中文摘要：

将采集于江西鹰潭的45个发育于不同成土母质和不同利用方式的土壤样本,在密闭、淹水、充N2的严格厌氧条件下进行了28d的培养试验（30℃）,在培育过程中,定期测定NO3^--N（加入量为200mg·kg^-1）含量和培养瓶上部空间N2O的含量变化.实验结果表明,N2O含量（N）随培养时间t的变化可用方程N=A×（1-exp（-k1t））-B×exp（k2t）拟合（A表示培养过程中N2O总排放量；B为常数；k1和k2分别为N2O排放速率常数和还原速率常数,拟合值和实测值之间回归方程的决定系数R2=0.84±0.11）.不同土壤之间培养期间N2O总排放量（A）的变异可以用培养7d内被反硝化的NO3^--N量和N2O排放率（A值与28d内被反硝化的NO3^- -N总量的百分比）进行解释（R2=0.829,p〈0.01）.被反硝化的NO3^- -N量则主要受土壤有机碳含量或有机氮矿化量控制,N2O排放率则随k2的增大而呈指数下降（p〈0.01）.由此可见,在该实验条件下,还原N2O能力强的土壤,在相同量的NO3^--N被反硝化的情形下,排放的N2O可能较少.但影响k2值的主要因素还有待进一步研究.

英文摘要：

The potential capacities of N2O emission and reduction to N2 during anaerobic incubation of forty-five subtropical soils in Jiangxi province were determined. Samples were collected from different land use and derived from different parent soil materials, then treated with 200 mg NO3^- -N kg^-1 soil at 30℃ for 28 days. The variations in headspace N2O concentration and NO3 -N, NH4 -N content in the soil slurry with incubation time were measured. The results indicated that the N2O concentration（N） with incubation time （t） was the net result of N2O emission and N2O reduction to N2, which could be described with the equation： N=A×（1-exp（-k1t）） -B×exp（k2t）, whereA is the total N2O emission during the incubation, Bis aconstant, k1 and k2 are the N2O emission rate constant and reduction rate constant, respectively. The average of the determinant coefficients of 45 soil samples （R^2） was 0.84 with a standard deviation of 0.11 （p〈0.05 for all samples）. The total N2O emission （A） during the 28-day incubation varied with the soils and its variation could be explained by the amount of NO3^- -N denitrified in the first 7 days of incubation and the N2O emission ratio （ defined as a percentage of A-value to the amount NO3^- -N denitrified during the 28-days incubation） （R^2=0.829, p〈0.01）. Soil organic carbon content and/or organic nitrogen mineralization were the key factors determining the amount of reduced NO3^- -N. The N2O emission ratio decreased with increasing k2 value （p〈0.01 ）. Therefore, soils with higher N2O reduction capacity under anaerobic conditions would emit less N2O when the same amount of NO3^- -N was denitrified. However, the factors and their mechanisms for controlling k2 are not clear and more work is needed.