Genetic characterization of petroleum-degrading microorganisms in contaminated fractured bedrock systems undergoing phytoremediation

据估计，加拿大有30,000个棕地，因此棕地重建已被确定为振兴内城地区和防止绿地开发的重要因素。然而，由于场地的特定特征或靠近居民区和其他交通繁忙地区，传统的补救技术可能不可行。因此，新的修复方法，如植物修复，或通过涉及植物及其相关微生物群落组合的生物过程降解有机污染物，可能是合适的。BP加拿大能源集团ULC （BP加拿大）在一个历史生产设施（“现场”）保留环境责任。大约5年前，该场地种植了杂交杨树（Populus x Canadensis），作为地下水中甲苯浓度升高的补救策略。BP加拿大公司致力于优化现有植物修复系统的有效性，详细描述导致甲苯降解或衰减的过程，并在可能的情况下利用与土壤、基岩、地下水和植物本身相关的天然甲苯降解微生物来增强这些过程。发展替代性就地生物修复技术的必要第一步是确定污染对现有微生物群落的影响，并评估这些群落是否有能力降解甲苯。Dunfield实验室将使用分子技术来评估污染物对微生物群落的影响，以及基岩、土壤和地下水样本中甲苯降解微生物的存在/丰度。它们将针对与甲苯降解相关的群体，包括好氧（甲苯双加氧酶）和厌氧（苯琥珀酸合酶）细菌甲苯降解途径。增加我们对微生物群落动态的理解可能对目前正在进行的改进现场原位修复策略的努力是无价的。这些知识最终将有助于制定策略来修复其他棕地系统。

There are an estimated 30,000 brownfield sites across Canada and brownfield redevelopment has thus been identified as an important factor in revitalizing inner city areas and preventing development of greenfield lands. However, conventional remediation technologies may not be feasible due to site-specific characteristics or proximity to residential and other high-traffic areas. As such, new remediation methods, such as phytoremediation, or the degradation of organic contaminants via biological processes involving a combination of a plant and its associated microbial community, may be appropriate. BP Canada Energy Group ULC (BP Canada) retains environmental liability at a historical manufacturing facility ("the Site"). The Site was planted with hybrid poplar (Populus x Canadensis) approximately 5 years ago as a remedial strategy for elevated concentrations of toluene in groundwater. BP Canada is committed to optimizing the effectiveness of the existing phytoremediation system through detailed characterization of the processes contributing to toluene degradation or attenuation and augmenting those processes where possible using native toluene-degrading microorganisms associated with soil, bedrock, groundwater and the plants themselves. A necessary first step to developing alternative in situ bioremediation techniques is to determine the effects of contamination on existing microbial communities, and assess whether these communities are capable of degrading toluene. The Dunfield lab will use molecular techniques to assess contaminant effects on microbial communities and presence/abundance of toluene-degrading microbes in bedrock, soil and groundwater samples. They will target groups associated with toluene degradation including both aerobic (toluene dioxygenase) and anaerobic (benzylsuccinate synthase) bacterial toluene-degradation pathways. Increasing our understanding of microbial community dynamics may be invaluable to current efforts that are underway to improve in situ remediation strategies on the Site. This knowledge will ultimately contribute to the development of strategies to remediate other brownfield systems.