In this study we investigated artificial (¹³⁷Cs, ⁹⁰Sr) and natural (⁴⁰K) radioisotopes’ vertical distribution in different usage soils. Soil samples were collected in Lithuanian territory, which was, after the nuclear weapons and the Chernobyl Nuclear Power Plant (ChNPP) accident, contaminated with artificial radionuclides. For the study, three places were selected, taking into account human activities and radioactive environmental contamination (Neris Regional Park, a field near the Ignalina nuclear power plant and a field in a village in Ukmergė district). In addition, we analysed the soil organic matter, which determines the amount of nutrients, water infiltration, ion exchange, adsorption of pollutants. Studies show that in those places the predominant soil type is sandy loam, with soil mineralization rate close to 1. In the village place and the regional park place (respectively Jogvilai and Paaliosė areas), ¹³⁷Cs specific activity decreases exponentially. However in the village place (Paaliosė), at 10-15 cm soil depth, there is a noticeable increase in the specific activity of ¹³⁷Cs, associated with the former nuclear weapons test contamination. ⁴⁰K changes the specific activity of the soil samples taken from the depth in all areas. In the village place (Paaliosė), and the field near the Ignalina nuclear power plant (Stabatiškės), ⁴⁰K specific activity decrease with the increase of depth was observed, and in the field in the village in Ukmergė district (Jogvilai) it was vice versa – with the increase of depth, ⁴⁰K specific activity increases. The average ⁹⁰Sr radionuclides in the soil are 6,4±1,1 Bq/kg (in the village place (Paaliosė)) 6,4±2,0 Bq/kg (field near Ignalina nuclear power plant) and 11,3±1,7 Bq / kg (the field in the village in Ukmergė district).

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