CGRG Bibliography of Canadian Geomorphology
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Author : Beierle, B.
Date : 2001.
Title : Holocene climatic changes in the Central Yukon Territory, Canada.
Publication : Canadian Quaternary Association/ Association canadienne pour l'etude du Quaternaire, Annual Meeting 2001. Whitehorse, Yukon Territory, August 20 – 24, 2001.
Issue :
Page(s) :
Abstract
Sediment cores from Chapman Lake, Yukon Territory were analysed to reconstruct paleoenvironmental changes over the past 13,000 years. High resolution organic carbon, macrofossil, grain size, and lithostratigraphic analyses provide evidence for climatic variability in central Yukon and suggest that Holocene climatic changes in this region were similar to those in other regions of North America. High organic carbon levels, as well as abundant charophyte oogonia in the macrofossil record characterized an early Holocene warm interval between 10,000 and 7500 BP. Organic carbon levels began to drop at ca. 7500 BP, declining steadily until ca. 4000 BP, when a major decline in organic carbon content occurred. Charophyte oogonia were replaced by bryophytes as the dominant macrofossil immediately prior to the 4000 BP event, with variable but generally lower organic carbon levels suggesting a cooler and more unstable climate than in the early Holocene. Preliminary evidence suggests conditions began to warm around 1550 BP, with increased organic carbon levels and the reappearance of oogonia in the fossil record. This period of increased productivity ended at 550 BP, with a sharp decline in organic carbon and the return of moss as the primary macrofossil constituent.
Bibliography of Canadian Geomorphology