亚热带森林中林下植物根系进入凋落物层生长是一种常见而易被忽视的现象，研究根系生长对凋落物分解的影响，有助于深入理解全球气候变化背景下根系生命活动对森林地下生态过程的调控机制。本研究以中亚热带常绿阔叶林为研究对象，在前期野外原位分解实验中发现根系生长对凋落物分解起促进作用，为深入理解其作用机制，拟通过分室系统实验分析进入凋落物层中生长的根系生物量对凋落物分解初期机械碎裂作用的强度；采用15N同位素示踪技术监测凋落物分解过程中根系的N素吸收作用对凋落物质量改变和分解速率的影响；并基于根系分泌物的原位收集，进一步通过人工添加不同C:N化学计量特征根系分泌物于凋落物分解环境中，研究根系分泌物对凋落物分解过程中微生物群落动态的影响。基于此综合阐明根系生长对亚热带常绿阔叶林凋落叶分解的影响及对分解进程的调控作用，充分认识根系分泌物对凋落物分解的激发效应以及根系生长对凋落物分解影响的微生物学机制。

It’s a common and easily neglected phenomenon for understory plant root growth into the litter layer in subtropical forests, so studying the influence of root growth on litter decomposition contributes to deep understanding of the mechanism of combined effect of root system activity on underground ecological process in the context of global climate change. Mid-subtropical evergreen broad-leaved forest taken as study object, it’s found that root growth facilitated litter decomposition through early-stage field in-situ experiment in this study. For further understanding of its action mechanism, it’s planned to analyze the action intensity of mechanical fragmentation of the living root and their biomass to leaf litter in the early stage of decomposition through the experiment of dividual chamber microcosm system; 15N isotope tracer technique was used to monitor the influence of absorptive effect of root system on N elements on quality change and decomposition rate of litter during litter decomposition process; based on in-situ collection of root exudates and by artificially adding root exudates of different C:N stoichiometric ratios into litter decomposition environment, the influence of root exudates on the quantity and composition of the microbial community on leaf litter surface during litter decomposition process was studied. Then a comprehensive exposition of influence of root growth on leaf litter decomposition in subtropical evergreen broad-leaved forest and its regulatory effect on decomposition progress was given for the sake of further understanding of priming effect of root exudates on litter decomposition and microbiological mechanism of the influence of root growth on litter degradation.