아연광산(亞鉛鑛山) 주변(周邊)에서 답토양(畓土壤)과 현미(玄米) 36점을 채취(採取)하여 축차분별분석(逐次分別分析)에 의해 토양(土壤) 중(中) Cd, Zn, Cu 및 Pb의 각(各) 형태별(形態別) 함량비(含量比)를 구하고, 중금속(重金屬)의 형태(形態)에 미치는 토양(土壤) 특성(特性)과 수도(水稻)의 흡수(吸收)와 관계가 깊은 화학적(化學的) 형태(形態)를 밝히기 위해 실험(實驗)하였다. 토양(土壤) 중(中) Cd의 형태별(形態別) 함량(含量)은 치환태(置煥態), 유기태(有機態) 및 carbonate 태가(態) 거의 같았으며 전(全) Cd의 73.9%를 차지하였다. 토양 중(中) Zn,은 잔류성(殘留性) Zn이 63.8%로 가장 높았다. Cu와 Pb의 형태별(形態別) 함량비(含量比)의 순위(順位)는 비슷하였다. 토양(土壤)의 pH가 높을수록 치환태(置換態) Cd, Zn, 및, Pb는 감소(減少)하였으며, 유기태(有機態)와 carbonate 태(態), Cd, sulfide 태(態) Cd, Zn, 및 Pb는 증가(增加)했다. 토양(土壤) 중(中) 유기물함량(有機物含量)은 유기태(有機態) Cd, Zn, 및, Pb는 carbonate 태(態) Cu와 정(正)의 상관(相關)을 보였다. 양(陽)이온치환용량(置換容量)이 증가(增加)하면 치환태(置換態) Cd, Zn, Cu 및, Pb, 유기태(有機態) Cu는 감소(減少)하였으나 carbonate 태(態) Cd, sulfide 태(態) Cd, Zn, Cu 및, Pb, 잔류성(殘留性) Cu는 증가(增加)하였다. 현미(玄米) 中 Cd 함량(含量)은 토양(土壤) 중(中) 전(全) Cd, 유기태(有機態) Cd, carbonate 태(態), sulfide 태(態) Cd 및 잔류성(殘留性) Cd와 높은 정(正)의 상관(相關)을 보였다. 그러나 토양(土壤) 중(中) Pb는 어떠한 형태(形態)도 현미(玄米) 중(中) Pb 함량(含量)과 상관(相關)이 없었다. 토양(土壤) 중(中) 수용태(水溶態)와 치환태(置換態) Zn 함량(含量)은 현미(玄米) 중(中) Zn 함량(含量)과 높은 정(正)의 상관(相關)을 보였다.
Soil samples collected from paddy field adjacent to zinc-mining sites were sequentially extracted to assess chemical fractions of Cd, Zn, Cu and Pb. The purpose of this study was two fold; (i) to examine the chemical forms of heavy metal in soils by sequential extraction. and (ii) to determine relationships between the chemical distribution of heavy metal in the soil and the heavy metal content of the brown rice. The results are summarized as follows. The content of exchangeable, organically bound and carbonate Cd and residual Zn was 73.9% and 63.8% of total Cd and Zn in the soil, respectively. The content of exchangeable Cd, Zn and Pb in soil showed highly negative correlations with pH, organically bound Cd, carbonate Cd, sulfide Cd, Zn and Pb in soil showed highly positive correlations with pH. The content of organically bound Cd, Zn, Pb and carbonate Cu in soil showed highly positive correlations with organic matter content, while the content of sulfide Cu and residual Cd in soil showed highly negative correlation with organic matter content. The content of carbonate Cd, Zn, Pb and residual Cu in soil showed highly positive correlations with CEC, but the content of exchangeable Cd, Zn, Cu, Pb and organically bound Cu in soil showed highly negative correlations with CEC. The content of total, organically bound, carbonate, sulfide and residual Cd in soil were highly correlated with that of Cd in brown rice. The content of any Pb fractions in soil were not correlated with that of Pb in brown rice. The content of water soluble and exchangeable Zn in soil were highly correlated with that of Zn in brown rice.
