Impact of the Cascaded Reservoirs and the Tributaries Confluence on the Eco-hydrology of the Reserve in the Upper Reaches of Yangtze River

摘要

For studying the impacts of the tributaries confluence on the hydrological processes in the downstream reaches of the four cascaded reservoirs in the downstream of Jinshajiang River, this paper simulated the daily discharge at the outlet of the cascaded reservoirs and along the reserve mainstream in typical years with the operation programming of the reserve and MIKE11 hydrodynamic model, and eco-hydrology indicators were selected and calculated by IHA to quantify the hydrology process. The result showed that at Xiangjiaba Gauge Station discharge on April and May increased by about 100%, the discharge in low flow year decreased by 50% and the timing of annual 1-day minimum discharge has significantly alteration. The confluence of Minjiang River could effectively mitigate the impacts of the cascaded reservoirs on eco-hydrology of the downstream of the confluence, but the mitigation of others three tributaries were not significant. Moreover the pre-flood high flow in the downstream of the Minjiang River confluence increased by 50%, and other indicators alteration were not significant.