Methane emission from West Siberian forest-steppe and subtaiga reed fens

摘要

Methane emission from West Siberian forest-steppe and subtaiga reed fens (that is, fens dominated by Phragmites australis) observed in summer 2013, is considered using the static chamber method. The obtained medians of CH4 fluxes varied from -0.08 to 2.7 mg CH4/m(2) per hour. Eenvironmental factors affecting methane emission are analyzed. It was found that CH4 emissions from the reed fens correlate only with the concentration of salt ions in the wetland water and with the plant community structure. The latter probably also depends on water salinity. It was revealed that in fens the ratio between fluxes of CH4 and CO2 does not depend on the water table level that contradicts the general pattern simulated by mathematical models of CH4 emission. It was found that Phragmites australis fens and similar ecosystems should be considered as a separate wetland class from the point of view of methane emission study.