Uptake of uranium, thorium, radium and potassium by four kinds of dominant plants grown in uranium mill tailing soils from the southern part of China

The concentrations of radionuclides in soil from uranium mill tailings in South China were analyzed. The results showed that all radionuclides in soil samples exceeded the soil background value. Through the field investigation, four kinds of dominant plants were identified. It was found that the total quantity of radionuclides in the whole plant from high to low were pokeberry, Cibotium barometz, reed and garden sorrel. We also found that Cibotium barometz had the highest transfer factor (TF) for U-238, garden sorrel had the highest TF for Th-232 and reed had the highest TF for Ra-226 and K-40. Cibotium barometz had the highest bioconcentration factor (BF) for U-238, Th-232 and Ra-226, and pokeberry had the highest BF for K-40. Pokeberry had the highest phytoremediation factor (PF) for U-238, Th-232, Ra-226 and K-40. On the basis of the above conclusions, pokeberry could be a candidate for phytoremediation of radionuclide-contaminated soils.