Basin hydrological modelling and forecasting of “River-Reservoir System” I： Concept and variation characteristics

The construction and operation of large-scale reservoirs have significantly altered the subsurface conditions of the river basin. The natural river system has evolved into a complex river network with multiple barriers， and the runoff shows obvious variations compared with the natural situation， which leads to significant changes in the characteristics and patterns of basin yield and confluence. Regarding the changing characteristics of the river system， the concept of “River-Reservoir System” is proposed， and the mechanism of its effect on the basin yield and confluence process is demonstrated by combining with its hydrological-hydraulic characteristics. Taking the Three Gorges Reservoir and the Jingjiang River as examples， this study quantitatively analyzes the influence of the “River-Reservoir System” on the hydrological simulation process， aiming to provide theoretical foundations and technical support for guiding scientific and refined reservoirs （group） scheduling.