Deposition density of Cs-134 and Cs-137 and particle size distribution of soil and sediment profile in Hibara Lake area, Fukushima: an investigation of Cs-134 and Cs-137 indirect deposition into lake from surrounding area

摘要

Indirect deposition process of Cs-134 and Cs-137 beyond river system into Hibara Lake, Fukushima was investigated by analyzing the deposition density of Cs-134 and Cs-137 and particle size distribution of soil and sediment. Sediment samples of shallow area of lake adjacent to catchment with different slope were used. The sediment depth profile comparison among sampling areas showed faster Cs-134 and Cs-137 indirect deposition rate in sediment near steep slope area. Cs-134 and Cs-137 were concentrated dominantly in fine particle, indicating that the Cs-134 and Cs-137 incorporated to fine particle were dominant species in indirect deposition process.