与铁还原偶联的甲烷厌氧氧化作用(简称Fe-AOM)的发现是当前甲烷循环研究的最新突破，但目前尚缺少证据支撑它在海洋沉积环境中普遍存在的理论假设，更无研究详细阐释其运行机制。莺歌海岭头岬近岸冷泉渗漏区具有丰富的陆源高价铁输入和较高的甲烷释放通量，是Fe-AOM研究的理想场所。本项目拟以该区沉积物柱为对象，展开如下工作：1.利用地球化学手段来追踪Fe-AOM在原位孔隙水中的地球化学信息记录；2.利用地微生物学方法，研究原位沉积环境中的微生物群落结构纵向演替规律，并聚焦甲烷厌氧氧化与铁、硫还原代谢微生物的空间共生关系，为Fe-AOM提供分子证据；3.以原位沉积物开展模拟实验，人工添加铁氧化物和同位素标记甲烷，刺激Fe-AOM活跃，推算Fe-AOM的发生机理。开展此课题将为海洋环境中普遍存在Fe-AOM的假说提供新证据，对进一步理解海洋沉积物中甲烷的生物地球化学循环具有重要的科学意义。

Anaerobic methane oxidation coupled with iron reduction (Fe-AOM) is the new breakthrough in the studies of methane cycle, but the evidence for its universal exsit in the marine sedimentary environment and explaination for its occcurance mechanism are still lacking.The cold seeps, that have abundant terrigenous iron input and high methane flux, on the seafloor nearshore Lingtou promontory, Yinggehai, is an ideal place for this research. Therefore, this proposal intends to consider the sediment columns in the cold seeps area as the study object, and carry out the following three research aspects:1.Using the geochemical methods to reveal the change regularity in response to Fe-AOM occurred in situ sedimentary environments; 2. Using microbiological methods to study the vertical changes of microbial community structure, and focusing on the spatial relationship between AOM and iron, sulfur reducing microbial metabolism, and to track the microbiological evidences for the presence of Fe-AOM in this sediment column; 3. Constructing in situ micro-cosmic environment, to calculate the rate of iron reduction and AOM, and evaluate its internal occurrence mechanism. This research can not only provide the important basis for the hypothesis that the existence of Fe-AOM in marine environment, but also has important significance for further understanding the methen geochemical cycle in the marine sedimentary environments.