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dc.contributor.supervisorWang, Feiyue (Environment & Geography) Stern, Gary (Environment & Geography)en
dc.contributor.authorCarrie, Jesse D.
dc.date.accessioned2010-04-08T20:04:18Z
dc.date.available2010-04-08T20:04:18Z
dc.date.issued2010-04-08T20:04:18Z
dc.identifier.citationCarrie, J., Sanei, H., Goodarzi, F., Stern, G., Wang, F. (2009) Characterization of organic matter in surface sediments of the Mackenzie River Basin, Canada, International Journal of Coal Geology 77:416-423.en
dc.identifier.citationCarrie, J., Stern, G., Sanei, H., Macdonald, R., Outridge, P., Wang, F. (2010) Increasing contaminant burdens in an Arctic fish, burbot (lota lota), in a warming climate, Environmental Science & Technology 44: 316-322.en
dc.identifier.urihttp://hdl.handle.net/1993/3923
dc.description.abstractMercury (Hg) is a known neurotoxin that is often found in concentrations exceeding safe consumption guidelines in aquatic biota. This is evident in northern Canada, where northerners consume significant amounts of animals such as beluga, seals and burbot. In the Mackenzie River Basin, recent increases in Hg concentration in many of these animals over the past 25 years have been observed. The warming climate, and with it, the changing carbon cycle, are hypothesised in this thesis to play a role in the increases. Within the context of the two major zones (mountainous and peatland), with distinct geomorphology, hydrology and geology, traditional fossil fuel exploration methods (Rock-Eval pyrolysis, organic petrography) have been employed in a novel manner on recent sediments to qualify and quantify the OM and several geochemical analyses have been used to determine the geochemical sources of Hg. The mountainous zone is composed mostly of refractory OM, from forest fire char and heavily reworked OM. It also contains, and fluxes, most of the Hg, which derives from oxidative weathering and erosion of widespread sulfide minerals. However, Hg from this zone is in chemical forms of limited bioavailability. The peatland zone has a greater proportion of labile OM, with higher concentrations of DOC and algal-derived OM. Lake-fed tributaries in this zone contain even higher proportions of labile OM. At one of these sites, the sediment core record shows that Hg has been increasingly associated with labile OM over time, due to increasing primary productivity accelerated by climate change, and is resulting in an increase in scavenged Hg. The temporal trend in algal-bound Hg in the sediment record matches very well with the temporal trend of Hg in burbot sampled from the area, providing one of the first and strongest lines of evidence for the climatic impact on Hg bioaccumulation in Arctic ecosystems.en
dc.format.extent50548251 bytes
dc.format.mimetypeapplication/pdf
dc.language.isoengen_US
dc.rightsinfo:eu-repo/semantics/openAccess
dc.subjectmercuryen
dc.subjectMackenzie Riveren
dc.subjectArcticen
dc.subjectorganic matteren
dc.subjectburboten
dc.subjectclimate changeen
dc.titleOrganic carbon, mercury and climate change: towards a better understanding of biotic contamination in the Canadian Arcticen
dc.typeinfo:eu-repo/semantics/doctoralThesis
dc.typedoctoral thesisen_US
dc.degree.disciplineEnvironment and Geographyen_US
dc.contributor.examiningcommitteePapakyriakou, Tim (Environment & Geography) Macdonald, Robie (Environment & Geography) Halden, Norman (Geological Science) Gobeil, Charles (Institut National de Recherche Scientifique)en
dc.degree.levelDoctor of Philosophy (Ph.D.)en_US
dc.description.noteMay 2010en


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