Contribution of fungal hyphal elongation to radiocesium transfer in deciduous broad-leaved litter

Sasaki, Yoshito ; Niizato, Tadafumi  ; Amamiya, Hiroki*; Yoshida, Kaori 

Radiocesium deposited in the forest released by the accident at the Fukushima Daiichi Nuclear Power Station would remain in the forest and part of it would circulate due to the small amount of outflow from the forest. One possible source of dissolved radiocesium that is easily taken up by organisms is the litter layer. To clarify the contribution of fungal mycelial elongation in the transfer of radiocesium in the litter layer, we investigated the effect of the presence of fungi on the transfer of radiocesium from litter Cs(H) with high radiocesium concentration to litter Cs(L) with low radiocesium concentration. Fungal growth was observed in the test plots where the fungi were present. Regardless of with or without fungi, the Cs-137 concentration of Cs(L) reached about 50 Bq/kg on the 50th day, and then gradually increased to about 100 Bq/kg on the 150th day. This result suggested that the radiocesium was transferred by a physical force other than the hyphal elongation of the fungus in the litter layer.