农田生态系统N_2O排放的数值模拟研究

Simulation of N_2O Emissions in Agroecosystems

综合大气化学等多学科最新研究进展 ,建立了农田N2 O排放数值模式 ,模式较好地模拟了农田生态系统中N2 O排放过程 .利用模式分析了气象因子对N2 O排放影响 .结果表明 :苏州稻田N2 O排放量与生长期平均气温存在显著正相关 ,与总辐射和降水量相关不明显 ;功率谱分析表明N2 O排放量存在 7～ 9年的变化周期 ,与平均温度变化周期比较接近 .模拟气候变化对N2 O排放的可能影响表明 :气温比目前升高 1℃ ,苏州稻田N2 O排放量将平均增加 4 5 % .

A numerical model for simulating N 2O emissions in agroecosystem was established. Validation of the model with the observed data showed that the model simulated the process of N 2O emissions in fields fairly well. The numerical analysis showed that the N 2O emissions were interrelated well with average temperature during rice growth periods. Analysis of N 2O emissions and meteorological factors by using power spectrum found that the change of N 2O emissions had 7～9 year cycles. Sensitivity test showed that the N 2O emission increased with temperature enhancement.