Efforts towards Safety to Agricultural products
and Irrigation Water in the Disaster Area of Fukushima, Japan
Moono Shin1, Tomijiro Kubota2, Susumu Miyazu3 and Sangyoon Lee4
Abstract
Various decontamination measures, such as topsoil removal, the use of inverting plows, and decontamination using soil puddling with water, were implemented in the paddy fields and irrigation and drainage canals after the Tokyo Electric Power Company’s Fukushima Daiichi Nuclear Power Plant in 2011. The decontamination work of the government’s planned agricultural land (31,060 ha) was completed as of March 2018. Before agricultural activities can safely resume after this accident, it is necessary to evaluate the dynamics of radiocesium in irrigation water in the area. We measured the concentrations of radiocesium in irrigation water and analyzed radiocesium concentrations in rice and soil samples, the soil to brown rice transfer factor (TF) in two decontaminated paddy fields located within the zone where paddy rice culture was prohibited, and radiocesium/water balance in a paddy field in Fukushima prefecture after the accident. In this report, we introduce the efforts towards safety to agricultural products and irrigation water in the disaster area of Fukushima prefecture, Japan. Our key findings were as follows: (1) the soil to brown rice TF was 0.0015–0.0068 in the decontaminated paddy fields where soil improvement was performed to increase the content of exchangeable potassium to 200 (mg K)/kg soil before the conventional application and (2) the concentration of radiocesium in brown rice was About one tenth or less of the standard limit in Japan (100 Bq/kg), and the impact on brown rice from radiocesium in the irrigation water was limited.
Keywords: Paddy field, Irrigation water, Radiocesium, Fukushima, Decontamination
Acknowledgements: This study was supported partly by a grant-in-aid from the Kurita Water and Environment Foundation (15A012 and 16K004) and JSPS KAKENHI Project (16H01791). We gratefully acknowledge the help of many people during our research.
Reference
Ministry of the Environment, Government of Japan (MOE) (2019) Environmental Remediation in Affected Areas in Japan.http://josen.env.go.jp/en/pdf/environmental_remediation_1901.pdf. Accessed 14 June 2019
Shin M, Kubota T, Manpuku Y, Suzuki Y, Yasutaka T, Matsunami H, Ota T (2019) Behavior of radiocesium in decontaminated paddy fields in Fukushima Prefecture, Japan, Paddy Water Environ. https://doi.org/10.1007/s10333-019-00694-6
Shin M, Kubota T, Miyazu S, Hikigi S, Lee S (2018) Efforts utilized ICT towards Safety and Security of Irrigation Water in Fukushima Disaster Area, Water Land Environ Eng 86(4):281–284 (in Japanese)
1 Associate Professor, Faculty of Food and Agricultural Sciences, Fukushima University, Fukushima 960-1296, Japan
2 Head, Hydrology and Water Resources Unit, Institute for Rural Engineering, NARO, Tsukuba 305-8609, Japan
3 Assistant Professor, Institute of Science and Technology, Niigata University, Niigata 950-2181, Japan
4 Researcher, Hillside Disaster Prevention Group, Western Region Agricultural Research Center, NARO, Kagawa 765-0053, Japan