(中南大學(xué)資源與安全工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 為評(píng)估尾砂礦生態(tài)風(fēng)險(xiǎn)，保護(hù)生態(tài)環(huán)境，實(shí)現(xiàn)可持續(xù)發(fā)展，研究某鉛鋅尾礦庫(kù)中Pb、Zn、Cu、As4種重金屬的垂向分布并對(duì)其污染程度和潛在生態(tài)危害進(jìn)行評(píng)價(jià)。除使用地累積指數(shù)法和生態(tài)風(fēng)險(xiǎn)指數(shù)法，結(jié)合地累積指數(shù)法和內(nèi)梅羅綜合指數(shù)法來(lái)評(píng)價(jià)多種重金屬綜合污染情況。結(jié)果表明：重金屬在垂向上的分布不盡相同，復(fù)墾土層重金屬含量較下層小但仍超過(guò)土壤背景值；土層與尾砂交界處，重金屬出現(xiàn)富集現(xiàn)象，污染程度最大；尾砂層和深部區(qū)為中度或強(qiáng)污染。4種重金屬元素Cu的污染最輕，Pb、Zn、As的在中度污染或強(qiáng)污染以上，對(duì)總的生態(tài)風(fēng)險(xiǎn)指數(shù)貢獻(xiàn)率由大到小依次為As、Pb、Zn、Cu。單純覆土對(duì)減少尾礦庫(kù)重金屬危害效果不明顯，應(yīng)聯(lián)合其他有效措施進(jìn)行修復(fù)。
關(guān)鍵字: 尾礦庫(kù)；復(fù)墾；重金屬污染；生態(tài)風(fēng)險(xiǎn)評(píng)價(jià)
（School of Resources and Safety Engineering, Central South University, Changsha 410083, China）
Abstract:In order to assess the ecological risk of tailings, protect ecological environment and achieve sustainable development, the vertical distribution characters of the heavy metals Pb, Zn, Cu and As in a tailings were investigated, and the pollution and potential ecological hazards degree were assessed. In addition to geoaccumulation index and ecological hazards index, thegeoaccumulation index and Nemerow index were combined to evaluate the comprehensive pollution of heavy metals. The results show that the vertical distributions of heavy metals are different. The heavy metal concentration in the reclamation soil is lower but it is still higher than the soil background value. The heavy metal concentration in the interface between the soil and tailings is the highest, the pollution degree is the strongest. The pollution degrees in the tailings layer and deep area are more severe. Among these heavy metals, the pollution degree of Cu is the slightest, and the pollution degrees of Pb, Zn and Asare different in different depth. The contribution orders of the four heavy metals on the total ecological hazards index from big to small are As, Pb, Zn, Cu. The effect that simple covering soil on tailings to reduce heavy metal hazards is not significant, other effective measures should be combined to treat heavy metal pollution.
Key words: tailings; reclamation; heavy metal pollution; ecological hazards assessment
