Interactive effects of insects, fire and climate on fuel loads and fire behavior in mixed conifer forest
This project is aimed at elucidating the effect of interactions of fire, insect outbreaks, windthrow, and climate on fuel and fire behavior using simulation modeling fit to historical climate and disturbance histories developed from tree-ring reconstructions at 22 sites in mixed-conifer forests across a climate gradient from northeastern Oregon to western Montana. We will test three hypotheses: H1: Climate directly influences fuel dynamics through rates of establishment and mortality. H2: Climate, such as prolonged drought, and disturbance history predispose stands to subsequent disturbance. H3: The strength and type of disturbance interactions vary among climatic regions. While fire and insect outbreak histories have already been reconstructed by us and others in this region, unfortunately they rarely have been reconstructed at the same site. We will take advantage of prior work by reconstructing fire histories at sites with existing insect histories and vice versa as well as sampling both at a few new sites. We will use a mechanistic, process-driven stand dynamics model (FIRE-BGC) to examine how interactions of historical climate and disturbances influenced fuel profiles through time. We will use a physics-based dynamic fire model (Wildland Fire Dynamics Simulator or WFDS) to examine how these fuel profiles affected potential fire behavior through time.  Existing fire history and insect history sampling sites, showing sites for additional sampling and 4 proposed new sites. 3 additional new sites (not shown) will be located on contrasting aspects near existing sites. Base maps from Williams and Birdsey (2003). Only forested areas are shown. |
||||||||
