Research On Optimal Allocation And Evaluation Of Urban Water Resources Based On "Three Red Lines" Constraints

With the rapid growth of urban economy,the contradiction between water resources and socio-economic and ecological development is increasingly prominent,which hinders the sustainable development of the city.In this paper,Liuzhou city is taken as the research area,according to the water supply situation of different water sources and the water demand of different water departments,a multi-objective optimal allocation model of urban water resources based on the constraint of "three red lines" is proposed.Pareto optimal solution method is used to solve the model,and the non-inferior solution set is used as the allocation scheme set.Based on TOPSIS method and grey correlation analysis,a comprehensive evaluation model of water resources optimal allocation scheme is established,and the best water resources optimal allocation scheme is selected,which provides scientific basis for the optimal allocation of water resources in Liuzhou city and supports the overall and coordinated development of social economy.The main contents of this paper are as follows:(1)Aiming at the problems of uneven distribution of water resources in time and space,insufficient runoff regulation ability and increasingly prominent contradiction between supply and demand of water resources in Liuzhou City,the multi-dimensional system evolution characteristics of water resources,economy and ecological environment affected by high-intensity human activities and hydrological changes are identified.The total amount,structure and law of water demand of each water using department in different level years and different water conditions are studied.The differences of water resource demand in different sub districts of Liuzhou city are analyzed systematically to provide decision-making basis for optimal allocation of water resources.(2)Based on the supply and demand of water resources,with the "three red lines" as constraints,and with the coordinated development of society,economy and ecological environment as the goal,the multi-objective water resources optimization allocation model of the city is constructed based on the "three red lines" constraints.(3)Based on the future water conservancy project planning,Pareto optimal solution is adopted to solve the multi-objective problem of water resources optimal allocation,and 100 non inferior solutions obtained are taken as 100 allocation schemes of water resources optimal allocation.(4)The reevaluation of the optimal allocation schemes of water resources is an important part of the rational allocation of water resources.AHP and variation coefficient method are used to determine the weight of indicators.At the same time,the comprehensive evaluation model of water resources optimal allocation scheme is established by combining TOPSIS method and grey correlation analysis.According to different allocation schemes,the optimal allocation scheme of water resources in Liuzhou city is selected to promote the sustainable and healthy development of urban society,economy and ecology.