Ecological-cenotic structure of flora in the Argun river basin

Introduction. The article presents the features of the flora within the Argun River basin, which, as a mountainous area, is characterized by a fairly large landscape and phytocenotic diver sity, determined primarily by the altitude zone and variety of substrates, resulting in the presence of a significant number of ecological niches inhabited by floral complexes and floral elements with similar ecology. First of all, these are various types of vegetation–steppes, meadows and forests, which naturally change with changes in altitude above sea level, as well as multi-belt complexes of petrophytes, hydrophytes and ruderal species. The main phytoceno ecological niches are fragments of steppes, broad-leaved, small-leaved and coniferous forests, subalpine and alpine meadows, exposed parent rocks of different steep ness, exposure and consistency (rocks, moraines, scree, placers, etc.), various soils, river and lake coasts, agrocenoses and disturbed habitats, etc. Materials and methods. The material for the study was herbarium material collected durin gexped it ions conducted in the study are from 2020 to 2023 in various altitude zones of the Argun River basin. The object of the study was selected floras pecies and floral complexes with various habitats with in the Argun River basin. A.I. Galushko’s methods and statistical methods of analysis were used for data processing. Results. Key environmental characteristics have been studied. It has been established that the dominant flora cenoses belong to the meadow-petrophilic-weed category and include 1314 plant species (84.3% of the total composition). If only reliably defined serotypes are taken into account (there are 850 species or 54.6%), there is a predominance of meadow-petrophilic-forest types of florocenoses. Discussion. As are sult of the analysis, it was found that the active anthropogenic trans formation of the flora of the Argun River basin is reflected in an increase in the number of facultative species and a reduction in specialized species, which negatively affects the stability of natural communities. Conclusion. In total, the vascular vegetation of the basin includes 1.558 plants pecies from 569 genera belonging to123 families, united within 76 orders and distributed into nine classes of six divisions. The practical application of the results lies in the possibility of using them for further research in the field of conservation of the biodiversity of the Argun River basin and optimization of environmental management in this region.