Antinuclear

Scientists working together with indigenous land-managers have reduced Australia’s greenhouse gas emissions by half a million tonnes. IMPROVING FIRE MANAGEMENT in the tropical savannah of northern Australia has reduced greenhouse gas emissions by more than 500,000 tonnes over the past year.

By reintroducing traditional fire knowledge and practices, local land managers have benefited through the sale of carbon credits, as well as helping the environment.

“Methane and nitrous oxide emissions from savannah burning represent about three per cent of Australia’s total greenhouse gas emissions,” said the CSIRO’s Dr Garry Cook at the 2014 annual conference of the Ecological Society of Australia in Alice Springs in September.

“Since European settlement, fires in the north have increased in size and severity. This has threatened biodiversity as well as increased greenhouse gas emissions,” he said.

Australia’s tropical savannah landscape is enormous — it covers an area of some 1.9 million square kilometres, or about one quarter of the entire continent. The landscape is mainly forests and woodlands consisting of wide fields of grass with scattered eucalypt trees.

The savannah stretches from Rockhampton on the Queensland coast up to the tip of Cape York and across to the Kimberley region of Western Australia on the Indian Ocean.

Frequent fires are a characteristic of the landscape, and the vast majority are deliberately lit without any authorisation. Tens of thousands of square kilometres burn every year during the northern dry season.

Many local Aboriginal communities have retained their traditional fire knowledge, and these communities hold deep aspirations to fulfil long-held cultural obligations regarding country. Dr Cook said the Commonwealth’s Carbon Farming Initiative provided the impetus to restore traditional fire management practices on aboriginal homelands, combining modern environmental and fire science with traditional mosaic burning practices.

“In order to reduce greenhouse gas emissions under the methodology, land managers need to burn early in the dry season to protect the landscape from the more intense fires that would otherwise occur later in the dry season,” he said.

“Early dry-season fires are generally low in intensity; they trickle through the landscape and burn only some of the fuel, creating a network of burnt firebreaks. These stop the late dry-season fires sweeping through large areas and releasing large amounts of methane and nitrous oxide.

“Most savannahs burn on average once in every two to four years, in the late dry season, and it’s these fires that produce between three and four per cent of Australia’s accountable greenhouse emissions. The methodology helps reduce these emissions by using low-intensity, patchy early dry-season fires to reduce the overall fire frequency and proportion of late dry-season fires, which tend to be much larger and more intense,” Dr Cook said.

The savannah burning methodology for reducing methane and nitrous oxide emissions was developed by a team from CSIRO, the Charles Darwin University’s Centre for Bushfire Research, the Northern Australia Indigenous Land and Sea Management Alliance, and Aboriginal landowners and rangers in northern Australia.

Dr Cook said, “It’s lovely to see science being applied to improve land management in that part of the world: we’re talking very remote country, very limited resources for land management, and very sparse populations. It’s had a great impact.”