Home – Home – Jornals – Geography and Natural Resources 2020 number 2

For the first time, the description of soils evolving in the zone of influence of the discharge of thermal mineralized waters of hydrogen sulfide hydrocarbonate-sulfate-sodium type (Kuchiger source) is provided for the Baikal rift zone. Under the influence of the paleo-discharge and modern (active, hidden) discharge of hydrotherms across a large area of the forest-steppe zone in the northwestern part of the Barguzin depression, saline, highly saline and solonetzic soils of sulfate-sodium type of chemistry are formed. The morphological structure of saline soils differs significantly from zonal and intrazonal (floodplain) soils by the presence of turbation processes in them. The areas of active manifestation of the ascending gas-hydrothermal fluids show a high degree of turbation of soils, whereas a low degree of turbation is observed in areas of paleo-discharges. Turbation can be associated with the manifestation of tectonic folding processes in seismically active areas as well as can have a cryogenic origin. Along with sali nization processes, in remote locations, sites of paleo-discharge of a mineral source show the formation of humus-clay revestments, indicating the manifestation of the solonetz process. For the first time for soils of Transbaikalia, an accumulation of crystals of powdery gypsum in solonetz subtypes was observed. Soils of tectonic fault zones with outcropping thermal water are characterized by an extremely high dynamics of soil formation conditions, which is manifested in a contrasting combination of physicochemical properties of soil horizons and heterogeneous granulometric composition. The geochemical uniqueness of the saline soils under study is associated with anomalously high concentrations of S and high concentrations of Ba, Sr, P and Na. The endogenous factor has a considerable influence on the morphological structure and properties of soils, which allows us to identify turbated subtypes unusual for the background soils. According to the morphological structure and material composition of saline soils, they belong to the orders of alluvial soils of the synlithogenous trunk and halomorphic soils of the post-lithogenous trunk.