Buried paleosols in balks of Kalmykiya as a record of late Holocene nature and society interaction

Modern and buried soils under valley sediments have been compared on the Southern Russian Plain (Kalmykiya) in the arid zone. The buried soil contains more humus and less carbonates, and pH values are lower. The humus content in this soil is comparable with that of modern Haplic Kastanozems and Gleyic Phaeozems. The comparison of differences in properties of buried soil at specific times and historical data on cultures’ functioning in these periods has allowed us to reveal the interrelation of nature and society processes development in South Kalmykia since the middle Holocene. Three stages of landscape development are recognized: (1) stable stage, at least 3000 years long (from the 2nd millennium BC until the 1st millennium AD), characterized by the formation of meadow-steppe soils; (2) dynamic stage, likely short, when deposits were accumulated, and soils were buried; and (3) modern stable stage, at least 500 years long (up to the present time), characterized by the formation of meadow-saline soils (Molli-Endogleyic Solonetz) on deposits in valleys. A strong ecological crisis was evident in the territory of modern Kalmykia about 1000 years ago, resulting from the collapse of the Khazar state. As a result, meadow-steppe soils were buried, and Saline Molli-Endogleyic soils were formed.