Assessment of suspended sediment and Cs sources during the flood event in the Fukushima river using C and C

Nakanishi, Takahiro   ; Tsuruta, Tadahiko  ; Funaki, Hironori 

In this study, the radiocarbon isotope ratio, C, was used to identify the sources of suspended sediment and Cs discharged into rivers after the Fukushima nuclear accident. Suspended sediments were collected during the flood event and under normal water conditions to determine Cs concentrations, C, and stable carbon isotope ratios. The results indicated that the contribution of forest surface soil runoff increased during the flood peak. Furthermore, the distribution of Cs deposition in the watershed was reflected in temporal changes in suspended Cs concentration during the flood event. This approach provides a comprehensive understanding of both Cs and carbon dynamics.