典型潮土N_2O排放的DNDC模型田间验证研究

摘要

The validities of DeNitrification-DeComposition（DNDC） model and the simulation parameters were examined by using field experiment data obtained from typical fluvo-aquic soils at Hengshui experiment station,Hebei Province.The results show that the DNDC model could be well used for simulating the temporal variations of soil moisture and mean daily temperature at soil surface during winter wheat/summer corn growing seasons.There is significantly positive correlation between soil N2O flux and soil moisture（water filled pore space）,while the correlation between soil N2O flux and soil temperature is not significant during winter wheat/summer corn growing seasons.The peaks of N2O emission are mainly affected by rainfall and nitrogen application,and the simulated values are relatively close to the measured ones for peaks of N2O emission and its appearance time.It is necessary to modify some parameters of the DNDC model for capturing seasonal N2O emission fluxes precisely.According to sensitivity test on the DNDC model,soil N2O emission is found to be sensitive to the changes of the amount and time of nitrogen application,soil initial inorganic nitrogen content and soil texture,among which the amount and time of nitrogen application are the most sensitive factors.By modifying some parameters based on the local soil properties and management,the DNDC model could become a powerful tool for estimating N2O emission from agro-ecosystem.%利用典型潮土N2O排放的田间试验数据对脱氮-分解模型（DNDC）及其参数进行验证。结果表明,DNDC模型能较好地模拟田间实测到的冬小麦、夏玉米季土壤湿度和土壤日平均地表温度的动态变化。小麦和玉米季土壤N2O排放通量与土壤水分（WFPS）呈显著正相关,与土壤温度相关性不大。田间实测到的N2O排放高峰主要受降水和施肥的影响,在N2O排放峰的峰值和出现时间上模拟值与实测值较接近,但准确地捕捉N2O季节性的排放通量仍需对模型进行修正。通过比较施肥、土壤和田间管理等输入参数的改变对DNDC模型进行灵敏性分析,氮肥用