PhD Scholar

Relative importance of fire regimes, environmental gradients and climate change for rainforest distribution in the Sydney region.

E-mail: carola.kuramotto@anu.edu.au

The distribution of vegetation communities across landscapes is determined by a range of environmental factors including historical fire regimes, climatic variation, soil fertility and characteristics; topography, water availability and plant vital attributes. Various theories have been proposed to explain current distributions of plant communities, and many have identified fire as an important component. These theories demonstrate that the probability of plant species remaining in particular localities following fire is a function of the fire regime (in particular fire frequencies and intensities), and the species' post-fire regeneration attributes.

The distribution of rainforests is of particular interest. Although some rainforest species are able to resprout after a fire, there is evidence suggesting that frequent and severe fires can eliminate these species from the landscape. To study the influence of fire regimes and other environmental variables on rainforest distribution, I am using information from the Sydney region. This area provides an ideal study site as the relatively high incidence of both natural and anthropogenic fires appears to be in direct conflict with rainforest persistence. Currently, fire management practices in the Sydney region aim to protect people and property, while simultaneously maintaining biodiversity values. However, these objectives are often in conflict as hazard reduction prescribed burning can eliminate species that require long periods to reach maturity. Further, the occurrence of severe fires affecting large areas, such as those observed during the 2003 fire season, is expected to be detrimental for certain species. As many rainforest species require fire-free periods of at least one hundred years to reach maturity, shorter fire intervals would eliminate them from the landscape. This problem is likely to be exacerbated under climate change conditions, which fire frequency and severity have been forecast to increase. This project is investigating the key factors contributing to the persistence of rainforest in the Sydney region, and how incompatible fire regimes may alter rainforest distribution. Such information is vital for developing optimal management strategies for this significant component of the landscape under present and changed conditions.