New techniques to identify and reduce the sources of sediment blanketing parts of the Great Barrier Reef have landed Andrew Brooks and his team at Griffith University this year's Australian Museum Eureka Prize for environmental research.

The equivalent of some 900,000 dump-truck loads of dirt ends up on the reef each year. Blocking sunlight and covering corals, the sediment adds to challenges facing reefs that are already threatened by warming waters from climate change.

Associate Professor Brooks and his team studied the Normanby catchment in Cape York and the journey of fine sediment flowing into what was – before the past two summers of widespread coral bleaching – some of the most pristine areas of the reef.

Along with soil loss, the erosion hotspots are sources of nutrients that promote the crown of thorns starfish, another threat to corals. Other important ecosystems, such as sea grasses, are also adversely affected by the run-off.