Iodine sorption and its chemical form in the soil-soil solution system in Japanese agricultural fields

Iodide (I-) or iodate (IO3-) sorption in two types of Japanese agricultural soil samples was investigated in consideration of microbial effects. A batch sorption test was carried out to observe sorption kinetics under four different experimental conditions characterized by temperature or microbial activity. The sorption kinetics results indicated that microbial activity promoted an increase of the soil-soil solution distribution coefficient. In addition, it was observed that the sorption kinetics of IO3- was similar to that of I-; for one sample. The results could be attributed to the fact that IO3- was transformed to I- in the soil solution. Therefore, in order to discuss the difference in sorption kinetics between I- and IO3-, it is important to check chemical forms of I in soil solution when IO3- is added to the sample.19th World Congress of Soil Scienc