Biological proliferation of cesium-137 through the detrital food chain in a forest ecosystem in Japan

Radionuclides, including ¹³⁷Cs, were released from the disabled Fukushima Daiichi Nuclear Power Plant and had been deposited broadly over forested areas of north-eastern Honshu Island, Japan. In the forest, ¹³⁷Cs was highly concentrated on leaf litters deposited in autumn 2010, before the accident. Monitoring of the distribution of ¹³⁷Cs among functional groups clearly showed the role of the detrital food chain as the primary channel of ¹³⁷Cs transfer to consumer organisms. Although many studies have reported the bioaccumulation (or dilution) of radioactive materials through trophic interactions, the present results highlight the importance of examining multiple possible pathways (e.g., grazing vs. detrital chains) in the proliferation of ¹³⁷Cs through food webs. These results provide important insight into the future distribution and transfer of ¹³⁷Cs within forest ecosystems.