Abstract:Three methods have been mainly used to quantify methane oxidation in paddy fields, namely, soil anaerobic incubation, the use of methane oxidation inhibitors and stable carbon isotopes. Methane oxidation ratios measured by soil anaerobic incubation were overestimated, and most of the values obtained by this method were above 50%, higher than the values obtained by other methods. In the inhibition studies, methanogenesis was reduced or stimulated while methane oxidation was blocked, depending on the inhibitor's concentration. Stable carbon isotopes used to quantify methane oxidation was nondestructive and more sensitive than other methods, but further studies on δinitial、δfinal and α were still necessary.