Abstract
With the help of gradient analysis and Ellenberg eco-scales, factors of differentiation of vegetation cover (moisture, illumination, soil acidity, and soil richness in mineral nitrogen) were revealed. Using nonmetric scaling, an ordination diagram of the distribution of geobotanical descriptions was created for 50 years of research (from 1971 to 2021). Correlation of ordination axes and ecological factors was carried out. On the ordination diagram and according to the results of cluster analysis, geobotanical descriptions form three distinct groups corresponding to certain time periods. Changes in the species composition in plant communities are caused by changes in illumination, moisture, and trophicity. Under the influence of drainage and successions of the vegetation cover for 50 years, on the site of a mesotrophic hummock-flark herb sphagnum mire, represented by mesotrophic hydrohygrophilous mire species, an oligotrophic hummock lawn dwarf-sphagnum pine forest was formed, formed by oligotrophic, mesohygrophilic forest-mie species.