Influence Factors of Volatile Sulfur Gases Produced from the Decomposition of Methionine in Paddy Soil
水稻土中甲硫氨酸分解释放挥发性含硫气体的影响因素

In order to investigate the source of sulfur gases production and emission in paddy soil,the sulfur containing amino acid was added into the incubated Chinese paddy soil,and the emission of sulfur gases was determined.Three sulfur gases were detected from waterlogged soil:hydrogen sulfide(H2S),carbonyl sulfide(COS) and dimethyl sulfide(DMS).When methionine was added,detected concentrations of DMS increased obviously,dimethyl disulfide(DMDS) and methyl mercaptan(CH3SH)were also detected under aerobic condition,COS emission also increased obviously.While the concentration of H2S did not changed obviously.These results showed that the decomposition of methionine may be the one of sources of emission of COS,DMS,DMDS and CH3SH.Under ambient atmosphere,the emissions of DMDS and CH3SH were lower than under anaerobic condition(nitrogen atmosphere),that of DMS was higher than under anaerobic condition.It was showed that the production of DMDS and CH3SH from the decomposition of methionine in paddy soil need strong reduction situation,the microorganisms that produced these gases from methionine need strict anaerobic condition.Under illumination condition,the emission amount of most sulfur speciation was higher than under no illumination.The suitable water/soil ratio of most microorganisms producing sulfur gases was 50%.Microorganisms producting sulfur gases neet a special pH of soil.