Australian National University ( ANU) researchers have discovered that the nation's forests are the world's best at storing carbon, a key weapon against climate change.

The ANU scientists measured 132 forests around the planet and found that mountain ash forests in Victoria's Central Highlands were the most carbon-dense of all.

Researcher Brendan Mackey said on Tuesday it had previously been thought that tropical forests were the richest in carbon.

"This is a real surprise because most people think tropical forests store the most carbon, but instead its forests in the temperate region that have the most," Mackey was quoted by the Australian Associated Press as saying.

Victoria's forests were so rich in carbon because they lived in a cool climate, which slowed down the decay of the trees, the researchers said.

The trees were very old - up to 350 years of age - which meant they grew heavy, dense wood, and the forests had not been logged.

All trees absorb carbon dioxide and store it as they grow, but some forests lock up more carbon than others.

Carbon dioxide released into the atmosphere is one of the main causes of climate change.

(Xinhua News Agency June 16, 2009)