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Forests and Climate Change: The Facts
 As we work to combat climate change, Australia must commit to reducing carbon emissions and improving carbon storage. Conserving the nation's forests and woodlands is one the easiest, cheapest and fastest ways that we can start to achieve both these objectives. Forests play a critical role in influencing the Earth's climate. Trees are the lungs of the earth, sucking in carbon dioxide and releasing oxygen, essential for the survival of life on this planet. Whilst young trees initially draw in carbon at a faster rate, older forests can play a more significant role because they store far more carbon than young forests. Old Growth Forests - Global Carbon Sinks Like a giant safe-deposit box, old growth forests lock in vast amounts of carbon. As trees and undergrowth grow they draw in carbon dioxide. Over centuries, this carbon is slowly cycled into woody  debris
and forest soils. Ancient old growth trees, can store tonnes of
carbon. After hundreds of years, old growth forests can contain over
1200 tonnes of carbon per hectare (Dean, C. et al 2003).Unfortunately much of Australia's remaining old growth forest is threatened by logging. Research shows that it is better, for climate change, to leave old growth forests in the ground rather than logging them and converting them to regrowth or plantations. As forests age, they build up a larger capacity to store carbon in wood, soil and woody debris. Logging undermines this capacity. American and European research indicates that, because old growth forests are able to store much larger amounts of carbon, conversion of old growth forests to younger forests will lead to massive carbon losses to the atmosphere (Harmon, M. et al 1990, Schulze E. et al 2000). Australian research also demonstrates that, when an old growth forest is logged and converted to regrowth forest managed on 80 year rotations, the carbon storage capacity is reduced by two thirds (Dean, C. et al 2003). Logging old growth forests results in a major climate change impact. Based on these studies, the carbon dioxide emissions from Victoria’s logging alone is estimated to be almost 10 million tonnes. This is the equivalent to the emissions generated by adding almost 2.4 million cars onto the roads each year.  Forest Soil: A Growing Carbon Bank Scientists are beginning to understand that old forests continue to sequester carbon even when they have reached maturity. This contradicts logging industry claims that the carbon uptake in old forests is matched by emissions. The rich soils found in old growth forests represent vast carbon stores. Globally, over two-thirds of the carbon in forest ecosystems is contained in soils and associated peat deposits. Research shows that these soils contain far more carbon than originally thought and that they continue to sequester carbon as the forest ages. Old growth forest soils are now being recognised as major terrestrial carbon sinks (Zhou, G. et al. 2006). Wood products: The logging industry claims that wood products sourced from old growth forests store carbon and hence, balance out the effects of conversion. In reality, only a tiny fraction of wood sourced from old growth forests goes to long lasting timber products. The vast majority of wood from these forests (approximately 80%) goes into short lived products such as paper and cardboard which decompose and release carbon very quickly. So, carbon storage in wood products can never make up for the loss of carbon storage in old growth forests. American studies show that, even  when storage of carbon in wooden buildings is included, logging results in a net flux of CO2 into the atmosphere (Harmon, M. et al 1990).Logging Aggravates climate change: Logging and land clearing are the world's second biggest greenhouse polluters after fossil fuels, producing 20-25% of global greenhouse emissions. In Tasmania, land use change and forestry is listed as the single largest source of greenhouse gas emissions. Logging old growth forests, scorching the soil with high intensity burns and transporting wood products long distances leads to massive carbon emissions. Replacing natural forests with tree plantations destroys biodiversity, the web of life that supports and nourishes all plants and animals. Old growth and high conservation value forests should be protected from logging and forest management practices should be reformed to reflect the importance of forest carbon storage.  Wood fired Power: While logging old growth forests leads to increased carbon emissions, burning native forests for electricity generation represents a worst case scenario. The Tasmanian Government still supports burning native forests in furnaces to produce electricity. This archaic practice is promoted as an alternative to fossil fuels. However, in some cases, burning wood from native forests to generate electricity may be worse in terms of greenhouse emissions than burning coal or other fossil fuels. When old growth forest is logged to supply wood for electricity generation, as is planned in Tasmania, emissions from burning timber are compounded by the loss of carbon storage. Other Benefits: Whilst conserving our old growth forests will make a major contribution to tackling climate change, it will also yield major benefits such as: protecting water catchments, providing critical habitat for threatened species, maintaining biodiversity and enhancing tourism opportunities.  Solutions: Australian Governments can make swift and lasting cuts to greenhouse emissions by: • Immediately protecting Australia's remaining old growth and high conversvation value forests • Ending land clearing and conversion of native vegetation • Encouraging appropriate incentives for maintaining carbon storage in native forests Of course, conserving old forests is not a solution in itself. But it is an effective complement to other mitigation measures. The coalition Government has allocated $200 million to help end deforestation in developing countries, without spending a cent to stop the massive carbon emissions generated by logging in our own country. Australia must clean up its own backyard before it can adopt the role of a global policeman on forests and climate change. Whilst any moves to curb deforestation and emissions across the globe are positive, developing countries cannot be expected to follow the lead of a country which still generates massive carbon emissions by destroying its own remaining old growth forests. What you can do:  • Write to Federal and State political representatives and ask them to include protection of old growth forests in any policy to tackle climate change • Engage in the Australia wide campaign to protect old growth forests • Consider placing conservation covenants on any forest and particularly old growth on property you own • Choose timber and paper products from recycled or non native forest sources • Vote for the forests. (Authorised by W.Mooney, 21 Lucas Rd, Lucaston, 7109) See the take action page for more info on what you can do. References: Dean, C. et al. Growth Modeling of E. regnans for Carbon Accounting at the Landscape Scale. CRC for Greenhouse Accounting. Australian National University. 2003. Harmon, M. et al. Effects on Carbon Storage of Conversion of Old-Growth Forests to Young Forests. Science, Vol. 247. 9 February, 1990. pp. 699-701. Schulze E. et al. Managing Forests After Kyoto. Science. Vol 289. 22 September, 2000. pp. 2058-2059. Forestry Tasmania. Annual Reports. Government of Tasmania. 2006 Draft Climate Change Strategy. Zhou, G. et al. Old-Growth Forests Can Accumulate Carbon in Soils. Science. 1 December 2006. Vol. 314. no. 5804, p. 1417. |