METHANE PRODUCTION AND METHANE CONSUMPTION - A REVIEW OF PROCESSES UNDERLYING WETLAND METHANE FLUXES

Potential rates of both methane production and methane consumption var y over three orders of magnitude and their distribution is skew. These rates are weakly correlated with ecosystem type, incubation temperatu re, in situ aeration, latitude, depth and distance to oxic/anoxic inte rface. Anaerobic carbon mineralisation is a major control of methane p roduction. The large range in anaerobic CH4:CO2 production rates indic ate that a large part of the anaerobically mineralised carbon is used for reduction of electron accepters, and, hence, is not available for methanogenesis. Consequently, cycling of electron accepters needs to b e studied to understand methane production. Methane and oxygen half sa turation constants for methane oxidation vary about one order of magni tude. Potential methane oxidation seems to be correlated with methanot rophic biomass. Therefore, variation in potential methane oxidation co uld be related to site characteristics with a model of methanotrophic biomass.