应用根系层水质模型分析冬小麦-夏玉米轮作体系的农田水氮利用效率 Ⅰ:模型参数的灵敏度分析与标定

Applying Application of Root Zone Water Quality Model to simulate water and nitrogen use efficiency of winter wheat-summer maize double cropping system Ⅰ. Model Calibration and sensitivity analysis

本文利用禹城试验站田间试验数据对根系层水质模型的输入参数进行了灵敏度分析和标定。参数标定后的模拟结果与实测结果的对比显示:土壤体积含水量模拟值的均方根差和平均相对误差分别为0.069cm3·cm-3和-8.57%;土壤硝态氮含量模拟值的均方根差和平均相对误差分别为41.41mg/kg和-69.56%;在冬小麦-夏玉米轮作体系下,作物吸氮量模拟值的均方根差和平均相对误差分别为97.8kg/hm2和50.6%;作物地上部生物量和产量模拟值的均方根差分别为2392kg/hm2和2239kg/hm2,平均相对误差分别为32.8%和22.2%;叶面积指数模拟值的均方根差和平均相对误差分别为2.83和243.8%。模拟结果表明:RZWQM能够较好地模拟冬小麦-夏玉米轮作体系中土壤水动态和作物地上部生物量及产量,可用于模拟分析农田水氮利用效率。但该模型在禹城试验站对土壤硝态氮含量和叶面积指数模拟精度欠佳的原因有待进一步分析。

To find the way of improving water and nitrogen use efficiency in North China plain is of realistic significance for saving water and nitrogen. In this paper, the sensitivity analysis and calibration for the RZWQM （Root Zone Water Quality Model） parameters were carried out using field experiment data at the Yucheng Experimental Station. The results show that the Root Mean square error （RMSE） and mean relative error （MRE） of simulated soil water content are 0.069 cm3·cm-3 and -8.57% respectively. The MRE and RMSE of simulated soil NO3-N content are -69.56% and 41.41mg/kg, respectively. The MRE and RMSE of simulated crop nitrogen uptake for the winter-wheat and summer maize doubling crop system are 50.6% and 97.8kg/hm2, respectively. The MRE of simulated above ground biomass and yields are 32.8% and 22.2% respectively, and RMSE are 2 392kg/hm2 and 2 239kg/hm2, respectively. However, RZWQM failed to simulate Leaf Area Index （LAI） with MRE and RMSE as high as 243.8% and 2.83, respectively. Such results indicate that RZWQM could be used to simulate the dynamics of soil water, above ground biomass and yield. But some improvements for RZWQM should be done for better simulating LAI and soil NO3-N content.