Abstract
The length of inter-fire intervals plays a central role in determining species composition in plant communities across the world. Recently, extremely short intervals have been identified as a threatening process for the ongoing persistence of species in a number of vegetation types.
A variety of methods were used to determine a minimum fire-return interval suitable for the maintenance of biodiversity in the species-rich and fire-prone northern sandplain shrublands of Western Australia. Several species considered vulnerable to high fire frequency were selected for demographic analysis with space-for-time substitution used to determine key life-history attributes such as time to produce adequate seed for self-replacement. Community-level resilience was captured using pre- and post-fire plot comparisons in recently burnt vegetation that was re-burnt by experimental fires. The stability of each site was measured in terms of resemblance to pre-fire composition at 12 months after fire. The effect of post-fire rainfall on seedling mortality was also examined as a factor independent of fire interval length.
The results were combined to identify a minimum return interval that has provided land managers with a sound ecological basis for determining an appropriate prescribed burning regime for the community.