Application Of Chemical Amendments For Reducing Bioaccumulation Of Heavy Metal In Agricultural Field, Korea.

Rice cultivation in heavy metal contaminated field becomes a critical issue in Korea due to bioaccumulation of heavy metals in rice grain. Among other remediation techniques, application of chemical amendments in heavy metal contaminated agricultural field has been utilized for reducing biological transport of pollutants from soil to crops. Therefore, main objective of this research was to evaluate application of chemical amendments and green manure on reduction of biological transport of heavy metals from soil to crop. Chemical amendments, lime and steel slag, were amended solely with heavy metal contaminated agricultural soil and combined amendment with green manure crops. Cadmium (Cd) concentration in soil was monitored during rice cultivation period and Cd concentration of rice was measured after harvesting. During experimental period, Cd concentration in soil was lowered at the range of 43-67%, 21-42%, 34-66%, 10-40% for lime, steel slag, lime+green manure, and steel slag+green manure respectively comparing to control (1.18 mg/kg with 0.1N HCl extraction). Cadmium concentration in rice grain was ranged 23 – 45 µg/kg depending on varied treatment. Based on Cd concentration in soil and rice grain, biological transport factor (BTF) of Cd was calculated at the range of 0.036-0.064. Among varied treatments, lower BTF value was calculated at the order of steel slag (0.036) > green manure (0.038) > Lime (0.055) > Lime + green manure (0.058) > steel slag + green manure (0.064) > control (0.083). Overall, application of chemical amendments in heavy metal contaminated soil is a feasible technique for reduction of contaminants and can be utilized in agricultural field for remediation purpose.

Keywords: Heavy metal, Cadmium, Agricultural field, Rice, Biological transport factor (BTF)