Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network

  Advanced Search  

Fire history of white and Lutz spruce forests on the Kenai Peninsula, Alaska, over the last two

Summary: Fire history of white and Lutz spruce forests on
the Kenai Peninsula, Alaska, over the last two
millennia as determined from soil charcoal
Edward E. Berg a,*, R. Scott Anderson b
U.S. Fish and Wildlife Service, Kenai National Wildlife Refuge, P.O. Box 2139, Soldotna, AK 99669, USA
Center for Environmental Science & Education, & Quaternary Sciences Program,
Northern Arizona University, Box 5694, Flagstaff, AZ 86011, USA
The presence of over 429,000 ha of forest with spruce (Picea spp.) recently killed by spruce beetles (Dendroctonus rufipennis) on the Kenai
Peninsula has raised the specter of catastrophic wildfire. Dendrochronological evidence indicated that spruce beetle outbreaks occurred on average
every 50 years in these forests. We used 121 radiocarbon-dated soil charcoal samples collected from throw mounds of recently blown over trees to
reconstruct the regional fire history for the last ca. 2500 years and found no relation between fire activity and past spruce beetle outbreaks. Soil
charcoal data suggest that upland forests of white (Picea glauca) and Lutz (Picea x lutzii) spruce have not on average burned for 600 years (time-
since-fire range 90 to $1500 years, at 22 sites) and that the mean fire interval was 400600 years. It would thus appear that 10 or more spruce beetle
outbreaks can occur for every cycle of fire in these forests. We caution, however, that a trend of warmer summers coupled with an increasing human
population and associated sources of ignitions may create a greater fire risk in all fuel types than was present during the time period covered by our
study. We suggest that forest management focus on creating fuel breaks between valued human infrastructure and all types of forest fuels, both
green and dead.


Source: Anderson, R. Scott - Quaternary Sciences Program, Northern Arizona University


Collections: Geosciences; Environmental Sciences and Ecology