'Now or never' to save Barrier Reef: scientists

Australia's Great Barrier Reef could be beyond saving in five years without "now or never" funding to improve water quality as climate change ravages the World Heritage-listed site, scientists warned Thursday.

The world's biggest coral reef ecosystem is under pressure from not only climate change, but farming run-off, development and the coral-eating crown-of-thorns starfish.

The biodiverse side off the Queensland state coast is also suffering its worst bleaching in recorded history with 93 percent of corals affected due to warming sea temperatures.

"The current management regime for catchment pollutant run-off and climate change is clearly inadequate to prevent further decline," James Cook University researchers Jon Brodie and Richard Pearson wrote in a paper published in the Estuarine, Coastal and Shelf Science journal.

They added in a statement Thursday that without government funding of Aus$10 billion (US$7.2 billion) over the next decade to improve water quality, "the Great Barrier Reef will be in a terminal condition within five years".

"What's happening is we're seeing climate change ramp up much more quickly than most scientists... believed," Bodie told AFP.

"One thing we can do is fixing water quality for the reef. For water quality management, I think it is now or never because we have to do the management now to give us some resilience against climate change."

Bodie said the poor water quality was due mainly to sediment from grazing lands, which causes water to be cloudy and affects the growth of coral and seagrass.

Fertiliser run-off, particularly nitrogen, from the sugarcane industry was also causing crown of thorns outbreaks as the nutrients were fuelling the growth of the predatory coral-feeding starfish, he added.

The funding would go on programmes such as planting trees along stream banks to stop erosion, the scientists said.

A spokesman for Environment Minister Greg Hunt said the government was doing "more than ever before" to protect the reef for future generations.

"Through our Aus$210 million Reef Trust, we are investing in projects that directly improve water quality in the Great Barrier Reef. This is part of a broader Aus$2 billion investment by Australian governments to protect the reef," he said.

According to a 2013 Deloitte Access Economics study commissioned by the government, the reef contributes around Aus$6.0 billion annually to the economy, mainly through tourism.