EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Nutrient scarcity strengthens soil fauna control over leaf litter decomposition in tropical rainforests

Guille Peguero1, Jordi Sardans1, Andreas Richter2, Ivan Janssens3, and Josep Peñuelas1
Guille Peguero et al.
  • 1CREAF, Global Ecology Unit, Spain (
  • 2University of Vienna, Department of Microbiology and Ecosystem Science
  • 3University of Antwerp, Centre of Excellence PLECO (Plants and Ecosystems), Department of Biology

Soil fauna is a key control of the decomposition rate of leaf litter, yet its interactions with litter quality and the soil environment remain elusive. We conducted a litter decomposition experiment across different topographic levels within the landscape replicated in two rainforest sites providing natural gradients in soil fertility to test the hypothesis that low nutrient availability in litter and soil increases the strength of fauna control over litter decomposition. We crossed these data with a large dataset of 44 variables characterizing the biotic and abiotic microenvironment of each sampling point and found that microbe-driven Carbon (C) and Nitrogen (N) losses from leaf litter were 10.1 and 17.9 % lower, respectively, in the nutrient-poorest site but this among-site difference was equalized when meso- and macrofauna had access to the litterbags. Further, on average soil fauna enhanced the rate of litter decomposition by 22.6%, and this contribution consistently increased as nutrient availability in the microenvironment declined. Our results indicate that nutrient scarcity increases the importance of soil fauna on C and N cycling in tropical rainforests. Further, soil fauna is able to equalize differences in microbial decomposition potential thus buffering to a remarkable extent nutrient shortages at an ecosystem level.

How to cite: Peguero, G., Sardans, J., Richter, A., Janssens, I., and Peñuelas, J.: Nutrient scarcity strengthens soil fauna control over leaf litter decomposition in tropical rainforests, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-747,, 2022.