Quantifying the impact of forest management intensity and neighborhood diversity on individual tree shape and canopy space filling

造林干预的强度和所栽培树种的特性是森林管理的两个基本工具。它们可用于在特定环境条件和现行管理目标下控制林分的生态和经济价值。造林措施通过影响树冠和树干的尺寸和形状，决定了不同类群物种的生境质量和数量。过去，对森林的三维空间结构进行评估是非常困难的。这是由于研究对象的一般不可接近性、大小和复杂性，特别是如果还要考虑冠层。因此，我们对由于造林管理强度或不同邻域多样性而导致的树形结构明显变化的认识仍然很少，特别是当我们关注单个树的属性时，例如分支模式或树冠变形。因此，建议的项目将利用陆地激光扫描获得的树的独特空间信息来确定森林经营强度和树木邻居多样性对树冠形状、分枝格局和冠层空间填充的影响。每棵树形成一个林分的三维拼图将被详细地评估，并考虑到叶子上和叶子脱落的情况。我们将重点关注导致树木（树冠和茎）变形的过程，以及由此产生的空间占用模式，特别是在林冠上。利用激光扫描数据可以量化邻近树木的竞争以及不同树种对单个树木竞争强度的影响。此外，我们将能够使用一种新颖的方法来获得关于空间占用模式的定量信息，该方法基于代表不同大小的空间单元的立方体，在高细节（厘米）水平上评估3D数据。我们还将测试生态位分配理论是否可以证实，该理论预测物种丰富的温带森林比物种贫乏的林分具有更高的冠层空间填充。

The intensity of silvicultural interventions and the identity of the tree species that are cultivated are two basic tools of forest management. They can be used in order to control the ecological and economical value of a forest stand under given environmental conditions and the prevailing management objectives. By affecting the dimension and shape of tree crowns and stems, silvicultural measures determine habitat quality and quantity for species of various taxa. In the past it was very difficult to assess the three-dimensional spatial structure of a forest. This was due to the general inaccessibility, size and complexity of the study object, especially if the canopy layer is also to be considered. As a result, our knowledge on the distinct changes in tree architecture due to silvicultural management intensity or different neighborhood diversities is still small, especially if the focus is on single tree attributes, e.g. branching pattern or crown deformations. Thus, the suggested project will use unique spatial information on tree dimensions obtained from terrestrial laser scanning to determine the effect of forest management intensity and tree neighborhood diversity on crown shape, ramification pattern and canopy space filling. The 3D puzzle of individual trees forming a stand will be assessed in detail and for both leaf-on and leaf-off conditions. We will focus on the processes that lead to deformation of trees (crowns and stems) as well as the resulting pattern of space occupation, especially in the canopy of the stands. Competition by neighboring trees and the effects of different trees species on the competition strength enforced on a tree individual can be quantified using the laser scanning data. Furthermore, we will be able to derive quantitative information on space occupation pattern using a novel approach that evaluates the 3D data on a high level of detail (cm) based on cubes that represent spatial units of varying size. We will also test whether or not niche-partitioning theory which predicts higher canopy space filling of species-rich temperate forests compared to species-poor stands can be confirmed.