绘制世界自由流动的河流
G Grill1, B Lehner2, M Thieme3
1Department of Geography, McGill University, Montreal, Québec, Canada. guenther.grill@mail.mcgill.ca.
Nature
|May 10, 2019
概括
在全球范围内,只有37%的长河仍在自由流动,基础设施建设正在分裂重要的河流生态系统. 这项研究绘制了剩余的自由流动河流 (FFR),以帮助保护工作.
科学领域:
- 生态学
- 水文学
- 保护科学
背景情况:
- 自由流动的河流是支持生物多样性和提供基本服务的关键全球生态系统.
- 基础设施发展,特别是水,对河流连接,生态系统过程和生物多样性构成重大威胁.
研究的目的:
- 评估河流的全球连接状况,并确定剩余的自由流动河流.
- 提供旨在维护或恢复河流连接的全球和国家战略的基础.
主要方法:
- 应用了一种新方法来量化全球1200万公里的河流连接.
- 绘制地图确定了FFR,并评估了它们不间断地流向海洋的情况.
主要成果:
- 只有37%的长度超过1000公里的河流在整个长度上保持自由流动.
- 只有23%的河流不间断地流向海洋.
- 其余的FFR主要位于偏远的北极,亚马逊和刚果盆地地区,只有少数人口密地区.
结论:
- 水和水库是导致河流碎片化和连通性丧失的主要原因.
- 迫切需要全球和国家战略来维护和恢复自由流动的河流及其相关生态系统.
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