To better protect the Great Barrier Reef, Australia must also pay attention to how to better use and maintain the mainland to prevent further damage to these great ocean treasures.

When the watersheds are deforested, more sediment washes down into the ocean, making for poor water quality.  That weakens corals; they can’t deal with thermal stress as well, and they don't recover from bleaching events.  And that leads to a breakdown of the reef ecosystem.

The University of Western Australia study looked at four watersheds in Madagascar, which sits above the water line next to coral reefs similar to our Great Barrier Reef.  The watersheds mimic most of the world's coral reef climate and a range of different land uses.

“The findings are very relevant for Australia since intense land use and past deforestation have transformed the river catchments tremendously and are seen as a major threat to coral reefs in the Great Barrier Reef and elsewhere,” said Dr. Jens Zinke, of UWA's Oceans Institute.

The study suggests that resources spent reforesting and restoring the land would also preserve the coral reef ecosystems at the coast.