A continental scale analysis reveals widespread root bimodality
An improved understanding of root vertical distribution is crucial for assessing plant-soil-atmosphere interactions and their influence on the land carbon sink. Here, we analyze a continental-scale dataset of fine roots reaching 2 meters depth, spanning from Alaskan tundra to Puerto Rican forests. Contrary to the expectation that fine root abundance decays exponentially with depth, we found root bimodality at ~20% of 44 sites, with secondary biomass peaks often below 1 m. Root bimodality was more likely in areas with low total fine root biomass and was more frequent in shrublands than grasslands. Notably, secondary peaks coincided with high soil nitrogen content at depth. Our analyses suggest that deep soil nutrients tend to be underexploited, while root bimodality offers plants a mechanism to tap into deep soil resources. Our findings add to the growing recognition that deep soil dynamics are systematically overlooked, and calls for more research attention to this deep frontier in the face of global environmental change.
Authors
- Samantha R. Weintraub (ORCID: https://orcid.org/0000-0003-4789-5086)
- Shersingh Joseph Tumber‐Dávila (ORCID: https://orcid.org/0000-0001-7336-3943)
- Xingchen Wang (ORCID: https://orcid.org/0000-0001-5316-789X)
- Robert B. Jackson (ORCID: https://orcid.org/0000-0001-8846-7147)
- Sili Wang (ORCID: https://orcid.org/0000-0002-4552-6984)
- Avni Malhotra (ORCID: https://orcid.org/0000-0002-7850-6402)
- Mingzhen Lu (ORCID: https://orcid.org/0000-0002-8707-8745)
- Michael McCormack (ORCID: https://orcid.org/0000-0002-8300-5215)
Institutions
- Boston College (US)
- Dartmouth College (US)
- Santa Fe Institute (US)
- Harvard University (US)
- Pacific Northwest National Laboratory (US)
- University of Zurich (CH)
- Morton Arboretum (US)
- National Ecological Observatory Network (US)
- Dana-Farber/Harvard Cancer Center (US)
- New York University (US)
- Columbia University (US)
- Stanford University (US)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-06-17
- DOI
- https://doi.org/10.1038/s41467-025-60055-2
- Citations
- 9
- Primary Topic
- Geology and Paleoclimatology Research
- Type
- article
- Field-Weighted Citation Impact
- 11.71
Funders
- National Science Foundation
- U.S. Department of Energy
- Battelle
- Santa Fe Institute
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Office of Science
- Biological and Environmental Research
- Pacific Northwest National Laboratory