Micromorphological structure of permafrost- affected and seasonally long-term freezing loamy soils of the European Northeast

Micromorphological structure of tundra and forest-tundra soils occurred in pulverescent induviate loamy soils in the European Northeast is considered. The studied soils make bioclimatic genetic series: Iron-Cryogenic Gleyzems - Cryometamorphic Gleyzems - Iron-Illuvial Svetlozems. Cryogenesis plays leading role in their formation. Characteristic feature of these loamy soils is the presence of the middle non-gleyic cryometamorphic horizon CRM. The most important feature of the horizon is the specific angular, ooid (granular crumbly), curdy in the moist state, cryogenic structure. Typical of CRM micromorphology for both tundra and extreme north taiga soils is annular isolation of coarse disperse material around microaggregates, accumulation of sand-silty grains in most material, in pores and cracks.