Australia pledged half a billion dollars to restore and protect the Great Barrier Reef Sunday in what it said would be a gamechanger for the embattled natural wonder. The World Heritage-listed site is currently Under threat from coral bleaching, pollution and climate change. With its heavy use of coal-fired power and relatively small population, Australia is considered one of the world's worst per-capita greenhouse gas polluters. Canberra has previously committed more than Aus$2.0 billion to protect the site over the next decade, but has been criticised for backing a huge coal project by Indian mining giant Adani nearby.