Tropical land use alters functional diversity of soil food webs and leads to monopolization of the detrital energy channel

  1. Peter Dietrich  Is a corresponding author
  2. Jens Schumacher
  3. Nico Eisenhauer
  4. Christiane Roscher
  1. Helmholtz Centre for Environmental Research, Germany
  2. Friedrich Schiller University Jena, Germany
  3. 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

The following data sets were generated

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Author details

  1. Peter Dietrich

    Department of Physiological Diversity, Helmholtz Centre for Environmental Research, Leipzig, Germany
    For correspondence
    peter.dietrich@idiv.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7742-6064
  2. Jens Schumacher

    Institute of Mathematics, Friedrich Schiller University Jena, Jena, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Nico Eisenhauer

    Experimental Interaction Ecology, German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig,, Leipzig, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0371-6720
  4. Christiane Roscher

    Department of Physiological Diversity, Helmholtz Centre for Environmental Research, Leipzig, Germany
    Competing interests
    The authors declare that no competing interests exist.

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.

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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  1. Peter Dietrich
  2. Jens Schumacher
  3. Nico Eisenhauer
  4. Christiane Roscher
(2022)
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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https://doi.org/10.7554/eLife.74054

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