石灰氮对设施菜地土壤N_2O排放的影响

Effect of lime-nitrogen on N_2O emission from greenhouse soil

为了研究石灰氮对设施菜地土壤N_2O排放的影响,观测了施用尿素、石灰氮、半量尿素与半量石灰氮混施和对照等4个处理设施菜地土壤N_2O排放以及土壤中氮素变化.结果表明,施用石灰氮能显著降低设施菜地土壤N_2O排放量,对照、施用尿素、施用石灰氮和半量尿素与半量石灰氮混施的N_2O累积排放量分别为4135.80μg·kg^(-1)、5794.25μg·kg^(-1)、1957.03μg·kg^(-1)和4341.31μg·kg^(-1),施用尿素的N_2O累积排放量比对照增加了40.1%,施用石灰氮、半量尿素与半量石灰氮混施比施用尿素分别减少了66.2%和25.1%的N_2O排放量,半量尿素与半量石灰氮混施的N_2O累积排放量与对照的差异不显著(P>0.05).尿素处理的N_2O排放系数为0.17%,而石灰氮处理和半量尿素与半量石灰氮混施处理的N_2O排放系数则分别减少至0.06%和0.13%.由此表明,施用石灰氮是减少设施菜地土壤N_2O排放的一项有效措施.

In order to evaluate the influence of lime nitrogen on N2O emissions from greenhouse soil,laboratory incubation was conducted to investigate N2O emission and soil nitrogen transformation under four treatment（urea,lime nitrogen,urea ＋ lime nitrogen and CK） from greenhouse soils. The results showed that lime nitrogen significantly reduced N2O emission from greenhouse soil. Total N2O emissions with the treatment of CK,urea,CaCN2 and urea ＋ CaCN2 were 4135. 80 μg·kg^-1,5794.25 μg·kg^-1,1957.03 μg·kg^-1,and 4341.31 μg·kg^-1,respectively. The N2O emitted from the urea treatment increased 40. 1% compared with CK treatment. N2O emission from the treatment of CaCN2 and urea ＋ CaCN2 was reduced by 66.2%,25.1% compared with urea treatment. There was no significant difference in the total N2O by emission between treatment of urea ＋ CaCN2 and CK（P〉0.05）. The N2O emission coefficient of N-urea was 0. 17%. However,the N2O emission coefficient was reduced to 0. 06% by N-CaCN2 and 0. 13% by N-urea ＋ CaCN2. The results demonstrated the potential of using lime nitrogen to mitigate N2O emission in greenhouse soil.