We must avoid the final cut

My guess is most Australians aren't aware that an area of forest and bushland the size of the MCG is currently bulldozed in Queensland every three minutes, mainly for livestock grazing. Data released this year reveals that over 1 million hectares have been cleared over the last three years, making Eastern Australia a global deforestation hot-spot alongside places like the Amazon, the Congo and Borneo. Inexcusably, we are the only advanced economy still engaged in broad-scale land clearing.

This accelerating crisis in our Sunshine State follows weakening of land clearing laws in 2012 by the previous Campbell Newman Government. The current Palaszczuk Government tried unsuccessfully to reinstate protections last year, but has pledged it will do so if Labor is returned to power following last week's Queensland state election.

The loss of our precious native vegetation is an issue not only for Queenslanders, but for all Australians.

Land clearing typically involves the removal of vegetation by attaching a heavy chain between two bulldozers and dragging it across the land. This is often followed by burning to remove any trace of life. In Queensland, this is responsible for the death of tens of millions of native mammals, birds and reptiles every year. This includes many threatened and endangered species protected by law. Removing native vegetation also increases soil erosion and salinity, which in turn impacts the water quality, sediment and nutrient loads of river systems. Figures released by the Queensland Government this month showed that 40% of all clearing in 2015-16 occurred in Great Barrier Reef catchment areas, which represents an increase of 45% on the previous year. Land clearing has been identified as a major risk to the health of the Reef, while, conversely, stronger land clearing laws have been recognised by UNESCO and in the Queensland and Australian Government's 2050 Reef plan as vital for long term reef preservation and survival.

However, it is not just our wildlife and natural world that are under threat. As doctors, we are deeply concerned about the impact of land clearing and deforestation on human health.

People depend on forests and bushlands for survival. They purify the air we breathe and the water we drink; maintain the health of our soils so that we are able to grow nutritious foods; absorb and lessen the impacts of natural disasters like floods and cyclones; provide opportunities for recreation and ecotourism and make vital contributions to mental health and national and cultural identity. Importantly, they serve as a rich depository of medicinal plants with over half of all medicines in use today being derived from nature.

Of critical importance, our native forests and bushlands are also responsible for absorbing and storing carbon from the atmosphere. This protects against climate change, which has been recognised as the single greatest human health threat of this century. Estimates suggest that carbon pollution from land clearing and native forest destruction in Australia could be as high as 100 million tonnes per year. This is equal to almost 20% of Australia's total greenhouse gas emissions or about half of emissions from all of Australia's coal-fired power stations.

It is worth noting that as part of efforts to meet our Paris climate commitments, the Federal Government has directed $1.4 billion over recent years to vegetation projects which involve paying landholders to protect or restore vegetation and trees. However, by simultaneously failing to intervene and address State-Government regulated land clearing, it has ensured a cancellation out of any gains made from this expenditure in just one and a half years.

Land-clearing at the scale we are currently witnessing in Queensland can only be described as devastating. It not only shows reckless disregard for our wildlife and the Reef, but also a lack of understanding about the reliance of human health on intact ecosystems and a stable climate.

Both Federal and State governments must take strong action to prevent further destruction of our forests and bushlands. This should involve major reform of land-clearing regulations and investment in large-scale ecological restoration, which will probably require progressive financial agreements with participating landholders and businesses to create alternative revenue streams.

Ultimately, this is not just an environmental or agricultural issue, but also a fundamental issue of human health and wellbeing.