Improved mapping of South Australia's seagrass will help future recovery

Researchers at the University of Adelaide have been mapping large-scale seagrass cover and genus distribution on South Australia’s temperate coast.

Seagrasses are environmentally and economically important. They provide ecosystem services for humans including the provision of habitat for commercial species, protection of infrastructure from erosion and sea level rise, and improved water quality through nutrient uptake and stabilisation of sediments.

However the Environment Institute's Dr Kenneth Clarke says "increasing human populations have increased nutrient and sediment pollution to the sea, putting increasing strain on seagrasses and resulting in the loss of large areas of meadows."

This study improved methods of mapping seagrass cover and genus distribution along the coast of Adelaide, South Australia. Researchers used specialised cameras flown by Airborne Research Australia to collect ‘hyperspectral’ imagery and used special remote sensing methods.

More recent management has reduced or prevented those pollutants with researchers’ understanding evolving as they learn about different pollutants. Large studies focused on improving water quality are required to understand where to invest in future.

The mapping held a high accuracy rate of 98% and increased detail of the two dominant seagrass genera, Posidonia and Amphibolis. The data revealed that Amphibolis appeared to be more vulnerable to poor water quality, and was able to identify areas where Posidonia was recovering.

These results improve researchers understanding of seagrass ecology, and will help SA Water and other water management groups improve the future seawater quality in the South Australia’s environment.