韶关矿产资源开采地区土壤生态系统的微生物生态效应研究

韶关地区大宝山铁多金属矿产资源的开采给环境带来了严重的危害。采选冶产生的废液及固体废弃物堆积的淋滤酸水，携带浸滤出的大量重金属离子排入下游河道，严重影响矿区及酸水流域的生态环境。通过对该铅锌矿区土壤重金属分布、土壤微生物数量与植物重金属积累特征进行采样分析研究，结果表明：铅锌矿区土壤各重金属元素质量分数均高于对照土壤，矿区土壤均受到不同程度的污染；五节芒（Miscanthusfloridulus）植物中的元素质量分数表现为Zn〉Pb〉Cu〉Cd，Zn与土壤元素的相关性最为显著，其次为Pb；与对照土壤相比，矿区土壤微生物总数下降了68．43％-80．32％，各主要生理类群数量均呈下降趋势。矿区土壤生态系统处于不利于有益微生物的繁殖和活动的境地，从而大大削弱了土壤中C、N营养元素循环速率和能量流动。

Studies on soil microbial ecological effect in the exploitation of mineral resources in Shaoguan Guangdong province

Mining activities have caused severe soil environment changes in Dabaoshan Mine, Guangdong,Southem China.The acid mine drainage and heavy metal ions drained directly into the Hengshihe fiver, which contaminated severely the ecological environment along the fiver. This paper reported soil microbial characteristics of Miscanthus floridulus-soil system in heavy metals contaminated soils around Dabaoshan mine tailings, Northern Guangdong. The results indicated that metal element contents of Miscanthus floridulus in sequence were： Zn〉Pb〉Cu〉Cd. There were significant correlations in Zn contents between Miscanthus floridulus and soil in Pb/Zn mine mined tailings region, and the next was in Pb contents. The results indicated that, the total quanlity of major soil microbes declined, of which the minesoils was decreased by 68.43%-80.32% in the top soil（0-20 cm） compared with that of the non-minesoils. The proportion of bacteria and actinomyces in the amount microbes decreased, while that of fungi not obviously changed. The amount of major physiological group including ammonifiers, nitrogenfixing bacteria, celluose decomposing microbes, aerobic nitrogen fixing bacteria and anaerobic nitrogen fixing bacteria all decreased.