AMF促进土壤有机碳固持的机理会随其多样性改变吗？

Arbuscular mycorrhizal fungi (AMF) is widely considered as an important regulator for soil carbon (C) pool. However, due to lack of researches on the coupling of AMF diversity and its ecological multifunction, the knowledge gap still exists on whether the role of AMF in mediating soil C storage will be altered by changes in AMF diversity. Based on our previous studies of mycorrhizae resources in evergreen broadleaf forests, we propose a hypothesis that AMF diversity affects its regulation on soil organic carbon (SOC) accumulation. Specifically, AMF diversity will be altered by the succession stages in evergreen broadleaf forests and the mechanism underlying the regulation of AMF on SOC accumulation will shift from biochemical driving to chemical and physical protection during forest succession. To test this hypothesis, we examine AMF diversity along succession stages in evergreen broadleaf forests and the possible ways of regulation of AMF on SOC accumulation, including biochemical, chemical, and physical paths. The ultimate goal of this project is to illuminate the tendency of AMF diversity along the process of succession in evergreen broadleaf forests, to reveal the relationship between AMF diversity and plant diversity, to establish theoretical model for the regulation of AMF on SOC accumulation. This project will provide synthetical methods for evaluating the influence of AMF on soil C cycling; it will also provide first hand data for understanding the above- and belowground relationship in evergreen broadleaf forests. In addition, it will provide information to refine current knowledge on ecological multifunction in evergreen broadleaf forests under global change.

丛枝菌根真菌（AMF）是土壤碳库重要的调节者。AMF多样性研究近年来取得重要进展，然而对其多样性和生态系统功能的耦合研究十分有限，学术界关于AMF多样性变化是否引起其生态功能改变尚无定论。本项目基于对常绿阔叶林菌根资源的研究基础，提出AMF促进土壤有机碳固持的机理随其多样性变化的假设：AMF多样性随植物多样性变化而变化，在群落演替过程中AMF对土壤有机碳固持的影响机理存在由生物化学过程主导向化学、物理过程为主的方式变迁。为验证该假设，项目以常绿阔叶林及其演替系列为研究对象，以AMF多样性为切入点，从生物化学、化学、物理途径定量研究AMF对土壤有机碳累积的影响，阐明AMF多样性的变化及其与植物物种多样性的关系，分析AMF促进土壤有机碳累积的机制，解答AMF促进土壤有机碳固持的机理是否会随其多样性而改变的问题。研究结果可为评估常绿阔叶林地上地下多样性关联和探讨AMF对碳循环的影响提供科学依据。