China's economic boom has seen its coral reefs shrink by at least 80 percent over the past 30 years, a joint Australian study found, with researchers describing "grim" levels of damage and loss.

Scientists from the Australian Research Council Center of Excellence for Coral Reef Studies and the South China Sea Institute of Oceanology said their survey of mainland China and South China Sea reefs showed alarming degradation.

"We found that coral abundance has declined by at least 80 percent over the past 30 years on coastal fringing reefs along the Chinese mainland and adjoining Hainan Island," said the study, published in the latest edition of the journal Conservation Biology.