A new study says that a global agreement on climate change will come too late to save the majority of the world's coral reefs. The research comes as the Queensland state government announces a new multi-million dollar plan to protect the Great Barrier Reef from agricultural pollution. From Sydney, Phil Mercer reports.

The study, from Stanford University in the United States, makes gloomy assessments about the future health of the world's coral reefs.

It finds that carbon dioxide emissions are making seawater so acidic that coral reefs could begin to disintegrate within a few decades.

The report states that even ambitious plans to stabilize greenhouse gas emissions, thought by many to be the main cause of a warming climate, will not be enough to save the reefs.

About a third of carbon emissions is soaked up by the world's oceans, where it combines with seawater to form carbonic acid.

The research comes as the Queensland state government in Australia announces a new plan to protect the Great Barrier Reef from agricultural pollution.

The iconic reef is being damaged by pesticides and sediment from farms that seep into waterways.
The Queensland government is to spend an extra $30 million to reduce this hazardous run-off.  Farmers also will face tougher environmental regulations.

Queensland Premier Anna Bligh says that man-made threats present serious challenges to the reef, which is a world heritage site.

"We know that there are many contributing factors to the water quality of the reef," she said.  "We are already addressing a number of those activities, particularly around increased population levels, sewerage treatment, etc.  But what the science is telling us is that the highest levels of damaging chemicals and nutrients are in those areas that have intense farming activity."

Coral reefs are common in warm southern and equatorial oceans, and provide homes and feeding grounds for thousands of species, including fish that are important to the diets of millions of people in the developing world.  In Asia, Indonesia, Indonesia and Papua New Guinea are among the many countries that rely on reefs to provide food and to draw in tourists eager to explore the ocean.

Environmental groups welcome the Queensland plan to protect the Great Barrier Reef.

Farmers, however, argue they have already taken significant steps to stop the spread of pollutants from their land.

The Great Barrier Reef stretches for more than 2,000 kilometers along Australia's northeast coast.  It is not only an ecological marvel, but generates billions of dollars for Australia's tourism industry, drawing in thousands of scuba divers and others who want to see the marine animals that live along the reef.