Yeah that burn makes no sense to me at all. Extremely confused.
Yes it can be an extremely confusing to understand BG. Here are some extracts from a study manual of mine. This is a VERY BASIC explanation on why they use fire in the Wet Tropics to maintain forest and animal diversity.
It has been estimated that rainforest, in some areas, is expanding at the rate of 1.25m per year. This sounds like good news until we look at some of the habitats it is taking over.
Wet sclerophyll forest has similar requirements to rainforest, particularly with regard to rainfall. It is generally found on the western margins of Rainforest and in isolated pockets such as hill tops but cannot exist on drier areas where dry sclerophyll forest takes over. Unlike rainforest, however, trees of the wet sclerophyll, such as flooded gum (Eucalyptus grandis), need open well-lit conditions to germinate and develop. Where rainforest species are moving in and forming a dense cover, shady conditions mean that eucalypt seedlings cannot establish themselves. An area where invasion is in progress is typified by a canopy of tall eucalypts with an understorey of rainforest - but no eucalypt saplings.
So why is this happening? It is likely that the rainforest margin has, in the past, been controlled by disturbance, primarily fire. Wet sclerophyll and rainforest have very different reactions to fire. Rainforest (although it does not normally burn) cannot survive repeated fires, whereas sclerophyll plants can tolerate and even require it.
In a marginal area, therefore, fires will kill young rainforest species allowing sclerophyll species to remain. The Wet Tropics is a diverse area. While its rainforests are its most celebrated feature they are by no means the only vegetation communities. Once an area has been taken over by rainforest, however, the change is irreversible because it does not burn easily. Therefore, it seems that fire is necessary, in certain circumstances, to limit rainforest in the Wet Tropics so that forest diversity can be maintained.
Altered fire regimes: Aboriginal use of fire in land management has shaped the Australian landscape. Traditional mosaic burning, which promoted regrowth of grasses and encouraged game into the area, also helped avoid severe wildfires by preventing a build-up of fuel.
However, various areas of the Wet Tropics respond differently to fire, and careful management is needed to maintain healthy and diverse ecosystems.
The Wet Tropics Management Authority works to manage fire with the Queensland Parks and Wildlife Service, the Queensland Fire and Rescue Service, the Rural Fire Service and Aboriginal communities. Research and monitoring programs will give us a better understanding of the complex relationship between fire and the different ecosystems of the region.
Vegetation types that require active fire management in the Wet Tropics:
Map Eucalypt forests and woodlands: These open forests need regular mild fires to survive. The seeds of some species germinate in the ash bed after fire, and rely on fire to limit the competition from shrubs and grasses. Cool fires reduce the build up of grasses, undergrowth and leaf litter that could fuel a more intense and destructive fire.
Damaging fires are most likely to occur at the hottest and driest time of year, usually from October to January, when they can threaten native plants and animals over huge areas of land.
To avoid this, the relevant authorities light smaller, controlled fires during the winter months from June to September, when there is still moisture in the grass. However, they can be done latter if required.These hazard reduction fires are usually carried out in a mosaic pattern every three to five years.
Hope this info helps you understand the process a bit better BG or confuse us all a bit more...lol
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