Absorption of gamma-emitting fission products and activation products by rice under flooded and unflooded conditions from two tropical soils

Abstract

The absorption of gamma-emitting fission products ¹⁰⁶Ru,¹²⁵Sb,¹³⁷Cs and¹⁴⁴Ce and activation products⁵⁹Fe,⁵⁸Co.⁵⁴Mn and⁶⁵Zn by rice plants grown on two contrasting tropical soils, namely, a blak soil (pellustert) and a laterite (oxisol), and the effects of flooding were studied under controlled conditions. Results indicated greater uptake of ¹⁰⁶Ru and ¹²⁵Sb from the black soil than from the laterite. In contrast, the uptake of ¹⁴⁴Ce and ¹³⁷Cs was greater in the laterite than in the black soil. Flooding treatment enhanced the uptake of all these fission products by rice plants in the laterite soil whereas this effect was observed only for ¹²⁵Sb and ¹³⁷Cs in the black soil. The plant uptake of activation products from the two soil types showed maximum accumulation of ⁶⁵Zn followed by ⁵⁴Mn,⁵⁹Fe and ⁵⁸Co in both soil types. Besides, uptake of these nuclides was greater from the laterite soil than from the black soil. Flooding treatment for rice while showing a reduction of ⁵⁹Fe uptake, showed an increase in plant uptake of ⁵⁸Co,⁵⁴Mn and ⁶⁵Zn in both soil types.