Harvesting Australia’s sustainably managed forests can positively mitigate net carbon emissions – with the Victorian Government’s decision to close native forestry having a negative impact on carbon emissions and, therefore, the climate. That is according to a new report, A review of the impacts of sustainable harvesting, non-harvest management and wildfire on net carbon emissions from Australian native forests, authored by Dr John Raison, the CSIRO’s former chief research scientist.
According to Dr Raison, the Andrews and Allan governments leaned on studies that “overestimated the possible benefits of ceasing harvesting because they have either been incomplete, used inappropriate parameters to estimate components of the total carbon balance, or overestimated the rate of carbon gain in older forests and the ability of unharvested forests to store carbon for the long term.”
“This has led to the incorrect conclusion that cessation of harvesting would provide lower long-term carbon emissions than sustainable management for wood production. A case study using the carbon balance of Victorian 1939 regrowth mountain ash forest managed for sawlog and pulpwood production on a rotation of 75 years showed that Victorian Government statements that harvesting results in significantly increased carbon emissions are incorrect.”
Dr John Raison, Australia”s former top research scientist for the CSIRO on the decision by the Victorian state government to close it’s forest industry.
Dr Bill Jackson, Acting President for Forestry Australia, Australia’s peak body for forest scientists, said the research has major implications for developing new emission reduction methods under Australia’s new ACCU scheme: “This paper demonstrates the complexity in accounting for the impacts of changes to forest management on carbon stocks and greenhouse gas emissions from Australian native forests.”
“Assessing carbon impacts of forest management needs to consider the full life cycle of forest management, wood production, processing, use and disposal or reuse,” Dr Jackson said. “The outcome depends heavily on assumptions about initial conditions, harvest intensity, timber recovery, lifetime of forest products, the impacts of wildfire and the time frame of the analysis.”
Carbon management must be assessed using a full lifecycle analysis
Dr Raison said that carbon management in native forests must be integrated at the landscape level with the management of other forest values and attributes: “Changes to carbon stocks in Australian native forests are driven much more by extensive wildfire than by harvesting.”
“Harvesting affects only a small proportion of the forested landscape, and the carbon in annual log harvests equates to only about 0.6% of Australia’s total net anthropogenic greenhouse gas (GHG) emissions…adding carbon emissions from the decomposition or combustion of slash produced during harvest increases this figure to 0.8%.”
“These carbon removals from the forest are offset by carbon sequestration in new regrowth and are supplemented by benefits derived from harvested wood. In contrast, in very bad fire seasons such as the ‘Black Summer’ of 2019/20, carbon emissions were about twice Australia’s annual anthropogenic GHG emissions and about 200 times greater than carbon removals in wood plus emissions from logging slash.”
“When examined at the landscape scale, there is no evidence that harvesting leads to increased area burnt, fire severity or carbon emissions caused by wildfires. However, future wildfires in the large and contiguous areas of thick regrowth created after Black Summer poses a major threat to carbon stocks in all forests in the coming decades.”
“Timber harvesting, providing it is well conducted in carefully selected parts of the landscape, can provide sustainable ongoing carbon benefits. A similar conclusion has been reached in numerous international studies.”
Dr Raison on the importance of selective timber harvesting in Australia’s native forests.
The timber link to the Koala threat is Poor Science.
In July, Dr Raison said, “Land-clearing, severe wildfires and urbanisation are clear threats to koalas, but well-regulated timber harvesting (in North-East NSW, the site of the proposed NSW Koala Park) are not. Dr Raison, responding to claims by Professor David Lindenmayer in the Canberra Times, said the unsustainability of harvesting in native forests is “inconsistent with the science and forestry practices.”
“Sustainable harvest and use of wood products does not, as claimed by Lindenmayer, increase net carbon emissions from native forests. Detailed life cycle analyses show the opposite and are consistent with the IPCC (the Intergovernmental Panel on Climate Change.”
Dr John Raison, former chief research scientist at the CSIRO, in the Canberra Times (July 25, 2024) responding to Professor David Lindenmayer’s July 13, 2024 contribution, Native forest logging has no place in Australia, but there is a solution.
“Economic analyses for harvested native forests are generally flawed because they exclude the benefits of wood processing and use, as well as important community benefits such as fire protection, road infrastructure, and water production,” Dr Raison said. “It makes no sense to restrict wood supplies from well-managed native forests based not on science, but purely on green ideology.”
- For more information about Dr Raison’s latest research, click here to read the research paper in full.
