Research On Fenhe Reservoir Ecological Operation Considering Ecological Water Demand Constraint

Reservoir ecological operation,based on conventional reservoir scheduling,puts the ecological objectives into the scheduling process so as to gain the organic unity of social benefit,economic benefit and ecological benefit and seek the best combination by changing the reservoir scheduling,maximally meeting the need of water requirement of river ecosystem,and maintaining the river ecosystem healthy.This paper,taking Fenhe river as the research object,from the viewpoint of river ecosystem health,finds out the basic concept of ecological water requirements and ecological water demand calculation,connotation and classification of ecological operation of reservoirs,and build a model for Fenhe reservoir ecological operation and application.Finally it explores and analyses the research results.The research results are as follows:(1)This paper use the monthly minimum ecological runoff calculation method and frequency years from month to month distribution calculation method,calculation of Fenhe river four typical hydrological sections(Fenhe reservoir,Lan Country,Second Dam,Chai Zhuang)ecological runoff.The calculation results show that the monthly minimum ecological runoff calculation method and frequency years from month to month and calculated the ecologicalrunoff calculation method of distribution conforms to Tennant method the goal of ecological function in evaluation standard requirements.Years monthly frequency distribution method is in the month-by-month frequency method and years distribution method is proposed on the basis of a new kind of river ecological runoff calculation method.This method takes into account the river overall process and its characteristics,especially the seasonal and change.Therefore,in the reflected the variation characteristics of river natural runoff has certain advantages.Compared with monthly minimum ecological runoff calculation method,the method to calculate and determine the more conducive to ecological health,ecological runoff is more close to the natural river year situation and change.(2)According to the concepts of river ecological water requirement and composition,selection of different calculation method,calculated the different hydrology section of Fenhe river self-purification water demand,sand transport water demand,the sea water,considering the characteristics of the ecological water demand,the process of comprehensive ecological water requirement of different hydrology section of Fenhe river.(3)To meet the Fenhe Reservoir economic benefit as the goal,the lower reaches of the reservoir ecological water demand constraints,the establishment of the FS-DDDP algorithm based on the establishment of the reservoir ecological scheduling model.Taking Fenhe Reservoir as an example,different water supply schemes are set up,and the ecological scheduling scheme of Fenhe reservoir is obtained at different level years.The results of each scheme are compared and analyzed.The results show that the reservoir ecological operation in a wet year in guarantee under the premise of ecological water requirement,the ecological efficiency of the reservoir was the best,and the scheme 1 and the scheme 3 were better than the other schemes.The urban water supply andirrigation water can be fully satisfied,and the urban water supply and irrigation water were 182.5 million m3 and 84.49 million m3 respectively.The reservoir ecological operation in a median year in guarantee under the premise of ecological water requirement,the economic benefits of the reservoir was the best,and the scheme 5 was better than the other schemes.The urban water supply can be fully satisfied,the irrigation water can only be partially satisfied,and the urban water supply and irrigation water were 182.5 million m3 and 137.53 million m3 respectively.The reservoir ecological operation in a dry year in guarantee under the premise of ecological water requirement,the economic benefit of reservoir was the best,and scheme 9 was better than other schemes.The urban water supply can be fully satisfied,the irrigation water can only be partially satisfied,and the urban water supply and irrigation water were 182.5million m3 and 95.82 million m3 respectively.