竖缝式鱼道(Vertical Slot Fishway,VSF)作为一种协助上溯性鱼类恢复其洄游通道的生态补偿措施,受到广泛关注.其过鱼效果与VSF的水力特性和鱼类的游泳运动能力密切相关.因而,良好的VSF设计应保证池室内的水力特性与过鱼对象的游泳运动能力相适宜.本文选取上溯性鱼类鳙鱼和草鱼为研究对象,将VSF池室内水力因子空间分布与鱼类运动轨迹相叠加,定量分析了鳙鱼和草鱼在上溯过程中的运动特性、水力偏好以及鱼类运动轨迹与特定水力因子的相关程度.试验结果表明:在流量为0.135 m3/s的VSF池室内,两种鱼喜好在紊动能为0.02～ 0.035 m2/s2、流速为0.16 ～ 0.4 m/s、紊动耗散率为0.02 ～ 0.04 m2/s3、应变率为2～3.5s-1的范围内运动.鳙鱼和草鱼在不同水力区域内的上溯时间与紊动能、流速相关性较大;水流流速矢量体现鱼的趋流特性,决定了鱼的上溯方向,而对于局部空间内鱼的游泳运动行为,紊动能可能是影响更直接的水力因子.%The vertical slot fishway (VSF),which can be viewed as an ecological compensation measure,plays a major role in enabling anadromous fish migration,which has received extensive attention.The fishway passage efficiency is closely related to the VSF hydraulic characteristics and fish's swimming capability.Therefore,an excellent VSF design should be suitable between the hydraulic characteristics of VSF and the fish's swimming capability.Taking two anadromous fishes,Ctenopharyngodon idellus and Aristichthys nobilis,as an example,this paper quantitatively analyzed the fishes' movement characteristics,the preferred hydraulic ranges and the relevance of hydraulic factors and fish trajectories by combined the spatial distribution of hydraulic factors with fish trajectories in VSF.The results show that the preferred ranges of turbulent kinetic energy,velocity,turbulent dissipation rate and strain rate are 0.02-0.035 m2/s2,0.16-0.4 m/s,0.02-0.04 m2/s3 and 2-3.5 s-1,respectively with the flow of 0.135 m3/s in VSF.The times swimming upstream of the two fishes in different water areas are greatly associated with turbulent kinetic energy and velocity.In our study,the flow velocity,as a vector reflecting the rheotaxis of fish,determines the movement of fish,but their swimming behavior in local water area is mainly determined by turbulent kinetic energy.
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