双模树生长气候反应模式的生理意义
Ulf Büntgen1,2,3, Jan Esper4,5
1Department of Geography, University of Cambridge, Cambridge, CB2 3EN, UK. ulf.buentgen@geog.cam.ac.uk.
International journal of biometeorology
|May 30, 2024
概括
微弱的树木生长与气候相关性,尤其是夏季的气温,并不能否定它们对树木生长的生理重要性. 干燥气候学家需要超越统计学意义的机械理解,才能准确地解释气候信号.
科学领域:
- 登德罗年代学 登德罗年代学
- 气候科学 气候科学
- 植物生理学 植物生理学
背景情况:
- 相关系数是识别气候信号的标准,用于像树环这样的代理档案中.
- 对于寒冷的季节,微不足道的生长气候相关性是常见的,但对于温暖的季节,它们的解释需要细微差别.
研究的目的:
- 为了研究树木生长 (最大松木密度) 和不同欧洲树林线地点的气候变量之间的关系.
- 挑战假设微不足道的统计相关性否定气候因素的生理重要性,特别是夏季温度,树环形成 (树环生成).
主要方法:
- 分析了从北斯堪的纳维亚到西班牙南部的十个树林线地点的最大松木密度记录.
- 检查月度生长气候相关性,重点关注温度的影响,特别是超过5°C的最低温度 ("生物零").
主要成果:
- 每月生长-气候相关性从单模转变为双模模式,植被周期较长,较温暖.
- 当最低温度超过5°C时,出现了统计学上显著的关系.
- 在地中海地区的高夏季气温与微不足道的相关性并不等同于缺乏生理相关性.
结论:
- 仅仅是统计学意义是不够的;对于解释树木生长与气候关系至关重要的是机械的理解.
- 由于某些地区的高夏季气温没有统计学意义,但这并不能否定它们对树环形成的生理重要性.
- 树林气候学家在解释树环数据中的气候信号时必须考虑生长季节的长度和温度值.
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