Gamma radiation and radionuclide distribution in soils of rostov: implications for urban and natural environments

The gamma radiation equivalent dose rate and specific activity of Ra, Th, K and Cs in soils of different functional zones of Rostov agglomeration and associated specially protected natural areas were studied. The objects were Calcic chernozems and urban technosols of Rostov region. The gamma radiation equivalent dose rate was measured using search dosimeters-radiometers (SRP-88n, DRBP-03) by gamma-pass method. Progress-Gamma scintillation gamma spectrometer with a detector (NaI(Tl)) was used to determine the specific activity of radionuclides in soils. Assessment of the radiological situation showed that the average values of gamma background are 0.140 μSv/h for the residential zone, 0.123 μSv/h for the recreational zone and 0.130 μSv/h for specially protected areas. The data obtained for Rostov agglomeration correspond to the average values for soils of background territories typical for Rostov region. However, in some areas there is an increase in the gamma equivalent dose rate in the zone of high-rise and low-rise residential urban development relative to background and recreational areas. These results can be attributed to the utilization of materials with elevated radioactivity levels in urban construction. Median values of activity of natural radionuclides decrease in the following row—“soils of residential areas” > "soils of recreational areas" > "soils of specially protected natural areas". ¹³⁷Cs activity in soils of the residential and recreational zones of the city is at the same level, with single peaks of specific ¹³⁷Cs activity for individual specially protected natural areas, where the maximum coefficient of variation was also revealed.