Lowland plant arrival in alpine ecosystems facilitates a decrease in soil carbon content under experimental climate warming

  1. Tom WN Walker  Is a corresponding author
  2. Konstantin Gavazov
  3. Thomas Guillaume
  4. Thibault Lambert
  5. Pierre Mariotte
  6. Devin Routh
  7. Constant Signarbieux
  8. Sebastián Block
  9. Tamara Münkemüller
  10. Hanna Nomoto
  11. Thomas W Crowther
  12. Andreas Richter
  13. Alexandre Buttler
  14. Jake Alexander
  1. ETH Zürich, Switzerland
  2. Swiss Federal Institute for Forest, Snow and Landscape Research, Switzerland
  3. Agroscope, Switzerland
  4. Université de Lausanne, Switzerland
  5. Princeton University, United States
  6. Université Grenoble Alpes, France
  7. University of Vienna, Austria
  8. École Polytechnique Fédérale de Lausanne, Switzerland

Abstract

Climate warming is releasing carbon from soils around the world1-3, constituting a positive climate feedback. Warming is also causing species to expand their ranges into new ecosystems4-9. Yet, in most ecosystems, whether range expanding species will amplify or buffer expected soil carbon loss is unknown10. Here we used two whole-community transplant experiments and a follow-up glasshouse experiment to determine whether the establishment of herbaceous lowland plants in alpine ecosystems influences soil carbon content under warming. We found that warming (transplantation to low elevation) led to a negligible decrease in alpine soil carbon content, but its effects became significant and 52% ± 31% (mean ± 95% CIs) larger after lowland plants were introduced at low density into the ecosystem. We present evidence that decreases in soil carbon content likely occurred via lowland plants increasing rates of root exudation, soil microbial respiration and CO2 release under warming. Our findings suggest that warming-induced range expansions of herbaceous plants have the potential to alter climate feedbacks from this system, and that plant range expansions among herbaceous communities may be an overlooked mediator of warming effects on carbon dynamics.

Data availability

Data Availability: All data contributing to the findings of this study have been deposited in the OSF under the DOI 10.17605/OSF.IO/S54CH. All R scripts necessary to reproduce the findings of this study are available in the github repository tom-n-walker/uphill-plants-soil-carbon.

The following data sets were generated

Article and author information

Author details

  1. Tom WN Walker

    Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
    For correspondence
    thomas.walker@unine.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8095-6026
  2. Konstantin Gavazov

    Swiss Federal Institute for Forest, Snow and Landscape Research, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4479-7202
  3. Thomas Guillaume

    Field-Crop Systems and Plant Nutrition, Agroscope, Changins, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  4. Thibault Lambert

    Faculty of Geosciences and the Environment, Université de Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  5. Pierre Mariotte

    Field-Crop Systems and Plant Nutrition, Agroscope, Changins, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8570-8742
  6. Devin Routh

    Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  7. Constant Signarbieux

    Swiss Federal Institute for Forest, Snow and Landscape Research, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  8. Sebastián Block

    Department of Ecology and Evolutionary Biology, Princeton University, Princeton, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Tamara Münkemüller

    Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  10. Hanna Nomoto

    Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  11. Thomas W Crowther

    Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  12. Andreas Richter

    Centre of Microbiology & Environmental Systems, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  13. Alexandre Buttler

    École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  14. Jake Alexander

    Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

Funding

European Union Horizon 2020 (678841)

  • Jake Alexander

Swiss National Science Foundation (31003A-176044)

  • Tom WN Walker
  • Jake Alexander

Swiss National Science Foundation (PZ00P2-174047)

  • Konstantin Gavazov

Swiss National Science Foundation (31003A-173210)

  • Sebastián Block

French National Research Agency (ANR-20-CE02-0021)

  • Tamara Münkemüller

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Bernhard Schmid, University of Zurich, Switzerland

Publication history

  1. Preprint posted: July 22, 2021 (view preprint)
  2. Received: March 11, 2022
  3. Accepted: May 6, 2022
  4. Accepted Manuscript published: May 12, 2022 (version 1)
  5. Version of Record published: June 13, 2022 (version 2)

Copyright

© 2022, Walker 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. Tom WN Walker
  2. Konstantin Gavazov
  3. Thomas Guillaume
  4. Thibault Lambert
  5. Pierre Mariotte
  6. Devin Routh
  7. Constant Signarbieux
  8. Sebastián Block
  9. Tamara Münkemüller
  10. Hanna Nomoto
  11. Thomas W Crowther
  12. Andreas Richter
  13. Alexandre Buttler
  14. Jake Alexander
(2022)
Lowland plant arrival in alpine ecosystems facilitates a decrease in soil carbon content under experimental climate warming
eLife 11:e78555.
https://doi.org/10.7554/eLife.78555
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