A post-fire vegetation recovery survey of K’gari Great Sandy National Park was conducted in April 2021, and the condition of the vegetation compared to benchmark values using the BioCondition tool.
Thirty sites were permanently marked and sampled in nine regional ecosystems. Most burnt vegetation comprised eucalypt woodlands, Melaleuca open forest, heathlands and peat swamps. These all showed remarkable resilience to the fire with no apparent loss of species and substantial vegetative regeneration occurring on many burnt individuals. There was very limited burning in the Syncarpia hillii, Lophostemon confertus tall open forests or rainforests. The fire varied in intensity, and the proportion of tree deaths ranged widely, but high-intensity fire caused widespread death of trees.
For instance, within a Regional Ecosystem (RE), 12.2.6 is described as Eucalyptus racemosa subsp. racemosa open forest on dunes and sand plains, there was an increase in tree death and reduction in overall BioCondition score with increasing fire intensity. However, observed recovery through widespread vegetative resprouting and some species establishment from seed will most likely result in improved BioCondition scores as the structure is restored. In some burnt areas, recovery was characterised by mass germination of Acacia penninervis var. longiracemosa, A. flavescens and Dodonaea viscosa subsp. burmanniana into dense layers.
Across all 19 sites with previous site data from 1995-2005 that were resampled, the post-fire vegetation appears to contain a similar species composition to that recorded from 1995 onwards. Robust recovery is occurring across all of the nine REs sampled, apart from the coastal Casuarina equisetifolia subsp. incana woodlands and Banksia integrifolia woodlands on the frontal beach ridges and high dunes. In this latter vegetation, the death of most adult trees and subsequent lack of regeneration of the dominant tree species, despite adequate follow-up rainfall, is a major concern.
A copy of the full report can be downloaded here.
Article contributed by Dr John Neldner, Queensland Herbarium