Factors controlling dissolved 137 Cs activities in Matsukawa-ura lagoon, a semi-closed estuary, after the Fukushima accident
Abstract
Abstract. The spatial and seasonal dynamics of 137Cs were investigated from 2021 to 2023 in Matsukawa-ura lagoon, a semi-closed estuarine area approximately 40 km north of the Fukushima Daiichi Nuclear Power Plant, Japan. Weighted mean dissolved 137Cs concentrations in the lagoon waters ranged from 5.3 to 19 Bq m-3, 2.4–8.6 times higher than those in the surrounding coastal seawater and inflowing river waters. Mass balance calculation suggests that the dissolution of 137Cs from bottom sediments sustained the high dissolved 137Cs concentrations in the estuarine water. Furthermore, dissolved 137Cs concentrations in the lagoon were higher in summer (July) than in winter (February). Quantification of the source revealed that dissolution caused 137Cs concentrations in bottom sediments to decrease by more than 2.4 % over 30 days in July, but only by
Fields of Study & Subjects
Radioactive contamination and transfer
Publication details
- Journal / source
- Biogeosciences
- Publisher
- Copernicus GmbH
- Volume
- 23
- Issue
- 10
- Pages
- 3591–3604
- Publication date
- 26 May 2026
- Language
- EN