水热波动及氮输入对北方沼泽湿地碳固定过程影响及其作用机制是目前气候变化研究的热点问题。本项目拟在搜集资料并基于137Cs定年对东北沼泽湿地碳固定速率评估的基础上，选择典型小叶章湿地、毛果苔草湿地及泥炭藓湿地进行原位OTC开顶箱增温控制实验，通过设置不同的增温幅度、水位及氮输入负荷，结合枯落物分解实验，监测湿地生态系统植被（叶、茎、根、枯落物）生物量及其品质、枯落物分解、微生物群落（微生物量碳、氮、磷）的变化及环境参数，分析其与碳固定速率变化之间的关系，评估水热波动及氮输入对湿地生态系统碳固定速率的促进或减缓作用，分析不同情境下影响碳固定速率变化的关键因素、过程及作用机理，基于BioMod2模型预测不同气候变化情景下未来东北湿地潜在分布区变化，评估未来东北湿地固碳潜力及汇碳功能变化。研究结果对深入认识气候变化及氮输入多因子协同作用下湿地水-热-碳-氮耦合循环过程并制定湿地适应性对策意义。

Impacts and driving mechanisms of warming and water level flucation compling with nitrogen input on carbon sequestration potental by northern wetlands in China are hot spot of climate chang research. Based on literature meta-analysis and information collection, this projects aimes to evaluate carbon sequestration potential of typical wetlands in Northeast China by 137Cs dating technology. A sets of opening-up box (OTC) are built to relize warming, water fluctation and nitrogen iput control, and to operate litter decompostion experiment, to monitor biomass and quality of wetland vegetations (leaves, stems, roots and litters) and enviromental factors, and to analyze microbie commuinites and activities (microbiomass carbon, nitrogen and phosphorus). Results from on simulation and field experiments were to reveal relationships between carbon accreting rate and environmental factors, to assess the acceleration or slowing effects of warming, waterlevel flucation and nitoren input and their interaction on wetland carbon sequestration rates, to find the key factor, porcess and driving mechanisms of environmental factors on carbon sequestration potential under different scenarios. Based on BioMod2 models, the potental wetland distribution areas in Northeast China are predicted in order to estimate carbon sequestration potential change. Results of this projects are import to a deeper appreciation of water-heat-carbon-nitorent interactly circulation processes doubly affected by climate change and nitrogen input, and are with guidence signficance to adapative police establishiment for wetlands.