Every day, new areas of rainforests are converted into plantations, drastically changing tropical biodiversity and the way the ecosystem functions.
Every day, new areas of rainforests are converted into plantations, drastically changing tropical biodiversity and the way the ecosystem functions. Yet, the current understanding of the consequences is fragmentary: previous studies tended to examine either biodiversity or the ecosystem. An international research team led by the universities of Göttingen in Germany and Bogor in Indonesia brings these threads together in this study. They analysed organisms ranging from microscopic mites and earthworms in the soil, to beetles and birds in tree canopies, comparing tropical rainforest with rubber and oil palm plantations in Sumatra, Indonesia. Their findings provide the first insights into the processing of energy across soil and canopy animal communities in mega-biodiverse tropical ecosystems. The researchers demonstrate that the conversion of rainforest into plantations erodes and restructures food webs and fundamentally changes the way they function. The results were published in Nature.
The researchers set out to study both biodiversity – plants, insects, vertebrates – and changes in how food webs function – biomass, trophic structure, energy fluxes. To do this, they estimated the abundance and biomass of the following: arthropods (such as spiders, insects, mites and centipedes) in the tree canopies using a technique known as “fogging”; birds using audio recorders and observation at specific points; and soil arthropods and earthworms from soil cores. This information was collected across 32 sites representing rainforest or plantations. They analysed their findings using existing models on traits and feeding preferences to reconstruct food webs at each site and across all animal groups. The results were used as measures of the distribution of energy and consumption of different resources (living plants, litter, bacteria, fungi, soil organic matter, other animals) in food webs above and below the ground. This method takes into account decomposition and quantifies the actions of predators (such as certain spiders or birds) in food webs.
Read more at University of Göttingen
Image: Rainforest (left) and oil palm plantation (right). Photo credit: Ananggadipa Raswanto via University of Göttingen
