Soil-to-Plant Transfer of Radiocaesium in Thailand

Abstract

Soil-to-plant transfer factors (TF) of radiocaesium-137 were estimated by considering soil properties of 51 provinces in Thailand, and by using the model of Absalom. According to our study, the Absalom model could estimate average TF values to be 0.0852 ± 0.0475. Compared with average
measured TF values which was 0.1289 ± 0.0529, it was found that calculated TF values decreased with increasing pH, clay contents and exchangeable K⁺. The corresponding calculated TF values increased with increasing organic matter contents and NH₄⁺ concentrations. Statistical analysis showed that Relative Euclidean Difference (RED) was 0.238, reliability index (k) was 0.661 and geometrically intuitive reliability index (k_g) was 1.97, which confirmed that the Absalom model was reasonably accurate. Calculated TF values by the Absalom model were in good agreement with the measured ones. However, calculated TF values were found to be significantly different from the measured ones for some provinces in Thailand. The parameters used in the Absalom model needed to be modified to suitably match soil properties in Thailand.