Study On Water Allocation Method And Scheme In Shaanxi Reach Of Weihe River Basin

With the continuous development of population and social economy,the demand of human society for water resources keeps increasing,but the total amount of water resources shows a trend of decreasing year by year,and the contradiction between supply and demand has a further increasing trend.The problems of water resources in China mainly show that there is more water in the south and less water in the north,the shortage of per capita resources,and the mismatch between water resources distribution and economic pattern.As a typical inland province in the north of China,the water resources in Shaanxi Province are abundant in the southern part of Shaanxi Province,while the central and northern part of Shaanxi Province is short.Guanzhong is the core area of economic development,especially the area of water shortage The research on water allocation in Shaanxi section of the Weihe River Basin is not only an important means to ensure the sustainable development of regional economy and sustainable utilization of water resources,but also an important prerequisite for regional water resource dispatching and allocation,as well as an important link in the initial allocation of water rights.Therefore,this study takes Shaanxi section of Weihe River Basin as the research object,and from the basic principle of water allocation,puts forward multiple types of water allocation methods,in order to provide a solid theoretical support for regional water allocation.Considering the complexity of water allocation,a simulation system of water allocation is constructed based on various allocation models and methods proposed in this study,which provides support for comprehensive decision making.The research results of this study are as follows:(1)In order to give consideration to the fairness,efficiency and sustainability of the distribution principle,a distribution method based on subjective and objective weighting is constructed.In this study,a water allocation method based on AHP and entropy weight method was constructed from the perspective of subjective and objective weighting.This method mainly through the construction of multi-type indicators to achieve the overall consideration of the three allocation principles.The results show that the analytic hierarchy process(AHP)has a large randomness in index weighting and is only suitable for decision making.Entropy weight method is relatively objective to index weighting and has a good performance,but the rationality of this method is greatly affected by samples.(2)In order to take into account the current situation of regional water use,an allocation method based on the current pattern of water use was established.In this study,the data of water use during dispatching period in the study area in recent 10 years were collected,and the analysis showed that the water use proportion of each object varied between years,but the annual variation was no more than 5%,and there was no obvious trend.Therefore,this study calculated the allocation of water for each object based on the average historical water use ratio.The results show that the allocation scheme based on this method has a good and objective data basis,which can reflect the water use situation under the current conditions of the region,and can be used as the main basis for the final decision of the allocation scheme.(3)From the perspective of pursuing the maximization of comprehensive utilization benefit of water resources,this study establishes a two-objective optimization model of maximizing comprehensive utilization benefit and minimizing water cost.Based on the NSGA-Ⅱ algorithm with good performance,the model is solved,and three allocation schemes of maximum comprehensive benefit,minimum cost and trade-off of benefit and cost are determined.Through the comparison of several schemes,it is shown that the allocation scheme based on cost-benefit optimization is better.(4)In order to realize the integrated application of multi-type allocation methods,this study built a multi-method integrated simulation system for water allocation in Shaanxi section of Weihe River Basin.The simulation system integrates four water allocation methods,which can visually display the allocation schemes and support the comparative analysis among the schemes,so as to facilitate the decision makers to participate in the decision-making process of water allocation.The integrated application of multiple methods also improves the universal applicability of the simulation system.