Forest landscape models (FLMs) are important tools used to address a wide range of forest management policy tradeoffs on public and private forests. Several recent studies using FLMs have examined the effects of forest and fuels management on future wildfire activity, carbon, water yield, resiliency, and other forest metrics. Studying longer-term (e.g. > 20 years) dynamics between management and disturbances can reveal ecosystem tipping points, feedbacks, and unintended consequences of management activities that are not otherwise observable. Most recently, applications of FLMs have provided insights on the potential effects of management on future fire and forest composition under a range of climate change scenarios. Many of these studies in the United States have used portions of the National Forest network as study areas where wildfires are increasingly impacting ecosystem services and burning into adjacent developed areas. In this study, we developed and applied a new FLM, LSim, to examine a wide range of wildfire and forest management issues on western US landscapes.
LSim integrates the Forest Vegetation Simulator (FVS) with the large-fire simulation model FSim. The resulting LSim model has the functionality to simulate spatially coordinated forest management over time under a background of large, randomly determined wildfires with models that have undergone decades of field application. This is in contrast to other FLMs that have yet to be used to guide site specific management activities as part of forest and fuels management on national forests. The LSim model provides a platform to simulate detailed prescriptions developed by silviculturalists in the field as part of forest landscape management projects.
We applied the model to the Deschutes National Forest in central Oregon, USA, to study how accelerated forest restoration might affect future wildfire. We simulated three alternative spatial treatment scenarios and three levels of management intensity (area treated) over a 50-year timespan and measured the response in terms of area burned, fire severity, wildland-urban interface exposure, and timber production.
We are also applying the model to national forests in the Blue Mountains in eastern Oregon to study the effect of climate change on future fire. At a third study area in northern Arizona we are examining alternative restoration and fire management strategies through time on fire behavior.