Cryogenic processes in soils of chalky landscapes in steppe zone south of the Orenburg region

Abstract

Abstract Specific microrelief marked by white chalky spots at the soil surface was studied in Volga-Ural region. The microrelief was described and soil features were studied in a soil trench across the microrelief including morphology and further micromorphology in the thin sections with the aim to better understand the genesis and functioning of chalky polygons, and to testify the hypothesis of their cryogenic origin. Wide range of cryogenic features was found both at macro- and microscale. Some are expected to be relict, while the other features are supported or formed by modern cryogenic processes. The further investigation of the temperature regime is planned to investigate the spatial diversity and role of winter freezing in the modern squeezing of wet powdery chalky material to the soil surface.