2016 Volume 98 Issue 3 Pages 128-131
After the accident at the Fukushima Daiichi Nuclear Power Plant in March 2011, radiocesium concentration in the fruiting body of Pholiota microspora showed a higher trend than those in the fruiting body of other mushroom species in the open bed-log cultivation. Therefore, we started a bed-log cultivation experiment with Pholiota microspora using Chamaecyparis obtusa wood at the beginning of April 2013 in Tokigawa Town, Saitama Prefecture. In each of the 5 different forest sites, we established 3 plots: 1） non-processed plot （control）, 2） topsoil （0-5 cm） removal plot, and 3） bed-log covered with cheesecloth plot. The fruiting bodies were harvested in October and November 2014. In a fresh fruiting body harvested from one bed-log in the non-processed plot, 134+137Cs concentration was 45 Bq/kg, but the mean value of the non-processed plot was 13 Bq/kg. Therefore, fruiting bodies harvested there were safe to be consumed as food. 134+137Cs concentration in the fresh fruiting bodies grown in the topsoil removal plot was significantly different from that in fruiting bodies grown in the other plots; it was 36% lower than that in the non-processed plot. The 134Cs/137Cs ratio in the fruiting body was similar to that of the radiocesium derived from the accident and that in the litter layer, but was different from that in the soil and the log.
