The Mercury
By: Sue Neales
Pioneering forest research by the Australian National University has found Tasmania's native forests contain up to six times as much natural carbon than previously thought.
The ANU research team, led by plant ecologist Brendan Mackey believes the new evidence may force a "rethink'' of national and state policies that encourage logging of native forests.
Professor Mackey says the case is now compelling for national and international efforts to prevent global warming to include the losses for carbon storage caused by the degradation and logging of native forests in south-east Australia.
"We haven't really been thinking about and factoring in the carbon value of our native forests,'' Prof Mackey said.
"What we now know is that these forests are very important stocks of carbon, and it is becoming more important than ever that we think about ways of protecting them.''
Prof Mackey said that up until the publication of the new research, both the Federal Government and the International Governmental Panel on Climate Change had been forced to rely on generalised figures for the amount of carbon stored in temperate rainforests.
These figures calculated the contribution to carbon storage made by natural native temperate forest worldwide, as equal to 217 tonnes of carbon stored per hectare of forests.
But measuring carbon stored in unlogged forests across southern Queensland, NSW, Victoria and Tasmania, the ANU team found the real figure for Australian eucalyptus forests was almost three times higher at 640 tonnes of carbon per hectare.
Prof Mackey said he was astonished to find that tall undisturbed mountain ash forests in Tasmania and central Victoria stored more than double that amount.
"These gigantic trees towering above a dense lower layer of cool rainforest tree store more than 1200 tonnes of carbon per hectare,'' he said.
"This research should alert Australian governments and international agencies of the urgent need to protect the carbon stored in natural forests as part of the suite of measures needed to solve the climate change problem.''
Other key ANU findings were that:
* The carbon storage capacity of Australia's native forests, particularly in Victoria and Tasmania, had been seriously underestimated.
* Economic valuations and policy options have been misrepresented and distorted.
* Commercial harvesting of Australia's native forests leads to carbon loss and a reduction in the ability of the forests to offset harmful carbon gas emissions.
* Carbon accounting methods for forests must change from a focus on total deforestation to the losses sustained when a logged forests is no longer able to store as much carbon.
Prof Mackey said the ANU research found that 56 per cent of unprotected native forests in south-east Australia had been commercially logged. He said this meant the total capacity of these forests to store carbon was about 40 per cent below their total potential if the trees were allowed to regrow and mature undisturbed.