Root traits and mycorrhizal fungi mediate reactive N and warming impacts on soil organic carbon
Plant roots and arbuscular mycorrhizal fungi (AMF) form a ubiquitous symbiosis in terrestrial ecosystems and critically affect soil organic carbon (SOC) dynamics. However, how roots and AMF mediate the impact of reactive nitrogen (Nr) and climate warming on SOC remains unclear. Using a multi-year Nr addition and simulated warming experiment in a semi-arid grassland, we show that Nr input and warming alter SOC by reshaping plant communities and inducing multidimensional tradeoffs among fine-root traits and AMF communities. Stable isotope (<sup>13</sup>C) tracing revealed that Nr- and warming-induced changes in roots and AMF reduced C input belowground, and mineral-associated organic C and microbial necromass in soil, while stimulating organic C decomposition. Nr input also increased soil N:P ratios and shifted AMF communities toward taxa with finer extraradical hyphae, weakening SOC protection. Together, these findings highlight root-AMF interactions as critical regulators and improve predictions of long-term SOC dynamics under future climate change.
Authors
- Xinxin Cao
- Bianbian Wang
- Tongshuo Bai (ORCID: https://orcid.org/0009-0009-2815-1023)
- Ripley H. Tisdale (ORCID: https://orcid.org/0000-0002-3845-8784)
- Christopher J. Gillespie (ORCID: https://orcid.org/0000-0002-2636-6436)
- Xi Xu (ORCID: https://orcid.org/0000-0002-6319-8558)
- Kaiyun Qian (ORCID: https://orcid.org/0009-0006-7859-7216)
- Alex Woodley
- Yunfeng Zhao
- Lingli Liu
- Weixing Zhu
- Liang Guo
- Kangcheng Zhang
- Yi Wang
- Kevin Garcia
- Yexin Zhao
- Shuijin Hu
- Tangqing He
- Shuqi Wu
- Xiaodong Wang
- Yi Zhang
- Chenglong Ye
- Zhen Li
- Lijin Guo
Institutions
- Nanjing Agricultural University (CN)
- Binghamton University (US)
- United States Department of Agriculture (US)
- North Carolina State University (US)
- Sun Yat-sen University (CN)
- Chinese Academy of Sciences (CN)
- North Carolina Department of Agriculture and Consumer Services (US)
- Institute of Soil and Water Conservation (CN)
- Ministry of Water Resources of the People's Republic of China (CN)
- Institute of Botany (CN)
- Institute of Earth Environment (CN)
- University of Chinese Academy of Sciences (CN)
- Fujian Agriculture and Forestry University (CN)
- The University of Tokyo (JP)
- Northwest A&F University (CN)
Publication Details
- Journal
- Nature Communications
- Published
- 2026-02-25
- DOI
- https://doi.org/10.1038/s41467-026-69301-7
- Primary Topic
- Mycorrhizal Fungi and Plant Interactions
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Natural Science Foundation of China