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dc.contributor.authorPaul, Catherineen
dc.date2008-11-12 16:46:47.174
dc.date.accessioned2008-11-12T21:54:03Z
dc.date.available2008-11-12T21:54:03Z
dc.date.issued2008-11-12T21:54:03Z
dc.identifier.urihttp://hdl.handle.net/1974/1582
dc.descriptionThesis (Master, Biology) -- Queen's University, 2008-11-12 16:46:47.174en
dc.description.abstractPaleoclimatic research in the Canadian Arctic has increased in recent decades; however, there is still much to learn about the nature and extent of past climate change in this vast, environmentally sensitive region. This thesis uses diatom assemblages in dated lake sediment cores as proxy indicators to infer how climate has changed over the Holocene in two very different lakes in the central Canadian Arctic: one located in a poorly-studied geographical region, and another possessing limnological characteristics that are unusual in an Arctic context. Lake TK-2 is located in the low Arctic tundra. Paleolimnological studies from this region are lacking, as most have centered on sites in the High Arctic Archipelago or around Subarctic treeline. Marked changes in the diatom assemblages in TK-2 throughout the Holocene included potential evidence for the 8.2k cooling event, which has not been previously reported from other Canadian Arctic paleolimnological studies. In addition, diatom shifts occurring ~7000 and ~3500 cal yr BP are indicative of mid-Holocene warming and subsequent Neoglacial cooling, respectively, the timings of which agree with those from other studies farther south. Finally, shifts in the diatom assemblages in the upper sediment layers, beginning in the early-to-mid 19th century, are consistent with reduced ice cover, related to recent warming. Stygge Nunatak Pond, a small, closed-basin pond located on a nunatak in the High Arctic on Ellesmere Island, is characterized by unusually high ionic concentrations for an inland Arctic pond. As in TK-2, Stygge’s diatom assemblages changed substantially throughout the Holocene, but especially in the most recent sediments. Diatom shifts near ~10,500 cal yr BP suggest an early onset for the Holocene Thermal Maximum (and for the successive Neoglacial cooling trend) in this region, consistent with previous studies from the High Arctic. Marked diatom assemblage changes occurred in the most recent sediments, and are indicative of climate warming and reduced ice cover, as well as increased ionic concentration due to enhanced evaporative concentration. The dynamic nature of the diatom assemblage changes at the Stygge site suggests that sediments from these rare athalassic ponds represent an especially sensitive archive of Arctic climatic and environmental change.en
dc.format.extent12560032 bytes
dc.format.mimetypeapplication/pdf
dc.language.isoengen
dc.relation.ispartofseriesCanadian thesesen
dc.rightsThis publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.en
dc.subjectpaleolimnologyen
dc.subjectArcticen
dc.subjectdiatomsen
dc.subjectclimate changeen
dc.subjectHoloceneen
dc.subjectsalineen
dc.subject8.2k eventen
dc.titlePaleolimnological assessment of Holocene climatic and environmental change in two lakes located in different regions of the Canadian Arctic tundraen
dc.typethesisen
dc.description.degreeM.Sc.en
dc.contributor.supervisorSmol, John P.en
dc.contributor.departmentBiologyen
dc.degree.grantorQueen's University at Kingstonen


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