Fortin D, Roy M, Rioux J, Thibault P
Department of Earth Sciences, University of Ottawa, 140 Louis Pasteur, K1N 6N5, Ottawa, Ont., Canada
FEMS Microbiol Ecol. 2000 Sep 1;33(3):197-208. doi: 10.1111/j.1574-6941.2000.tb00742.x.
Sulfate-reducing bacteria (SRB) have been observed in mining environments, but their presence has not been linked to specific physico-chemical and mineralogical factors. The present study was undertaken to assess the presence of SRB in several Au and Cu-Zn mine tailings located near Timmins, Ont., Canada, and determine the factors responsible for their presence. Vegetated and non-vegetated mine tailings were sampled for SRB enumeration, pH, Eh, water content, total carbon content and sequential chemical extraction. Results first showed that SRB populations were present at all sites and that their distribution varied with depth. Populations were recovered from neutral pH and slightly anoxic tailings and from highly acidic (pH 2) and oxic tailings. The total carbon content of the tailings was generally low and not related to the presence of vegetation. In addition, the carbon content did not affect SRB population distribution and appeared to be more related to the type of tailings, i.e., oxidized and acidic Cu-Zn tailings contained on average more carbon than Au tailings. Results also indicated that the water content of the tailings varied greatly with depth and was not related to the presence of SRB populations. The sequential chemical extraction showed that the pyrite content of the tailings was lower in Au tailings than in Cu-Zn tailings, and that some oxidized Cu-Zn sites were depleted in pyrite due to microbial and chemical oxidation. Our results indicate that SRB could be cultured from a variety of sites and sample types, and that factors such as pH, Eh, water content and carbon content at the collection sites did not exert control on their presence.
在采矿环境中已观察到硫酸盐还原菌（SRB），但其存在尚未与特定的物理化学和矿物学因素相关联。本研究旨在评估加拿大安大略省蒂明斯附近的几个金和铜锌矿尾矿中SRB的存在情况，并确定其存在的影响因素。对有植被和无植被的矿尾矿进行采样，以测定SRB数量、pH值、氧化还原电位（Eh）、含水量、总碳含量以及连续化学萃取情况。结果首先表明，所有采样点均存在SRB菌群，且其分布随深度而变化。在中性pH值和微缺氧的尾矿中以及高酸性（pH 2）和有氧的尾矿中均检测到了SRB菌群。尾矿的总碳含量普遍较低，且与植被的存在无关。此外，碳含量并未影响SRB菌群的分布，似乎与尾矿类型更相关，即氧化的酸性铜锌尾矿平均含碳量比金尾矿更多。结果还表明，尾矿的含水量随深度变化很大，且与SRB菌群的存在无关。连续化学萃取表明，金尾矿中尾矿的黄铁矿含量低于铜锌尾矿，并且一些氧化的铜锌矿点由于微生物和化学氧化作用，黄铁矿已被耗尽。我们的结果表明，可以从各种采样点和样品类型中培养出SRB，并且采样点的pH值、Eh、含水量和碳含量等因素对其存在没有控制作用。
