Lowland plant arrival in alpine ecosystems facilitates a decrease in soil carbon content under experimental climate warming
- ETH Zürich, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research, Switzerland
- Agroscope, Switzerland
- Université de Lausanne, Switzerland
- Princeton University, United States
- Université Grenoble Alpes, France
- University of Vienna, Austria
- 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.
Article and author information
Author details
Konstantin Gavazov
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.
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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