Rosén, Klas
- Department of Soil and Environment, Swedish University of Agricultural Sciences
A loamy soil contaminated with (CsCl)-Cs-137 40 years ago was investigated by a sequential extraction technique to determine the effect of ageing on chemical availability of (CS)-C-137. The soil samples were sequentially extracted with H2O, NH4Ac, NH2OH center dot HCl, H2O2, and HNO3. Extractability of 137 Cs decreased in the order: HNO3 > Residual > H2O2 > NH4Ac > NH2OH center dot HCl > H2O. Only 0.94% in labile fractions (H2O and NH4Ac), while more than 96% was found in the strongly bound fraction (HNO3 and residual). However, the activity percentage in labile fractions was increased to 1.34% after autoclaving treatment, while those in the other fractions did not significantly differ. This indicates that the microbial activity played a role in the Cs-137 retention. In the subsequent pot experiments with ryegrass and leek, specific activities in both plants were significantly higher in autoclaved soil than in non-autoclaved soil, and uptake of (CS)-C-137 in the five cuts by ryegrass was 25% of the labile (CS)-C-137 in the soil. In addition, a positive correlation was found between the amount of (CS)-C-137 in labile fractions and that by plant uptake.
ageing; leek; microbial activity; radiocesium; ryegrass; sequential extraction
Environmental Monitoring and Assessment
2007, volume: 129, number: 45660, pages: 309-314
Agricultural Science
https://res.slu.se/id/publ/23061