Mitigation of radium-226 in agricultural soils and influence of soil-to-plant transfer factor and physical–chemical properties of soil

The mitigation rate (R_j) was evaluated for Ra-226 in cultivated soil in twelve fields in Vietnam. For the collected soils, the R_j values were between 0.1 and 0.58 Bq kg⁻² y⁻¹ with an average value of 0.28 Bq kg⁻² y⁻¹. The influence of the physicochemical properties of soil and cultivation characteristics on the rate of Ra-226 was considered. A strong correlation was found between the soil-to-plant factors (TF) and the uptake rates of plants (R_u) (Pearson coefficient |p|> 0.6). The leaching rate (R_ℓ) in the surface soil correlates with some physical–chemical properties of soil such as the partition coefficient of Ra-226 in soil (K_d), infiltration rate of water (R_w), and activity concentration of Ra-226 in soil water (C_w) (|p|> 0.6).