Soils of lake depressions in the steppe biome of West Siberia as indicators of Holocene climate rhythms

Buried Holocene soils and polygenetic pedolithocomplexes (PLCs) are found in the dried-off parts of the non-outflow lake depressions of the West Siberian steppe biome. Our research endeavored to assess the potential use of lake depression soil sand PLC as archives recording рaleoclimatic and paleoenvironmental conditions. Sargul Lake in the period of 7.5-5.8 ka cal yr BP experienced a regression stage of water accumulation. In the period about 5.8-4 ka cal yr BP the climate humidization led to the lake transgression, followed by a prolonged and steady regression stage up to 1.0 ka cal yr BP. Then a short-term transgression was recorded in 1.0-0.6 ka cal yr BP. In the Kuchuk Lake depression, a long sub-arid warm period in the middle and late Holocene (6.0-1.5 ka cal yr BP) was followed by climate humidization and relative cooling (1.5-0.9 ka cal yr BP), which at the end of Holocene (0.9-0 ka cal yr BP) was sharply replaced by climate aridization and warming. Around the same period (1.9-0 ka cal yr BP), the Bolshoi Bagan Lake depression also underwent through the lake regression.