Tree Crown Structure and Leaf Surface Using Three Species of the Genus Ulmus L. as an Example
摘要
The leaf surface area is one of the main criteria of primary photosynthetic productivity of individual plants and plant communities. Characteristics of the leaf surface in the tree crown vary greatly. In a tree, as a long-existing perennial organism, the crown structure determines the location of the photosynthetic surface of the current and subsequent vegetation seasons. The surface area of leaf blades of biennial shoot systems of virginial and early generative trees of three species of the genus Ulmus L. was studied: U. glabra Huds., U. campestris L., U. parvifolia Jacq. A set of the most important structural features of the shoot that determine the properties of the leaf surface was identified. For three species of the genus, differing in morphological, ecological and phylogenetic qualities, a comparison of biennial shoot systems was carried out, characteristic species features of the leaf surface were revealed, as well as general properties of biennial shoot systems as spatio-temporal units of the tree crown structure.