ENVS3008 Sam Banks - Fire and genetic diversity Why is genetic diversity important? Genetic diversity related to DNA sequences. It is important that there is genetic diversity within a region as it effects the adaptability of populations/ species to environmental change. There is no 'perfect organism' but the environment is always changing; so must those that live within it. It also dictates individual fitness which promotes disease resistance, survival and reproduction output which is reduced by low individual genetic drivers (inbreeding) e.g. Tasmanian Devils are afflicted by tumour disease because they fight a lot and are all genetically identical. Genetic diversity is also driven by fire regimes. Aspects of fire 'regimes' and demographic processes that influence genetic diversity within sub-populations of organisms. Migration distance has the most significance on genetic diversity within a sub-population. Low dispersity most significant as has profound effect on the survival rate. Followed by fire severity (mortality), fire size and fire frequency. Inter-relationship between fire, habitat suitability, and the 'founder effect' in determining genetic diversity in Mallee emu-wren. The wrens favour environments which have an IFI of 30 years. Can't live in an environment much past this and cannot live in an environment just post fire as it effects the ecosystems so differently. They shift patches of habitat for suitability and then move on. However, now as there are more frequent fires there are less options for suitable homes so has a founding effects. Population decreases and so only a small proportion of the original population remain. Marta Yebra - Remote sensing of bushfires Focus Importance of, and remote sensing of, Live Fuel Moisture Content (LFMC) in bushfire studies. Remote sensing can be used for fire management. Moisture content affects fire occurrence and behaviour. The higher the fuel moisture content the harder the fuel is to light. As the heat must first evaporate all the water and then it can light; the more water the long this takes to evaporate. Post-fire applications of remote sensing for studying bushfires. Can be used to map and make predictions of possibility of future fire. Immediately, it can be used to examine burnt leaves and carbon or burnt area and emissions. The build-up of vegetation can be tracked to make predictions about fuel load etc. Jim Gould - Fire in dry eucalypt forest (also fuel modelling practical)
Dynamics of Fuel Hazard Scores with time since last fire. The shorter the time since fire the higher the fire danger rating with the highest fire danger being 5-8 years since last burnt. Under 5 years has a marginally lower fire danger rating and that is because regrowth isn't quite at its peak yet. The lower the fire danger the higher the intensity of the fires. As long unburned areas have large fuel loads which once lit are more difficult to control. Inputs of the Dry Eucalypt Forest Fire Model The inputs of this model are fuel age, fuel hazard score, fuel hazard rating and near-surface fuel height. Andrew Sullivan - Fundamentals of