Forests in New South Wales could become net carbon emitters in coming decades, undermining state government efforts to reach net zero emissions, according to a report by one of its own agencies.
The Natural Resources Commission has warned the Perrottet government the benefits the state’s forests provide are degrading and will continue to degrade without “major intervention”.
The report, published in December, urges the government to avoid “business-as-usual management approaches and reactive policy decision making”, saying this would lead to “sub-optimal outcomes at best, or ecosystem and industry collapse under worst case scenarios”.
The management of forests on public and private land is expected to be an issue in the March state election.
Some independent candidates running in key Sydney seats are calling for an end to logging of native forests. There have also been broader calls from the Greens and environment groups to address the state’s high rate of land-clearing.
The NRC report comes after the release of annual accounts for NSW Forestry Corporation, which showed its hardwood or native timbers division ran at a $9m loss in 2021-22, largely due to flooding on the north coast and costs associated with bushfire recovery.
The report says the state’s forests are under increased strain from combined pressures of invasive species, population and economic growth and the intensification of urban and agricultural land use.
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It states that streamflow in NSW forests, particularly on the south coast, had been declining for 30 years and ongoing reductions would have “major implications for future water security in NSW”.
It also warns the unprecedented fires of 2019-20 “will not remain an outlier”.
As global heating drives more frequent fires and droughts there was a risk, it says, that these disturbances could trigger “ongoing cycles of decline in key areas such as forest regeneration and soil organic carbon” by reducing the capacity for full recovery after these events.
“In this case, forests will become a net carbon emitter in the coming decades, undermining key government commitments to achieve net zero carbon emissions by 2050,” the report states.
The NRC elaborates on this, saying it was commonly assumed carbon lost to fire would be reabsorbed by forests as they recovered and regenerated in the 10 to 15 years post-fire.
But the extent to which forests were able to recapture lost carbon would depend on their ability to fully recover and the absence of further disturbances in the recovery period, the report said.
For soil organic carbon, recovery after fires was estimated to be about 60% after 20 years but this estimate did not account for additional bushfires during this time, the NRC said.
The commission said there was a risk of a cycle of declining soil organic carbon if there were repeated fires “or other disturbances such as grazing, timber harvesting or land clearing”.
The report calls for a “major intervention” and recommends the government develop an overarching forests 2050 strategy to “systematically address” the climate crisis and other stressors.
Andrew Macintosh, an environmental law and policy professor at the Australian National University and former head of the federal government’s Emissions Reduction Assurance Committee, said more frequent fires and dry cycles caused carbon stocks in forests to fall.
He said the most important thing for governments was to introduce stronger land-clearing regulations, incentives for landowners to protect forest on private land and to reduce logging.
“If the government wanted to improve the condition of forests, the best thing you could do is stop remnant clearing and large-scale commercial harvesting of native forests,” he said.
Justin Field, an outgoing independent MLC, pushed the government in the last term of parliament to provide greater clarity about the impacts of land-clearing and land use on the state’s emissions.
“The report highlights the importance of turning around the massive increase in land clearing under the Coalition government in the last five years,” he said.
The NSW Greens environment spokesperson, Sue Higginson, said the report was “more evidence that it is time to stop the industrial-scale logging of our public native forest estate and manage them for their habitat and carbon storage functions”.
Shortly before Christmas the NSW government announced a new 2035 emissions reduction target of 70% as it tries to head off the threat of independent candidates running in Liberal party heartland seats at the state election.
Jacqui Scruby, an independent running for the seat of Pittwater, said it “doesn’t make sense to be setting emissions reduction targets and then subsidising native forest logging”.
The agriculture minister, Dugald Saunders, said there were clear rules in place for the sustainable harvest of timber in NSW.
He said half of the 2m hectares managed by the NSW Forestry Corporation was conservation land and just 1% of the total area was harvested each year.
The NRC was unavailable for comment.