不同施肥类型对北方稻田土壤温室气体排放的影响

利用静态暗箱-气相色谱法研究了吉林省延边地区不同施肥类型对水稻土壤CO2、CH4和N2O排放通量的影响。结果表明,稻田3种温室气体的排放存在明显的季节特征,CO2排放主要集中于8~10月,而CH4排放以7、8月为主,水稻生育盛期时N2O表现出明显的负排放特征,净排放发生于移栽期及秋季晒田期;有机肥与化肥配施促进了水稻生育盛期CO2和CH4的排放,导致生长季CO2和CH4排放总量显著高于单施化肥和单施有机肥处理,而单施化肥处理促进了生长季N2O净排放。水稻植株促进了水稻生育期6~8月稻田CO2和CH4的排放,与无植株相比,月均通量分别增加了42.9%~226.1%和146.6%~418.9%。生长季土壤温度对稻田CH4排放具有显著影响,但对CO2和N2O排放影响不显著。

Effect of Different Fertilizer Types on Emissions of Greenhouse Gas in the Northern Paddy

The influence of different fertilizers on emissions of CO2、CH4 and N2O from paddy soil in Yanbian area was stud-ied by using the static opaque chamber-GC techniques. The results showed that the emissions of CO2, CH4 and N2O present-ed obvious seasonal characteristics, CO2 emissions mainly concentrated in August to October, but CH4 emissions mainly con-centrated on July and August, N2O showed obvious negative emission characteristics at rice vigorous growing stage, and net emissions of N2O occurred at transplanting stage and at autumn field-dried stage. Combined application of organic manure with chemical fertilizer promoted CO2 and CH4 emissions at the rice vigorous growing stage, and led to higher total emissions of CO2 and CH4 in total growing season than single application of chemical fertilizer or organic fertilizer. The chemical fertil-ization promoted net N2O emissions in growing season. Compared with no plants, the rice plants promoted CO2 and CH4 e-missions of paddy ecosystem during the growth period (June to August), and increased mean emissions per month 42.9%~226.1% for CO2 and 146.6%~418.9% for CH4 respectively. The soil temperature in the growing season significantly affected the emissions of CH4, but had no significant effect on the emissions of CO2 and N2O.