Tropical land use alters functional diversity of soil food webs and leads to monopolization of the detrital energy channel
- Helmholtz Centre for Environmental Research, Germany
- Friedrich Schiller University Jena, Germany
- German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig,, Germany
Abstract
Agricultural expansion is among the main threats to biodiversity and functions of tropical ecosystems. It has been shown that conversion of rainforest into plantations erodes biodiversity, but further consequences for food-web structure and energetics of belowground communities remains little explored. We used a unique combination of stable isotope analysis and food web energetics to analyze in a comprehensive way consequences of the conversion of rainforest into oil palm and rubber plantations on the structure of and channeling of energy through soil animal food webs in Sumatra, Indonesia. Across the 23 animal groups studied, most of the taxa switched to freshly-fixed plant carbon (low Δ13C values) indicating 'fast' energy channeling in plantations as opposed to 'slow' energy channeling through the detrital pathway in rainforests (high Δ13C values). These shifts led to changes in isotopic divergence, dispersion, evenness and uniqueness. However, earthworms as major detritivores stayed unchanged in their trophic niche and monopolized the detrital pathway in plantations, resulting in similar energetic metrics across land-use systems. Functional diversity metrics of soil food webs were associated with reduced amount of litter, tree density and species richness in plantations, providing guidelines how to improve the complexity of the structure of and channeling of energy through soil food webs. Our results highlight the strong restructuring of soil food webs with the conversion of rainforest into plantations threatening soil functioning and ecosystem stability in the long term.
Data availability
The data reported in this paper have been deposited in Dryad, whichcan be publicly accessed at https://doi.org/10.5061/dryad.gmsbcc2p7
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Eco-evolutionary feedbacks modulate plant responses to global change depending on plant diversity and species identityDryad Digital Repository, doi:10.5061/dryad.gmsbcc2p7.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (FOR 1451; FOR 5000; FZT 118)
- Nico Eisenhauer
- Christiane Roscher
Heinrich Böll Stiftung (Ph.D. scholarship)
- Peter Dietrich
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- David A. Donoso, Escuela Politécnica Nacional, Ecuador
Version history
- Received: September 20, 2021
- Preprint posted: October 8, 2021 (view preprint)
- Accepted: March 29, 2022
- Accepted Manuscript published: March 30, 2022 (version 1)
- Accepted Manuscript updated: March 31, 2022 (version 2)
- Version of Record published: May 16, 2022 (version 3)
Copyright
© 2022, Dietrich et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Tropical land use alters functional diversity of soil food webs and leads to monopolization of the detrital energy channel
eLife 11:e74054.
https://doi.org/10.7554/eLife.74054
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