Features of the modern distribution of 137Cs in soils under overmoistened growth conditions of black alder forests in Zhytomyr Polissia, Ukraine

Research on the modern distribution of 137Cs in soils of different forest site types in black alder (Alnus glutinosa (L.) Gaerth.) stands was conducted. In forest litter, there is not a high percentage of its total activity in soil: in moist fairly fertile site type (C3) – 13.4 %, damp fairly fertile site type (C4) – 16.3 %, and wet fairly fertile site type (C5) – 3.8 %. The mineral part of the soil in moist and damp fairly fertile site type is characterized by decreased density of radioactive contamination of soil layers with depth. In wet fairly fertile site type, this indicator increases to a depth of 6 - 8 cm and decreases with further deepening. A 10-cm layer of moist fairly fertile site type (C3) contains 61.8 % of the total radionuclide activity in soil, damp fairly fertile site type (C4) – 68.1%, and wet fairly fertile site type (C5) – 70.1 %, correspondingly; a 20-cm layer has 75.4, 78.3, 91.9 % and a 30-cm layer – 80.9, 82.2, 96.0 % of the total radionuclide activity.