Winter Wheat Agriculture Based On DNDC Model Water Efficiency Study

In order to clarify the temporal and spatial variation trend of winter wheat agricultural water use efficiency in Daxing District,based on the statistical value of winter wheat yield and remote sensing ET value in Daxing District,a winter wheat denitrification-decomposition model(DNDC model)was constructed to verify the DNDC model at the point and region.(1)Point simulation and verification.Based on the measured data of winter wheat growth period in 2015 and 2016,the winter wheat DNDC model under different irrigation regimes was established.The sensitivity ranking of different crop parameters to the biomass and yield of winter wheat growth period was analyzed.The parameters of DNDC model were determined and verified.(2)Regional simulation and verification.The yield and ET of winter wheat in different soil areas were not the same,but the overall trend remained the same,and the yield varied greatly with rainfall.In 2008,the yield reached the maximum.The average output of 2007-2016 is 5227 kg/hm2,and the average yield of simulation is 4845 kg/hm2.The average value of winter wheat ET simulation is 381.74 mm,and the average value of remote sensing is 392.66 mm.The relative error of yield and ET is average.Less than 13%.The 2007-2016 WP simulation value is between 1.10 and 1.62 kg/m~3,with an average of 1.27 kg/m~3,and the statistical value is between 1.15 and 1.62 kg/m~3.The statistical average is 1.34 kg/m~3.