토양에 적용된 안정화공법은 대조구에 비해 높은 수준의 안정화 효율성을 나타냈으며, 안정화 후 유효태 중금속함량의 경우 적용된 추출기법에 따라 많은 차이가 있는 것으로 평가되었다. 그렇지만, 토양의 안정화는 평가기법별로 농도의 차이는 있지만 식물 유효태를 감소시킬 수 있다는 결론을 얻었다. 농작물로의 전이량은 0.1 M HCl, 5 mM DTPA와 분획화 시험법이 높은 상관관계를 나타내었다. 하지만 토양의 특성이 고려되지 않고 단지 중금속의 농도만을 고려한 시험이었기에 향후 다양한 토양의 이화학적 인자값을 평가하여 심도 깊은 연구가 진행되어야 할 것으로 사료된다.
Crop safety in heavy metal contaminated agricultural field has been a critical issue in Korea and various remediation methods are proposed for minimizing heavy metal transfer from soil to crops. The main objective of this research was to evaluate remediation efficiency of two chemical amendments, lime and steel slag, and to decide extractant for assessing bioavailability of heavy metals. In order to select optimum extractant for evaluating bioavailability of heavy metals, four different single extractants, HCl, DTPA, $CaCl_2$, $NH_4NO_3$, and sequential extraction method were examined. Both chemical amendments showed high immobilization effect for Cd (66%, $33.62mg;kg^{-1}$) and Pb (74%, $27.65mg;kg^{-1}$) in soil by HCl extractant. In terms of heavy metal concentration in rice grains, concentrations for Cd (77%, $0.023mg;kg^{-1}$) and Pb (82%, $0.039mg;kg^{-1}$) decreased, with addition of chemical amendments. HCl, DTPA, and sequential extractant showed the higher correlation between heavy metal concentration in soil and crops than others. These results indicated that they could be used for assessing bioavailability of heavy metals.
