Forests on private land a climate fix
Tim Payne says Tasmanian forests can store carbon and help stop climate change
DISMISSING the impact of global warming on future generations is akin to parents denying their children disease vaccinations but on an astronomical scale.
Tasmanians cannot alone solve global warming, but we can acknowledge shared responsibility and take actions that model constructive examples for others to follow.
Many people fervently believe the harvesting of trees from native forests has played a devastating part, and have sought total preservation of all native vegetation to reduce atmospheric carbon, with a view to reducing global warming. They have succeeded in this preservation to the extent the Australian Bureau of Agricultural and Resource Economics and Sciences reported in 2018 the net area available for harvesting of Australia’s multiple-use public native forests is 14 per cent of that total forest area.
Modelling reveals this policy is counter-productive. In non-commercial forests, where trees reach maturity, the carbon storage capacity of the young trees is matched by a decline of storage within older trees, and by the release of carbon from rotting trees.
Research shows maximum carbon retention depends not just on the existence of forest but on the age and vitality of trees in it. The fundamental principle of sustainable management that Tasmanians must understand and act on is that harvesting mature trees allows younger ones to maximise the forest’s carbon retention.
The selective harvesting under careful supervision would yield a return that would discourage farmers from seeking to convert what they regard as the worthless 40ha of forest annually that is now permissible.
But in terms of locking up carbon, the harvesting of mature trees in Australian native forests is just one advantage. When that timber is put to long-term use, the carbon retaining value is substantially raised. Firstly, timber used in structures and furniture locks up the carbon within it indefinitely.
Secondly, using timber means that the need for plastic, steel, or aluminium is avoided, and the carbon emissions from their production is saved.
Farmers will gain from timber sales, which is important because these forests are regarded a liability. If forested areas were to have value in future, fire protection would feature significantly in farm operations. Without that, the wildfires of today are just a hint of what must inevitably come.
What must happen? Nationally, some action has been taken. Land owners can receive carbon credits to establish plantations, providing value along with the profits from the sale of the timber. But plantations cover less than 2 per cent of the Australian land under natural forest, which means this is little more than tokenism.
To have a worthwhile impact, private forest in Tasmania must be assessed by professional foresters where the owners accept stewardship responsibilities, and receive carbon credits in return as do plantation owners.
How can this happen?
Politicians must play a lead role by responding to the advice researchers have published to ensure Tasmanians are guided by science and not sentiment, and those politicians must confer nationally to require large emitting companies to sustain and improve carbon sequestration by minimising emissions and ensuring they pay carbon credits.
Farmers must commit to the role as stewards, and manage their forests’ commercial and carbon retention values.
Urban dwellers must shoulder most blame for global warming in Tasmania. We produce more carbon than rural areas could ever match, and much of what we export is processed in ways that adds to global warming. We are living beyond our atmospheric means.