Retrospective Assessment of the Formation of the Radiation Situation in Pine Plantations in the First Year after the Chernobyl Accident

The results of retrospective assessment of the density of radionuclide deposition as result of the Chernobyl accident for pine plantations growing on a northern highway of the Belarusian sector of the 30-kilometer zone around the station are presented. A decrease in the total density of soil contamination and the proportion of radionuclides of the fuel component of emissions was found with growing distance from the Chernobyl NPP. A change in the contribution to the absorbed dose rate from external β- and γ-radiation along the height of woody plants depending on the time and location of experimental objects in relation to the Chernobyl NPP is analyzed. The important role of external β-radiation in the formation of irradiation of crowns of woody plants in first months after radioactive fallout is shown. The decrease in the absorbed dose rate from external β- and γ-radiation in the studied plantings is proportional to the contribution of short-lived radionuclides to the total radioactive contamination. Up to 40% of the radiation dose absorbed by crowns of woody plants was accumulated in the first month after radioactive emissions, and up to 60% was accumulated during the next two months. The results of a retrospective assessment of the formation of the radiation situation in the first year after emergency fallout in pine plantings can be used to assess the long-term consequences of irradiation for living organisms.