The federal government is daring the World Heritage Committee to put the Great Barrier Reef on its endangered list by approving a huge coal port near Bowen, the Australian Greens warn.
Environment Minister Greg Hunt has given the Abbot Point project the go-ahead, subject to what he says are strict environmental conditions.
He has also approved Arrow Energy's gas project on Curtis Island in central Queensland and a transmission pipeline to the island.
Greens senator Larissa Waters says the Abbot Point approval is an environmentally disastrous decision which threatens the reef, the world's climate and Queensland's economic stability as climate change impacts.
"The Abbott government is doing exactly what the World Heritage Committee told us not to do," she told ABC radio on Wednesday.
The federal approval limits dredging to 1.3 million cubic metres of sediment per year, down from 38 million cubic metres proposed under Labor.
As well dredging can only be conducted in a limited window between March 1 and June 30.
Mr Hunt defended his decision saying there would be permanent improvements to the Burdekin and the Don Rivers.
That would result in a net benefit to the quality of the water in the reef.
"This is a significant step towards improving and protecting the Marine Park for future generations," he said.
Environmental campaigners dressed as Nemo and turtles will protest against the approval in Brisbane's CBD on Wednesday morning.
Greenpeace, Friends of the Earth and the Australian Marine Conservation Society (AMCS) are behind a demonstration in which masked look-a-likes of Greg Hunt, Tony Abbott and coal barons will be covered in dredged mud.
"This is something the government could have stopped by simply saying no," AMCS marine ecologist Dr Lissa Schindler told AAP.
"The state and federal governments have both made it very clear where their priorities lie regarding the Barrier Reef, but the Australian people feel very strongly about its protection.
"Perhaps we should send Greg Hunt the Wikipedia page on dredging so he can read what it's all about."
