EAPSI: Radiocesium Soil-to-Plant Transfers in Fukushima Forests

Workman Daniel, Fort Collins CO

Investigators

Abstract

This project aims to increase understanding of the transport of radioactive contaminants in the forests surrounding the Fukushima Prefecture of Japan. Radioactive forms of cesium were deposited in the surrounding forests and environment following the accident at the Fukushima Dai-ichi Nuclear Power Plant on March 11, 2011. This research will be conducted at the Institute of Environmental Radioactivity (IER), which is hosted at Fukushima University, Fukushima City. Gaining a deeper understanding of the ongoing effects of the disaster is key for the study and development of environmental policies in both the US and Japan. Studies will be performed in collaboration with Dr. Vasyl Ioshchenko, an expert on environmental radiocesium with extensive experience studying radioactivity in the environment surrounding the Chernobyl accident site. As radiocesium can remain in the environment for many years this study will also contribute to the cleanup efforts in Japan. Data will be developed by sampling soil and vegetation in five different experimental plots within Fukushima prefecture and within the exclusion zone. The plots will represent a range of radiocesium soil concentrations. Three understory plant species will be sampled and the vertical distribution of the roots in the soil profile will be measured within each plot. Soil samples will be collected to determine vertical distribution of bioavailable radiocesium within the root profile of a sampled plant species. Following sequential extraction to separate bioavailable forms of radiocesium, the samples of soil and vegetation will be analyzed for radiocesium content by gamma spectroscopy. The resulting radiocesium concentration and distribution data will be the basis for a mechanistic interpretation of the soil-to-plant transfer factors for the sampled species. Understanding radiocesium behavior in the forest ecosystem is essential for the development of long-term forest management strategy and the clarification of long-term radiation risks. This award, under the East Asia and Pacific Summer Institutes program, supports summer research by a U.S. graduate student and is jointly funded by NSF and the Japan Society for the Promotion of Science.