河流游泳池作为可达规模的热调节器
Andrew W Tranmer1, Andrea Bertagnoli1, Aaron Hurst2
1Center for Ecohydraulics Research, Department of Civil and Environmental Engineering, University of Idaho, 322 E. Front St., Boise, ID 83702, USA.
The Science of the total environment
|December 13, 2024
概括
河流恢复创造了深水池,热层分层,缓冲温暖的夏季温度. 这些游泳池改善了下游水域的水生生物条件,尽管它们无法消除所有热应激.
科学领域:
- 环境科学 环境科学
- 河流生态 河流生态
- 恢复生态学 恢复生态学
背景情况:
- 由于气候变化和人类活动,河流温度正在上升,这给水生生态系统带来了压力.
- 河流恢复工作的目的是通过调节温度和创造冷水避难所来减轻热应激.
- 了解恢复的热影响对于水生息地管理至关重要.
研究的目的:
- 评估河流恢复在温和水温中的有效性.
- 为了比较在恢复前和之后的热条件,受到hyporheic排放和池分层的影响.
- 评估恢复的河流段的局部和范围范围的热缓冲能力.
主要方法:
- 使用现场数据收集和数值模拟来分析水温.
- 研究了低温排放和地下水对地表水温的影响.
- 研究了挖掘池中的热分层及其与池深度的关系.
主要成果:
- 低气体排放对地表水温的影响很小,因为水体体积小.
- 挖掘的游泳池表现出热分层,产生高达4.6°C的温度差异.
- 较深的池在较长时间内保持温度低于鱼死亡值.
- 恢复导致下游最大每日水温下降3°C,而恢复前的温度上升1.5°C.
结论:
- 挖掘的游泳池通过热分层有效地创建局部的冷水避难所.
- 分层池的累积效应提供了可达规模的热缓冲,改善了下游条件.
- 虽然恢复可以改善热条件,但在长时间的温暖时期,它可能无法完全缓解上游的热应力.
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