BY CATHRINE FORMOE AND KATHRINE WESTERN
“The amount of outside nutrients entering catchments of the river needed to be reduced quickly,” Swan River Trust Media Relations Manager Bridget Tombleson said.
These conditions can put stress on fish and other aquatic life if they persist.
“Low oxygen levels are caused by a breakdown of organic matter in the river’s sediments,” Ms Tombleson said.
“Salt water is heavier than fresh water and acts as a barrier, preventing oxygen from reaching the sediments.”
Better habitat for aquatic life
A new oxygenation program will provide specific plants that will be used in parts of the river to help increase oxygen levels.
Environmentalists within the trust are concerned about conditions advancing poorly in the river.
“The program would improve the health of the river and provide a better habitat for aquatic life. The presence of non-nutrient contaminants such as heavy metals, pesticides and pathogens placed further stress on the river,” Ms Tombleson said.
These contaminants cause algal blooms, which are formed when algae feed off nutrients in the river and can be harmful to aquatic life.