A Griffith University research team led by Mullumbimby-based scientist Associate Professor Andrew Brooks has taken out a prestigious 2017 Australian Museum Eureka Prize for their work trying to save the Great Barrier Reef.
The team, which comprises scientists from the Griffith Centre for Coastal Management and the Australian Rivers Institute, has discovered what may be Australia’s best chance of doing something timely to help the reef, transforming how sediment sources are identified and targeted.
As winners of the NSW Office of Environment and Heritage Eureka Prize for Environmental Research, the team members were recognised at the Awards Dinner at Sydney Town Hall last Wednesday night (August 30).
900,000 dump trucks of dirt
Sediment and associated nutrient run-off is one of the most significant threats to the natural wonder next to climate change.
About 900,000 dump trucks of dirt flows out to the reef on average each year.
In the first study of its kind, scientists traced the path of fine sediment from its origin in the Normanby catchment in Cape York – the fourth largest catchment draining to the reef – through to its ultimate destination in the northern reef lagoon.
Sunlight limitation caused by dirty water in flood plumes can kill coral and seagrass. The effect extends in the weeks and months following floods as with the sediment is remobilised by wind and currents. Sediment also contains nutrients, which promote the growth of the damaging Crown of Thorn Starfish colonies.
The work, funded through the Australian Government’s Reef Rescue program, set out to build a catchment model from the ground up. Associate Professor Brooks said this was the first example of such a model being built for a reef catchment.
The study combined a range of innovative field and remote sensing techniques to quantify sediment sources and sinks across this 24,500 square kilometre catchment: an area slightly smaller than Belgium, much of which is only accessible by helicopter.
‘This research completely changed our understanding of where the sediment was coming from,’ he said.
Gully erosion
‘We now know that aggregations of gully erosion – or gully hotspots – concentrated in a few per cent of a catchment’s land area, can be the source of 40 per cent of its sediment output.
‘Now we can much more effectively target our rehabilitation resources and get on with the urgent task of improving reef water quality.’
Associate Professor Brooks said their understanding of how management actions needed to be targeted had also been completely reversed.
‘Our research also showed how such gullies can be remediated, and what is required in terms of resources and effort to achieve the required sediment and nutrient reduction targets for the Great Barrier Reef,’ he said.
Evidence-based approach
‘It’s important to realise that our evidence-based rehabilitation approach will do much more than improve water quality on the reef – critical as that is. It’s also vital to the future health of the rivers and land throughout the Barrier Reef catchments, and beyond.’
He added that the team’s research findings have directly influenced $60 million of government funding focused on addressing gully erosion. He said the new investment was a critical part of the race to improve water quality and boost the reef’s resilience to bounce back from Crown of Thorn Starfish and the bleaching and cyclone events associated with global warming.
Senior Deputy Vice Chancellor Professor Ned Pankhurst congratulated the team on their win and remarkable research efforts.
‘The work Griffith University is doing to protect one of the natural wonders in the world shows our strengths as leaders in the environmental research field, working with industry and government to ensure our work delivers meaningful impact and results,’ he said.
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