Precipitation increase promotes soil organic carbon formation and stability via the mycorrhizal fungal pathway

Changes in soil organic carbon (SOC) stocks play a pivotal role in regulating future climate change. Arbuscular mycorrhizal fungi (AMF) are critical regulators of SOC dynamics, yet the impacts of climate-induced changes, such as precipitation increase (Pi), on AMF- and root-mediated SOC formation and stability remain largely unexplored. Combining global meta-analysis with a long-term field experiment, our study demonstrates that Pi enhances SOC formation and stability primarily through AMF, rather than plant roots, by recruiting bacterial K-strategists and promoting necromass production. These findings provide direct evidence that AMF-driven microbial processes are essential for SOC stability under changing precipitation regimes, uncovering an often-overlooked mechanism of SOC sequestration in grassland ecosystems and enhancing our understanding of climate change impacts on C cycling.

土壤有机碳（soil organic carbon, SOC）储量的变化对未来气候变化的调控具有关键作用。丛枝菌根真菌（arbuscular mycorrhizal fungi, AMF）是调控土壤有机碳动态的核心因子，但气候诱导的环境变化（如降水增加（precipitation increase, Pi））对AMF与根系介导的土壤有机碳形成及稳定性的影响，目前仍未得到充分探明。本研究结合全球荟萃分析与长期野外试验，证实降水增加主要通过AMF（而非植物根系）促进土壤有机碳的形成与稳定性，其作用路径为招募细菌K-策略微生物并促进其残体生成。上述发现为降水格局改变背景下AMF驱动的微生物过程对土壤有机碳稳定性的必要性提供了直接证据，揭示了草原生态系统中常被忽略的土壤有机碳固存机制，并深化了我们对气候变化影响碳循环的认知。

搜集汇总

背景与挑战

背景概述

该数据集通过田间实验和元分析数据，研究了降水增加如何通过菌根真菌途径促进土壤有机碳的形成和稳定性，揭示了气候变化对碳循环的影响机制。