Rainforest conversion to plantations fundamentally alters energy fluxes and functions in canopy arthropod food webs

Tropical rainforests around the world are rapidly being converted into cash crop agricultural systems. The associated massive losses of plant and animal species lead to changes in arthropod food webs and the energy fluxes therein. These changes are poorly understood, in particular in the extremely biodiverse canopies of tropical ecosystems. Using canopy fogging followed by stable isotope and energy flux analyses, we show that land-use conversion from rainforest to rubber and oil palm plantations not only causes a drastic reduction in energy fluxes of up to 75%, but also shifts fluxes among trophic groups. While rainforest featured high levels of both herbivory and algae-microbivory, and a balanced ratio of herbivory to predation, relative fluxes were shifted towards predation in rubber and towards herbivory in oil palm plantations, indicating profound shifts in ecosystem functioning. Our results highlight that the ongoing loss of animal biodiversity and biomass in tropical canopies degrades animal-driven functions and restructures canopy food webs.

Automated summary

Tropical rainforests are turning into cash crop agricultural systems, leading to massive losses of plant and animal species and changes in arthropod food webs and energy fluxes. Conversion to rubber and oil palm plantations results in a significant reduction in energy fluxes and shifts in trophic groups. These changes highlight the degradation of animal-driven functions and restructuring of canopy food webs.