Study of the Production Processes of Marine Biogenic Methane and Carbonyl Sulfide Using Stable Isotope Analysis

rine organisms, the gas phase oxidation of biogenic CS2 and dimethylsufide (DMS) (Watts 2000). However, it has been suggested that the ocean can also be a sink of COS in a certain period of the year, because it can be hydrolyzed (Kettle et al. 2002). The material budget of COS between the ocean and the atmosphere has a large uncertainty due to the lack of observations. Stable isotope ratios have been used to elucidate the material cycle of environmental substances since they reflect the origin of the substance, and the physical and chemical processes. The purpose of this study is (1) to reveal the production and consumption processes of CH4 by analyzing hydrogen and carbon isotope ratios in natural seawater, and water samples in laboratory simulation experiments, and (2) to develop a method for high-sensitive and high-precision sulfur isotope analysis of COS to know its signature in the atmosphere and ocean. Study of the Production Processes of Marine Biogenic Methane and Carbonyl Sulfide Using Stable Isotope Analysis