VORTICITY CHARACTERISTICS OF CHINESE STURGEON SPAWNING GROUND

Since the construction of the Gezhouba Dam in 1981, it has been found that Chinese sturgeon, Acipensor sinensis, performes natural propagation annually in a narrow reach downstream close to the Gezhouba Dam site. This would allow one to better investigate what the hydraulic and morphologic conditions of a river can meet the Chinese sturgeon spawning. In this article, the absolute values of vorticity have been computed along the river cross-sections based field measuring data. The relation of the CPUEd to vorticity strength over the study area has been developed. It suggests that the proposed vorticity metric is sensitive to being able to describe the hydraulic characteristics of Chinese sturgeon spawning ground. The Chinese sturgeon spawns mainly distribute the area where the vorticity strength is larger than 0.4 s(-1).