Establishing tailings associated sulfur biogeochemical cycling across the resource extractive industries

尾矿环境是地球上发展最快、研究最少的生物地球化学景观之一。加拿大采矿业每年抽取大约10亿立方米的淡水，大约相当于我们每年可再生水供应量的一半，这些水主要返回到接收环境。开采活动对水的改变会对环境造成严重威胁。在这些开采过程中，加拿大的采矿活动每天产生大约200万吨废石（覆盖层）和尾矿（经过处理的、有毒的、高度改变的水泥浆、岩石颗粒和化学添加剂）。由于尾矿可能对环境和人类健康造成风险，它们通常被储存在尾矿池中，导致大量废水需要处理。这些尾矿库产生的废水如果处理不当，有可能对下游的接收环境造成重大影响。这些尾矿库仍然是一个微生物黑箱，可能会产生不可预测的影响。特别是金属采矿（含硫化物丰富的矿石）和油砂尾矿，已知是富硫的；并且含有高度变化的、不同浓度的碳、氮和铁化合物，这将使硫和其他生物地球化学循环之间存在广泛的可能的相互联系。在全球范围内，许多现有的尾矿环境仍然存在产生有害硫相关影响的风险，如酸性矿山排水和高浓度硫化氢气体，突出表明有必要开展新的研究工作，阐明在这些背景下控制S循环的生物地球化学转化，以更好地预防此类影响。此外，随着这些环境在世界范围内的不断增加，它们将对全球硫生物地球化学循环做出越来越重要的贡献。拟议的创新研究计划的目标是建立对整个采掘资源采矿部门尾矿中硫生物地球化学循环的全面了解，从中亟需新的解决方案来实现更可持续的管理，并可以开发更全面的全球硫生物地球化学模型。这一长期研究计划的目标将通过实验研究活动来实现，这些实验研究活动将系统地建立一个新的知识平台，该平台基于对所涉及的不同微生物的机制理解，催化途径和相关控制，以及从一套全面的矿山尾矿样品中对硫氧化还原循环的不同电子供体和受体的影响。10名HQP将接受对加拿大至关重要的尖端环境生物地球化学研究方面的培训。

Mine tailings environments are one of the fastest growing and least studied biogeochemical landscapes on the planet. Every year the Canadian mining industry withdraws approximately one billion cubic meters of freshwater, approximately equivalent to ½ of our annual, renewable water supplies, which is predominantly returned to receiving environments.The alteration of this water through operational extraction activities can pose significant environmental threats. In those extractive processes, Canadian mining activities generate approximately 2 million tons of waste rock (overburden) and tailings (post-processed, toxic, aqueous slurries of highly altered, rock particles and chemical additives) daily. Because of the environmental and human health risks tailings can pose, they are typically stored on site in tailings ponds, resulting in large amounts of wastewater requiring treatment. The wastewater generated from these tailings impoundments has the potential to cause significant impacts to the downstream receiving environments if not properly treated. These tailings impoundments remain a microbial black box from which unpredictable impacts can emerge. In particular both metal mining (sulfide rich ores) and oil sands tailings, are known to be sulfur rich; and contain highly altered, varying concentrations of carbon, nitrogen and iron compounds that would enable a broad array of possible interconnections between sulfur and other biogeochemical cycles. At the global scale many existing tailings environments remain at risk of developing deleterious sulfur related impacts such as acid mine drainage, and high levels of hydrogen sulfide gas, highlighting that novel research efforts are necessary to elucidate the biogeochemical transformations governing S cycling in these contexts to better prevent such impacts. Further, as these contexts continue to increase worldwide, they will be an increasingly important contribution to the global sulfur biogeochemical cycle. The goal of the proposed innovative research program is to establish a comprehensive understanding of sulfur biogeochemical cycling occurring within tailings from across the extractive resources mining sector, from which vitally need new solutions for more sustainable management and a more comprehensive global sulfur biogeochemical model can be developed. This long-term research program goal will be met through experimental research activities that will systematically build a new knowledge platform based on the generation of mechanistic understanding of the different microbes involved, the catalyzed pathways and associated controls as well as the implications of varying electron donors and acceptors for sulfur redox cycling from a comprehensive suite of mine tailings samples. Ten HQP will receive training in cutting edge environmental biogeochemical research of critical Canadian importance.