India, Aug. 26 -- A comprehensive study of Great Barrier Reef catchments reveals that water quality has improved in bursts rather than steadily, often after shifts in rainfall, cyclones, land use and fertiliser practices.

Synthetic fertiliser use has dropped by up to half since its peak, yet sugarcane yields remain stable.

This indicates farmers are managing to cut pollution without sacrificing productivity.

Imagine a plume of brown sediment is washed off the land into Queensland rivers and carried out to sea. Here, it can settle on seagrass and inshore corals, potentially smothering them. River water often also carries nitrogen from fertiliser residue, which can fuel algal growth and damage coral health.

We have long known that poor ...