Research On Coordinated Optimization And Regulation Of Agricultural Water Use In Huantai Well Irrigation Area,Shandong Province

With the rapid development of the world,more and more industries and sectors need more water,resulting in a sharp reduction in water resources.The shortage of water resources will lead to the potential crisis of environmental resources,food and financial markets,and affect the development of countries and regions.In China,agricultural water consumption accounts for a large proportion,so the shortage of water resources will affect the development of agriculture and food security.Shandong province is a major grain province,the agricultural water consumption in the province’s total water consumption is relatively large,will directly affect the economic benefits of agricultural products.It is of great significance to increase grain yield and improve the utilization rate of water resources by studying the process of water use for crops and the process of rational water distribution and distribution in the field.Taking huantai and typical area in the county of shandong province as the research object,on the field,crop evaporation under different irrigation scheme output analysis,through to SWAP model of typical crops in irrigation area of winter wheat and summer corn crop growth process optimization of water distribution,on this basis,combining with the nonlinear programming and dynamic programming principle,water optimization model is established,combined with the local surface water underground water are available,and the amount of water available partition of different typical years,the area of different cells in the field water process of the water resources and water allocation process It provides a reference scheme and technical support for the efficient utilization of agricultural water in well irrigation area of Huantai county.The main contents and results are as follows:(1)Based on the analysis of the field test data in 2017-2019,it can be concluded that the optimal irrigation amount in the growth period of Winter Wheat in Huantai is 500 mm,while that in summer maize is 450 mm.Too much water can not increase the yield,but inhibit the growth of crops;irrigation in the seedling stage,jointing stage and filling stage is beneficial to increase the yield;the key stage of yield formation of summer maize is in the period of tasseling,jointing and tasseling The reasonable distribution of irrigation amount in the filling stage is beneficial to the growth of summer maize.(2)The field experiment was simulated by the farmland water transport model SWAP,the model was calibrated by using the field data in 2017,and the data in 2018 and 2019 were tested.The simulation results are good,which can reflect the changes of winter wheat and summer maize yield under different irrigation conditions and rainfall patterns.The optimal total irrigation amount and growth of winter wheat and summer maize in different levels of years are obtained Combined with the model,the water production function of the two crops is fitted,which is the basis for the establishment of the optimal control model of water use;(3)Taking the maximum benefit of irrigation area as the goal,the optimal control model is established for the water distribution process among different crops and sub units of different irrigation area.The solution is based on the principle of large system decomposition and coordination,and the total agricultural water consumption of Huantai County is optimized in different level years.The typical local well irrigation area is selected as the research object in the net benefit In the biggest case,the model is used to control the water consumption,which is suitable for the distribution of water in crop growth period,different crops and sub irrigation areas.Through optimization,the net benefit of the well irrigation area in the wet year is increased by 67%,the water consumption is reduced by 21% compared with the current year;the net benefit in the normal year is increased by 51%,and the water consumption is reduced by 12%.Some suggestions are put forward for agricultural water saving irrigation in Huantai well irrigation area.