Abstract
Radionuclide substances in the Japanese environment need to be monitored, after the contamination caused by the Fukushima Daiichi Nuclear Power station accident. In this study, we focused on the sampling methods used for sediments in lakes. We investigated radioactive concentrations of 134Cs and 137Cs in lakes sediments found in Fukushima prefecture using two types of sediment samplers, the grab and core sampler. The sampling points were the same as those used in the Lake Akimoto and Numasawa study of 2013. Thereafter, we compared that study's data with our grab and core samples. We obtained the concentration and type of radioactive Cs in the sediment with core samples and estimated the depth of the sediment samples with the grab sampler. The concentrations of Cs in the sediment samples taken with the grab samplers were underestimated, because the radioactive Cs was detected in the surface sediment samples using the core sediment sampler. Since appropriate sediment sampler selection is clearly important, we suggest using the core sampler for the sampling of particular radionuclides substances in the sediment.
