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Using fire regimes to delineate zones in a high-resolution lake sediment record from the western United States

Published online by Cambridge University Press:  20 January 2017

Jesse L. Morris ,
Andrea Brunelle ,
R. Justin DeRose ,
Heikki Seppä ,
Mitchell J. Power ,
Vachel Carter  and
Ryan Bares
Jesse L. Morris*
Affiliation:
Department of Geosciences and Geography, University of Helsinki, 00014 Helsinki, Finland
Andrea Brunelle
Affiliation:
Department of Geography, University of Utah, Salt Lake City, UT 84112, USA
R. Justin DeRose
Affiliation:
USDA Forest Service, Forest Inventory Analysis, Rocky Mountain Research Station, Ogden, UT 84401, USA
Heikki Seppä
Affiliation:
Department of Geosciences and Geography, University of Helsinki, 00014 Helsinki, Finland
Mitchell J. Power
Affiliation:
Department of Geography, University of Utah, Salt Lake City, UT 84112, USA Utah Museum of Natural History, Garrett Herbarium, University of Utah, Salt Lake City, UT 84112, USA
Vachel Carter
Affiliation:
Department of Geography, University of Utah, Salt Lake City, UT 84112, USA
Ryan Bares
Affiliation:
Department of Geography, University of Utah, Salt Lake City, UT 84112, USA
*
*Corresponding author. E-mail address:[email protected] (J.L. Morris).
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Abstract

Paleoenvironmental reconstructions are important for understanding the influence of long-term climate variability on ecosystems and landscape disturbance dynamics. In this paper we explore the linkages among past climate, vegetation, and fire regimes using a high-resolution pollen and charcoal reconstruction from Morris Pond located on the Markagunt Plateau in southwestern Utah, USA. A regime shift detection algorithm was applied to background charcoal accumulation to define where statistically significant shifts in fire regimes occurred. The early Holocene was characterized by greater amounts of summer precipitation and less winter precipitation than modern. Ample forest fuel and warm summer temperatures allowed for large fires to occur. The middle Holocene was a transitional period between vegetation conditions and fire disturbance. The late Holocene climate is characterized as cool and wet reflecting an increase in snow cover, which reduced opportunities for fire despite increased availability of fuels. Similarities between modern forest fuel availability and those of the early Holocene suggest that warmer summers projected for the 21st century may yield substantial increases in the recurrence and ecological impacts of fire when compared to the fire regime of the last millennium.

Keywords

CharcoalFire regimeFire seasonForest disturbanceLake sedimentsPollenPaleoecologyRegime shiftSpruce-fir forestWildfire
Type
Research Article
Information
Quaternary Research , Volume 79 , Issue 1 , January 2013 , pp. 24 - 36
Copyright
University of Washington

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