Recovery of subalpine grasslands 15 years after landscape level fires

Abstract

As conditions warm, previously rare landscape level fires are more likely to affect vegetation in the Australian Alps including in subalpine grasslands. The recovery of this community was assessed using paired unburnt and burnt plots (30 × 20 m) at 10 sites 15 years after largescale fires that burnt >70% of the subalpine zone in Kosciuszko National Park. There were few significant differences found: higher cover of shrubs (17.8% burnt vs 11.3% unburnt plots), and taller vegetation (22.6 vs 19 cm). However, vegetation cover (97%), species richness (38 taxa), composition and limited presence of invasive plants (10 species, 8.5% cover) were not significantly different. This differs from results six weeks and one year post-fire, when there were clear differences in the cover and composition of vegetation. These results indicate that subalpine grasslands recover from single fires, but with warmer and drier conditions becoming more common, and repeat fires in some areas, the distribution, structure and composition of this and other communities in the Australian Alps will change.