福建省闽江流域鲈鱼游泳能力试验研究

Experimental Research on the Swimming Ability of Lateolabrax Japonicus in Minjiang River Basin,Fujian Province

鱼类游泳能力是鱼道工程设计的重要参数之一,是鱼类在鱼道中是否成功洄游的关键依据。以闽江流域鲈鱼的感应流速、临界流速、特征流速作为研究对象,在试验室明渠玻璃水槽中利用流速递增法等方法进行测量。通过试验首次得出闽江流域鲈鱼的特征流速,即相对感应流速、相对临界流速、相对爆发流速平均值分别为0.88、2.29、2.65 BL/s(BL为体长);揭示了闽江流域与长江流域鲈鱼的差异性,即闽江流域鲈鱼的相对临界流速略高、相对爆发流速明显较高。基于试验数据对感应流速计算公式进行改进,首次提出总感应流速应为基础感应流速与体长线性增长流速值之和,并推得闽江鲈鱼基础感应流速为0.0023 m/s。

The swimming ability of fish is one of the important parameters in fishway engineering design and the key basis for successful fish migration in fishway.The induced velocity,critical velocity and burst velocity of Lateolabrax japonicus in Minjiang River Basin of Fujian Province are studied.The experiment is conducted in an open channel glass flume by using velocity gradient method.The characteristic velocity of lateolabrax japonicus in Minjiang River Basin is obtained for the first time,i.e.the mean values of relative induced velocity,relative critical velocity and relative burst velocity are 0.88,2.29 and 2.65 BL/s(BL:Body length),respectively.This study reveals the difference between lateolabrax japonicus in Minjiang River Basin and Yangtze River Basin.The relative critical velocity of the lateolabrax japonicus in the Minjiang River Basin is slightly higher than that in the Yangtze River Basin,and the relative burst velocity of the lateolabrax japonicus in the Minjiang River Basin is obviously higher than that in the Yangtze River Basin.The formula of induced velocity is improved based on the experimental data.It is firstly proposed that the total induced velocity be divided into the base part and the body length increasing part,and the basic induction velocity of Minjiang lateolabrax japonicus is 0.0023 m/s..