Tundra permafrost-affected soils study in the system «Active layer - permafrost» (north-east of European Russia)

Tundra mineral and organogenic permafrost-affected soils examined as the system "active layer - permafrost." The morphological and physico-chemical properties, the upper horizons of the permafrost are characterized by a gradual change in the "active layer - permafrost." Signs of the classical transition layer in permafrost-affected soils of the region appear insufficient, therefore proposed to use more generic term "upper layer of permafrost."