Verification of a Migration–Dosimetric Model Describing the Formation of the Radiation Situation in Pine Stands in the First Year after Catastrophic Fallout

The verification is presented of computation units in a migration–dosimetric model designed to estimate the following: (1) the redistribution of radionuclides between compartments of the system “crown surface of woody plants–forest litter or moss cover–surface soil layer” after an inflow of emergency radioactive fallout into pine stands and (2) the external γ-radiation dose rates determined by this redistribution. It is established that computed values are consistent with the empirical data collected in the course of radioecological monitoring (1987–2008) in pine stands growing in the 30-km exclusion zone of the Chernobyl nuclear power plant. The computed 137 Cs activity values in the main compartments of the studied system are in good agreement with the field data collected in 1987. Differences between the measured and forecasted values of the absorbed γ-radiation dose rate at a height of 1 m above the ground cover surface do not exceed 10%; this indicates that the dosimetric unit of the model adequately describes the main quantitative characteristics of the ionizing radiation field in pine stands.