When a 1-in-100 year flood washed through the Coorong, it made the vital microbiome of this lagoon healthier

You might not give much thought to the sedimentary microbes of a lagoon. But these tiny microbes in the mud are vital to river ecosystems, quietly cycling nutrients and supporting the food web. Healthy microbes make for a healthy Coorong – and this unassuming lagoon is a key indicator for the health of the entire Murray-Darling Basin.

For decades, the Coorong has been in poor health. Low water flows have concentrated salt and an excess of nutrients. But in 2022, torrential rains on the east coast turned into a once-in-a-century flood, which swept down the Murray into the Coorong.

In our new research, we took the pulse of the Coorong’s microbiome after this huge flood and found the surging fresh water corrected microbial imbalances. The numbers of methane producing microbes fell while beneficial nutrient-eating bacteria grew. Populations of plants, animals and invertebrates boomed.

We can’t just wait for irregular floods – we have to find ways to ensure enough water is left in the river to cleanse the Coorong naturally.

Check out the latest article on the impact of flood waters on the Coorang’s microbiome and the it’s overall health:

When a 1-in-100 year flood washed through the Coorong, it made the vital microbiome of this lagoon healthier