【摘要】 云南金顶铅锌矿是镉元素富集区,采矿活动导致镉元素释放出来进入地表环境造成镉污染。矿区不同岩石中镉分布差异比较大,围岩中镉含量范围在50×10-6~650×10-6之间,平均310×10-6,原生矿中镉含量范围14×10-6~2800×10-6,平均767×10-6,氧化矿中镉含量范围110×10-6~8200×10-6,平均1661×10-6,其平均值最高。氧化矿是镉元素的主要载体和释放源。淋滤实验表明矿石易氧化而释放出镉等有害元素,滤出元素可以迅速发生沉淀或被沉淀物包裹,其能力表现为Zn>Pb>Cd。研究结果表明,矿区下游江河段水体中隔的平均值为15.7μg/L,悬浮物中镉平均值为49.3 mg/kg,沉积物中镉平均值为203.7 mg/kg。矿区富镉岩石和矿物的自然风化是造成江水体和沉积物中镉污染的直接原因,对流域水生态环境造成潜在危害。更多还原

【Abstract】 The Jinding Pb-Zn deposit in Yunnan is rich in cadmium,and mining activity is ready to facilitate cadmium to release into the hypergene ecosystem.Concentration distribution of cadmium varies in different rocks in the mining district.In the host rocks,cadmium concentrations range from 50×10-6 to 650×10-6 with an average of 310×10-6.In primary ores,cadmium concentrations range from 14×10-6 to 2800×10-6 with an average at 767×10-6.However,in oxidized ore,cadmium is of highest enrichment,with a range of 110×10-6 to 8200×10-6 and an average of 1661×10-6.It is shown that the oxidized ore is the main carrier and environmental source of cadmium.The leaching test shows that Pb/Zn ore is susceptible to oxidize and readily releases Cd and other harmful elements.These leached elements in the leachate may be deposited rapidly in the order of Zn>Pb>Cd.As for Cd concentration distribution in the water ecosystem of the Bijiang River,15.7 μg/L Cd exists in water,49.3 mg/L in suspended sediment,and 203.7 mg/L in river sediment.The natural weathering of Cd-rich rocks and minerals presents a potential environmental risk for the aquatic ecosystem of the Bijiang catchment.更多还原