Climate changes and wildfire alter vegetation of Yellowstone National Park, but forest cover persists

Jason A. Clark; Rachel A. Loehman; Robert E. Keane

doi:10.1002/ecs2.1636

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Climate changes and wildfire alter vegetation of Yellowstone National Park, but forest cover persists

Jason A. Clark·Rachel A. Loehman·Robert E. Keane

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Abstract

We present landscape simulation results contrasting effects of changing climates on forest vegetation and fire regimes in Yellowstone National Park, USA, by mid-21st century. We simulated potential changes to fire dynamics and forest characteristics under three future climate projections representing a range of potential future conditions using the FireBGCv2 model. Under the future climate scenarios with moderate warming (>2°C) and moderate increases in precipitation (3–5%), model simulations resulted in 1.2–4.2 times more burned area, decreases in forest cover (10–44%), and reductions in basal area (14–60%). In these same scenarios, lodgepole pine ( Pinus contorta ) decreased in basal area (18–41%), while Douglas-fir ( Pseudotsuga menziesii ) basal area increased (21–58%). Conversely, mild warming (<2°C) coupled with greater increases in precipitation (12–13%) suggested an increase in forest cover and basal area by mid-century, with spruce and subalpine fir increasing in abundance. Overall, we found changes in forest tree species compositions were caused by the climate-mediated changes in fire regime (56–315% increase in annual area burned). Simulated changes in forest composition and fire regime under warming climates portray a landscape that shifts from lodgepole pine to Douglas-fir caused by the interaction between the magnitude and seasonality of future climate changes, by climate-induced changes in the frequency and intensity of wildfires, and by tree species response.

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Source-reported bounding extent: 44.44750680513074° to 44.99394031891056° latitude; -111.0498046875° to -110.3082275390625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Jason A. Clark, Rachel A. Loehman, Robert E. Keane. 2017-01-25. Climate changes and wildfire alter vegetation of Yellowstone National Park, but forest cover persists. https://doi.org/10.1002/ecs2.1636

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