Ecological and phytocoenotic features of the vegetation cover of the Beshpagir Heights (Stavropol Upland)

The authors have studied herbaceous communities in the steppe landscapes of the Beshpagir Heights and this paper presents the results of this study. The floristic and ecological structure of phytocoenoses on limestone outcrops of the parent rock is discussed. As a result of the research carried out in 2019–2020, 185 species of higher plants were identified in the modern flora of the studied steppes. There are descriptions of 16 accounting sites. A phytocoenotic table is presented, a characteristic of communities is given and their structure is described. The abundance of species and the distribution by relief elements and communities were determined by experts on the basis of field information. The features of communities and the reasons for their spatial differentiation are revealed. It has been suggested that the factors determining a diversity of steppe vegetation in the studied region should be the following ones: the degree of destruction of the parent rock and soil development, high insolation and low ecotope moisture. The steppe communities are distinguished by their species richness and are of significant conservation interest; they include such rare and endangered species as Psephellus annae, Stipa pulcherrima, S. pennata, Scabiosa isetensis, S. micrantha, Medicago cancellata, Astragalus bungeanus, A. pseudotataricus, A. calycinus, Iris pumila, I. notha, Erodium stevenii, Thymus daghestanicus, Gypsophila glomerata, Allium inaequale, etc. The authors have shown that the studied steppes are important for the preservation of the biological diversity of the region; habitats of rare species are of scientific importance. By this research the authors have tried to emphasize the regional specificity of the studied communities, due to the geographical, ecological-coenotic and historical features. The results obtained will make it possible to assess the real phytocoenotic diversity of the steppe complex of the region, as well as to update further work on the inventory and monographic generalization of vegetation materials of the Stavropol territory. The typology of steppe vegetation can be detailed in further work.