CSIRO Publishing Books Journals About Us Shopping Cart You are here: Journals > International Journal of Wildland Fire   
International Journal of Wildland Fire
  Published on behalf of the International Association of Wildland Fire
 
Search
 
 
  Advanced Search
   

Journal Home
About the Journal
Editorial Board
Contacts
Content
Online Early
Current Issue
Just Accepted
All Issues
Special Issues
Sample Issue
For Authors
General Information
Notice to Authors
Submit Article
For Referees
General Information
Review Article
Annual Referee Index
For Subscribers
Subscription Prices
Customer Service
Print Publication Dates

 Early Alert
Subscribe to our email Early Alert or RSS feeds for the latest journal papers.

 Connect with us
facebook   youtube

Training

Publication Workshops


 

Article << Previous     |     Next >>   Contents Vol 17(1)

Holocene vegetation and fire regimes in subalpine and mixed conifer forests, southern Rocky Mountains, USA

R. S. Anderson A F, C. D. Allen B, J. L. Toney C D, R. B. Jass C E, A. N. Bair C

A Center for Environmental Sciences and Quaternary Sciences Program, Northern Arizona University, Flagstaff, AZ 86011, USA.
B US Geological Survey, Jemez Mountains Field Station, Los Alamos, NM 87544, USA.
C Quaternary Sciences Program, Northern Arizona University, Flagstaff, AZ 86011, USA.
D Present address: Department of Geological Sciences, Brown University, 324 Brook Street, Providence, RI 02912, USA.
E Present address: 4014A Lewis Lane, Austin, TX 78756, USA.
F Corresponding author. Email: scott.anderson@nau.edu
 
PDF (1.1 MB) $25
 Export Citation
 Print
  


Abstract

Our understanding of the present forest structure of western North America hinges on our ability to determine antecedent forest conditions. Sedimentary records from lakes and bogs in the southern Rocky Mountains of Colorado and New Mexico provide information on the relationships between climate and vegetation change, and fire history since deglaciation. We present a new pollen record from Hunters Lake (Colorado) as an example of a high-elevation vegetation history from the southern Rockies. We then present a series of six sedimentary records from ~2600 to 3500-m elevation, including sites presently at the alpine–subalpine boundary, within the Picea engelmanniiAbies lasiocarpa forest and within the mixed conifer forest, to determine the history of fire in high-elevation forests there. High Artemisia and low but increasing percentages of Picea and Pinus suggest vegetation prior to 13 500 calendar years before present (cal yr BP) was tundra or steppe, with open spruce woodland to ~11 900 cal yr BP. Subalpine forest (Picea engelmannii, Abies lasiocarpa) existed around the lake for the remainder of the Holocene. At lower elevations, Pinus ponderosa and/or contorta expanded 11 900 to 10 200 cal yr BP; mixed conifer forest expanded ~8600 to 4700 cal yr BP; and Pinus edulis expanded after ~4700 cal yr BP. Sediments from lake sites near the alpine–subalpine transition contained five times less charcoal than those entirely within subalpine forests, and 40 times less than bog sites within mixed conifer forest. Higher fire episode frequencies occurred between ~12 000 and 9000 cal yr BP (associated with the initiation or expansion of south-west monsoon and abundant lightning, and significant biomass during vegetation turnover) and at ~2000–1000 cal yr BP (related to periodic droughts during the long-term trend towards wetter conditions and greater biomass). Fire episode frequencies for subalpine–alpine transition and subalpine sites were on average 5 to 10 fire events/1000 years over the Holocene, corresponding to one fire event every ~100 to 200 years. (5) Our Holocene-length sedimentary charcoal records provide additional evidence for the anomalous nature of the 20th-century fire regime, where fires were largely suppressed as a national policy.

Keywords: fire history, paleoecology, pollen analysis.


   
Subscriber Login
Username:
Password:  

    


 
Top  Email this page
 
Legal & Privacy | Contact Us | Help

CSIRO

© CSIRO 1996-2012