СТАТИСТИЧЕСКОЕ ПРОГНОЗИРОВАНИЕ НАКОПЛЕНИЯ 137Cs В ПРОДУКЦИИ РАСТЕНИЕВОДСТВА НА РАДИОАКТИВНО ЗАГРЯЗНЕННЫХ ТЕРРИТОРИЯХ

Abstract

Purpose: the development of statistical models for forecasting the accumulation of 137Cs in crop production, model parameterisation and prognostic estimates for the territories of the Bryansk region contaminated with 137Cs because of the Chernobyl accident. Material and methods: The use of a probabilistic approach for correct predictive assessments of the safety of agricultural products from radioactively contaminated agricultural lands has been substantiated. Analytical models were developed in the framework of a probabilistic approach to predict the risks of radioactive contamination of crop products, to assess the permissible levels of contamination of arable lands and the time of their natural remediation. Results: Based on a statistical analysis of radioecological survey data, it was established that the 137Cs contamination density of the soil follows a lognormal distribution law with a high level of significance. For farms in the south-western districts of the Bryansk region, it was shown that, if the average values of 137Cs content in crop production corresponded to the established standard, the risks of its excess could reach 30 %. This is due to the variability of 137Cs soil contamination densities and migration parameters. The dependences of limiting soil contamination densities of 137Cs on the risk of exceeding the standards (RES) of the content of this radionuclide in products were presented. The time of natural rehabilitation of arable agricultural land with a given risk for products of 10 % can exceed 30 years. Conclusion: The application of probabilistic methods to predict the consequences of 137Cs contamination of agricultural lands makes it possible to correct practical recommendations developed on the basis of a deterministic approach. The results of prognostic calculations are the basis for planning and evaluating the possibility of returning territories contaminated by 137Cs to economic use. The developed methodology and models can be used in the development of decision support systems for the remediation of agricultural lands exposed to radioactive fallout.