Study On The Influence Mode Of Cascade Reservoir On Hydrological Process Of The PingShan Station And Key Hydrologic Indicators

National nature reserve of rare and endemic fish in the upper Yangtze River is national nature reserve that is the only span multiple provinces and dedicated to protected rare and endemic fish. Protected objects, including Psephurus gladius, Acipenser dabryanus, Myxocyprinus asiaticus three kinds of rare fish and Coreius guichenoti,Leptobotia elongata, Procyris rabaudi sixty-six species of endemic fish species. At present, the Xiangjiaba and Xiluodu hydropower station in the upper reaches have built hydropower, Baihetan and Wudongde hydropower stations are also carrying out preliminary work, in addition to other rivers in protected areas are also facing a lot of hydropower project development and construction. Hydroelectric projects on the reserve’s hydrological, river morphology, water quality will affect, how biological objects affected degree of protection of the refuge, and the measures taken to mitigate,respond to these influences are social hotspots. This Paper focus analysis cascade Reservoir downstream main control hydrometric station points--Pingshan station in reservoir scheduling before and after of ecological hydrological changes process,research cascade reservoir on downstream ecological hydrological of effects mode, while analysis reserves most can reaction River hydrological changes features of key hydrological indicators, helps science awareness cascade reservoir scheduling on downstream of effects, for coordination reservoir scheduling run and ecological environmental protection of relationship, and maintenance reserves natural balance provides reference.Firstly, select Pingshan, located downstream of the Xiangjiaba is selected as the object of study, through the establishment of cascade reservoir dispatching model to simulate Pingshan station’s hydrological processes, comparative analysis by IHA and RVA method before and after dispatching the Pingshan station of eco-hydrological process, summarizes and analyzes impact on downstream cascade reservoir operation mode.According to the protected fish data in the nature reserve at Pingshan station, Zhutuo station, the Cuntan station of three sites by principal component analysis and Pearsoncorrelation coefficient method calculating reserves reflect River hydrological characteristics of the analysis the key hydrological indicators.Through this study, we know that Cascade reservoir scheduling run makes downstream from March to June monthly flow rose, from July to October monthly flow declined, from November to February monthly flow maintained not variable; years maximum value flow reduced, years minimum value flow increased, and occurred time are has advanced; high pulse times reduced, lasted extended, low pulse times and lasted are substantially reduced; continuous day flow of rose, and declined rate variable small,flow reversed times reduced, this three indicators changes degree larger; the levels of average annual flow variations and hydrological changes are both small.The key hydrological indicators in protected area respectively are April, May, July,August average monthly flow, annual maximum continuous 90 day average flow and base flow index, annual minimum and maximal occurred timing, high pulse duration and frequency, low pulse frequency rise rate, fall rates and number of hydrologic reversals.