Legislative Assembly for the ACT: 2009 Week 8 Hansard (25 June) . . Page.. 2987..
MR CORBELL (continuing):
microclimates of our suburbs. The urban estate reduces energy consumption to the value of $23 million per annum, and this figure rises in outyears. The 2003 fire emitted 2,833,000 tonnes of carbon by combustion—11 per cent of the total estimated carbon stock. The report concludes it may take 100 years to reach 95 per cent of pre-fire carbon stocks.
The arboretum will be a net carbon producer up to 2015 as a consequence of the removal of pines on the site to reduce bushfire risk, but it will then become a positive sequesterer, peaking at 800 tonnes in 2025 and continuing to sequester for around 200 years. It will eventually be a 70,000-tonne carbon sink. The arboretum has other environmental benefits also, such as preserving endangered tree species.
The overall conclusion in the report in relation to the arboretum is pleasing, given that the government removed the pines as a bushfire safety measure following the report into the 2003 bushfires.
The carbon sequestration audit report examined the practice of wood-chipping trees removed from the urban forest and found that it promotes the decay of timber, resulting in a faster rate of carbon emission. However, trees removed from the urban estate do provide other benefits, including mulching and the construction of wood products. Mulching, of course, also reduces water consumption and weed infestation. Converting woodland and grassland to urban land use emits 142 and 35 tonnes of carbon respectively. This impact will be taken into account in future land planning and in the development of an offsets policy, which will be examined as part of the review of the Nature Conservation Act in the coming months.
This report will help to inform policy in the ACT, including in the areas of urban and non-urban tree management, future carbon offset activity, valuing the environmental services provided by our vegetation and understanding the impact of the 2003 fires on the local carbon cycle.
The audit supports three actions outlined in the weathering the change strategy. First of all, it is a tangible product from action 43 to undertake the audit. Second, it links with action 41 to partner with key research institutions to better understand the complexities of climate change. And, third, the report's conclusions represent a strong endorsement of tree-planting programs such as action 36, the government's initiative to plan one million trees.
The report not only gives us data; it helps us to understand the impact of climate change on our ecosystem and the various mitigation and adaptation options before us. The report will help us to make better decisions about city design and how we interact with the natural environment. Parks, Conservation and Lands, within the Department of Territory and Municipal Services, has advised that it would be helpful to build on this report through additional work to measure the carbon sequestration potential of the trees in the rebuilding of the urban forest. This is a matter that the government will be progressing.
Information about the amount of carbon sequestered in the urban forest may influence the optimal age-class structure of the trees, so that the urban forest has a large