24. Fire, vegetation and climate change in Australasia

First meeting was held 20-23 February, 2007 at Network Headquarters in Sydney. Second meeting was held 16-19 July 2007, with some participants continuing through the subsequent week. The third meeting was held 21-25 July 2008.

PARTICIPANTS Sandy Harrison (U Bristol, UK), Leader John Dodson (ANSTO, Sydney) Leader David Bowman (University of Tasmania) Pauline Grierson (U Western Australia) Simon Haberle (ANU) Geoff Hope (ANU) Pandora Hope (BMRC) Guy Midgley (South African National Botanical Institute) Scott Mooney (UNSW) Ross Bradstock (U Wollongong) Rewi Newnham (Plymouth U) Stuart Pearson (Land and Water) Colin Prentice ( U Bristol) Fiona Scarff (Macquarie U) Lynley Wallis (Flinders U) Janet Wilmshurst (Landcare Research, New Zealand) Cassandra Rowe (U Bristol) Rebecca Fraser ( Swansea U) Josephine Brown (Monash U) Yan Zhao (U Bristol, UK) PARTICIPANTS AT JULY 2007 MEETING Harrison, Dodson, Bowman, Bradstock, Brown, Fraser, G Hope, Mooney, Prentice, Rowe, Scarff, Zhao PARTICIPANTS AT JULY 2008 MEETING Harrison, Dodson, Bowman, Bradstock, Brown, Fraser, Mooney, Prentice, Rowe, Scarff, Matthew Coller

Feb 07> Jul 07> Jul 08>

This project's aims include reconstruction of Australasian palaeovegetation, together with an improved categorization of plant functional types from the perspective of fire, together with a fire-enabled version of the general vegetation model LPJ.

The project is collaborative with QUEST. The project is also known as QUAVIDA, and a more detailed website is maintained here.

Achievements and plans arising from the second meeting include the following:

1. The pollen, plant macrofossil, phytolith and 13C isotope databases are now ca 90% complete. The charcoal database is less complete but substantial progress in data entry has been made.
2. A taxonomic clean-up of the pollen data base has been implemented. This was necessary because of the use of non-standard, mis-spelt or incorrect taxon names in the original sources. The original taxon list had ca 5600 entries. The clean-up has reduced this to a more manageable list of 1632 unique taxa.
3. Refinements were made to the PFT classification agreed at the last meeting to ensure that terminology was applied consistently.
4. A strategy for implementing the new PFTs within the current modelling framework was developed. Values need to be specified for 12 parameters for each PFT. An examination of the PFT parameter-values used in the current version of LPJ-SPITFIRE showed that these are not appropriate in the Australasian context, and better parameter values are currently being derived from appropriate existing compilations (e.g. GLOPNET, VAData) and from the literature.
5. Questions to be addressed with the new LPJ-SPITFIRE include:
   •  What would be the nature of Australasian vegetation if there were no fire?
   • What would be the nature of the Australasian vegetation if ignition were not limiting?
   • At what point does further increase in ignitions have no impact on the area burnt?
   • Are recent large fires in Australasia attributable to climate variability, anthropogenic activity or land-use change?
   • Can we explain observed changes in Australasian vegetation and natural fire regimes over the past 80,000 years as a consequence of known changes in orbital, atmospheric composition, changes in sea level and ice sheets?
   • Do climate-driven changes in vegetation cover have feedbacks to the climate that are sufficiently large to produce a more realistic simulation of observed vegetation patterns and natural fire regimes during the past 80,000 years?
   • Can we (alternatively) explain observed changes in Australasian vegetation and fire regime over the past 80,000 years as a consequence of human activity?
   • Could vegetation changes of a scale consistent with the fossil record have produced sufficiently large feedbacks to substantially modify the climate?
   • Can we estimate the level of human burning necessary to produce observed vegetation and fire regimes through time, and is this consistent with archaeological/anthropological perspectives?
   • What impact will projected future climate changes have on vegetation and fire regimes in Australasia?
   • Can fire suppression and/or fuel manipulation mitigate future-climate impacts on vegetation and fire regimes?

Last updated July 2008