New potential of old proxies: Using wood anatomy to help unravel the complex interplay of tree growth and climate in boreal forest

旧代理的新潜力：利用木材解剖学帮助揭示北方森林中树木生长和气候的复杂相互作用

• 批准号: 254664299
• 负责人: Professor Dr. Martin Wilmking, Ph.D.
• 金额: --
• 依托单位: Arbeitsgruppe Landschaftsökologie und Ökosystemdynamik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/254664299?language=en
• 关键词: New; potential; old; proxies; Using

Boreal forests are the worlds largest land biome, tightly coupled to the global climate system through albedo changes and carbon dynamics. However, boreal forests are undergoing complex ecological changes, showing increasing signs of non-linear behaviour and thus have been identified as a policy relevant tipping point in the global climate system. Due to the tight coupling between tree-growth in boreal forests and climate, these trees have been extensively used to reconstruct past climate variations. But it is increasingly unclear, whether these reconstructions and future growth projections are reliable, because the influence of recent climate change on tree growth seems to strongly vary in time. This has been termed the divergence effect in dendroclimatology and has recently led to widespread boreal browning, or growth decreases with warming temperatures. Their reasons and responsible mechanisms are hotly contested and so far unresolved, because we are lacking information on environmental controls on xylogenesis in general and their temporal and spatial variations in boreal forests in particular. Here we propose to narrow this knowledge gap by applying a combination of classical dendrochronological and new wood anatomical approaches. From each tree, we will develop 13 proxy time series (ranging from traditional annual rind width, via density, to cell anatomical time series). This combination is state-of-the-art and will allow resolving intra-annual dynamics of growth processes and promises increased understanding of the processes leading to the divergence effect and boreal browning. As model systems, we have chosen Picea glauca, an important boreal North American tree species with strong prevalence to browning and Pinus sylvestris, an important Eurasian tree species showing less prevalence to browning. We will work along spatial gradients of increasing continentality to cover the naturally occurring climatic variability at the northern distribution edge of each species (eleven sites in total), using mainly available tree cores samples with some additional sampling. Our work program is divided into three related work packages: 1) Field and laboratory work, 2) Analyses of spatio-temporal pattern of browning, 3) The effects of extreme climatic events and physiological thresholds on xylogenesis. We will synthesize our results with a projection of future growth performance of both species at their northern species limit, which seems far more complex than simple species advance northwards with warming climate.

北方森林是世界上最大的土地生物群落，通过反照率变化和碳动态与​​全球气候系统紧密结合。但是，北方森林正在经历复杂的生态变化，显示出越来越多的非线性行为迹象，因此已被确定为全球气候系统中的政策相关临界点。由于北方森林和气候中树木生长之间的紧密耦合，这些树已被广泛用于重建过去的气候变化。但是目前尚不清楚，这些重建和未来的增长预测是否可靠，因为最近气候变化对树木生长的影响似乎在时间上有很大变化。这已被称为树突气候学中的差异效应，最近导致了广泛的北方褐变，或者随着温度变暖而降低生长。他们的原因和负责任的机制是激烈的争论，迄今尚未解决，因为我们缺乏有关木制发生的环境控制的信息，尤其是它们在北方森林中的时间和空间变化。在这里，我们建议通过应用经典的树突年代学和新木材解剖方法的组合来缩小这一知识差距。从每棵树中，我们将开发13个代理时间序列（从传统的年度宽度宽度，密度到细胞解剖时间序列）。这种组合是最先进的，将允许解决增长过程的年度动力学，并承诺对导致差异效应和北方褐变的过程的更多理解。作为模型系统，我们选择了Picea Glauca，这是一种重要的北美树种，具有强烈的褐变和Pinus sylvestris，这是一种重要的欧亚树种，显示出对褐变的流行程度较小。我们将沿着增加大陆性的空间梯度进行工作，以覆盖每个物种北部分布边缘（总共11个地点）的天然气候变异性，主要使用一些其他采样的样品。我们的工作计划分为三个相关的工作包：1）现场和实验室工作，2）褐变时空模式的分析，3）极端气候事件和生理阈值对木制发生的影响。我们将通过在其北部物种限制下对两种物种的未来增长性能的预测进行综合，这似乎比简单的物种在温暖的气候下向北前进要复杂得多。

项目成果

Environment drives spatiotemporal patterns of clonality in white spruce (Picea glauca) in Alaska

环境驱动阿拉斯加白云杉（Picea glauca）克隆性的时空模式

• DOI: 10.1139/cjfr-2018-0234
• 发表时间: 2018
• 期刊: Canadian Journal of Forest Research
• 影响因子: 2.2
• 作者: Würth DG;Eusemann P;Trouillier M;Burras A;Burger A;Wilmking M;Roland CA;Juday GP;Schnittler M
• 通讯作者: Schnittler M

High frequency growth variability of White spruce clones does not differ from non-clonal trees at Alaskan treelines

白云杉克隆的高频生长变异性与阿拉斯加林线的非克隆树没有差异

• DOI: 10.1016/j.dendro.2017.05.005
• 发表时间: 2017
• 期刊: Dendrochronologia
• 影响因子: 3
• 作者: Wilmking M;Buras A;Eusemann P;Schnittler M;Trouillier M;Würth DG;Lange J;Maaten- Theunissen M van der;Juday GP
• 通讯作者: Juday GP