| 11 sorts of plant samples and corresponding soil samples were collected in Conghua and Taishan, Pearl River Delta. The specific activity of 238U、 226Ra、 232Th and 40K of samples were investigated by using HPGe-γ-ray spectra analysis. The results showed that the average specific activity of 238U，226Ra, 232Th and 40K in soil samples were 151.8, 146.3, 226.6, 665.5 Bq/kg, which were higher than the average values of China and the world. The concentration of 238U in all sort of plants are very low and most of them are lower than detection limit, while the values of 226Ra, 232Th and 40K were high. The contents of 226Ra and 232Th in Dicranopteris dichotoma were the highest, whose average specific activity is 285.9, 986.2 Bq/kg respectively. The average bioconcentration factors (BFs)of 226Ra,232Th of Dicranopteris dichotoma were 2.20, 4.23, respectively, the other 10 sort of plants have BFs of 226Ra,232Th were in the range of 10-1-10-2. The bioconcentration factors and the translocation factors of 226Ra, 232Th of Dicranopteris dichotoma were all bigger than 1, so Dicranopteris dichotoma can be defined as hyperaccumulator of 226Ra and 232Th. defined as hyperaccumulator of 226Ra and 232Th. |
