Scientific research published today on the impacts of poor water quality on some Great Barrier Reef corals shows why it's vital the Queensland Government passes new rules on farm pollution, the Australian Marine Conservation Society (AMCS) says.
The study, published in the journal Nature Ecology and Evolution, found corals in the central and southern sections of the reef would need improvements in water quality of between six and 17 per cent to keep their recovery rates in line with projected increases in coral bleaching.
Corals exposed to poor water quality were also more susceptible to disease and outbreaks of Crown of Thorns starfish, the study found.
Proposed Queensland government laws would phase out harmful farming practices that cause pollution and sediment to run into rivers and out into the reef.
Dr Lissa Schindler, AMCS Great Barrier Reef campaign manager, said: "We need to give the Great Barrier Reef the clean water it needs to recover, and this study shows that clearly. The Queensland Government's proposals to cut farm pollution need to be passed."
"What this study also says is that these levels of cuts to farm pollution won't be enough to save corals on outer reefs from the impacts of rising ocean temperatures caused by global warming.
"We have to make sure we are giving the reef the cleanest water we can, while at the same time stopping the digging up and burning of fossil fuels that drive the warming in the reef's waters."
Schindler said while the study found that corals in areas with poor water quality were more resistant to coral bleaching, due to the low level of light penetrating the turbid water, these corals had slower recovery rates and were more susceptible to disease and Crown of thorns starfish outbreaks.
The study, acknowledged that any marginal bleaching protection corals might get from poor water quality "are probably overwhelmed by the most extreme warming conditions" already seen during 2016 and 2017.
Schindler said it was also important to note the study did not consider any impacts of coral bleaching in the vast and once pristine northern sections of the reef that were hit hardest by extreme ocean temperatures in 2016 and 2017.
