Comparative assessment of the distribution of 137Cs in the soil cover on the territory of Tajikistan

The article presents the results of a comparative assessment of the distribution of the technogenic radionuclide 137Cs in the soil cover on the territory of the Republic of Tajikistan. It is noted that the accumulation of the 137Cs isotope in the territory depends on the terrain and soil type. At the foot of the mountains and in clay soils, a relatively high content of the 137Cs isotope is observed compared to plains and sandy soils. The migration of radionuclide 137Cs deep into the vertical is observed in the soils of sandy rock. It is shown that the values of the average specific activity of the 137Cs isotope in the soil cover of Southern Tajikistan are 2.5 times lower than the average specific activities of the soils of Northern and Central Tajikistan. The highest values of specific soil activity of 17.0 Bq/kg were noted in the southeastern regions of Tajikistan. This circumstance is primarily due to the fact that precipitation and dust storms coming from the countries of South and Southeast Asia lead to the settling of particles, primarily on the slopes of the mountains. Thus, based on the analysis of the literature review in the direction under study and the results obtained, the authors revealed that the spatial distribution of 137Cs radionuclide in the soil cover in the Republic of Tajikistan depends on the direction of the wind rose and the terrain. Analysis of the samples obtained allows us to conclude that the content of 137Cs radionuclide is due to its long-range air transport.