从微观尺度上阐明湿地土壤碳库分子结构特征对水热条件波动的响应机制是预估未来气候变化情境下湿地土壤碳库稳定性的基础与核心问题。本项目选择东北区典型沼泽、沼泽化草甸及泥炭地，结合面上调查、室内模拟及野外原位OTC增温控水实验，利用Py-GC/MS(热裂解-气质联机)及同位素（δ13C、δ15N）等分析测试技术，分析东北典型湿地土壤碳库分子结构特征，通过生物标志物及同位素特征识别土壤稳定性碳分子结构及来源；以“空间代替时间”的方法，结合原位OTC增温控水实验结果，分析不同水热组合、植被组成、NPP输入及枯落物分解过程对土壤稳定性碳库分子结构特征及来源变化的主效应及其交互效应，识别并阐明主要影响因子及其作用机制；利用Biomod2及LPJ模型模拟未来气候变化背景下东北区湿地分布、植被演变及NPP变化，预估未来气候变化情境下东北地区湿地碳库稳定性及时空分布格局，并提出适应未来情景变化的适应性对策。

Deciphering how molecular characteristics of soil carbon pool response to hydrothermal condition variations on micro scales is promise for elucidation of assessing stabilities of wetland soil carbon pool facing future climate change scenarios. In the present project, representative wetland types, including marsh, marshy meadow and peatland, were chosen as study areas for general filed investigation and in-situ Open Top Chambers (OTC) experiments realizing warming and precipitation adjustment. laboratory microcosm experiments are also involved, aiming to depict molecular features of wetland soil carbon pools in Northeast by Pyrolysis - gas chromatography-mass spectrometry (Py-GC/MS) technology. Biomarker and stable isotopes (δ13C、δ15N) were employed to identify stable carbon molecular and to fingerprint their sources. By means of the method of space instead of time and results from OTC experiments, we hope to differentiate the main and combined effects of hydrothermal conditions, plant cover, net primary productivity (NPP) input and litter decompositions on variations of molecular structure shifting and origins of stable carbon in wetland soil. Two ecological models, Biomod2 and LPJ, are applied to predict potential changes of wetland distribution, vegetation succession and NPP under future climate change scenarios. We finally hope to forecast and assess stability changes and spatial distribution of wetland soil carbon pools, and to provide the flexible countermeasure to avoid the adverse effects of future climate change on wetland soil carbon pool. Our results would better the current understanding of feedbacks between climate change and carbon circulation on regional scale.