Modeling wildfire regimes in forest landscapes: abstracting a complex reality

Fire is a natural disturbance that is nearly ubiquitous in terrestrial ecosystems. The capacity to burn exists virtually wherever vegetation grows. In some forested landscapes, fi re is a principal driver of rapid ecosystem change, resetting succession ( McKenzie et al. 1996a ) and changing wildlife habitat (Cushman et al. 2011 ), hydrology ( Feikema et al. 2013 ), element cycles ( Smithwick 2011 ), and even landforms (Pierce et al. 2004 ). In boreal forests, for example, recurring wildfi res are the main cause of compositional and spatial patterns ( Wein and MacLean 1983 ), where a fi re-induced “shifting spatial mosaic” governs the heterogeneity in ecosystem patterns and processes on the landscape ( Goldammer and Furyaev 1996 ). In forest ecosystems where dominant species are long-lived, mature trees may provide a buffer against extreme weather such as drought or heat waves, but fi res and other disturbances such as insect outbreaks eliminate the buffering of the canopy, leaving a hotter and drier microclimate conducive to the establishment of new species. In a warming climate, fi re is expected to amplify and accelerate changes in forest composition, spatial pattern, and structure ( Littell et al. 2010 ; Loehman and Keane 2012 ; Raymond and McKenzie 2012 ; Cansler and McKenzie 2014 ). Anticipating these changes will be a key to successful forest management and conservation.