Abstract: STUDIES ON THE SORPTION OF RARE EARTH Tb IN CALCAREOUS SOIL USING RADIOTRACESR~(160)TbChang Zheng;Du Jinzhou;Yue Sujun;Wei Hua;Tao Zuyi(Department of Modern Physics,Lanzhou University,Lanzhou 730000)Fan Zhongxiu(Lanzhou Agriculture School of Gansu Province,Lanzhou 730020)Abstract:The sorption isotherms of rare earth Tb in calcareous soil at various CaCl_2 concentration and temperatures are determined with radiotracer ~160Tb using batch equilibrium method.The soil sample is collected from the cultivated surface layer(0-20 cm deep)in Yuzhong county(in Gansu province).These isotherms can be described by the Freundlich sorption equation.It is found that the concentration of Tb~(3+)sorbed in calcareous soil increases with increasing temperatrue and decreasing concentration of CaCl_2.Keywords:Terbium,Calcareous soil,Sorption,Rare earth,~(160)Tb