Abstract
Woody plants (shrubs and trees) are encroaching across the globe, affecting livestock production and terrestrial ecosystem functioning. Despite the widespread practice, there has been no quantitative global assessment of whether removal of encroaching woody plants will re-instate productive grasslands and open savanna. Here we compiled a global database of 12,198 records from 524 studies on the ecosystem responses of both the encroachment and removal of woody plants, and show that removal fails to reverse encroachment impacts. Removing woody plants only reversed less than half of the reductions in herbaceous structure induced by encroachment, and woody expansion actually enhanced ecosystem functions (+8%). The effectiveness of removal varied with encroachment stage (that is, time since treatment) and the functional traits (for example, deciduousness and resprouting) of the focal woody species, and waned in drier regions. Our results suggest that assessment of woody plant communities before removal is critical to assess the likelihood of successful ecosystem recovery.
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Data availability
All the materials, raw data and protocols used in the article are available upon request and without restriction. The meta-analysis database is available in figshare repository (https://doi.org/10.6084/m9.figshare.19915300.v2). Source data are provided with this paper.
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Acknowledgements
We thank B. Fu and S. Soliveres for their valuable comments on the original draft, S. Nakagawa and M. Mallen-Cooper for assistance with the meta-analysis, and M. GarcÃa Criado for constructive comments during the peer review process. This research is funded by the Third Xinjiang Scientific Expedition Program (grant no. 2022xjkk0405 to J.D.), National Natural Science Foundation of China Project (grant nos. 32201324 and 41991232 to J.D.), the Fundamental Research Funds for the Central Universities (to J.D.), State Key Laboratory of Earth Surface Processes and Resource Ecology (2022-TS-02 to J.D.) and the Hermon Slade Foundation (to D.E.).
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D.E. and J.D. designed the research, collected data and built the databases. J.D. performed the statistical analyses and wrote the first draft. D.E. critically revised the manuscript.
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Nature Plants thanks Zhengbing Yan and Mariana GarcÃa Criado for their contribution to the peer review of this work.
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Ding, J., Eldridge, D. The success of woody plant removal depends on encroachment stage and plant traits. Nat. Plants 9, 58â67 (2023). https://doi.org/10.1038/s41477-022-01307-7
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DOI: https://doi.org/10.1038/s41477-022-01307-7
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