HR: 17:00h
AN: PP44A-04 [Abstracts]
TI: Late Holocene Vegetation and Climate Change From the Central and Western Canadian Arctic Inferred From Fossil Pollen Data
AU: * Peros, M
EM: mperos@uottawa.ca
AF: Laboratory for Paleoclimatology and Climatology, University of Ottawa, 60 University
Avenue, Ottawa, ON K1N 6N5, Canada
AU: Gajewski, K
EM: gajewski@uottawa.ca
AF: Laboratory for Paleoclimatology and Climatology, University of Ottawa, 60 University
Avenue, Ottawa, ON K1N 6N5, Canada
AB:
Two sediment cores from the central and western Canadian Arctic were used to document landscape-scale
vegetation and climate changes spanning the last ~2500 years. Both cores were dated by Pb-210 and C-14
techniques. Fossil pollen was enumerated at continuous 1 cm intervals (each centimeter representing a period
of ~70 years), permitting centennial-scale changes to be placed into a long-term context. The pollen percentages
are dominated by Cyperaceae and show relatively uniform values throughout the cores. Quantitative climate
reconstructions, based on the percentage values, are similarly stable. However, the influx of locally- and
regionally-derived pollen grains increases over the last ~150 years, suggesting that higher primary production
and summer temperatures occurred over this time. The pollen results from these cores are consistent with other
high-resolution (~25 year) lake sediment proxy data (BSi and LOI) from the region. Despite this, a comparison of
these data with several Holocene-length pollen records from the same region indicates that the changes that
characterized the last 2000 years were relatively minor compared to those of the early Holocene.
DE: 4950 Paleoecology
DE: 4952 Palynology
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting