Sedimentation and remobilization of radiocesium in the coastal area of Ibaraki, 70 km south of the Fukushima Dai-ichi Nuclear Power Plant
書誌事項
- 公開日
- 2012-11-13
- 権利情報
-
- http://www.springer.com/tdm
- DOI
-
- 10.1007/s10661-012-2956-7
- 公開者
- Springer Science and Business Media LLC
この論文をさがす
説明
Sedimentation and remobilization processes of radiocesium were investigated from time-series observations at nine stations in the coastal area of Ibaraki, 70-110 km south of the Fukushima Dai-ichi Nuclear Power Plant (1FNPP). Sediment samples were collected four times between June 2011 and January 2012, and concentrations of radiocesium as well as sediment properties such as grain size and elemental compositions were analyzed. Cumulative inventory of (137)Cs in sediment (0-10 cm) ranged between 4 × 10(3) and 3 × 10(4) Bq/m(2) as of January 2012. This amount was generally higher at stations nearer 1FNPP and has remained at the same level since August 2011. From these results, it can be inferred that dissolved radiocesium advected southward from the region adjacent to the 1FNPP and was deposited to the sediment of the study area in the early stage after the accident. The incorporation of radiocesium into sediments was almost irreversible, and higher concentrations of (137)Cs were obtained from the finer-grained fraction of sediments. In the northern offshore stations, resuspension of the fine-grained sediments formed a high-turbidity layer 10-20 m above the seabed. These results indicate that radiocesium-enriched fine particles were transported from the coast to offshore regions through the bottom high-turbidity layer.
収録刊行物
-
- Environmental Monitoring and Assessment
-
Environmental Monitoring and Assessment 185 (7), 5419-5433, 2012-11-13
Springer Science and Business Media LLC