AIMS takes aim at Great Barrier Reef management

Government plans for improving water quality on the Great Barrier Reef will not meet their intended targets, according to a new science paper titled Towards protecting the Great Barrier Reef from land-based pollution
published yesterday in Global Change Biology.

New agricultural products and land uses, and the restoration of coastal rivers and wetlands to improve the ability of catchments to absorb pollutants before they reach the reef, are among options discussed in the paper.

Poor marine water quality — largely the result of excess sediment, nitrogen, phosphorus and pesticides flowing from the land into the GBR lagoon — has a significant impact on reef health, as lead author Dr Frederieke Kroon from the Australian Institute of Marine Science (AIMS), explains.

"Fine sediments reduce light availability for corals and seagrasses; nitrogen discharge promotes the growth of algae, which is associated with outbreaks of the coral-eating Crown-of-thorns starfish; and exposure to herbicides can reduce the productivity of seagrass in coastal and inshore meadows affecting dugong and turtle populations."

Despite significant public investment to date, and more than 10 years of dedicated plans to improve reef water quality, the authors note that recent Great Barrier Reef Report Cards demonstrate only modest changes in agricultural management practices — significant drivers of water quality in the rivers and coastal waters of the GBR.

"Water quality has been improved by voluntary actions of land holders and by industry-supported incentives to adopt agricultural best management practice," says co-author Dr Britta Schaffelke. "Our review suggests that, based on overseas experiences, combining voluntary approaches with more effective legislation, regulation and assistance programs would accelerate the uptake of improved practices."

"However, if we want to improve water quality enough to meet the intended targets, we will have to move beyond traditional agricultural systems. This may include new agricultural products and land uses, and the implementation of comprehensive programs to restore river flows, wetlands and riparian zones in coastal catchments," says Dr Kroon.

The new paper Towards protecting the Great Barrier Reef from land-based pollution by Frederieke Kroon, Peter Thorburn, Britta Schaffelke and Stuart Whitten appears in the journal Global Change Biology. The ABC ran a news item, interviewed the authors and the Minister for the Environment, Greg Hunt, on the Sunday April 3 about this issue.