tree species damages and kills young plants which push the composition of the forest towards slow-growing plant species which increase in abundance in areas where elephants occur. Slow-growing plants have dense wood and therefore store more carbon than slow-growing species.
- The loss of elephants will seriously reduce the ability of the forest to sequester carbon and so less carbon dioxide will be kept out of the atmosphere.
- Elephants are a flagship species. People love elephants – we spend millions every year on cuddly toys, they are zoo favourites and who didn’t cry during Dumbo? and yet we’re pushing them closer to extinction every day. On the one hand, we admire them and feel empathy and are horrified when they are murdered and on the other hand, we’re not prepared to do anything serious about it. The consequences may be severe for us all. We need to change our ways.
“Besides, it just makes good sense to keep them around. They’re doing an amazing job of helping the planet store carbon for free.”
Sources:
