Victorian fires - let evidence prevail

The following article was published in The Canberra Times on 23 Feb 09. It was written in response to the vast amount of poorly informed and value-laden critique of land management that we saw in the media post Black Saturday. If we do not base policy on evidence then we will risk repeating mistakes of the past. To this end, colleagues and I have commenced an objective and quantitative study on the links between land management and building damage experienced during the Black Saturday fires of 7 Feb.

This post fire period has seen many prominent commentators, including politicians, journalists, academics and even an expert on women’s rights observe that a lack of fuel reduction in our forests—by prescribed burning or clearing—is to blame for the devastation of 7 February 2009.

These comments paint a picture of fires that raged through forest of uniformly high fuel loads.

Mapping available on-line from the Victorian Government illustrates a different reality. These maps show the Victorian fires moved across a mosaic of forest that has been prescribed burnt and logged, converted to plantations and cleared. Marysville had a large area around it that was prescribe-burnt in 2008 over which the fire advanced. Callignee is surrounded by a mosaic of cleared land and forest.

Fires burnt destructively in these places in spite of areas of reduced fuel loads.

Forest fires spread due to a combination of wind, humidity, temperature, fuel load and slope. Research indicates that when weather conditions are extreme—as was the case on 7 February—the spread of fire becomes more responsive to wind than to fuel loads.

The suggestion that all forest should be prescribe-burnt also fails to recognise that this is not feasible. Ecologists, foresters and fire-fighters who have been associated with wet forests that occur in areas burnt by the Murrindindi complex of fires understand that these forests carry fire only in hot, dry seasons. In other words, they cannot be safely prescribe-burnt. The native vegetation in these wet forests has burnt and regenerated under a regime of infrequent intense fires for millennia.

Another argument aired in the media is the need to relax native vegetation clearing laws—and thereby enable landholders and public authorities to remove native vegetation from the land they manage. Bushfire regulations currently permit some clearing around infrastructure in Victoria and other parts of Australia.

However, relaxing vegetation laws further to permit broadscale clearing—clearing over larger areas—carries other risks.

Until recently Australia was one of the principal land clearing countries in the world—along with Brazil, Indonesia, The Democratic Republic of Congo and Russia. Land clearing laws in Australia have been tightened in several states over the last decade for several reasons.

Maintaining mature natural forests is the most cost-effective way to provide high quality drinking water. Major catchments in most cities of Australia, including Melbourne, remain forested for this reason.

Broadscale clearing leads to problems that affect agricultural production such as soil loss and salinity.

Ceasing broadscale clearing was reported by an advisory group appointed by the previous Howard Government as the most cost-effective way to conserve biodiversity in this country.

Land clearing globally accounts for 20% of human greenhouse gas emissions. Forest wildfires have a comparatively minor impact on greenhouse gas emissions because they do not incinerate the major carbon pools in forests and the forests regenerate.

A reduction in land clearing is the principal reason why Australia has met its Kyoto target and Australia now funds programs to reduce deforestation—and its attendant greenhouse gas emissions—in other countries such as Papua New Guinea.

It would therefore be ironic if the fires in Victoria result in an increase in land clearing that, in turn, contributes to further greenhouse gas emissions and ultimately a greater likelihood of extreme weather events like those on 7 February.

Forests are a major tourist attraction and therefore economic resource to many of the towns that have been affected by these fires.

And finally, the forest itself attracts many people to live in these areas.

What is the right balance between modifying forests and modifying the way people live in forests in order to improve public safety? Australia needs to have this conversation.

It concerns me that a disproportionate focus on fuel management in our forests will not guarantee life and property under extreme weather events such as those on 7 February and create a host of other problems for us with respect to water quality, biodiversity, greenhouse gas emissions and the economies of forest communities.

Dr. Philip Gibbons is a Senior Fellow at the Fenner School of Environment and Society at The Australian National University and a former fire fighter for the Victorian Government.