Abstract:
Geobotanical subdivision of landcover is a baseline for many studies. The High-Low Arctic boundary is considered to be of fundamental natural importance. The wide application of different delimitation schemes in various ecological studies and climatic scenarios raises the following questions: (i) What are the common criteria to define the High and Low Arctic? (ii) Could human impact significantly change the distribution of the delimitation criteria? (iii) Is the widely accepted temperature criterion still relevant given ongoing climate change? and (iv) Could we locate the High-Low Arctic boundary by mapping these criteria derived from modern open remote sensing and climatic data? Researchers rely on common criteria for geobotanical delimitation of the Arctic. Unified circumpolar criteria are based on the structure of vegetation cover and climate, while regional specifics are reflected in the floral composition. However, the published delimitation schemes vary greatly. The disagreement in the location of geobotanical boundaries across the studies manifests in poorly comparable results. While maintaining the common principles of geobotanical subdivision, we derived the boundary between the High and Low Arctic using the most up-to-date field data and modern techniques: species distribution modeling, radar, thermal and optical satellite imagery processing, and climatic data analysis. The position of the High-Low Arctic boundary in Western Siberia was clarified and mapped. The new boundary is located 50-100 km further north compared to all the previously presented ones. Long-term anthropogenic press contributes to a change in the vegetation structure but does not noticeably affect key species ranges. A previously specified climatic criterion for the High-Low Arctic boundary accepted in scientific literature has not coincided with the boundary in Western Siberia for over 70 years. The High-Low Arctic boundary is distinctly reflected in biodiversity distribution. The presented approach is appropriate for accurate mapping of the High-Low Arctic boundary in the circumpolar extent.
摘要:
地表覆盖的地植物学细分是许多研究的基线。北极高低边界被认为具有基本的自然重要性。不同的划界方案在各种生态研究和气候情景中的广泛应用提出了以下问题:(i)定义高北极和低北极的通用标准是什么?(ii)人类影响会显着改变划界标准的分布吗?(iii)在持续的气候变化下,被广泛接受的温度标准仍然相关吗?(iv)我们能否通过绘制这些标准来定位北极的高低边界,这些标准来自现代开放的北极遥感和气候研究人员?统一的环极标准基于植被覆盖和气候的结构,而区域细节反映在花卉成分中。然而,公布的划界方案差异很大。研究中地球植物学边界位置的分歧体现在可比性差的结果中。在保持地球植物学细分的共同原则的同时,我们使用最新的野外数据和现代技术得出了北极高和低之间的边界:物种分布建模,雷达,热和光学卫星图像处理,气候数据分析。阐明并绘制了西伯利亚西部北极高低边界的位置。与以前提出的所有边界相比,新边界位于向北50-100公里处。长期的人为压力有助于植被结构的变化,但不会显着影响关键物种范围。在科学文献中接受的先前指定的北极高低边界的气候标准与西伯利亚西部的边界没有重合70多年。北极高低边界在生物多样性分布上有明显的体现。所提出的方法适用于在极地范围内准确绘制北极高低边界。