福島第一原子力発電所事故により放出された放射性セシウムの土壌中での動態と制御因子

抄録

Selective adsorption at the frayed edge site (FES) of micaceous minerals is the most important reactions controlling soil-to-plant transfer of radiocesium. In this article, radiocesium adsorption on soils and minerals are reviewed, especially focusing on the wide differences in the amount or effectiveness of the FES between soils. Micaceous mineral contents in parent materials primarily control the FES in soils. Whereas granitoids and shales typically contains biotite and illite, respectively, other rocks may have developed to FES-poor soils unless eolian dusts had been deposited from continental desert areas. Weathering of micaceous minerals into vermiculite increases the FES content. However, large portion of the FES could be inaccessible for radiocesium in soil environments, either through the mineral coverage with humic substances or hydroxy-Al polymers interlayering. Thus, soil formation processes are important to understand how soils obtained the ability to retain radiocesium.