장항제련소 지역의 토양과 수도체중 Cd 및 Zn 함량의 변화 = Originals : Variation of Cadmium and Zinc Content in Paddy Soil and Rice from the Janghang Smelter Area

다국어 초록 (Multilingual Abstract)

To investigate differences in Cd and Zn contents in paddy soils and rice plants polluted by aerial emissions from the Janghang smelter, soil samples in the different directions and at the surface (0-15㎝) and subsurface (15-30㎝) in 1982 and 1990, and rice plants at the corresponding sampling sites in 1990 were collected from the Janghang Smelter Area. Soil samples were extracted with 4M-HNO₃ and plant samples were digested with a mixture of HNO₃ and HClO₄for analyzing by atomic absorption spectrophotometry. The Cd and Zn contents in soils ranged from 0.09 to 4.42 and from 16.0 to 959.5㎎ ㎏^(-1), respectively. The average contents of Cd and Zn in 1990 were higher than those in 1982. The Cd and Zn contents of soils near the center of the smelter were higher than those of soils farther from the center and also decreased in the order of east > north-north east > north east > north. The Cd and Zn levels in surface soils were higher than those in subsurface soils. The contaminated areas of Cd and Zn were within 4㎞ in the east, and within 3㎞ in the north-north east and the north east. Metal contents in brawn rice were the lowest in rice plants. The Cd content of brown rice was one sixth of that in leaf blade and in leaf sheath. The Cd content of leaf blade, stem and panicle axis were significantly correlated with the levels of Zn, Cu and Pb in soils, and Zn content of stem was significantly correlated with the levels of Cu and Pb. The Cd and Zn content in brown rice ranged from 0.05 to 0.25㎎ ㎏^(-1) and from 10.5 to 30.9㎎ ㎏^(-1) in the smelter area, respectively.