Evaluation of the variation of 226Ra and Ca uptake by plant and their relationship

AbstractThe transfer of 226Ra from soil to plant has been studied for wild trees and grasses to identify the site- and the plant-specific variability in relation to the transfer of Ca. Twelve species of plants and soils were sampled from three different forests and one flood plain in Okayama, Japan. The concentrations of 226Ra in plant varied about 60 times by species and sites, while those in soil were not different significantly among sites. The transfer factors defined as the concentration ratio of 226Ra between plant and soil were linearly correlated with that of Ca, implying that the ability of Ca uptake by plant reflect the ability of 226Ra uptake. The Ca concentrations in plant showed species-specific value and varied 22 times. The range of transfer factor (plant/soil) for Ca increased by the variability of the Ca concentration in soil among sites. These results suggest that the wide variability of 226Ra concentration in plant can be ascribed to both the differences in plant and soil factors of Ca ...