238U, 232Th and 226Ra behaviour in soils of mountainous tundra

Investigation into mountain-tundra soils of the Polar Urals for study of distribution and behaviour of natural radionuclides in them as well as search for correlations between radionuclides and physico-chemical properties of soils is conducted. It is shown that behaviour of 238U, 232Th, 226Ra in soils of mountain tundra obeys general regularities of soil-formation process in any type of soils. Content of radionuclides is determined by their concentration in soil-formation rock and by the effect of talus ablations but not by the type of soils. Radionuclides in turf stained-humic soils are associated with mineral-fragmental fraction of soils, in peat-gley ones. The main part of them has sorption origin, both ways of nuclide supply are observed in turf-gley soils