在成熟树冠的垂直光梯度沿线均的碳储备动态
Cedric Zahnd1,2, Miro Zehnder1, Matthias Arend1,3
1Department of Environmental Sciences-Botany, University of Basel, Schönbeinstrasse 6, 4056 Basel, Switzerland.
Tree physiology
|January 10, 2024
概括
树冠光度梯度对非结构性碳水化合物 (NSC) 动态的影响最小. 大多数物种在阳光和阴影的树枝中都显示出类似的NSC水平,这表明整个树的碳储量通常是代表性的.
科学领域:
- 植物生理学 植物生理学
- 森林生态 森林生态
- 碳循环是碳循环的过程.
背景情况:
- 非结构性碳水化合物 (NSC) 的树内可变性是准确碳平衡计算的关键.
- 垂直光梯度对分支NSC度和动态的影响仍然不太清楚.
研究的目的:
- 调查冠状内部光梯度如何影响温带树木中的NSC度和季节动态.
- 评估跨年气候变化对NSC储存和动态的影响.
主要方法:
- 测量了NSC度,辐射和叶子特征,在阳光照射 (最上层) 和阴影 (最下层) 的九种温带树种的树枝上.
- 在整个生长季节进行了高分辨率测量,使用了另外两年气候对比的数据.
- 分析了季节性NSC动态,季末度和叶子特征适应.
主要成果:
- 大多数物种在阳光和阴影分支之间表现出类似的季节性NSC动态和度,尽管有光度梯度.
- 叶子特征适应 (特定的叶子区域,光合作用特征) 补偿了不同的光可用性.
- 在环状多孔物种 (Quercus, Fraxinus) 的下层分支中观察到较慢的粉补充;季末的NSC在树冠位置和年份中是一致的,除了干旱压力下的Fagus sylvatica.
结论:
- 树内NSC测量通常代表整个树冠,这表明微气候梯度的影响有限.
- 树木碳储备的动态似乎很大程度上不敏感于年度间气候变化,除了严重的碳赤字.
- 叶子水平的适应在缓冲NSC对树冠内光度梯度的反应中起着重要作用.
相关概念视频
Primary and Secondary Growth in Roots and Shoots
57.2K
Vascular plants, which account for over 90% of the Earth’s vegetation, all undergo primary growth—which lengthens roots and shoots. Many land plants, notably woody plants, also undergo secondary growth—which thickens roots and shoots.
57.2K
Xylem and Transpiration-driven Transport of Resources
23.9K
The xylem of vascular plants distributes water and dissolved minerals that are taken up by the roots to the rest of the plant. The cells that transport xylem sap are dead upon maturity, and the movement of xylem sap is a passive process.
23.9K
Meristems and Plant Growth
45.9K
Plants grow throughout their lives; this is called indeterminate growth, and it distinguishes plants from most animals. Although certain parts of plants stop growing (e.g., leaves and flowers), others grow continuously—like roots and stems.
45.9K
Energy Line and Hydraulic Gradient Line
1.1K
Based on Bernoulli's equation, the energy line (EL) and hydraulic grade line (HGL) provide graphical representations of energy distribution in a fluid flow system. For steady, incompressible, inviscid flows, Bernoulli's equation is expressed as:
1.1K
Survival Tree
86
Survival trees are a non-parametric method used in survival analysis to model the relationship between a set of covariates and the time until an event of interest occurs, often referred to as the "time-to-event" or "survival time." This method is particularly useful when dealing with censored data, where the event has not occurred for some individuals by the end of the study period, or when the exact time of the event is unknown.
Building a Survival Tree
Constructing a...
Building a Survival Tree
Constructing a...
86
Ecological Succession
17.3K
Ecological succession is influenced by the processes of facilitation, inhibition, and toleration. Facilitation occurs when early successional species create more favorable ecological conditions for subsequent species, such as enhanced nutrient, water, or light availability. In contrast, inhibition happens when early successional species create unfavorable ecological conditions for potential successive species, such as limiting resource availability. In some cases, later successional species...
17.3K


