Radioactivity reduction experiment and the subsequent erosion in broadleaf hill forest after Fukushima ⅠNPP accident

• Published in: Journal of the Japanese Society of Revegetation Technology Vol. 40; no. 1; pp. 130 - 135
• Main Authors: YAMAMOTO, Rie, KOBAYASHI, Tatsuaki, EBATA, Chisa, SHINOZAKI, Keita, KOJIMA, Daichi, OTA, Shoko, MIYAMOTO, Ururuma, TAKAHASHI, Terumasa, SUZUKI, Hiroyuki, SEKIZAKI, Masuo, HOSHIZAWA, Yasuhiro, KOTAKEMORI, Toshihiko, YASUTAKA, Tetsuo, TSUJI, Hideki
• Format: Journal Article
• Language: English
• Published: Tokyo JAPANESE SOCIETY OF REVEGETATION TECHNOLOGY 2014; Japan Science and Technology Agency
• Subjects: air radiation dose; Fukushima Daiichi NPP accident; O horizon; radioactive cesium; soil erosion; surface runoff
• ISSN: 0916-7439; 0916-7439
• DOI: 10.7211/jjsrt.40.130

O horizon removal experiment was performed in broadleaf hill forest which had been extremely contaminated after Fukushima Daiichi Nuclear Power Plant accident. Soil 137Cs decreased to 13.7 % and air radiation decreased to 47.7 % in L-F-H horizon removed plot while air radiation dose decreased to 73∼76 % in L-F horizon removed plot. After the removal treatment, 9.65 % of 137Cs in forest floor had been washed away in L-F-H horizon removed plot during about 5 month. It was 0.64∼0.69 % in L-F horizon removed plot and 0.08 % in control plot. More than 96 % of these flown 137Cs erosion was trapped with fence at the bottom edge of plots. Concentration of dissolved 137Cs which is taken into plants easily was 9.5 Bq/L in control plot, 3.6∼6.5 Bq/L in L-F horizon removed plot and 2.1 Bq/L in whole L-F-H horizon removed plot.