SO WHERE are the world’s most carbon-rich forests? Not the tropical rainforests of the Amazon, Borneo or Africa’s Congo Basin, according to research by the Australian National University. They are the tall, old-growth mountain ash forests of Victoria’s Central Highlands — a 90-minute drive east of Melbourne.
The researchers studied 132 forests from around the world to discover the regions that stored the most carbon. Their findings, published in the US-based Proceedings of the National Academy of Sciences, one of the world’s most-cited scientific serials, is a surprise because conventional wisdom says that tropical forests store the most carbon.
So why our forests? The conditions are perfect. These forests occur at a confluence of environmental conditions that lead to high rates of plant growth and, because they are cooler, decay rates are slower. In short they grow fast but decay slowly. And they are very old — at least 350 years, growing dense heavy wood. That’s important because the amount of carbon stored is due to volume and density. Also, these trees have not been subjected to logging.
The problem is, these very same forest types are being intensively logged for woodchips, mostly bound for Japan. These trees are not only the best at producing carbon; unfortunately for them, they are also some of the best for producing high-quality paper. To add insult to injury, several of Melbourne’s water catchments are among those logged.
ANU science shows that for as long as these forests are logged, their carbon-carrying capacity is reduced by up to 60 per cent, not to mention the emissions from logging and post-logging regeneration burns. If we stopped logging all the forests of south-eastern Australia, and we now have enough wood in plantations to do that, we would avoid emissions equal to 24 per cent of the 2005 Australian net greenhouse gas emissions across all sectors.
Ironically, the plantation-based timber industry is under great economic stress, with several major wood plantation growers in receivership. This is the right time for Premier John Brumby to develop an integrated industry rescue and climate package, which creates green jobs in the plantation sector and focuses management of our native forests on emissions. Read more here
Gavan McFadzean is the Wilderness Society Victorian campaigns manager.