Estimation of ¹³⁷Cs plant root uptake using naturally existing ¹³³Cs

In order to estimate soil-to-plant transfer factors (TFs) of ¹³⁷Cs using naturally existing ¹³³Cs, ¹³⁷Cs concentrations and some soil properties were measured in various crops and associated soils collected throughout Japan. Plants absorb elements in a plant-available fraction; because ¹¹³Cs is likely to behave similarly to K, exchangeable ¹³³Cs (ex. ¹³³Cs), which is thought to be plant-available, was estimated using the exchangeable K (ex.K) amount. For brown rice, a high correlation was observed between TF of ¹³⁷Cs and the ratio of concentrations of ¹³³Cs in rice to ex.¹³³Cs. Thus, TF of ¹³⁷Cs was estimated using four concentrations, i.e. ¹³³Cs in soil, ¹³³Cs in rice, K in soil, and ex.K. (author)