Immobilisation of radiocesium in stemwood and the effect of the removal treatment of organic horizon

Abstract

In order to know the immobilisation of radioactive cesium to the tree of satoyama, we investigated the radioactive cesium in soil and stemwood. ¹³⁷Cs radioactivity of stemwood of Q. serrata was higher than P. densiflora. It shows that Q. serrata well abosorbed radiocesium. Though ¹³⁷Cs is located in the sapwood of Q. serrata, its concentration was quite different due to the direction of the trunk. It was estimated that the immobilization of ¹³⁷Cs in the stemwood of the treated stand was lower than control. Removal treatment of organic horizon of soil should affect the decrease of radiocesium in stemwood.