Seasonal dynamics of methane emission from wetlands

Abstract

In view of its impact on the earth’s climate, methane despite its low atmospheric concentration, has assumed importance in recent years. Natural wetlands are one of the major sources for methane emission to the atmosphere. This study was carried out to find out the seasonal fluctuation in CH4 fluxes from water bodies and the difference in the methane efflux from vegetated and unvegetated surfaces of natural and man-made water bodies as well as to investigate the edaphic factors controlling the methane production and emission. The results revealed that there were seasonal fluctuations in methane emission from both the natural and man-made water bodies. Evidently, CH4 emission from the vegetated surface was many times higher than that from the unvegetated surface of the same water body, indicating the importance of vegetation in methane transport from sediments to atmosphere. Study of several edaphic factors like pH, redox potential, temperature and organic carbon of 10 water bodies, including 5 man-made ponds showed that all these factors largely determined CH4 production in the sediment as reflected by its emission from water bodies.