齐口裂腹鱼趋流行为的水力学特性研究

过鱼设施的过鱼效果取决于能否准确理解鱼类洄游、集群行为与水力学特性之间的响应关系,能否确定洄游路线和集群区域。以西南山区河流特有的齐口裂腹鱼为例,采用Acoustic-Doppler Velocimeter测得试验水槽的流速分布,利用视频捕捉系统获得试验鱼的运动轨迹,将试验鱼的运动轨迹与不同水力因子(流速、紊动能、流速梯度)进行耦合,定量分析齐口裂腹鱼洄游、集群的水力学特性,并研究了与特定水力因子的相关性。结果表明,齐口裂腹鱼上溯运动过程中,水流方向及流速梯度体现了鱼的趋流特性,决定了鱼的上溯运动方向,而对于局部空间内鱼的游泳运动行为,紊动能也是直接的水力影响因子。这为鱼道进口位置的布置提供了科学依据。

Study on Hydraulic Characteristics of Schizothorax Prenantis Rheotaxis Behavior

The effect of fish crossing the artificial channel depends on the accurate understanding of the response relationship among migration, clustering behavior and hydraulics of fish. And it also depends on whether the migration route and the cluster area can be determined. In this paper, the schizothorax prenantis in Southwest Mountain Streams were selected as the target fishes. The velocity distribution of the experimental flume was measured by Acoustic-Doppler Velocimeter, and the motion track of the experimental fish was obtained by video capture system. By coupling the trajectory of the fish with different hydraulic factors (velocity, turbulence energy and velocity gradient), the hydraulic characteristics of migration and colonization of schizophrenic fish were quantitatively analyzed, and the correlation with specific hydraulic factors was studied. The results show that in the process of upstream motion, the velocity vector of water flow and velocity gradient reflect the characteristics of rheotaxis behavior, which determines the direction of fish upstream motion. Turbulence energy is also the direct hydraulic factor affecting the swimming behavior of fish in local space. The results can provide a scientific basis for the layout of fishway entrance.