Sydney: Forests in Australia store three times more carbon than climate change experts realise, according to a study.

The largest stocks of carbon are found in Victoria and Tasmania forests, which support trees up to 80 metres tall and can contain more than 1,200 tonnes of carbon per hectare, or up to 10 times more carbon per hectare than previously realised.

"If natural forests continue to be cleared and degraded, then the C02 released will significantly increase concentrations of greenhouse gases in the atmosphere," informed Brendan Mackey, a co-author of the study.

About half of Australia's forests have been cleared in the last 220 years and the carbon stocks in more than 50 per cent of the remaining unprotected forests have been degraded by land use activities such as logging.

Mackey said the research should alert the Australian government and international agencies to 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.

Australian National University scientists have calculated that the average amount of carbon stored in unlogged natural eucalypt forests is about 640 tonnes per hectare. According to Intergovernmental Panel on Climate Change, the average carbon stock in temperate forests is only 217 tonnes per hectare.

The findings represent a breakthrough in understanding the role of forests in long term carbon storage and in helping solve the climate change problem. The authors - Brendan Mackey, Heather Keith, Sandra Berry and David Lindenmayer - found that a new approach is needed to account for carbon stored in natural forests. IANS