流速和鱼类相互作用的边界效应
Gloria Mozzi1,2, Claudio Comoglio3, Costantino Manes3
1CMCC Foundation - Euro-Mediterranean Center on Climate Change, Venice, Italy. gloria.mozzi@cmcc.it.
Scientific reports
|August 27, 2025
概括
环境流动条件和边界改变了鱼群的形成. 随着流量增加,鱼类从并排到排列游泳, 尤其是在墙壁附近,
科学领域:
- 动物行为
- 水力学
- 生态学
背景情况:
- 鱼群中的集体运动对于生存至关重要,
- 由于息地碎片化,淡水迁徙鱼种群正在减少.
- 关于环境因素如何影响鱼类的相互作用和集体运动的数据有限.
研究的目的:
- 调查流速和边界近距离如何影响鱼对集体运动的协调规则.
- 了解环境线索对河流鱼类交互动态的影响.
主要方法:
- 采用缩小方法,研究意大利鱼 (Telestes muticellus) 作为最小的群体单位.
- 在一个封闭的开放通道流中追踪鱼类的移动,通过三个散装流速 (2,4,7 BL/s) 和四个空间区域.
- 分析了与流量和边界近距离相关的冲时间,形成变化,速度合和响应时间.
主要成果:
- 鱼的时间与流速不变,但随着流量增加,鱼类的形成从并排转移到直线,特别是在墙壁附近.
- 在短距离 (<6 BL) 时速度合更强,在各种流量条件下稳定.
- 纵向反应 (约0.5秒) 是不变的和对称的,而侧向反应,主要是从后面到前面的鱼,随着流量增加而加快.
- 纵向协调发生在墙壁附近和中心,而横向合则在中心达到峰值,并随着流动而加剧.
结论:
- 物理环境,包括流速和边界,极大地影响了河流鱼类的协调策略.
- 这些发现为设计有效的鱼类通道解决方案和改善鱼类移动模型提供了经验洞察力.
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