The Apple Isle's Bid to Feed Australia: As Proposals to Cut Irrigation from the Murray-Darling Basin Are Announced, the Search for Australia's New Food Bowl Has Shifted to Tasmania. but, What Impact Will Increased Irrigation and Land-Use Change Have on Tasmania's Ecosystems? Joe Isaac Investigates
Isaac, Jo, Ecos
The search for Australia's new food bowl has taken a new twist of late, following the release of the Guide to the Proposed Murray-Darling Basin (MDB) Plan. The plan includes recommendations to slash irrigation by up to 45 per cent in some river systems, with total cuts up to 400 gigalitres (GL). While these measures will help restore a healthy river system to the Basin, they will inevitably affect agriculture in this region, which produces more than a third of Australia's food supply.
Northern Australia has also been earmarked as a potential key to securing our food future, with calls to increase agriculture in regions that receive a deluge of rain during the wet season. A report released earlier this year highlighted environmental concerns and suggested that further dam projects in the north would be inappropriate. (1) Despite this, the northern food bowl vision is still being promoted by some politicians, including Western Australian Premier Colin Barnett.
More recently, Tasmania has thrown its hat into the ring, with Premier David Bartlett stating that 'Tasmania has all the assets and qualities to become the next food bowl of the nation, when called upon.' The Apple Isle already produces a significant amount of food, contributing more than 20 per cent to Australia's aquaculture industry, and nearly nine per cent to dairy production.
While Tasmania accounts for only one per cent of Australia's land mass, it has the highest ratio of water to land of any state, and receives up to 14 per cent of the country's rainfall. This abundant water supply underpins the food bowl vision, with the state government allocating $400 million towards 13 key irrigation schemes. Half of these are expected to be complete in the next year, while the others, if approved, will be finished by 2014. In total, the schemes would provide an additional 250 GL of water a year by 2014 to support the projected growth in agriculture. Premier Bartlett has stated this water 'will irrigate over 250 000 extra hectares of land, delivering an extra $200 million in produce, annually, at the farm gate.' The additional water will represent a 40-50 per cent increase above existing irrigation supplies.
Additionally, the Tasmanian Government's Wealth from Water initiative, to begin in 2011, will drive rapid land-use change to fuel the production of higher-value crops, particularly in newly irrigated areas.
While schemes are earmarked for all regions of the state, the largest volumes of water will be sourced from the Central Highlands and the north-east. If irrigation schemes are successful, water will be pumped to currently dry regions of the northern Midlands, which have been highlighted for land-use change from grazing to high-value produce. Water will also be directed to land in the south-central area, the Coal River Valley, and the north-east coastal region.
Chief Executive of the Tasmanian Farmers and Graziers Association (TFGA), Ms Jan Davis, estimates that in perhaps two decades or so 'we could double our current food production output.' However, Professor Jonathan West, head of the Australian Innovation Research Centre in Hobart, and often described as the brain-child behind the 'Tassie food bowl' vision, is more cautious.
'While Tasmania can increase key high-value areas including dairy, wine, aquaculture, horticulture and red meat,' says Prof. West, 'it will not make up for the volumes or food types that would be withdrawn from the Murray-Darling.'
Projections in the recently released Climate Futures for Tasmania report, prepared by the Antarctic Climate and Ecosystems Cooperative Research Centre, cast doubt on the feasibility of the food bowl dream.
According to the report, annual rainfall has already declined in the state, at levels similar to the southern mainland. While total annual rainfall is not projected to change, it is predicted to decline in central regions and the north-west, but increase in coastal areas. …