CAJ | 학술논문

应用地累积指数法和生态危害指数法对汉江上游某铁矿尾矿库区周边土壤重金属污染特征和潜在生态环境污染风险进行了研究。结果表明尾矿库区土壤中重金属除Ti外均超出当地土壤背景值，以Cd超标最严重（超标12倍）；形态分析表明Fe、Ti、As、Hg的主要存在形态是残渣态，Mn的可交换态和碳酸盐结合态所占比例最高（均值24.07％），Zn的易还原态所占比例最高（均值22.07％），Ni和Co的易氧化态所占比例最高（均值分别为28.99％、25.46％）；地累积指数法评价表明尾矿库区土壤Hg和Cd达到中-强污染等级，As和Co属中度污染等级，Fe、Zn、Mn、Ni以无污染-中污染为主，其余金属无污染；生态危害指数法结果显示Cd和Hg的生态风险等级为极强，As生态风险等级为中等，其余元素生态风险等级为轻微，尾矿库采样区域整体处于很强的生态风险等级，尤其需要加强对Cd、Hg、As的污染防治。
응용지루적지수법화생태위해지수법대한강상유모철광미광고구주변토양중금속오염특정화잠재생태배경오염풍험진행료연구。결과표명미광고구토양중중금속제Ti외균초출당지토양배경치，이Cd초표최엄중（초표12배）；형태분석표명Fe、Ti、As、Hg적주요존재형태시잔사태，Mn적가교환태화탄산염결합태소점비례최고（균치24.07％），Zn적역환원태소점비례최고（균치22.07％），Ni화Co적역양화태소점비례최고（균치분별위28.99％、25.46％）；지루적지수법평개표명미광고구토양Hg화Cd체도중-강오염등급，As화Co속중도오염등급，Fe、Zn、Mn、Ni이무오염-중오염위주，기여금속무오염；생태위해지수법결과현시Cd화Hg적생태풍험등급위겁강，As생태풍험등급위중등，기여원소생태풍험등급위경미，미광고채양구역정체처우흔강적생태풍험등급，우기수요가강대Cd、Hg、As적오염방치。
The distribution characteristics and potential ecological risk of heavy metals in soils surrounding an iron tailings in the upstream areas of Hanjiang River, Shaanxi Province were investigated. The geoaccumulation index and the ecological risk index were calculated to as-sess the heavy metal pollution levels. The concentrations of metals in the soils were higher than their background values, except Ti. Chemi-cal fractionation showed that Fe, Hg and As were mostly associated with residual fraction(over 80%), whereas the residual fraction for the other metals was only about 50%. However, the other fractions for Cd, Mn, Ni, and Zn were relatively high. Mn was averagely 24.07%in ex-changeable and 17.2%in reducible fractions, Zn 22.07%associated with reducible fraction and 16.1%with oxidizable fraction, Ni 28.9%with oxidizable fraction and 21.8% with reducible fraction, and Cd 22.8% with oxidizable fraction and 18.5% with reducible fraction. Co was 25.5%, 18.6%, and 18.4%in oxidizable, exchangeable, and reducible fractions, respectively. The geo-accumulation index indicated that these soils were at moderate to severe pollution by Hg and Cd, moderate pollution by As and Co, and no to moderate pollution by Fe, Mn, Ni, and Zn. The ecological risk index showed that Cd and Hg had the highest ecological risk and As was at moderate ecological risk, while other elements had slight ecological risk. In summary, the studied area showed higher ecological risk of heavy metals. Appropriate measures should be taken to protect the soils from heavy metal pollution, particularly Cd, Hg, and As.