恢复水和沉积物流通过巨型大的布可以缓解沉没的河流三角洲吗?
Samuel De Xun Chua1,2, Yuheng Yang1, G Mathias Kondolf3
1Department of Geography, National University of Singapore, Singapore 117570, Singapore.
Science advances
|May 1, 2024
概括
大型水电大通过捕获沉积物破坏河流生态系统,威胁三角洲. 减少水死存可以帮助恢复沉积物流动,并保护下游地区免受沉降.
科学领域:
- 环境科学环境科学
- 水文学的水文学
- 可再生能源是可再生的能源.
背景情况:
- 水力发电大提供可再生能源,但显著改变了河流生态系统.
- 公河是大型水下游负面影响的典范,包括沉积物饥饿和三角洲侵蚀.
- 传统的水管理策略不足以减轻这些广泛的环境影响.
研究的目的:
- 挑战大型大的传统设计,并有大量的死存储.
- 提出较小的死体储存作为减轻下游沉积物饥饿的战略.
- 调查修改水设计的潜力,以保护三角洲免受沉降和海平面上升的影响.
主要方法:
- 在各种水运行场景下,对公河沉积物负载动态的分析.
- 长期沉积物被水所捕获的建模.
- 评估死存量对下游沉积物供应的影响.
主要成果:
- 即使有乐观的沉积物排水,公河三角洲的沉积物负载恢复到仅为62.3±8.2万,远低于历史的1.06亿.
- 预计水将在至少170年内捕获沉积物,而无需为沉积物重新定向进行改造.
- 减少水设计中的死存可以显著改善下游沉积物流动.
结论:
- 目前的大型水的设计具有大量的死存储,加剧了下游沉积物的饥饿.
- 改造水或采用较小的死存储设计对于防止三角洲消失至关重要.
- 尽量减少死存储提供了一个可行的解决方案,以缓冲三角洲的沉降和相对海平面上升.
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