Major new threat to Great Barrier Reef identified   

New Daily
Oct 9 2023

Scientists have identified a major new threat to the Great Barrier Reef – invisible groundwater flows delivering nutrients at harmful levels.

It’s long been known that nutrient-rich river water is a major cause of poor water quality on the reef.

But a landmark study has shown groundwater that seeps from the land into the sea, below the water line, is a far bigger source of nutrients, including problematic nitrogen and phosphorous, which are heavily used in fertiliser.

Excessive nutrients affect reef health in range of ways, including fuelling harmful algal blooms that can block sunlight, reduce corals’ resilience to bleaching and affect coral diversity.

Scientists say it’s time to rethink protection strategies, which up until now have been heavily focused on addressing nutrient loads in river water.

Their study showed groundwater discharge was ten to 15 times greater than river inputs.

Groundwater discharge accounted for about a third of new nitrogen entering the reef – almost twice what river water delivers.

It also accounted for two thirds of new phosphorous inputs – about six times what’s in river water.

“We need to have a good discussion about where our management efforts are taking place,” says study leader Douglas Tait, from Southern Cross University.

“There are significant amount of resources and time and effort being spent on managing river water inputs.

“What this study is pointing at is that we need to be looking at how we manage the groundwater as well.”

An obvious place to start is looking at better managing what ends up in groundwater – the water that’s stored and moves through geological formations below the land surface.

More work is also needed to identify and manage any discharge hotspots. That would open up the prospect of using seaweed, for example, which needs nitrogen and phosphorous to grow.

“Our understanding and ability to manage the sources of nutrients is pivotal in preserving the reef for generations to come,” Dr Tait said.

The federal government’s reef protection plan says sediment and nutrient pollution from agricultural run-off, and to a lesser extent urban and industrial activities, are the main sources of poor water quality.

The plan is central to Australia’s efforts to prevent the reef from being listed as a World Heritage site in danger.

The World Heritage Committee in September gave Australia more time to demonstrate it is addressing major threats, with the government due to provide a progress report in early 2024.

The peer-reviewed research has been published in the journal Environmental Science and Technology.

The work was supported with funding from the Australian Research Council, the Herman Slade Foundation and the Great Barrier Reef Foundation.

Those scientists you unjustly disparage cultivated corals, spread their motile young all over the GBR.

Wash your mouth out with soap, idiot!

Jovial Monk wrote on Oct 9^th, 2023 at 8:50pm:



What coral have forgotten how to spawn naturally. 

Jovial Monk wrote on Oct 10^th, 2023 at 6:27am:



But we have zombie coral, because Terry Hughes said back in 2016 it was dead.

"Two-thirds of the corals in the northern part of the Great Barrier Reef have died in the reef’s worst-ever bleaching event, according to our latest underwater surveys. "

https://theconversation.com/how-much-coral-has-died-in-the-great-barrier-reefs-w...

And yet now it is back to at least those levels.

"Last week saw the yearly spectacle of the Great Barrier Reef’s coral spawning event! The time of year where all corals get busy making babies happens usually just once a year and this year was special as always but for more reasons than normal. Researchers and Marine Biologists from around the world jumped into the waters of the biggest reef in the world to witness this spectacle and, as always, ground breaking science occurred…"

https://www.marinediscoveries.com.au/blog/coral-spawning-2022

Edit: "In 2022, widespread recovery has led to the highest coral cover recorded by the LTMP in the Northern and Central GBR, largely
due to increases in the fast-growing Acropora corals, which are the dominant group of corals on the GBR and have been largely
responsible previous changes in hard coral cover."

https://www.aims.gov.au/sites/default/files/2022-08/AIMS_LTMP_Report_on%20GBR_co...