THE ACCUMULATION OF TRACE ELEMENTS IN THE ABOVEGROUND MASS OF PLANT LIFE FORMS IN THE GEOSYSTEMS OF THE ONON-ARGUN STEPPE

The paper presents the results of analysis performed to reveal chemical features of the life forms of the aboveground mass of plant species predominating in the geosystems of the Onon-Argun steppe on the Kharanor transect testing area. On the basis of biogeochemical studies of plants, the possibility of analyzing the patterns of the geosystems’ functioning has been revealed. The choice of the Kharanor transect testing area was determined by the features of the landscape structure, forming a landscape-ecological series where facies are connected with each other. Facies of the Onon-Argun steppe as a whole are characterized by the low-mountain relief and a sharply continental climate change. To assess the climate of the study area, atmospheric precipitation and air temperature were analyzed (data from the Borzya weather station). Trace elements in plant ash were studied at the licensed chemical-analytical center of the V.B. Sochava Institute of Geography SB RAS. Each facies is characterized by a well-defined content of chemical elements in the green part of the aboveground mass as well as in the organs of individual plant life forms. The dynamics of accumulation and distribution of trace elements in the dominant plant species is traced. Their content changes significantly during the growing season. In the spring, during the active growth of plants, the content of trace elements increases, and their maximum falls on the tillering and maturation phases. The accumulation of chemical elements weakens in the earing and flowering phase and increases again by the end of the growing season.