Acorrelation between the transfer factor of radioactive cesium from soil into rice plants and the grain size distribution of paddy soil in Fukushima

Abstract

 The transfer factors (TFs) from paddy soil to rice plants of radioactive cesium (¹³⁷Cs and ¹³⁴Cs) derived from Fukushima Daiichi Nuclear Power Plant (FDNPP) accidents in March, 2011 and grain size distributions were estimated in four paddy fields, A through D, in Fukushima City. Soil and rice samples were obtained in September, 2014. The soil was measured for ¹³⁷Cs and ¹³⁴Cs radioactivity by Ge semiconductor detector and separated by the dry sieving classification. The radioactivity of radioactive cesium in the soil was comparatively higher in fields C and D (> 4000 Bq/kg), but the TF in field B was the highest (1.9E-03) among the four fields. Meanwhile, the soil in fields A and B contained a relatively large amount of larger grains, such as medium sand. Grain size distribution might be related to the TF. This study shows a new correlation between the grain size distribution and TF.