Effect of optimized nitrogen application on denitrification losses and N2O emissions from soil in winter wheat-summer maize rotation system in North China.

作者：Xiu‐Bin Wang, Guoqing Liang, Zhou Wei, Sun JingWen, Pei Xuexia, Xia WenJian · 发表于：Plant Nutrition and Fertilizing Science · 年份：2009 · 被引用次数：7 · 研究领域：Environmental and Agricultural Sciences

A field experiment was conducted characterize denitrification and N_2O emission from soil under optimized ni- trogen fertilization in winter wheat/summer corn rotation system in North China using acetylene inhibition-intact soil core incubation technique.Results showed that there were significant seasonal variations of denitrification rate and N_2O emis- sion flux during winter wheat/summer corn growth periods,and positive correlations existed between inorganic nitrogen concentration(NH_4~+-N,NO_3~--N)and denitrification rate.Total denitrification losses and N_2O emission amounts from soil in winter wheat/summer corn rotation system were observed to be reduced with decreasing of N application rate,and which in winter wheat season were found to be less than those in summer corn season.Total denitrifieation losses and N_2O emission amounts under conventional N fertilization were respectively 1.62 and 1.67 times as high as those under opti- mized N fertilization during winter wheat growth periods,and 2.01 and 2.00 times during summer corn growth periods, which N application rate decreased by 30% and postponing N application as compared with conventional N fertilization with an application rate of N 300 kg/ha.Therefore,postponing N application could reduce denitrification losses and N_2O emission through modifying soil inorganic nitrogen concentration.