Palm oil plantations have an overall negative impact on biodiversity, according to research released this week. The study, published in Nature Communications, found palm oil plantations are home to fewer insect species than even intensive rubber tree plantations.
A forests expert at James Cook University, Bill Laurance, said of the research:
“The big message is that oil palm is bad for biodiversity, in every sense of the word — even when compared to damaged rainforests that are regenerating after earlier logging or clearing.”Professor Bill Laurance, James Cook University.
The study, conducted in Sumatra – an Indonesian island famous for its tiger and orangutan populations – found that palm oil plantations contain half the number of insect species that natural forests do.
Research from @uniGoettingen shows #palmoil plantations are bad for wildlife great and small. You can help them with a #Boycott4Wildlife of supermarket brands destroying the world.Tweet
We analyse consequences of the globally important land-use transformation from tropical forests to oil palm plantations. Species diversity, density and biomass of invertebrate communities suffer at least 45% decreases from rainforest to oil palm.Barnes, A., Jochum, M., Mumme, S. et al. Consequences of tropical land use for multitrophic biodiversity and ecosystem functioning. Nat Commun 5, 5351 (2014). https://doi.org/10.1038/ncomms6351
Worldwide, palm oil is one of the most rapidly expanding crops, with the total area of land devoted to palm oil production tripling in the last 25 years. This expansion has been blamed for the rapid deforestation seen in both Indonesia and Malaysia in recent years.
In Sumatra, roughly 25% of palm oil plantations have been directly converted from forest. Still, Indonesia – one of the world’s leading palm oil producers — plans to double palm oil production by 2020.
The environmental and social consequences of palm oil production have been hotly debated over the past decade, particularly due to the industry’s impact on orangutans.
A decline in predatory insects — which help keep other species under control — was particularly worrying.
“This is analogous to the kinds of changes we see in larger animals, such as birds and mammals. The specialists and bigger predators tend to be highly vulnerable, and they’re often replaced by generalist omnivores in disturbed environments.
“For example, you lose tigers and specialised understory birds and gain ‘trash’ species—such as generalist rats—that can live almost anywhere.”
Read about the disappearing creatures of palm oil deforestation
Insects are important in ecosystems because they help recycle nutrients, and are a food source for other species.
The new research shows a clear link between the reduced numbers of species in palm oil plantations, and lower energy transfer and ecosystem function in these regions.
This is bad news for other species that live in the region, such as the orang-utan: if the environment is producing less energy, it will be harder to survive.
Head of the Conservation Biology department at the University of Göttingen, Germany, and one of the paper’s authors, Ulrich Brose, said there could be several reasons for the loss of insects.
“Two potential explanations are the pesticides or insecticides applied at higher levels in oil palm plantations or differences in energy (litter or nutrients) input.”
He said their data couldn’t yet disentangle these causes, however the research team at the University of Göttingen were working towards an answer.
Samantha Walker, Editor, The Conversation