GFZ German Research Centre for Geosciences, Section 4.3 Organic Geochemistry, Telegrafenberg, 14473 Potsdam, Germany.
University of Potsdam, Institute of Earth and Environmental Science, Geomicrobiology Group, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany.
Sci Total Environ. 2014 Nov 15;499:297-310. doi: 10.1016/j.scitotenv.2014.08.020. Epub 2014 Sep 6.
Recultivation of disturbed oil sand mining areas is an issue of increasing importance. Nevertheless only little is known about the fate of organic matter, cell abundances and microbial community structures during oil sand processing, tailings management and initial soil development on reclamation sites. Thus the focus of this work is on biogeochemical changes of mined oil sands through the entire process chain until its use as substratum for newly developing soils on reclamation sites. Therefore, oil sand, mature fine tailings (MFTs) from tailings ponds and drying cells and tailings sand covered with peat-mineral mix (PMM) as part of land reclamation were analyzed. The sample set was selected to address the question whether changes in the above-mentioned biogeochemical parameters can be related to oil sand processing or biological processes and how these changes influence microbial activities and soil development. GC-MS analyses of oil-derived biomarkers reveal that these compounds remain unaffected by oil sand processing and biological activity. In contrast, changes in polycyclic aromatic hydrocarbon (PAH) abundance and pattern can be observed along the process chain. Especially naphthalenes, phenanthrenes and chrysenes are altered or absent on reclamation sites. Furthermore, root-bearing horizons on reclamation sites exhibit cell abundances at least ten times higher (10(8) to 10(9) cells g(-1)) than in oil sand and MFT samples (10(7) cells g(-1)) and show a higher diversity in their microbial community structure. Nitrate in the pore water and roots derived from the PMM seem to be the most important stimulants for microbial growth. The combined data show that the observed compositional changes are mostly related to biological activity and the addition of exogenous organic components (PMM), whereas oil extraction, tailings dewatering and compaction do not have significant influences on the evaluated compounds. Microbial community composition remains relatively stable through the entire process chain.
扰动油砂矿区的复垦是一个日益重要的问题。然而，人们对油砂加工、尾矿处理和复垦场地初始土壤发育过程中有机质、细胞丰度和微生物群落结构的命运知之甚少。因此，本工作的重点是通过整个过程链研究开采油砂的生物地球化学变化，直到将其用作复垦场地新开发土壤的基质。因此，分析了油砂、尾矿池中的成熟细尾矿（MFT）以及干燥的细胞和覆盖有泥炭-矿物混合体（PMM）的尾矿砂，作为土地复垦的一部分。选择样本集以解决以下问题：上述生物地球化学参数的变化是否与油砂加工或生物过程有关，以及这些变化如何影响微生物活性和土壤发育。油衍生生物标志物的 GC-MS 分析表明，这些化合物不受油砂加工和生物活性的影响。相比之下，可以沿过程链观察到多环芳烃（PAH）丰度和模式的变化。特别是萘、菲和芘在复垦场地上发生了改变或缺失。此外，复垦场地上的含根层的细胞丰度至少比油砂和 MFT 样品高十倍（10^8 到 10^9 个细胞/g），并且其微生物群落结构的多样性更高。孔隙水中的硝酸盐和源自 PMM 的根似乎是微生物生长的最重要刺激物。综合数据表明，观察到的组成变化主要与生物活性和外加有机成分（PMM）有关，而油提取、尾矿脱水和压实对评估化合物没有显著影响。微生物群落组成在整个过程链中保持相对稳定。
