CGRG Bibliography of Canadian Geomorphology
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Author : Bunbury, J.; and Gajewski, K.
Date : 2007.
Title : Aquatic and terrestrial ecosystem response to Holocene climatic change inferred from lake sediments, southwest Yukon Territory.
Publication : CANQUA Ottawa 2007. Canadian Quaternary Association Conference, June 4-8, 2007. Carleton University, Ottawa, Ontario, Canada.
Issue :
Page(s) :
Abstract
A sediment core from Upper Fly Lake (61.04°N, 138.09°W, 1326 m.a.s.l.) in the southwest Yukon reveals synchronous changes in the aquatic animal community and the terrestrial vegetation community. The pollen spectra indicate a shrub tundra environment dominated by Salix, Artemisia, Cyperaceae and Gramineae in the earliest part of the Holocene, followed by shrub tundra dominated by Betula pollen. During this period, chironomid assemblages were dominated by Psectrocladius and Sergentia, and later Tanytarsina. In the early to mid-Holocene, Picea glauca and Alnus crispa migrated into the region, Tanytarsina became less abundant, and Chironomus and Sergentia dominated the chironomid assemblages. In the mid-Holocene, Alnus crispa reached maximum abundance and Cricotopus/Orthocladius types appeared in the core. These, and Sergentia were abundant until about 120 cal yrs BP, when Chironomus and Corynocera oliveri-type dominated. Chironomid concentrations reached maximum values just after deglaciation, declined in the mid-Holocene, and were variable in the late Holocene. Sediment organic content increased steadily in the early Holocene, whereas sediment carbonate content was high but variable. These sediment parameters were less variable in the late Holocene during the time that Picea glauca pollen percentages were high.
Bibliography of Canadian Geomorphology