由于水电大造成的尼罗河流域河流网络连接的时空空间变化
Anthony Basooma1, Astrid Schmidt-Kloiber1, Rose Basooma2,3
1BOKU University, Institute of Hydrobiology and Aquatic Ecosystem Management, Vienna, Austria.
PloS one
|April 29, 2025
概括
尼罗河流域的水电大正在分裂河流生态系统,显著减少连接,特别是在赤道尼罗河流域. 这影响着生物多样性,需要鱼类迁徙走廊和更好的屏障监测.
科学领域:
- 河流生态 河流生态
- 水力发电发展 水力发电发展
- 保护科学 保护科学
背景情况:
- 提供了水电和水资源管理等基本服务,但破坏了河流生态系统和连接.
- 尼罗河流域的水电大数量大幅增加,引发了人们对河流网络碎片化的担忧.
- 关于尼罗河流域内河流连接和个别水影响的时空变化的知识有限.
研究的目的:
- 通过Reach连接指数 (RCI) 和网络中心性指标,评估纵向河流连接的时间和空间变化.
- 评估现有,正在建设中的和拟议的水对赤道尼罗河和蓝尼罗河流域河流网络碎片化的影响.
- 确定受影响最严重的河段,并比较两个盆地之间的连接损失程度.
主要方法:
- 利用Reach连接指数 (RCI) 和网络中心性措施来分析纵向连接变化.
- 收集了关于赤道尼罗河流域 (ENB) 的101座水 (1954-2035) 和蓝尼罗河流域 (BNB) 的19座水 (1925-2035) 的数据.
- 模拟的场景将大视为不可逾越的障碍,以评估连通性减少.
主要成果:
- 两个流域均显示平均RCI的显著下降,中段的河流段受到影响最大.
- 与蓝尼罗河流域 (BNB) 相比 (1925年的62.5%到2035年的21.35%),赤道尼罗河流域 (ENB) 的连接性下降幅度明显高 (从1954年的50.1%到2035年的18.1%).
- 在2010年至2015年期间,ENB的水急剧增加,加剧了连接性损失和威胁生物多样性.
结论:
- 越来越多的水开发,特别是在ENB地区,正在严重分散河流网络,威胁着生物多样性.
- 有效的鱼类迁徙走廊对于现有的大型水 (例如,大埃塞俄比亚文艺复兴大,卡科诺大) 减轻影响至关重要.
- 建议包括建立一个盆地范围的障碍数据库,评估通行性,并整合遥感和eDNA进行影响监测.
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