的演变导致了美国河流的碎片化
Rachel A Spinti1, Laura E Condon2, Jun Zhang3
1Hydrology and Atmospheric Sciences, University of Arizona, 1133 James E. Rogers Way, Tucson, 85721, AZ, USA. rspinti@arizona.edu.
Nature communications
|June 28, 2023
概括
中等大小的水显著地分裂了美国的河流,扭转了自然模式. 这些结构不成比例地影响水生息地,创造了许多短河片段.
科学领域:
- 环境科学 环境科学
- 水文学的水文学
- 生态生态学 生态生态学
背景情况:
- 众所周知,水减少了河流连接,但全球研究往往忽视了中型结构.
- 在美国,中型水占主要人为结构的96%,水库储量的48%,但在全球数据库中没有.
研究的目的:
- 为了进行一项全国性的评估,对美国水随着时间的推移造成的河流碎片化进行评估.
- 评估中型水对河流连接和息地碎片化的影响.
主要方法:
- 分析了全国5万多个大的库存.
- 评估人类造成的河流分叉的演变.
- 由大造成的河流碎片的量化,按尺寸区分.
主要成果:
- 在全国范围内,中等大小的水负责73%的人为创造的河流碎片.
- 这些水不成比例地导致短河段 (不到10公里),对水生息地产生负面影响.
- 堤建设扭转了历史上的河流碎片化模式,潮湿的流域现在是最碎片化的.
结论:
- 中等大小的水在美国的河流碎片化中发挥着关键作用,超过了较大的结构的影响.
- 该研究强调了大规模筑对生态的影响,特别是对水生生态系统的影响.
- 美国目前的碎片化模式是由人类发展驱动的,与自然干旱盆地碎片化形成鲜明对比.
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