Abstract: A three-dimensional mathematical model of the flow at Chinese sturgeon spawning ground was established. The flow condition in the presence of different dispatching operation modes of Gezhouba power station was simulated by this model. The regional scale of water depth, bottom velocity and the superposition of the two of the area suitable for Chinese sturgeon spawning in the downstream near the Gezhouba Project was analyzed. The influence of Gezhouba Project dispatching on the flow condition of Chinese sturgeon spawning ground was studied, and measures of improving the flow condition of Chinese sturgeon spawning ground were discussed. The results show that when the discharge of Gezhouba Project varies in the range of 15 000-6 000 m³/s, the flow area suitable for Chinese sturgeon spawning decreases accordingly with the reducing of discharge; when the discharge is 6 000 m³/s, if all the flow is discharged by Dajiang Powerplant, it will be beneficial to increase the suitable flow area for Chinese sturgeon spawning.

Key words: Gezhouba Project, Chinese sturgeon, spawning ground, dispatching, flow condition