1. Thirty-Year Prediction of 137 Cs Supply from Rivers to Coastal Waters off Fukushima Considering Human Activities.
- Author
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Ikenoue, Tsubasa, Shimadera, Hikari, Nakanishi, Takahiro, and Kondo, Akira
- Subjects
TERRITORIAL waters ,NUCLEAR power plant accidents ,COASTAL sediments ,CESIUM ions ,CESIUM ,WATERSHEDS ,RADIOACTIVE fallout - Abstract
The Fukushima Daiichi Nuclear Power Plant accident caused an accumulation of
137 Cs in coastal sediment. The137 Cs supply from rivers to the ocean can affect the long-term fate of137 Cs in coastal sediment. Since the Fukushima coastal river basins include large decontaminated and evacuation order areas, considering the decontamination work and resumption of agriculture is important for predicting the137 Cs supply. We conducted a 30-year prediction of the137 Cs supply from the Fukushima coastal rivers to the ocean using a distributed radiocesium prediction model, considering the effects of human activities. In river basins with decontaminated and evacuation order areas, human activities reduced the total137 Cs outflow from agricultural lands, urban lands, and forest areas to the rivers and the137 Cs supply to the ocean by 5.0% and 6.0%, respectively. These results indicated that human activities slightly impacted the137 Cs outflow and supply. The137 Cs supply from rivers impacted by the accident to the coastal sediment was estimated to correspond to 11–36% of the total137 Cs in the coastal sediment in the early phase of the accident. Therefore, the137 Cs supply from rivers to the ocean is important for the long-term behavior of137 Cs in coastal sediment. [ABSTRACT FROM AUTHOR]- Published
- 2023
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