Optimization Of Irrigation Schedule Of Winter Wheat-Summer Maize Multiple Continuous Cropping

Huanghuai Plain is an important grain production base in China,the reason why the grain yield is not high is due to the limitation of irrigation water resources,that is to say,it is due to the contradiction between supply and demand of water resources.In the context of the increasing demand for irrigation water resources and the increasing demand for food,it is very important to produce more grain under the condition of limited water resources.The purpose of water-saving irrigation experiment in Yuanyang County,Henan Province is to study and determine the relationship between winter wheat,summer corn and water consumption by setting different soil water content levels,so as to determine the reasonable and scientific irrigation system of crops,avoid the waste of irrigation water resources and make crops achieve high yield at the same time.Methods: In this experiment,winter wheat and summer corn set different water content lower limit level,each level 3 repeat study.Research contents: First,the water consumption and reference crop demand are calculated by using water balance method and Penman formula,and then the crop coefficient is calculated at different growth stages of crops.Based on the knowledge of water consumption and yield,a model is established to find out the water sensitivity index of different growth stages and obtain the suitable crop-water model as the Jesen model by checking.The following conclusions can be drawn from this experiment:(1)According to the meteorological data observed by Yuanyang weather station and the data obtained from the experiment,the reference crop evapotranspiration and crop water consumption in each stage of winter wheat and summer maize were calculated by using Pengman formula(Penman-Monteith)and water balance equation,and the crop coefficients of different growth stages were estimated on this basis.Thus,it can be obtained that the water demand law of winter wheat and summer corn is roughly parabolic,and the peak value of winter wheat reaches 5.6 in jointing-pumping period mm/d,and the peak value of summer corn is6.75 in pumping-grouting period mm/d,and then the water demand intensity decreases gradually.(2)Jesen?Blank?Minhas?Stewart four models were established according to the water consumption and corresponding yield in different stages of theexperiment.The water sensitivity indexes of the four models were obtained by using the least square method.The whole performance of the four models was as follows:the water sensitivity period of winter wheat was joint-drawing stage and heading-grout stage,and the water sensitivity period of summer corn was during male extraction stage.Finally,the irrigation sensitivity stage of winter wheat and summer corn was Jesen model.Finally,this article discusses the water-saving technology and management model of Xinxiang City through three different aspects according to the current water-saving form.(3)The important use of the water production function is to determine the optimal irrigation system for crops.Through determining the Jesen model as the objective function and using the MATLAB programming method to optimize the irrigation system of winter wheat and summer corn,finally,after optimizing the crop irrigation system,we can get that the relative yield of winter wheat and summer corn is higher when the irrigation amount reaches about 350 mm,and the increase of yield will be relatively small when the irrigation amount is greater than 350 mm,thus the optimized irrigation system when high yield and water saving can be obtained.