Abstract

This article presents the results of studies on the structural organization of the crown in Ulmus glabra. Knowledge of types of shoot systems regularly changing in the tree crown in the ontogenesis of a species is of both theoretical and practical importance. In our studies, we use an architectural (modular) approach that enables us to describe the spatiotemporal program of tree-crown development. The results show that the main structural unit of the tree crown, resistant to the changes in climatic factors, is a biennial shoot system (BSS). The choice of this unit is determined by the fact that zonality in maternal shoot can be detected only in the second year of the shoot lifespan. To identify the spatiotemporal structure of the BSS, we have compared the traits of 1- and 2-year-old shoots. The BSS of U. glabra undergrowth plants in the forest-steppe oak forest of the Belogorye Natural Reserve have been studied. The study involves 100 species of the same ontogenetic stage. The shoot systems in the studied trees have been differentiated into large (“growth”) and small (“basic”) ones with the same location within the crown. Based on the cross-correlation function, which depends on the internode number on the maternal shoot, a regression model of the length distribution of lateral shoots has been created. It is shown that, when numbering the internodes on the maternal shoot from the top downwards, the dependence of the lateral shoot length of both the growth and the basic BSS in U. glabra vs. the number of internodes is consistent with the exponential model. The development of the BSS is found to be dependent on the light conditions and positioning in the crown. The comparison of two samples allows us to introduce a shift parameter into the model, which defines a specific zone in the maternal shoot.

中文翻译：

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作为对Ulmus glabra Huds牙冠发育进行建模的单元，每两年拍摄系统的功能

摘要

本文介绍了榆树冠的结构组织研究的结果。在物种的个体发生过程中，树冠中经常变化的芽系统类型的知识在理论上和实践上都很重要。在我们的研究中，我们使用一种架构（模块化）方法，使我们能够描述树冠发育的时空程序。结果表明，抵抗气候因素变化的树冠的主要结构单位是两年一次的芽系统（BSS）。该单位的选择取决于以下事实：母芽中的区域性只能在芽寿命的第二年才能检测到。为了确定BSS的时空结构，我们比较了1岁和2岁幼芽的性状。的BSS研究了Belogorye自然保护区的森林草原橡树林中的U. glabra灌木丛植物。该研究涉及100个相同的个体发育阶段。被研究树木中的芽系统已被划分为大（“生长”）和小（“基本”）树，它们在树冠内的位置相同。基于互相关函数，该函数取决于母枝上的节间数，建立了侧枝长度分布的回归模型。结果表明，当从上到下对母芽上的节间进行编号时，其生长和基本BSS的侧芽长度都具有相关性。与节点间数量的关系与指数模型一致。发现BSS的发展取决于光照条件和表冠位置。两个样本的比较使我们可以将偏移参数引入模型，该参数定义了母本幼芽中的特定区域。