摘要
该研究测试并分析了澜沧江5种鱼类(体长bl的范围0.095~0.342 m)的感应流速。测试方法:首先测量鱼的长度,然后将其放于鱼类行为学装置内的游泳区中,并使其适应2 h。然后让鱼的头部朝着游泳区后端,以递增流速法调整装置内水流速度。当鱼类调转方向运动时,记录此时装置内水流速度,该水流速度即为鱼类感应流速。研究结果:1)在水温为11.1~22.6℃条件下,鱼类感应流速范围为(0.40~1.18)bl/s,即(0.07~0.23)m/s;2)鱼类相对感应流速和体长总体呈负相关关系,鱼类绝对感应流速和体长总体呈正相关关系,该相关关系对于较难捕获测试样本或仅可捕获极个别样本的鱼类游泳特性的定性预测研究具有一定指导作用;3)拟合了趋流率与水流速度的相关关系,可为寻求满足鱼类游泳需求和工程流速设计上的平衡提供参考,若仅考虑过鱼设施运行效率,则澜沧江上游某水电工程过鱼设施内最低设计流速至少为0.2 m/s。该研究结果可为鱼类行为学提供基础资料并为过鱼设施流速设计提供参考。
There is a global boom in dams.Although dams bring a huge economic benefit,they obstruct fish migrations and gene exchange.Fish passages are being designed and constructed to mitigate the influence of the dams on fish migration and gene exchange.Fish behavior researches are useful to the design of fish passages.A large amount of research about critical swimming speed and burst speed,which were related to velocity design in the high velocity region of fish passages such as the entrance,was reported worldwide.However the reports about velocity design in the low velocity region of fish passages were limited.To study fish behavior and provide information for the velocity design in the low velocity region,induced flow speed of 5 fishes in the Lancang River was investigated with the fish behavior measurement equipment and a stepped velocity test was carried out in spring when fish migrated.Before testing,fish body length was measured and the test fish was allowed to adapt to experimental conditions at 0.5 bl/s（bl meant body length of fish） for 2 h.At the initial flow velocity（approximately 0.06 m/s）,the fish was nearly motionless along the flow direction.The water velocity was increased by approximately 0.01 m/s at 5 s interval and,when the fish was no longer able to hold station and began to swim actively,the flow velocity was reported as induced flow speed.Results included：1） The induced flow speed of the fish ranged from 0.40 to 1.18 bl/s（or from 0.07 to 0.23 m/s） at 11.1-22.6 ℃,which was similar to other references（0.4-1.5 bl/s or 0.05-0.15 m/s）.2） Lateral line receptors detected small changes in flow,and swimming was induced in fish when the stimulus from lateral line receptors was sufficient.The relatively induced flow speed（bl/s） was negatively correlated with fish body length and the absolutely induced flow speed（m/s） was positively correlated with fish body length,whether each species was considered individually or all species were considered together.The above relationships were consistent to both the relationship between critical swimming speed and body length,and the relationship between burst speed and body length.The relationship could be used to forecast swimming performance of fishes that were captured with difficulty or had small quantity.3） Overmuch decreasing or increasing the designed velocity of fish passages would increase the difficulties for the engineering design and increase the cost for construction.The relationship between percentage of fish swimming trend and flow speed was obtained in this study,which could provide the reference to balance the fish demand and flow design.Based on the data of fish induced flow speed,the designed minimum velocity of the fish passages should be more than 0.2 m/s in order that 95% of fish could pass the passages successfully,if both the difficulties for the engineering design and the cost of construction were neglected,and if the effectiveness of fish passages was considered uniquely.The release site for the fish lifting machine and fish transport boats was set in the upstream,far away the dam site.If the velocity at the release site was too low,the fish lost orientation even went back to the downstream,resulting in the fail of fish passages.Therefore,the site where the velocity is higher than fish induced flow speed should be selected for releasing fish.The principle can be also applied to the selection of exit site in fish passages.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2018年第2期176-181,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金(51609155,51609157)、中国电建集团昆明勘测设计研究院有限公司项目(HD2015/S12)、中国电力建设股份有限公司项目(DJ-ZDXM-2014-04)、中国电建集团贵阳勘测设计研究院有限公司“水电工程过鱼设施关键技术研究”子课题“鱼类游泳能力测试及趋流性实验”.
关键词
流速
设施
水力学
游泳能力
游泳特性
趋流性
flow velocity
facilities
hydrodynamics
swimming capability
swimming performance
rheotaxis
