身体长度决定了彩虹鱼 (Oncorhynchus mykiss) 在翼后面的流动避难点
Terry R Dial1,2, Laura A Collins1, James C Liao3
1Field Research Station at Fort Missoula, Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA.
The Journal of experimental biology
|July 18, 2024
概括
任何大小的彩虹鱼都会使用流来进行流动,当流的宽度至少是鱼的长度的1.5倍时,会观察到一致的行为. 这种水力动力学研究有助于鱼类保护工作.
科学领域:
- 流体动力学 流体动力学
- 鱼类学 鱼类学 鱼类学
- 生态工程生态工程
背景情况:
- 自然溪流具有复杂的水力动力学特征,影响鱼类的行为和生存.
- 鱼类利用附着的,由流中的物体产生,用于流的逃离和潜在的能量收获.
- 了解不同鱼类大小类如何与相互作用对于保护至关重要.
研究的目的:
- 调查不同大小类的彩虹鱼 (Oncorhynchus mykiss) 的流失和能量收集行为.
- 在微息地选择中确定状特征与鱼类大小之间的关系.
- 为了评估在中游泳的能量成本和益处.
主要方法:
- 利用一个控制自由流量 (65厘米 s-1) 的水流和人工翼水来产生.
- 监控的微生态选择和游泳动力学指纹 (8厘米),parr (14厘米) 和成年 (22厘米) 彩虹鱼.
- 采用时间分辨率粒子图像速度测量 (PIV) 来测量旋时的流场.
主要成果:
- 所有彩虹鱼大小类优先占据自由流上的 vortices.
- 当的宽度与鱼的长度比率 (WV:LF) 为≥1.5.5时,有效的流量逃离发生.
- 在旋流中,鱼的波长和斯特劳哈数增加,尾巴跳动频率降低,表明能量成本降低.
- 在17%的试验中观察到能量收集行为.
结论:
- 鱼的尺寸相对于的尺寸是成功流水捕捞的关键因素.
- 旋为彩虹鱼的游泳提供了能量优势,可能降低代谢成本.
- 这些发现可以为沿海恢复和鱼道设计提供信息,以加强鱼类的保护和穿越.
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