Home – Home – Jornals – Contemporary Problems of Ecology 2021 number 5

The paper presents an overview of ontogeny of 11 life forms on the example of 16 species of boreal willows belonging to two ecological groups - alluvial and non-alluvial. At the intraspecific level, among the studied species, the greatest variety of life forms was found in alluvial species, and the smallest in non-alluvial species. In the species studied, polyvariety of evolution was revealed: structural and dynamic. As part of the structural polyvariety, morphological (as a result of which two or more (up to 4) life forms are formed in the adult state), dimensional (expressed in changing the size and life state of an individual within one ontogenetic state) are distinguished. Dynamic polyvariety is associated with different duration of pre-generative and generative periods of ontogeny. In all alluvial and most non-alluvial species, the predominance of the generative period of ontogeny over the generative one is observed. In individuals of two life forms of non-alluvial species, the pre-generative period prevails during ontogeny. Alluvial species have mastered a narrower range of environmental conditions compared to non-alluvial ones. At the intraspecific level, among the studied species, the greatest variety of life forms was found in alluvial species (2-4 life forms in each species), and the smallest in non-alluvial species (1-3 life forms in each species). Alluvial species are characterized by the presence of a small number of long shoots, a large number of shoots of medium length and a smaller number of short ones, which determines their high height compared to non-alluvial ones.