Methane production from a tropical vertisol

The current study evaluated how the biomass of crops varying in C: N contribute to CH4 cycling in a tropical vertisol. Soil was amended with the biomass of wheat, maize, soybean and chickpea at 1% w/w. Soils were incubated at 100% moisture holding capacity and 60% of field moisture capacity. The former condition was to facilitate methanogenesis and other for CH4 consumption. After incubation, soils were analyzed for organic carbon, available nitrate, abundances of methanogens and methanotrophs. Study highlighted that crop biomass incorporation into soil stimulated CH4 cycling processes including both CH4 production and CH4 consumption. Carbon content of crop biomass is the important property to regulate CH4 cycling.Higher the carbon contents favored CH4 cycling process as the carbon content of crop regulated soil organic carbon and available nitrate. Available nitrate content was high in CH4 consuming soil than CH4 producing soils.This was attributed to the nitrifying property of the methanotrophs. Result seeks further research to underpin the role of organic carbon on soil CH4 consumption potential.