VanMensel Danielle, Chaganti Subba Rao, Boudens Ryan, Reid Thomas, Ciborowski Jan, Weisener Christopher
Great Lakes Institute of Environmental Science, University of Windsor, 401 Sunset Avenue, Windsor, Ontario, N9B 3P4, Canada.
Department of Biology, University of Windsor, Windsor, Ontario, Canada.
Microb Ecol. 2017 Aug;74(2):362-372. doi: 10.1007/s00248-017-0953-7. Epub 2017 Mar 1.
Open-pit mining of the Athabasca oil sands has generated large volumes of waste termed fluid fine tailings (FFT), stored in tailings ponds. Accumulation of toxic organic substances in the tailings ponds is one of the biggest concerns. Gamma irradiation (GI) treatment could accelerate the biodegradation of toxic organic substances. Hence, this research investigates the response of the microbial consortia in GI-treated FFT materials with an emphasis on changes in diversity and organism-related stimuli. FFT materials from aged and fresh ponds were used in the study under aerobic and anaerobic conditions. Variations in the microbial diversity in GI-treated FFT materials were monitored for 52 weeks and significant stimuli (p < 0.05) were observed. Chemoorganotrophic organisms dominated in fresh and aged ponds and showed increased relative abundance resulting from GI treatment. GI-treated anaerobic FFT reported stimulus of organisms with biodegradation potential (e.g., Pseudomonas, Enterobacter) and methylotrophic capabilities (e.g., Syntrophus, Smithella). In comparison, GI-treated anaerobic FFT stimulated Desulfuromonas as the principle genus at 52 weeks. Under aerobic conditions, GI-treated FFT showed stimulation of organisms capable of sulfur and iron cycling (e.g., Geobacter). However, GI-treated aerobic FFT showed no stimulus at 52 weeks. This research provides an enhanced understanding of oil sands tailings biogeochemistry and the impacts of GI treatment on microorganisms as an effect for targeting toxic organics. The outcomes of this study highlight the potential for this approach to accelerate stabilization and reclamation end points. Graphical Abstract.
阿萨巴斯卡油砂的露天开采产生了大量被称为流体细尾矿（FFT）的废弃物，这些废弃物被储存在尾矿池中。尾矿池中有毒有机物质的积累是最令人担忧的问题之一。伽马辐射（GI）处理可以加速有毒有机物质的生物降解。因此，本研究调查了经GI处理的FFT材料中微生物群落的反应，重点关注多样性变化和与生物体相关的刺激。在有氧和厌氧条件下，使用来自老化池塘和新鲜池塘的FFT材料进行研究。对经GI处理的FFT材料中的微生物多样性变化进行了52周的监测，并观察到了显著的刺激（p<0.05）。在新鲜和老化池塘中，化能有机营养生物占主导地位，并且由于GI处理，其相对丰度有所增加。经GI处理的厌氧FFT报告了具有生物降解潜力的生物体（如假单胞菌、肠杆菌）和甲基营养能力的生物体（如互营菌属、史密斯氏菌属）受到刺激。相比之下，经GI处理的厌氧FFT在52周时刺激脱硫单胞菌成为主要属。在有氧条件下，经GI处理的FFT显示出对能够进行硫和铁循环的生物体（如地杆菌）的刺激。然而，经GI处理的有氧FFT在52周时未显示出刺激。本研究增进了对油砂尾矿生物地球化学以及GI处理对作为针对有毒有机物的一种效应的微生物的影响的理解。本研究的结果突出了这种方法加速稳定化和复垦终点的潜力。图形摘要。
