尿素施用对稻田土壤甲烷产生、氧化及排放的影响

Effects of Urea Application on Methane Production,Oxidation and Emission from A Paddy Soil

通过田间和培养试验研究了不施尿素(N0kg/hm2)和施用尿素(N300kg/hm2)对水稻生长期稻田土壤CH4产生潜力、氧化潜力和排放通量的影响。结果表明,水稻全生育期内,施用尿素降低土壤CH4产生潜力,并推迟其达到最大值的时间;尿素作为基肥和穗肥施用抑制土壤CH4氧化,而作为分蘖肥施用短暂地促进然后抑制土壤CH4氧化;施用尿素降低稻田CH4排放量。施用尿素通过同时影响CH4产生潜力和氧化潜力来影响稻田CH4排放。

Field and incubation experiments were conducted to study the effects of urea application （N 0, 300 kg/hm^2） on CH（ production potential, oxidation potential and emission during rice-growth season. The results showed that during the entire rice-growth season, urea application decreased CH4 production potential, and delayed the peak time of CH4 production potential. CH4 oxidation potential was inhibited by urea applied as basal and panicle fertilizer, but stimulated temporarily and then inhibited again when urea was applied as tillering fertilizer. Urea application decreased CH4 emission from rice paddy soil by affecting both CH4 production potential and oxidation potential.