大氣 및 水質汚染地域의 土壤 및 水稻體中 重今屬含量에 科한 硏究 = Studies on the Heavy Metals on Paddy Rice and Soils in Janghang Smelter and Mangyeong River Area

국문 초록 (Abstract)

長項製鍊所의 排煙과 全州市 工團廢水 및 都市下水의 影響을 받는 地域의 土壤과 水稻를 對象으로 Cd, Cu, Pb 및 Zn 등 重金屬含量을 調査分析하는 한편 pot 試驗을 通하여 이들 重金屬이 水稻生肉 및 收量에 끼치는 影響을 調査하기 위하여 pot 試驗을 修行하였던 바 그 結果를 要約하면 다음과 같다.
1. 製鍊所의 排氣에 依한 東쪽 方向에서 가장 甚하였고 Pb의 天然賦存量을 基準으로 하였을 때 汚染距離는 5km이었으며 表土에 많이 蓄積되고 있었고, 工團廢水 및 都市下水에 의한 土壤의 重金屬含量은 表土와 心土間의 差異가 거의 없었다.
2. 土壤中 各 重金屬의 全含量에 對한 0.1N-HCl 및 N-NH?Ac에 의한 溶出率은 製鍊所 周邊 土壤의 것이 萬頃江 土壤의 것보다 높았다.
3. 土壤中 有機物含量 및 陽ion置換容量과 重金屬全含量間에는 有意性 있는 相關을 나타냈다.
4. 製鍊所周邊 土壤에서 생산된 玄米中의 重金屬含量은 Cd가 0.23~1.33, Cu은 2.39~6.25, Pb은 0.95~8.32, Zn은 14.60~27.31ppm였으며 工團廢水 및 都市下水에 의해서 汚染된 ?土壤에서 生産된 玄米中 重金屬含量은 Cd은 0.15~0.91, Cu은 1.13~5.68, Pb은 0.22~7.16, Zn은 11.74~38.66ppm이었다.
5. 水稻體의 ?葉部位와 玄米中 重金屬含量間에는 兩汚染源 모두 Cd, Cu, Zn은 有意性있는 正의 相關을 보였다.
6. 水稻의 chlorosis玄裳은 Ni, Cr은 30ppm以上의 處理濃度에서 나타났고, Cu은 30ppm以上, Cd와 Pb는 100ppm濃度에서 若干의 生育抑制가 있었으나 Zn은 100ppm 濃度에서도 生育 障碍가 없었다.
7. 水稻의 收量은 Cr과 Ni은 12ppm, Cu은 30ppm, Cd와 Pb은 100ppm의 處理濃度에서 有意性있는 收量減少를 보였으나 Zn은 本 實驗의 最高濃度인 100ppm 處理에서도 有意性이 없었다. 收穫後 水稻의 ?葉部에서의 각 重金屬含量은 生育中期에 比하여 크게 減少되었다.
8. 長項 및 萬頃江流域等 兩重金汚染地의 土壤 및 水稻中 重金屬含量은 水稻生育 및 收量에 影響을 줄 程度는 아니었다.

다국어 초록 (Multilingual Abstract)

Soils and rice plants subject to smoke from the janghang smelter and polluted water of the Mangyeong River receiving waste water from the Jeonju Industrial Complex were samples at two depths to assess the nature and extent of Cd, Cu, Pb, and Zn contamination, particularly with respect to distance from pollution source.
Possible effects of heavy metal contamination on rice growth were checked through pot experiments with different concentrations of heavy metals.
Soils at east site within 1km of' the center of the smelter were highly contaminated with Cd, Cu, Pb, and Zn. Metal levels in the smoke-polluted area were higher in surface soil than in subsurface soil, and decreased rapidly with distance reaching nearly background levels at 5km from pollution source. For metal levels of soils in the Mangyeong River area, no difference in the heavy metal contents between the surface and subsurface soils was found.
Metal levels in soils distributed along the Mangyeong River were found to be lower than levels in soils polluted by the smoke from the Janghang Smelter.
A positive correlation was between contents of total and 0.1N HCI-extractable, or 1.0N CH?COONH?-extractable heavy metals regardless of the pollution source.
Contents of heavy metals in soils were positively correlated with soil organic matter and cation exchange capacity irrespective of the pollution source.
The contents of heavy metals in brown rice collected from the pappy field around the Janghang Smelter were in the range 0.23~1.33 ppm for Cd, 2.39~6.25 ppm for Cu, 0.95~8.32 ppm for Pb and 14.60~27.31 ppm for Zn. Heavy metal contents of brown rice sampled at the Jeonju Industrial Complex area ranged from 0.15 to 0.91 ppm for Cd, from 1.13 to 5.68 ppm for Cu, from 0.22 to 7.16 ppm for Pb, and from 11.74 to 38.66 ppm for Zn.
Regradless of the source of pollution, the contents of Cd, Cu, and Zn in rice straw were positively correlated with those in the brown rice. Negative correlation was found between the contents of Cd, Cu, Pb, and Zn in brown rice and the distance from the source.
Ni and Cr cause chlorosis in rice at 30 ppm. The rice was retarded by 30 ppm of Cu and 100 ppm of Cd and Pb, whereas no phytotoxicity was observed with 100 ppm off Zn.
Phytotoxicity caused by Ni, Cr, Cd, and Cu increased with increasing the application rate of heavy metals, while no correlation was obtained with 100 ppm of Zn and Pb, respectively. For heavy metals studied, the content was greater in rice roots than in rice straw.
A significant yield reduction occurred at 12 ppm of Cr and Ni, 30 ppm of Cu and 100 ppm of Cd and Pb. No yield reduction was found at 100 ppm of Zn. Content of the heavy metals in rice straw sampled at harvest was lower than that sampled during vegetative stage and the content in brown rice was 5 to 46% of that in rice straw, indicating less translocation of the heavy metals from the rice straw to the grain.