Study On The Optimal Allocation Of Multi-water Source Complex System In Irrigation District

Water resources is the basic resources for human activities and the development of social economy is more and more rapid. Endless stream of water resources problems have emerged one after another, resulting in the relationship between supply and demand of water resources ha d a serious imbalance. How to balance this relationship between supply and demand, improved the effective utilization of water resources, to ensure the proper and reasonable utilization of water resources became a hotspot topic nowadays in the field of water resources. Previous research mainly focuses on the urban. These results were used in view of the different water sources among different sectors distribution in the urban. But there was little research on the allocation of water resources in irrigation area. The agricultural sector could be seen as the largest sector of water use and the irrigation area was the main individual of water resources utilization of the agricultural sector. The optimized allocation of irrigation water resources was an important way to solve the shortage of water resources and relieve the pressure of water.In this paper, the multiple uncertainties and dynamic complexity of multi water source system of typical irrigation districts in Heilongjiang Province were considered. There were several uncertainty optimization technique coupled together which solved the problem of water resources allocation in the period of crop growth under the condition of uncertainty.The specific research contents are as follows.(1) The advantages of multi-stage stochastic programming and interval programming were comprehensive analyzed and build the model. In this paper, the weight coefficient of crop water sensitivity index was introduced in the model, it was improved the traditional interval multi-stage stochastic programming model. The improved model was applied to the Heping Irrigation area in Heilongjiang province. It could be used to solve the allocation of water resources during the period of crop growth.(2) Interval multi-stage stochastic programming model had limitations in the application. On the basis of this model, combined with the method of robust optimization, the risk decision was introduced in the model, and constructing interval multi-stage stochastic robust optimization model. And the model was applied to the management of water resources in the irrigation area. The results of the model were compared and analyzed.Results showed: the first Multi-stage stochastic programming model could be used to deal with the multiple uncertainties of the multi-source system and the dynamic complexity of the system in the process of water distribution. In different water flow situation, according to the weight coefficient of water sensitive index in each growth stage, the managers could determine the water sensitivity. By tradeoff the reducing of irrigation water and increasing of water diversion, the water resource could be distributed in the crop growing period efficiently, so that it was realized the dynamic process of optimal allocation of irrigation water in different growth stages of irrigation districts. the second The risk decision problem was introduced interval multi-stage stochastic robust optimization model. With the increase of the robust coefficient, the feasibility of the model was enhanced. This model could not only solve the uncertainty and dynamic complexity of irrigation system, but also balance the stability of the system, and enhance the stability of the system and the feasibility of solving the model.In a word, the traditional interval multi-stage stochastic programming model was coupled with the water production function and the model was improve. Thus, the improved model was more suitable for the optimal allocation of water resources in different stages of crop growth. And robust optimization theory was coupled with the improved interval multi-stage stochastic programming model that made up for the risk of defects of the model. This action enhanced the stability of the system and the feasibility of the model solution. A more stable allocation of water resources was generated. It was conducive to sufficient and effective balance the relationship between system risk, stability of the system and the net benefit of irrigation area and the three party in the decision of the management of water resources allocation in multi-water source composite system of irrigation districts. The operating results of the models provided a theoretical basis for improving the irrigation water use efficiency and ensur ed the sustainable utilization of water resources.