Inventory of the Biodiversity in the Northwestern Exclave of the Meadow Steppe (Based on the Results of 50-Year Monitoring)

Abstract

Significant climate shifts observed in recent decades may lead to changes in the composition and structure of natural communities. This article presents the results of the inventory of biodiversity in steppe stationary sites of the northwestern exclave of meadow steppes in the Prioksko-Terrasny Biosphere Reserve (Moscow Region) over 50 years of observations. Geobotanical studies were conducted both at stationary sites and by route methods. Continuous stationary monitoring covers the period of the relative climatic norm (1975–1985) and the global warming trend (1998–2022). Currently, the Checklist of steppe stationary plants includes 155 species (152 species are vascular plants, two are mosses, and one species is a lichen). Over the past 25 years (1998–2022), more than 20 new plant species have been recorded at steppe stationary sites. Among the newly recorded species, annuals and psammophytes predominate, represented by single finds. However, there is an increase in the number of some southern perennial species or an expansion of the area occupied by their populations, as well as flowering and fruiting of species that previously did not reach the generative phase of development. Three species of the Red Data Book of the Moscow Region have been recorded which were not previously listed in the steppe communities. The floristic core of the isolated steppe ecosystem consists of about 50 species represented by perennial steppe and meadow-steppe grasses. Stationary studies show that, in general, the meadow steppe ecosystem in the reserve exhibits a stable species composition. However, the recorded increase in the projective cover of xerophilous grasses allows us to state that in the last 20 years, xerophytization of the northwestern exclave of the meadow steppe has been on the rise.

Funding: the work was carried out within the framework of state assignment 122041200035-2.