西南岩溶区矿山与水污染问题探讨及建议

我国西南石山连片分布的岩溶区,总面积约100万km2,其中裸露岩溶区面积约62万km2,这里虽然年降水量在1000 mm以上,但由于岩溶强烈发育,降水很快转化为地下径流,通过众多岩溶地下河排入位于深切峡谷的大江大河里。该区地形西高东低,西部为云贵高原,东部为低山丘陵区,中部是过渡的斜坡地带。云贵高原处于生态屏障区,是长江和珠江的分水岭。该区矿产资源丰富,如贵州的煤矿、稀有金属、磷矿等;广西的有色金属、锰矿、铝土矿等。采、选矿产生的尾砂及废水,如果处理不当,会污染地表水和地下水,北面影响长江流域,南面影响珠江流域。2008—2010年间,"西南岩溶石山地区重大环境地质问题及对策研究"项目专家组先后几次对岩溶石山区部分矿产开采点引发的水环境污染问题进行考察,认为由于不规范、不合理的矿产开发带来的水环境问题依然比较严重,是影响该地区可持续发展的重大环境地质问题之一。

A Discussion on Mine and Water Pollution Problems in Karst Areas in Southwest China

The continuous distribution of karst in southwest China comes to an area of 1000,000 km2, in which 62×104 km2 is bare karst. Annual precipitation in this area is more than 1000 mm; nevertheless, the rainwater would change into underground water quickly due to intensive development of karst, and would discharge into rivers through numerous karst underground rivers. The topography of this region is high in the west within Yunnan-Guizhou Plateau and low in the east with some low massifs. Yunnan-Guizhou Plateau is located in the ecological barrier, and it is the watershed of the Yangtze River and the Pearl River. This region is rich in mineral resources, such as coal, rare metals and phosphorus in Guizhou Province and non-ferrous metals, manganese and bauxite in Guangxi. The surface water and underground water are liable to be contaminated by the tailings and waste water generated from mining and mineral processing if they are not disposed properly. The Yangtze River and the Pearl River would be polluted consequently. Experts from the project of the Major Environmental Geological Problems and Countermeasures in Karst Mountain Areas in Southwestern China investigated some water pollution cases during 2008 to 2010, and the results show that the water environment problem induced by improper mine exploitation remains a serious problem and would severely affect the sustainable development of this region.