Analysis Of Water Resources Supply And Demand In The Wuding River Basin And Ecological Scheduling Study

The WuDing River Basin is located in the drought semi-arid areas in the northwest.With the development of socio-economic development and human activities,the contradictions between water resources in the Dinghe River Basin are becoming more intense,and the problems of ecological environment are becoming increasingly prominent.How to balance the balance between life,production,and ecological benefits of WuDing river basin is a problem that needs to be solved urgently.Therefore,the development of water resources and ecological scheduling of WuDing river basin has important theoretical and guiding significance for the sustainable development of the social economy and ecological security in the watershed.Based on hydrological diagnosis,this article used hydrological methods to calculate the control of the controlled section ecological flow of the WuDing river basin and evaluated the ecological flow.Combined with the actual situation of the WuDing river basin,different prediction models were used to predict the amount of water consolidated households,and the contradiction between the supply and demand of water resources in the basin was analyzed.Establish a reservoir ecological scheduling model,evaluate the non-inferior solution set,determine the reservoir scheduling plan.The main research results are as follows:(1)Meristive diagnosis of hydrological variability in different river sections of the Wuding River Basin,and adopt different diagnostic methods to gradually determine the hydrological mutation point of Zhao Shi kiln,Dingjiagou,and Baijiachuan section through preliminary diagnosis,detailed diagnosis,and comprehensive diagnosis.Calculate ecological flow through the monthly minimum ecological flow method and NGPRP method,and combine the Tennant method to evaluate ecological flow.Through diagnosis,the year of mutation of Zhao Shi kiln,Dingjiagou,and Baijiachuan was 1974,1970,and 1996.The four controlled sections of the dry flow of the Wudinghe River Basin(Wang Yanzhong,Zhao Shi Kiln,Dingjiagou,and Baijiachuan)in the fishing period of fish spawning were 10.46m3/s,19.78m3/s,12.56m3/s,7.55m3/s;the minimum ecological flow of general water period were 15.19m3/s,28.08m3/s,23.97m3/s,4.28m3/s.The result of the minimum ecological flow obtained by the Tennant legal evaluation before the mutation was above the "middle" level,which could meet the requirements of the ecological flow guarantee of the Wuding River Basin.After the mutation,the Tennant evaluation level of Dingjiagou and Baijiachuan’s section in the flood season were "poor",which could not meet the minimum requirements for ecological traffic protection.In the natural state of Wang Yan’s blocked face,the evaluation results of ecological flow in the flood season and non-flood season were "excellent" and "best".(2)A GM(1,1)gray prediction model,a BP neural network model and a combined prediction model based on the entropy weight method were used to predict the water demand for domestic,agricultural,industrial,construction and tertiary industries and ecology in the Wuding River basin.The amount of water resources and water conservancy facilities in the Wuding River basin were used to predict the amount of water available for different planning years,and finally the basin water supply and demand analysis is carried out.Based on the entropy weighting method,the gray prediction model was combined with BP neural network to predict the water demand in the Wuding River basin,and the results of each user’s water demand were better in the rate period,test period and comprehensive situation.The differences are small.The prediction results were 1.216 billion m3(75%),1.374 billion m3(95%)in 2025 and 1.216 billion m3(75%),1.374 billion m3(95%)in 2030 for the Wuding River basin.Combined with the water supply available in the basin,the supply and demand analysis of the Wuding River Basin show that in the planning level year of 2025,the Wuding River Basin would have water shortage of 172 million m3 and 377 million m3 in the dry and extra dry years,respectively.in the planning level year of 2030,the Wuding River Basin would reach the balance of supply and demand in the dry period with the increase of external water sources,while in the extra dry period,There was a water shortage of 0.67 billionm3 in the Wuding River basin.(3)The ecological scheduling study was conducted on the Wang Oh plug reservoir,a controlling water conservancy project in the Wuding River basin,and an ecological scheduling model of the reservoir with economic and ecological benefits as the objectives was established.The evaluation index system of multi-objective decision making was constructed by adding ecological reliability index and industrial benefit index on the basis of economic benefit index and AAPFD index.The entropy-weight-TOPSIS method was used to prefer 100 multi-objective decision-making schemes.Finalised the optimal dispatch plan for flat,dry and very dry water years.