Preservation of the biodazonity of pasture agrocenoses of the dry steppes of the Lower Volga region

Nowadays, more than 85% of pastures are depleted, they have low productivity and poor biodiversity. Therefore, the priority is the issue of stabilizing the productivity of pasture agrocenoses, increasing their longevity and species diversity. The purpose of the research is to develop effective methods for stabilizing and increasing the productivity of agrocenoses in natural conditions and on artificially created lysimeters of the hydrological complex of the Federal Scientific Center of Agroecologyof the Russian Academyof Sciences. Reducing the load of small and large cattle on the pasture leads to the stabilization of the process of restoration of the vegetation cover of natural agrocenoses, but it is necessary to study all the mechanisms of soil degradation and develop a balanced and adapted range of pasture ecosystems. As a result of the research, a promising composition of polycomponent agrocenoses was selected, which is represented by herbs of the Stavropol selection, most of them are represented by the Poaceae family, in combination with Kochia prostrata (L.) Schrad., Artemisia arenaria D.C., and Eurotia ceratoides L. on lysimeters with a chernozem soil substrate, there are the best conditions for the growth and development of agrocenoses. The average productivity of green mass in terms of hay was 2.5 t/ha during the growing season. Over 70% of the phytomass is formed by grasses. On the light-chestnut sandy loam substrate on the pastures “spring - summer” and “summer - autumn” the lowest productivity of phytomass was noted - 2.2 t/ha. The results obtained will be used in the further study of the dynamics of soil degradation and the development of effective phytomeliorative measures leading to the conservation of the biodiversity of pasture agocenoses and their restoration in a changing climate.