Аннотация:Methanogenesis is one of the most important terminal processes in the microbial degradation of organic matter in many anoxic environments. Since ancient times, methane was known as a combustion gas, but its microbiological origin was proved only in the nineteenth century. The contribution of methane to the global warming and its beneficial importance in ecological biotechnology and bioenergetics dictate the need in proper estimations of its fluxes and measurements of its production rates in different microbiological processes.
Measuring methanogenesis is mostly conducted in laboratory experiments with different types of methanogenic samples, in fields or in ruminants. The samples used for such measurements are either liquid methanogenic cultures and slurries prepared by homogenization and dilution or intact soil cores. All types of methanogenic samples are incubated, and accumulated CH4 is analyzed in order to calculate methanogenesis rate. The samples as slurries incubated under laboratory conditions are referred to as potential production rates, whereas rates measured in intact samples or in fields are referred to as actual (in situ) production rates.
To initiate methanogenesis, characteristic substrates of methanogens are used as additions to the samples. Radiotracers are also used to measure rates of certain methanogenesis pathways in samples.
Classification of methods of measuring methanogenesis is based on the mass balance equation relating the rate of change in concentration of methane with its source and flux. The two major methods are described in detail.