The Effect of Fire Intensity on Vegetation Succession on a Sub-Xeric Heath during Ten Years after Wildfire

Abstract

Many studies indicate that fire intensity has a marked effect on subsequent vegetation recovery. However, evidence from natural fires is still sparse. We studied vegetation succession during ten years after a wildfire on a sub-xeric, pine dominated coniferous forest. The fire affected four adjacent patches differently and thus created a natural fire intensity gradient. Postfire vegetation data was analysed using non-metric multidimensional scaling and MANOVA. The clearest indication of fire intensity was provided by herbaceous colonizers. Recovering dwarf shrub cover and residual and invader moss cover provided additional evidence for observed differences between the four areas. Despite of initial dissimilarity, community composition became increasingly similar on the different areas during the study period. In conclusion, variation in fire intensity had a clear impact on postfire recovery in natural conditions. Fire disturbance also clearly enhanced local species richness and diversity. Our results indicate that habitat factors play a considerable role in the nature of vegetation recovery following wildfire.