Biostimulation for Enhanced Bioremediation of Crude Oil and Diesel Fuel by Marine Sediment Communities of Canada’s Subarctic: A Microcosm-Simulated Oil Spill Study

Murphy, Sean Michael Colin

Biostimulation for Enhanced Bioremediation of Crude Oil and Diesel Fuel by Marine Sediment Communities of Canada’s Subarctic: A Microcosm-Simulated Oil Spill Study

dc.contributor.advisor	Hubert, Casey R. J.
dc.contributor.author	Murphy, Sean Michael Colin
dc.contributor.committeemember	Gieg, Lisa M.
dc.contributor.committeemember	Vamosi, Steven M.
dc.date	2020-06
dc.date.accessioned	2020-01-24T17:31:27Z
dc.date.available	2020-01-24T17:31:27Z
dc.date.issued	2020-01-23
dc.description.abstract	Increases in shipping traffic, future mining, and oil and gas developments represent significant oil spill risks in Canada’s subarctic marine environment. The impact of oil on marine ecosystems and the traditional activities of local indigenous peoples are of major concern. To understand the response of local microbial communities to oil contamination and nutrient biostimulation, microcosm-simulated oil spills contaminated with diesel fuel or crude oil and incubated at 4°C were constructed using marine sediments from Hudson Bay and the Labrador Sea. Changes in microbial community structure, diversity, and composition were monitored by DNA extraction, the amplification of 16S rRNA genes, followed by sequencing and taxonomic classifications. Additionally, hydrocarbon degradation in response to bioremediation was monitored by changes in gas compositions with GC, and through hydrocarbon extractions and GC-MS analysis. Results suggested that petroleum hydrocarbons decreased observed microbial diversity and led to dominance by Gammaproteobacteria in both sediments, where many hydrocarbonoclastic bacteria (HCB) increased heavily in abundance at both sites, including Cycloclasticus, Marinobacter, Oleispira, Paraperlucidibaca, Pseudomonas, Thalassolituus, and Zhongshania. The same OTUs were found to increase in abundance in both high and low nutrient treatments, but biostimulation was found to increase initial rates of biodegradation by accelerating the succession and dominance of these HCB. Increase in the relative abundance of Cycloclasticus was noted as signifying succession in response to hydrocarbon degradation and biostimulation. The Labrador Sea sediment community was found to be more responsive to oil spills and biostimulation mitigation strategies, which could be tied to historical exposures of the community to natural oil seepages in the region. Porticoccus and Oleispira are suggested as robust bioindicators for cold seawater environments contaminated by diesel or crude oil, respectively. A comparison of three PCR primer pairs for HCB detection found 341F/806R was the preferred choice for detecting HCB taxa and assessing environmental baselines in areas at risk of oil spills. Microbial biodiversity baselines and in situ rates of microbial degradation should be included in future environment assessments by industry. Overall, this study provided a first account of key crude oil- and diesel-degrading bacteria among marine sediments in this subarctic region.	en_US
dc.identifier.citation	Murphy, S. M. C. (2020). Biostimulation for Enhanced Bioremediation of Crude Oil and Diesel Fuel by Marine Sediment Communities of Canada’s Subarctic: A Microcosm-Simulated Oil Spill Study (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.	en_US
dc.identifier.doi	http://dx.doi.org/10.11575/PRISM/37500
dc.identifier.uri	http://hdl.handle.net/1880/111552
dc.language.iso	eng	en_US
dc.publisher.faculty	Science	en_US
dc.publisher.institution	University of Calgary	en
dc.rights	University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.	en_US
dc.subject	Bioremediation	en_US
dc.subject	Biostimulation	en_US
dc.subject	Hydrocarbonoclastic Bacteria	en_US
dc.subject	Oil Spill	en_US
dc.subject	Labrador Sea	en_US
dc.subject	Hudson Bay	en_US
dc.subject	Subarctic	en_US
dc.subject	Hydrocarbon Degradation	en_US
dc.subject	16S rRNA Amplicon Sequencing	en_US
dc.subject.classification	Microbiology	en_US
dc.subject.classification	Engineering--Environmental	en_US
dc.title	Biostimulation for Enhanced Bioremediation of Crude Oil and Diesel Fuel by Marine Sediment Communities of Canada’s Subarctic: A Microcosm-Simulated Oil Spill Study	en_US
dc.type	doctoral thesis	en_US
thesis.degree.discipline	Biological Sciences	en_US
thesis.degree.grantor	University of Calgary	en_US
thesis.degree.name	Master of Science (MSc)	en_US
ucalgary.item.requestcopy	true	en_US