Soils in loess-like loams within the seasonally frozen landscapes of the Selenga Middle Mountains (Western Transbaikal Region)

Loess-like loams in the Selenga Middle Mountains are formed within a layer of soils that experience prolonged seasonal freezing. The permafrost in this area is characterized by a low ice content. This study aims to explore the genetic characteristics of soils derived from loess-like loams under the long-term seasonal permafrost conditions prevalent in the Selenga Middle Mountains. The research focuses on Eutric Retisol and Eutric Cryosol, which are located in eluvial and transeluvial positions on the watersheds of the primary ridges in the region. A profile-genetic approach was employed, and the physical and chemical characteristics of the soils were evaluated using standardized methodologies. The total organic carbon (C_org) content was measured in accordance with the Tyurin method, while the analysis of oxalate-extractable iron was conducted utilizing the Tamm method. The particle-size distribution was assessed through the pipette method. Soil classification adhered to the standards set forth in the Classification and Diagnostics of Soils of Russia and the World Reference Base for Soil Resources. The genesis and characteristics of the soils under investigation are predominantly influenced by cryogenic processes. Eutric Retisol exhibits a differentiation consistent with eluvial-illuvial processes, while the podzolic horizons are characterized by a thin-plate structure with a skeletal surface on the peds. This research represents the first examination of Eutric Cryosol, which displays minimal differentiation in terms of color, structure, soil texture, and elemental composition. The practical implications of this study are significant for the sustainable management of soil resources within the permafrost zone of the Selenga Middle Mountains. The presence of charcoal particles within the soil profile suggests a history of frequent ground fires, highlighting the necessity for monitoring forest fires and implementing environmental protection measures to safeguard natural resources.

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