Recovering Soil Fertility After Stripping the Cs Contaminated-Top Soil Off At Iitate Village in Fukushima Prefecture.

Iitate Village was once named as one of the most beautiful villages in Japan by an association of NPO groups. An agricultural prosperous layer in agricultural fields was contaminated by radionuclides, e.g., 134-Cs, 137-Cs, and 90-Sr, just after the accident of the Fukushima Daiichi Nuclear Power Plant in 2011. Although farmers in Iitate Village had lived together with nature in harmony for centuries, they have been forced to evacuate from their home ever since after the accident. The farmers and villagers successfully established sustainable societies in Iitate Village with natural farming and recycling communities. Living in such societies is called “madei” life, in which “madei”, a dialect of Iitate Village, means that when villagers do something good to others, the villagers hope others’ happiness with respect and whole heart. The “madei” brand is labelled to products yielded under such consideration. Decontamination work for agricultural fields contaminated with the radionuclides has been continued to strip off the top soil in Iitate Village since 2011. Decontamination by stripping the top soil off may attribute to decreases in soil fertility. We will incorporate the natural breakdown of organic matter to quickly recover the fertile top soil in agricultural fields. We will transplant rice crop in the two treatments of paddy fields with and without rice straw harvested last year in Iitate Village to build a recycling farming system. Transfer rate of the radionuclides from the rice straw harvested last year to new rice crop will be determined using a germanium semiconductor detector. We will compare rice crop yields and soil fertility between two treatments, i.e. soil nitrogen and phosphorus level, soil organic matter content, soil hardness and etc. We will show the situation of the present progressive our trial.