新出现的趋势是,在尤拉山脉较高的海拔地区,春季对树的损害增加:来自树环数据的证据
Yann Vitasse1,2, Lynsay Spafford1,3, Joanna Reim1
1Swiss Federal Institute for Forest, Snow and Landscape Research WSL, 8903, Birmensdorf, Switzerland.
The New phytologist
|August 19, 2025
概括
晚春 (LSF) 对森林构成重大威胁. 树环显示瑞士树林中LSF损害日益增加,突显了气候变化风险.
科学领域:
- 森林生态 森林生态
- 气候变化影响气候变化的影响.
- 登德罗年代学 登德罗年代学
背景情况:
- 晚春 (LSF) 事件对树木生长和森林生产力产生负面影响.
- 全球变暖可能会通过改变植被现象学和的时间来加剧LSF风险.
- 使用气候和现象学数据重建历史的LSF模式是很困难的.
研究的目的:
- 重建过去的LSF事件并评估它们对欧洲树的影响.
- 开发一种新的树环方法来识别LSF影响.
- 分析瑞士尤拉山脉LSF风险的趋势及其与气候变化的关系.
主要方法:
- 利用现象学模型,高分辨率的气候数据,以及九十年来从欧洲树和挪威杉树的树环分析.
- 开发了一种比较的树环指标,以区分LSF效应与背景气候信号.
- 分析了叶子脱落时间和最后一次的日期之间的时间关系.
主要成果:
- 自1991年以来,已经确定了6个有害的LSF事件,其频率是长期速度的两倍.
- 在过去二十年中,在高海拔地区经常观察到负安全边际 (最后之前的叶子脱落).
- 没有发现滞后效应,表明欧洲木可以耐受偶尔的.
结论:
- 树环作为可靠的生物指标,用于重建过去的LSF事件,克服传统数据的局限性.
- 近几十年来,越来越多的LSF频率引发了人们对山区森林在气候变化下的未来弹性问题的担忧.
- 这项研究提供了关于森林在气候变化中的极端天气事件的脆弱性的关键见解.
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