Mining activities frequently leave a legacy of residues that remain in the area for long periods causing the pollution of surroundings. We studied on a 100 year-old mine, the behaviour of potentially toxic elements (PTEs) and their ecotoxicological impact on activity and diversity of microorganisms. The PTEs contamination assessment allowed the classification of the materials as highly (reference- and contaminated-samples) and very highly polluted (illegal spill of olive mill wastes (OMW), tailings and dumps). OMW presented the lowest enzymatic activities while tailings and dumps had low dehydrogenase and arylsulfatase activities. All the alpha diversity indices studied were negatively impacted in dumps. Tailings had lower Chao1 and PD whole tree values as compared to those of reference-samples. Beta diversity analysis showed similar bacterial community composition for reference- and contaminated-samples, significantly differing from that of tailings and dumps. The relative abundance of Gemmatimonadetes, Bacteroidetes and Verrucomicrobia was lower in OMW, tailings and dumps as compared to reference-samples. Fifty-seven OTUs were selected as responsible of the changes observed between samples. This study highlights that assessing the relationship between physicochemical properties and microbial diversity and activity gives clues about ongoing regulating processes that can be helpful for stakeholders to define an appropriate management strategy.

采矿活动经常会留下大量残留物，这些残留物会长期留在该地区，从而造成周围环境的污染。我们在一个已有100年历史的矿山上进行了研究，研究了潜在有毒元素（PTE）的行为及其对微生物活性和多样性的生态毒理学影响。PTE的污染评估允许将材料分类为高污染（参考样品和受污染样品）和高污染（橄榄厂废物（OMW），尾矿和垃圾场的非法溢出）。OMW的酶活性最低，而尾矿和垃圾场的脱氢酶和芳基硫酸酯酶的活性较低。研究的所有alpha多样性指数均对垃圾场产生负面影响。与参考样品相比，尾矿的Chao1和PD全树值更低。Beta多样性分析显示，参考样品和受污染样品的细菌群落组成相似，与尾矿和垃圾场明显不同。与参考样品相比，OMW，尾矿和垃圾场中的芽孢杆菌，拟杆菌和Verrucomicrobia的相对丰度较低。选择了57个OTU作为样本之间观察到的变化的原因。这项研究强调，评估理化特性与微生物多样性和活性之间的关系可提供有关正在进行的调节过程的线索，这些过程可有助于利益相关者确定适当的管理策略。与参考样品相比，拟杆菌和Verrucomicrobia在OMW，尾矿和废物堆中较低。选择了57个OTU作为样本之间观察到的变化的原因。这项研究强调，评估理化特性与微生物多样性和活性之间的关系可提供有关正在进行的调节过程的线索，这些过程可有助于利益相关者确定适当的管理策略。与参考样品相比，拟杆菌和Verrucomicrobia在OMW，尾矿和垃圾场中较低。选择了57个OTU作为样本之间观察到的变化的原因。这项研究强调，评估理化特性与微生物多样性和活性之间的关系可提供有关正在进行的调节过程的线索，这些过程可有助于利益相关者确定适当的管理策略。