CGRG Bibliography of Canadian Geomorphology
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Author : Antoniades, D.; Douglas, M.S.V.; and Smol, J.P.
Date : 2001.
Title : Recent environmental change inferred from diatom records at Isachsen, Ellef Ringnes Island, Canadian High Arctic.
Publication : Canadian Quaternary Association/ Association canadienne pour l'etude du Quaternaire, Annual Meeting 2001. Whitehorse, Yukon Territory, August 20 – 24, 2001.
Issue :
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Abstract
Although the Canadian High Arctic is recognized as an important indicator of global environmental change, little or no historical climate information exists across this large region. Paleolimnological proxy records using bioindicators such as diatoms can potentially provide these missing data sets. Isachsen (78°47'N, 103°32'W) is located on the west coast of Ellef Ringnes Island in the Canadian Arctic Archipelago. It is subject to perhaps the most extreme climate in Canada, with annual averages of -19.1°C, and only 102 mm precipitation. Sediment cores were extracted from two shallow sites near Isachsen in July of 1996. Sites I-F and I-O (unofficial names) showed large differences in water chemistry (e.g., I-F: pH = 5.9, conductivity = 158mS; I-O: pH = 6.9, cond. = 17mS), which resulted largely from differences in local bedrock and topography. The diatom communities reflected these differences, showing little overlap between the two sites. However, recent stratigraphic changes occurred in both records. A stable diatom flora dominated by relatively few species existed throughout the lower portions of each core. Within a few centimeters of the sediment surface, both sites showed trends towards new dominant taxa and greater species diversity. This shift occurred at 2.5 cm depth in core I-O, and 4 cm in core I-F. A diatom calibration set for the Isachsen region is currently being constructed in an effort to determine and quantify the cause of these changes.
Bibliography of Canadian Geomorphology