The paper presents the study of soil cover of the steppe areas on the territory of the Daursky State Nature Biosphere Reserve in Transbaikalia (East Siberia). We determined the types of soils in the area surrounding the currently dry Barun-Torey lake according to the modern classification: Chestnut typical and saline, Saline gleyed typical and sulfide (sor) typical. Typical chestnut soils are formed on the tops of lake terraces and form complexes with saline soils. Salted chestnut soils occupy transit landforms. Saline soils are confined to low relief forms of the shoreline and the bottom of the lake, where the accumulation of readily soluble salts occurs. Typical Chestnut and saline soils are characterized by a light granulometric composition and a low humus content. Sulphide and typical gleyed saline soils have a heavier granulometric composition, a highly alkaline reaction of the soil solution, a very low humus content and a high content of readily soluble salts. The natural factors of soil formation are: slightly dissected relief; arid and cryoarid climate; groundwater level; steppe and halophytic meadow vegetation. Chestnut soils that form at the tops of lake terraces are the most common. Solonchaks occupy low relief forms of the lake shoreline and lake bottom.

Khadeeva Ekaterina Romanovna, Leading Technologist, Institute of Geography SB RAS, 1, Ulan-Batorskaya st., Irkutsk, 664033, Russian Federation, e-mail: war_ker@mail.ru

Lopatovskaya Olga Gennadyevna, Doctor of Science (Biology), Associate Professor, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: lopatovs@gmail.com

Saraeva Lyudmila Ivanovna, Senior Research Scientist, Daursky State Nature Biosphere Reserve, 76, Komsomolskaya st., Nizhny Tsasuchey settl., Zabaykalsky Region, 674480, Russian Federation, Lead Engineer, Central Siberian Botanical Garden SB RAS, 101, Zolotodolinskaya st., Novosibirsk, 630116, Russian Federation, e-mail: bagul72@mail.ru

Tkachuk Tatyana Evgenyevna, Candidate of Sciences (Biology), Senior Research Scientist, Daursky State Nature Biosphere Reserve, 76, Komsomolskaya st., Nizhny Tsasuchey settl., Zabaykalsky Region, 674480, Russian Federation,Associate Professor, Transbaikal State University, 30, Alexandro-Zavodskaya st., Chita, 672039, Russian Federation, e-mail: tetkachuk@yandex.ru

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