TRANSVOLGA-TRANSURAL STEPPES OF THE NORTHERN SUBZONE OF THE STEPPE ZONE: SPECIFIC FEATURES OF THE MODERN FORMATION DIVERSITY
Safronova I.N., Kalmykova O. G., Stepanova N. Yu. TRANSVOLGA-TRANSURAL STEPPES OF THE NORTHERN SUBZONE OF THE STEPPE ZONE: SPECIFIC FEATURES OF THE MODERN FORMATION DIVERSITY // Arid ecosystems. 2020. V. 26. № 4 (85). P. 4-9. | PDF
The significant part of the native Transvolga-Transural steppes of the northern subzone of the Steppe zone is destroyed by plowing. And on large territory they are represented by fallow lands of different age. It is known that communities of many formations are spread throughout the steppe zone. The differences in the structure of undisturbed communities in different subzones are quite clear. On fallow lands and pastures these differences are poorly visible. Basing on many years of our research of the vegetation cover in the steppe zone we aimed in 2018–2019 to find out how much the diversity of formations on the fallow lands changes and how their structure can be used to appreciate the subzonal status of the territory. The research is based on field studies including a route method, more than 100 geobotanical descriptions made by standard method, the analysis of which uses ecological-phytocoenotic classification; more than 700 herbarium sheets were collected. We revealed that zonal Stipa zallesskii steppes do not currently dominate in the Transvolga-Transural part of the Northern subzone, but Stipa capillata steppes are dominant representing the background vegetation on the fallow lands. Along with Stipa capillata steppes large areas are occupied by secondary Stipa lessingiana steppes. As peculiar component of the vegetation cover of the Northern subzone we can mention the communities of dwarf semishrubs. They are confined to saline soils or to the outputs of the rocks. Halophytic and petrophytic variants of steppes are represented not only by semi-shrub communities, but also by perennial grasses.
Keywords: Transvolga, Pre-Ural, Transural, steppe zone, forb-feather-grass steppes, diversity.