Modeling long-term transfers of radiocesium in farmland under different tillage and cover crop treatments.

The 2011 nuclear accident at Japan's Fukushima Daiichi Nuclear Power Plant (FDNPP) prompted inquiries about the long-term transfer of Cesium-137 (Cs) from soil to agricultural plants. In this context, numerical modeling is particularly useful for the long-term evaluation of the consequences of agroecosystem contamination. Agricultural practices, such as tillage and cover cropping, play key roles in Cs recycling in agroecosystems.

Radiocesium distribution caused by tillage inversion affects the soil-to-crop transfer factor and translocation in agroecosystems.

This study reports the translocation of cesium-137 (Cs) into deep soil layers, and the Cs transfer from soil to soybean in farmland under three tillage (no tillage, NT; rotary cultivation, RC; moldboard plow; MP) treatments and an undisturbed grassland (GL) at eight years after the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident on 11 March 2011 in Japan. Tillage influences the Cs distribution in the 0-30 cm of soil; the distribution of Cs in the soil was uniform under RC and MP treatments, while in the grassland, most Cs was concentrated on the soil surface (0-2.5 cm).

Temporal dynamics of Cs distribution in soil and soil-to-crop transfer factor under different tillage systems after the Fukushima Daiichi Nuclear Power Plant accident in Japan.

The accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) in Japan in 2011 released a large amount of radionuclides, primarily radiocesium-137 (Cs; half-life: 30 years), resulting in long-term contamination of soil and consequently crops. Tillage is a common agricultural management practice that alters the vertical distribution of nutrients in the soil. However, the effect of tillage on Cs contamination in soil and crops over time remains unclear.