高低北极边界:它是如何确定的,它位于哪里?
Ksenia A Ermokhina1, Anna I Terskaia2,3, Tatiana Yu Ivleva1
1A.N. Severtsov Institute of Ecology and Evolution Russian Academy of Sciences Moscow Russia.
Ecology and evolution
|October 2, 2023
概括
使用现代数据重新定义了高低北极边界,揭示了西西伯利亚的新北极. 这一边界对于理解北极生物多样性至关重要,并清楚地反映在物种分布模式中.
科学领域:
- 生态生态学 生态生态学
- 生物地理学是生物地理学.
- 遥感 遥感 遥感 遥感
背景情况:
- 陆地覆盖的地质植物分类对于北极生态研究至关重要.
- 现有的划分高北极和低北极边界的方案有很大的差异,导致结果不太可比.
- 由于气候变化和人类的影响,传统标准,特别是温度的相关性受到质疑.
研究的目的:
- 调查定义高北极和低北极边界的共同标准.
- 评估人类活动对边界划分标准的影响.
- 为了确定温度作为高低北极边界标准的持续相关性.
- 用现代遥感和气候数据绘制高低北极边界的地图.
主要方法:
- 利用了物种分布模型.
- 处理了雷达,热和光学卫星图像.
- 分析了气候数据.
- 纳入最新的实地数据,用于地质植物学分类.
主要成果:
- 澄清和绘制了西西伯利亚的高低北极边界.
- 新定义的边界位于比以前建立的边界更北的50-100公里处.
- 人类产生的压力改变了植被结构,但没有显著影响关键物种的范围.
- 70多年来,高低北极边界的公认温度标准与西西伯利亚的实际边界不一致.
结论:
- 高低北极的边界在生物多样性分布中得到了明显的反映.
- 开发的方法适用于在环极地区准确地绘制高低北极边界.
- 对高低北极边界的修订理解对于未来的生态和气候研究至关重要.
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