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The results of the investigation into the history of soilscapes in the Kislovodsk Depression are dis cussed. It is shown that up to 60-70% of the area of slopes and interfluvial plateaus at the heights of 900-1500 m a.s.l. was terraced in the Late Bronze-Early Iron ages, during the Kobansk cultural stage (1200-600 BC). Under these conditions, a sharp change in the climate with a considerable increase in the annual precipitation in the middle of the first millennium BC resulted in the activation of erosion and the formation of a layer of colluvial sediments overlying the buried soil on the terraces. Thus, the middle of the first millen nium BC can be considered the zero moment for the modern stage of soil formation in the region. Problems of the current state of the terrace complexes and the development of erosion on them are also discussed.

Chernozems or mollisols/black soils are 'reference soils' with a high content of organic matter, which ensures a high level of crop yield. In the article, we describe the structural characteristics of a typical medium‐thick Chernozem taken from Kursk region and their improvement via treatment by a 1 wt% aqueous solution/suspension of interpolyelectrolyte complex (IPEC), a product of electrostatic interaction between anionic potassium humates and cationic poly(diallyldimethylammonium chloride). The native Chernozem and polymer‐treated chernozem were characterized by laser diffraction, dry and wet sieving methods, transmission electron microscopy, soil washoff in a hydraulic erosion tray, gravimetry, visual control, and vegetation miniaturization in Petri dishes with the following main conclusions: (a) Deposition of a positively charged IPEC over the Chernozem sample led to an increase in a total amount of agronomically valuable 0.25–1 mm aggregates up to 28% in comparison with a 3% content of aggregates in the native Chernozem. (b) An average diameter of the air‐dry aggregates, treated by a cationic IPEC, was of 5.5 mm (cf. with 2.5 mm for the untreated). (c) An average diameter of the IPEC‐treated water‐resistant aggregates was of 2.1 mm (cf. with 0.5 for the untreated). (d) The Chernozem pretreated by the cationic IPEC showed a minimum removal of soil during several cycles of rewatering/drying. (e) All IPEC formulations, stimulated the growth of plants. The results are of interest for preparing low‐toxic polymer formulations capable of effective stabilizing fertile Chernozem soils.

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