【摘要】 为了探讨水稻土中含硫气体产生和释放的途径 ,在室内培养条件下 ,测定了南京水稻土中含硫气体的释放 .从该淹水土壤中测出 3种含硫气体 ;羰基硫 (COS)、二甲基硫 (DMS)和少量硫化氢 (H2 S)气体 .当土壤中加入甲硫氨酸后 ,DMS气体的释放量有了明显增加 ,此外还有大量甲硫醇 (CH3SH)和二甲基二硫 (DMDS)气体测出 .而 COS在好氧条件 (普通大气淹水 )下的释放量明显增加 ,在厌氧条件 (充氮淹水 )下的释放量变化不明显 ;只有 H2 S的释放量几乎没变 .这些结果表明 ,甲硫氨酸的分解可能是 COS、DMS、CH3SH和 DMDS的产生源之一 ,且释放含硫气体的种类明显不同于胱氨酸和半胱氨酸 .在好氧 (普通大气 )条件下 ,DMDS和 CH3SH的释放量低于厌氧情况 (充氮气 )下的释放量 ,DMS则高于厌氧条件下的释放量 .这表明 ,水稻土中甲硫氨酸分解产生 DMDS和 CH3SH需较强的还原条件 ,产生这 2种气体的微生物需要严格的厌氧条件 .产生 DMS的微生物则比前者需要高一些的含氧量 .土壤 p H值和含水量及光照对甲硫氨酸分解释放含硫气体均有影响 .各含硫气体在持水率 50 %、普通大气、光照条件下的释放量明显高于无光照条件下的释放量 .更多还原

【Abstract】 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(H 2S),carbonyl sulfide(COS) and dimethyl sulfide(DMS).When methionine was added,detected concentrations of DMS increased obviously,dimethyl disulfide(DMDS) and methyl mercaptan(CH 3SH)were also detected under aerobic condition,COS emission also increased obviously.While the concentration of H 2S 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 CH 3SH.Under ambient atmosphere,the emissions of DMDS and CH 3SH 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 CH 3SH 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.更多还原