Earlier this year, a record-breaking investment to protect the Great Barrier Reef was announced: a $500 million pledge to help combat the pollution, overfishing and warming waters that currently threaten the largest living structure on earth.

Sorry, this video has expired Environment minister Josh Frydenberg announces 'largest investment in reef restoration'

Australia's commitment to the reef is well known, but ocean health goes beyond the preservation of this famous marine ecosystem.

For a start, our oceans are a major heat and carbon sink — they capture the excess heat and carbon causing global warming, helping to regulate the earth's temperature. They supply half the world's oxygen, and are home to millions of marine species which provide food and a livelihood to a billion people.

In Australia alone, it is estimated that marine industries will contribute around $100 billion per year to the country's economy by 2025.

But our oceans are under intense pressure to keep up these vital functions. Marine wildlife is estimated to have halved in the last 45 years, and our oceans are about 30 per cent more acidic than before the industrial revolution.

As a wealthy island nation, with the third largest marine jurisdiction on earth, Australia is in a unique position to help.

Unlocking the secrets of sustainable fishing

Unsustainable fisheries and damage of marine habitats are two of the main drivers of poor ocean health in the Pacific region. Fishing and the development of aquaculture, however, are critical for the food security and livelihoods of small island nations. Less fishing is therefore not the answer, safer and more sustainable fishing is.

Together with WorldFish, a CGIAR Research Center, the Australian Centre for International Agricultural Research (ACIAR) has been working to assist fishers to sustainably manage their coastal fisheries and protect their reef habitat.

"Fish aggregating devices" (or FADs) are small man-made structures that float near the coast and attract oceanic fish such as tuna and mackerel. Decades of research have led to the most effective design of FADs to withstand strong currents and deep waters.

Fishermen in Timor-Leste and the Solomon Islands are now reaping the rewards. They are able to capture more fish than ever before, without disturbing their delicate natural habitats — the fish now come to them.

Hand in hand with the introduction of such fishing innovations, the University of Wollongong (UoW), co-funded by ACIAR and the Department of Foreign Affairs and Trade, is working with communities across the Pacific to help them to restore and better manage their delicate coastal fisheries.

The key to success has been to bring communities and fisheries agencies together. UoW is assisting them to develop co-management practices that allow them both to benefit, and take into account the complex social and ecological systems that influence fisheries sustainability.

Such community-based approaches promise to play a central role in securing the benefits to Pacific coastal communities that flow from coastal resources.

If the water temperature doesn't drop after bleaching, corals starve and die, and get overgrown with algae. ( Supplied: Great Barrier Reef Marine Park Authority )

Protecting coral reefs worldwide

In the Philippines, coral reefs have suffered intense damage from dynamite fishing, a practice which still persists. Cheap explosives are used to stun fish for capture, at the same time destroying the coral reefs where they live.

Reefs protect coastline communities from tropical storms, as well as being a vital source of nutrients for marine wildlife.

Australian scientists have discovered that a process akin to IVF for humans can work for coral, encouraging their reproduction in laboratories. The larvae can then be placed back into the ocean to stimulate restoration of damaged reefs.

This work is carried out by ACIAR and Southern Cross University and has major implications for reefs not only in the Pacific region but for bringing reefs back to life worldwide.

Helping coastlines to capture carbon

The Pacific region is also rich in vegetative coastal habitats, such as mangroves and tidal marshes. Indonesia alone has three million hectares of mangrove forests lining its 95,000-kilometer coastline — about 23 per cent of all mangroves in the world.

In 2016 coral loss was highest in the northern section of the reef where the heatwave was strongest. ( Supplied: ARC Centre of Excellence for Coral Reef Studies )

Mangroves are thought to have up to 50 times the power of other ecosystems for capturing carbon.

The more excess carbon we can suck from the atmosphere, the less the whole world will suffer from rising temperatures that exacerbate the deadly bush fires and droughts we continue to witness.

Australia has therefore become a founding member of the international partnership for "blue carbon", a term coined to describe these marine habitats capable of extensive carbon capture.

Efforts are now underway to replant 60,000 hectares of degraded mangroves each year in Indonesia, involving up to 200,000 farmers.

The woodchip, pulp and paper industry, which utilizes mangrove wood, is also getting involved.

Indonesian company PT Kandelia Alam actively preserves one third of their newly acquired concession in West Kalimantan, and has even started ecotours to show off the irawaddy dolphins and proboscis monkeys that reside in the protected areas.

The Great Barrier Reef may continue to grab the most headlines, but protecting ocean health on a global scale is just as vital. This World Oceans Day is a reminder of their importance and the need to ensure that Australia's and CGIAR's world class research in this area gets the support it deserves.

Mellissa Wood is the general manager of global programs for ACIAR, and Elwyn Grainger-Jones is executive director of the CGIAR System Organization.