Study On Corn Optimize Irrigation Schedules Of Sprinkler Irrigation In Eastern Area Of Inner Mongolia

Under the background of critical shortage of water in Tong Liao,the another conducted the experiment of deficient irrigation of corn in the field,making the quatitative research about how different amount of irrigation (three levels) and fertility of soil (there levels) impact the growth,water consumption,yield and water productivity of corn under the large sprinkler irrigation condition.after calculating the actual measurement of data,the author gets crop coefficient and choose the suitable crop water model of the area.Based on the model of Jensen,the author concludes the optimal irrigation schedule by using dynamio programming.The main idea of the thesis si as follow:(1)By analyzing the change of plant height,stem diameter and leaf area,the author finds that the growth of the plant height of corn is S curve,and the growth of stom diameter and leaf area is parabolic.The growth index of corn change rapidly in jointing stage. When the level of irrigation amount and fertilizing amount is high and medium,the plant height,stem diameter and leaf area will be improved with the increase of irrigation amount and fertilizer,while in the low level,there is no signification correlation between the change of amount of irrigation and fertilizer and the growth of corn.Compared on the whole,the author finds that the change of amount of irrigation has more impaction on the height irrigation of corn and the stem diameter than the change of fertilizer.(2)Under the condition of sprinkler irrigation,water consumption of corn in the whole growing stage increases first and the decreases and increase at last.Water consumption of corn in every growing stage is that jointing stage> filling stage> tasseling stage> seeding stage> emergence of seeding.The change of intensity of daily water consumption and modulus of water consumption is that decreaste at last stage.They are biggest in the jointing stage.The author concludes that jointing stage is the sensitive stage of water,and water is necessary in this stage.(3)After analyzing of production rate of water,the author concludes that SF-4 lead to the highest production rate of water,while the water consumption is not the biggest one.lt can reach the biggest one under the condition of high water and high fertilizer.The utilization efficiency of water is 1.91 kg/m3,so it is not because the more water consumption lead to the high yield of water.The relationship between water consumption and production is quadratic curve.More irrigation amount leads to more production.When reaches a certain value. Production will be reduced.(4)The value of ETo changes between 0.97 to 8.81 mm/d,and it is increase first and then decrease.At last the author concludes the crop coefficient under the condition of irrigation in eastern region of Inner Mongolia.Ks(early growth stage)=0.39,Ks(roped growth stage)=0.99,Ks(middle growth stage)=1.09,Ks(late growth stage)=0.46,the change crop coefficient is that increase first and then decrease on the whole.(5)The author describes water allocation and production prediction in every stage in the local by using the Model of Jensen.The sequence of level of water sensitivity is that jointing stage,grain filling stage,tasseling stage,emergence of seeding and seeding stage.The sensitive periods of water shortage are jointing stage and grain filling stage. The author use of dynamic programming method.Then formulates the optimum irrigation schecluce.Corn irrigation water is best achieved in the 225 mm.