Initiatives by the Soil Fertilization Team to Develop Agricultural Technologies for Paddy Fields with Radioactive Contamination

Abstract

In April 2012, the paddy fi eld located 20.8 km from the Fukushima Daiichi Nuclear Power Station was divided into six plots to apply zeolite and potassium chloride, and a cultivation test of rice was carried out. The concentration of radiocesium in the brown rice was highest in the control plot at 17 Bq/kg, but in plots where zeolite and potassium fertilizer were applied, the concentrations had decreased to 5-6 Bq/kg. The effi cacy of zeolite effi cacy in inhibiting the absorption of radiocesium by rice plants is considered to be mainly the result of its ability to adsorb ammonium and potassium ions, thereby inhibiting the leaching and outfl ow of nitrogen and potassium from the plow layer. Radioactive Concentration of Paddy Field on Which a Test Planting of Rice Was Carried OutWe measured radioactive concentration in plow layer samples (at 15 cm) taken from a paddy fi eld located in the city of Minamisoma, 20.8 km from the Fukushima Daiichi Nuclear Power Station, and the total radiocesium concentration was