湖泊中的多变异极端
R Iestyn Woolway1, Yan Tong2, Lian Feng2
1School of Ocean Sciences, Bangor University, Anglesey, Wales, UK. iestyn.woolway@bangor.ac.uk.
Nature communications
|May 29, 2024
概括
许多湖泊面临越来越多的极端条件,如藻类繁殖,热浪和低水位. 这项研究发现,75%的湖泊经历了至少两次并发的极端事件,突出了对湖泊健康的日益增长的威胁.
科学领域:
- 环境科学 环境科学
- 临界技术 临界技术
- 遥感 遥感 遥感 遥感
背景情况:
- 湖内极端条件对水生生态系统构成重大威胁.
- 了解多个湖泊极端的同时发生和趋势对于有效管理至关重要.
研究的目的:
- 自20世纪80年代以来,在2724个湖泊中调查多个湖泊极端事件的变化,包括藻类繁殖,湖泊热浪和低湖泊水位.
- 为了确定经历这些极端的同时增加的地区.
主要方法:
- 利用卫星观测分析藻类繁殖,湖泊热浪和低湖泊水位的趋势.
- 对受花影响的湖泊进行了集中分析,以评估并发极端事件的频率.
主要成果:
- 75%的研究湖泊显示至少有两种极端类型的同时增加 (27%是一个显著的增加).
- 25%的湖泊经历了所有三个极端的频率增加 (5%的显著增加).
- 在农业肥料使用增加,湖泊变暖和水资源供应减少的地区,观察到的增幅最大.
结论:
- 极端的湖泊变得越来越频繁,并且经常同时发生.
- 未来的研究必须优先考虑了解这些极端结合的影响.
- 对湖泊极端的仔细考虑对于未来的环境风险评估至关重要.
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