Forest disturbance accelerates thermophilization of understory plant communities

摘要: Summary 1. Climate change is likely to shift plant communities towards species from warmer regions, a process termed ‘thermophilization’. In forests, canopy disturbances such as fire may hasten this by increasing temperature and moisture stress in the understory, yet little known about mechanisms that might drive shifts, or consequences of these processes for diversity. 2. We sampled understory vegetation across gradient disturbance severity large-scale natural experiment created factorial combination forest thinning wildfire California. Using information on evolutionary history functional traits, we tested hypothesis should increase community dominance with southern-xeric biogeographic affinities. also analysed how climatic productivity mediates effect severity, quantified trait response disturbance, investigate potential behind thermophilization. 3. The proportion north-temperate flora decreased, while increased, greater less closure. Disturbance caused reduction productive (wetter) analyses suggested colonizing after severe be adapted increased water stress. Forests intermediate where abundances northern southern were most equitable, had highest stand-scale 4. Synthesis: Canopy accelerate shifts via its effects microclimate at small scales. Understory diversity can enhanced regimes promote coexistence different