玉曲河流域裂腹鱼类游泳能力及其在鱼道设计中的应用

Swimming Ability of Schizothorax in the Yuqu River Basin and Its Application in the Design of Fish Passage Facilities

探究玉曲河流域裂腹鱼类的游泳能力,为过鱼设施建设和鱼类游泳行为学提供基础参数。以该流域优势种怒江裂腹鱼(Schizothorax nukiangensis)、贡山裂腹鱼(S.gongshanensis)为研究对象,在野外现场通过游泳能力测试水槽对裂腹鱼的感应流速、临界游泳速度、突进游泳速度及持续游泳速度、耐久游泳速度进行测定。结果表明,怒江裂腹鱼和贡山裂腹鱼的绝对感应流速相近,分别为(0.18±0.01)m/s和(0.18±0.06)m/s,绝对临界游泳速度分别为(1.05±0.12)m/s和(1.11±0.14)m/s,绝对突进游泳速度分别为(1.45±0.26)m/s和(1.40±0.21)m/s,相对临界游泳速度分别为(8.47±0.95)BL/s和(9.21±2.45)BL/s;二者的相对突进游泳速度均突破了10倍体长(BL),分别为(11.90±2.31)BL/s和(10.80±3.16)BL/s;怒江裂腹鱼和贡山裂腹鱼最大持续游泳速度均为0.63 m/s,最大耐久游泳速度分别为0.93 m/s和0.73 m/s。当以此2种裂腹鱼为主要过鱼对象时,建议鱼道入口及竖缝处流速为1.05~1.40 m/s,过鱼设施内部整体平均流速设计为0.24~1.05 m/s,休息池主流流速为0.18~1.05 m/s。研究结果可为西藏玉曲河流域鱼类资源保护及过鱼设施设计提供参考。

In this study,the dominant species in the Yuqu River basin,Schizothorax nukiangensis and Schizothorax gongshanensis,were selected for research.Swimming capability was assessed by measuring induction flow velocity,critical swimming speed,burst swimming speed,sustainable swimming speed and endurance swimming speed.The objective of the study was to provide basic parameters for fishway design.In June 2021,the test fish were collected in Yuqu River,with a body length range of 7.9-22.5 cm and body weight range of 5.3-145.0 g for S.nukiangensis and of 8.1-21.4 cm and 9.9-135.6 g for S.gongshanensis.After acclimation,the swimming ability of the fish were tested in an open flume using the stepped velocity method.The absolute induction velocities of S.nukiangensis and S.gongshanensis were similar,with values of(0.18±0.01)m/s and(0.18±0.06)m/s,respectively.The absolute critical swimming speeds of S.nukiangensis and S.gongshanensis were(1.05±0.12)m/s and(1.11±0.14)m/s,respectively,and their respective absolute burst swimming speeds were(1.45±0.26)m/s and(1.40±0.21)m/s.The respective relative critical swimming speeds were(8.47±0.95)BL/s and(9.21±2.45)BL/s and the respective relative burst swimming speeds were(11.90±2.31)BL/s and(10.80±3.16)BL/s,both exceeding 10 times their body length.The measured maximum sustainable swimming speeds of S.nukiangensis and S.gongshanensis were both 0.63 m/s,and the maximum endurance swimming speeds of S.nukiangensis and S.gongshanensis were 0.93 m/s and 0.73 m/s,respectively.When S.nukiangensis and S.gongshanensis are selected as target fish species for a fish passage,the velocities at the entrance and vertical slots should be 1.05-1.40 m/s,the average velocity inside the fish passage should be 0.24-1.05 m/s,and the velocity in the resting pools should be 0.18-1.05 m/s.Our results provide a reference for designing fish passages in the Yuqu River basin of Tibet,and is important for fish resource protection.