论文部分内容阅读
通过连续3年在中国浙江杭州的大型稻田原状土柱渗漏计中开展稻麦轮作稻田中N2O排放规律的研究,探讨了不同作物生长季节、不同年份、不同氮肥用量和氮肥品种对N2O排放的影响。结果表明:稻季的N2O排放主要发生在施肥之后,呈单高峰特征;麦季N2O排放则发生在施肥和较大降水之后,呈多高峰特征,麦季排放与降水有密切相关;不施氮情况下,稻田中N2O排放通量和累计排放量都是稻季高于麦季,稻季分别为麦季的1.97倍和1.34倍;施氮情况下,稻季与麦季排放通量和累计排放量则差别不大,排放通量是稻季略高于麦季(+17%),而累计排放量则是麦季略高于稻季(+21.96%).;施加氮肥可以促进N2O的排放;尿素的排放因子大于硫铵;在麦季施N100~1000 kghm-2的条件下,尿素的排放因子值为0.75~1.31,硫铵为0.15~0.16;在稻季施N150~300 kg hm-2的条件下,硫铵的排放因子值为0.19~0.20;在中国浙江省杭州稻麦轮作稻田中,N2O本底排放量为0.12~0.25 kgN2O-Nhm-2 yr-1,施肥引起的N2O排放占总排放的33%~59%。渗漏水中的N2O/NO3比值随种植季数而增高,可用乘幂关系式表达。
The N2O emission from paddy fields under rice-wheat rotation was studied in a large-scale paddy soil column leakage meter in Hangzhou, Zhejiang Province, China for three consecutive years. The effects of different crop growth seasons, different years, different amounts of nitrogen fertilizer and nitrogen fertilizer on N2O emission influences. The results showed that the N2O emission in rice season was mainly single peak after fertilization, while the N2O emission in wheat season was multi-peaked after fertilization and larger precipitation. There was a close correlation between N2O emission and precipitation in wheat season. , The N2O fluxes and cumulative emissions in paddy fields were higher in rice paddy than in wheat paddy and 1.97 and 1.34 times in paddy in wheat paddy respectively. While the emissions were slightly higher than the wheat season (+ 17%), while the cumulative emissions were slightly higher than the rice season (+ 21.96%); the nitrogenous fertilizer could promote the N2O The emission factor of urea is larger than that of ammonium sulfate. Under the condition of N100 ~ 1000 kghm-2, the emission factor of urea is 0.75-1.31 and ammonium sulfate is 0.15-0.16. -2, the emission factor value of ammonium sulfate was 0.19-0.20. In the rice-wheat rotation paddy field of Hangzhou, Zhejiang Province in China, the N2O emission was 0.12-0.25 kgN2O-Nhm-2 yr-1 and the N2O Emissions accounted for 33% to 59% of the total emissions. The ratio of N2O / NO3 in seepage water increased with planting seasons, which can be expressed by power relation.