中文摘要：

铅锌矿的开采和选冶使含锌和镉等有害物质的尾矿暴露于地表，这些有毒元素通过自然风化淋滤作用进入地表水，进而污染矿区水体，对矿区生态环境破坏性极大。本文通过对贵州都匀牛角塘富镉锌矿区河流、选矿厂排放的污水、坑道水进行采样分析，发现矿区水体呈弱碱性，水体重金属污染并不严重，其中Cd等重金属有毒元素的含量大多没有超过生活用水国家标准和农业灌溉水国家标准。结合已有研究成果，认为碳酸岩地区碱性环境限制了镉等重金属有毒元素的活化迁移，使其就近富集在矿区土壤、植物及河流沉积物中。更重要的是由于碳酸盐岩对矿山酸性排水的中和缓冲作用，降低了矿石的风化淋滤速度，减轻了因铅锌矿开采和选冶活动导致的Zn、Cd等有毒重金属元素对矿区环境的污染，为非碳酸岩地区铅锌矿山环境污染和治理提供了一些借鉴。

英文摘要：

Cadmium, which came mainly from Pb-Zn deposits, is a kind of toxic element. It will be released out with weathering and leaching during exploitation of Pb-Zn ores, It can pollute the environment of mining area. The Niujiaotang Cd-rich zinc deposit, Duyun, Guizhou Province, in which Cd is particularly rich, is hosted in carbonate strata. In this paper, detailed analysis was carried out on water samples from rivers, ore-dressing sewage and sap water. It has been found that water-bodies in the ore areas are alkaline and the pollution of heavy metal elements is not so serious, especially that of Cd, which is lower than that required by Chinese National Standards on drinking water and irrigating water. Based on other data about the ore areas, we think that the carbonates have been limiting the migration and concentration of heavy metal elements, and making them have a tendency of being enriched in soils, plants and river sediments from the water-bodies. What is most important is that supergene weathering and leaching rates are dropped down and the pollution of those toxic heavy metals in the mining district is reduced as a result of neutralization and buffer capacity of the carbonates. All of those provide some way to control the environmental pollution in Pb-Zn mines which are located in non-carbonate areas.