Гидротермические особенности биотопов степной и лесной растительности Приокско-Террасного заповедника

Abstract

The growth of steppe plant species (so called “Oka flora” in the Prioksko-Terrasny Reserve) in the forest zone is a botanical phenomenon. To understand the mechanisms of such biogeographic anomalies’ formation, comparative studies of steppe communities’ habitats and zonal forest vegetation are important. In the article, for the first time on the original experimental material, an assessment of the humidity and hydrothermal regime of steppe communities’ habitat, its difference from biotopes of neighboring meadow and forest ecosystems, within the alien zone has been carried out. It is shown that the biotope of steppe vegetation has distinct differences from biotopes of other vegetation types of the reserve. The humid regime of meadow-steppe associations and the neighboring pine forest during the growing season is determined only by atmospheric precipitation, in contrast to the biotopes of other types of vegetation, in which the influence of upper water is noticeable. The most significant influence of the upper water was observed on the middle terraces of the Oka River (Rodnikovaya Polyana). Steppe vegetation of the Doly tract is formed in conditions of a “temperature trap” and lack of moisture during critical periods of spring and early autumn. The increase in summer temperatures and the duration of the summer period in the Moscow oblast’s southern part, as well as repeated droughts in the second half of summer and early autumn contribute to the preservation and expansion of the steppe area in the south of Moscow oblast.