The Role of Cryogenic and Cryopedogenic Processes of the Past in the Formation of Al–Fe-humus Soils in the Nadym–Pur Interfluve, North of Western Siberiaстатья
Статья опубликована в журнале из списка Web of Science и/или Scopus
Аннотация:Al–Fe-humus soils in the Nadym–Pur interfluve (Novyi Urengoi)—Albic Podzols and EnticPodzols—are considered. The soils are formed on the sedimentation matrix of Karginian alluvium transformedin the Sartan Period by low-temperature cryogenesis. The studied profiles are classified as iron-illuvialdeep podzolic tongued cryoturbated sandy podzols and iron-illuvial podburs. Cryoturbation of Albic Podzols isassociated with modern processes in the seasonally frozen layer. A specific feature of their evolution is their formationon well-drained sandy terraces with polygonal-blocky relief created prior to podzol formation during thedevelopment and melting of Sartanian polygonal wedge ice. This relief is now represented by gentle polygonswith sides of 8–12 m long separated by depressions along the axes of pseudomorphs (ice-wedge casts) along theformer polygonal ice wedges. The height difference between such areas reaches 1 m. Snow accumulates in thedepressions, the substrate in them becomes more moistened and permeable, and Albic Podzols form elongatedtongues, which are the longest within the illuvial horizon. The total mean thickness of the eluvial and illuvialhorizons is about 50 cm, but tongues penetrate into the pseudomorphs two to three times deeper. It is assumedthat this is not a factor of cryogenic transformation of podzols, but rather their feature inherited from previouslyformed cryogenic structures. Albic Podzols began to form on Sartan paleocryogenic relics and related cryohydromorphicpaleosols 7000–8000 years ago. The Al–Fe-humus soils partially erase the evolutionary history ofprevious pedogenesis, the relics of which can be embedded in them. The features acquired by modern soils dueto such incorporation may be taken as an indicator of a different type of soil formation.