Screening plant species native to Taiwan for remediation of 137Cs-contaminated soil and the effects of K addition and soil amendment on the transfer of 137Cs from soil to plants

This study aims to screen plant species native to Taiwan that could be used to eliminate 137Cs radionuclides from contaminated soil. Four kinds of vegetables and two kinds of plants known as green manures were used for the screening. The test plants were cultivated in 137Cs-contaminated soil and amended soil which is a mixture of the contaminated one with a horticultural soil. The plant with the highest 137Cs transfer factor was used for further examination on the effects of K addition on the transfer of 137Cs from the soils to the plant. Experimental results revealed that plants cultivated in the amended soil produced more biomass than those in the contaminated soil. Rape exhibited the highest production of aboveground parts, and had the highest 137Cs transfer factor among all the tested plants. The transfer of 137Cs to the rape grown in the soil to which 100 ppm KCl commonly used in local fertilizers had been added, were restrained. Results of this study indicated that rape, a popular green manure in Taiwan, could remedy 137Cs-contaminated soil.