Australia: Sea grass a potential solution in climate fight

Peter Hannam, Environment Editor, The Sydney Morning Herald 3 Dec 15;

How to make sea grass sexy?

That's the problem Carlos Duarte has been been trying to solve since at least 2009, when he and fellow marine researchers came up with the term "blue carbon" to describe the surprisingly large role the world's sea grasses, mangroves and salt bushes might play in tackling climate change.

"One hectare of healthy sea grass has the capacity of holding 15 times the carbon of one hectare of Amazonian rainforest," Professor Duarte, a marine ecologist at Saudi Arabia's King Abdullah University of Science and Technology, said. "Their role as a carbon sink has been neglected."

While mangrove and salt bushes can play key roles in protecting fragile coastlines from wave damage and promote biodiversity, it's the humble sea grass that provides the largest potential to store more carbon from the atmosphere.

"Firstly there are no forest fires in the water," Professor Duarte, who is also an adjunct professor at the University of WA, said. That compares with the hundred-year cycle - or less for Australia - between blazes that destroy many woodlands and release carbon back to the skies.

Secondly, if one plants three trees, in 20 years only one may survive, he said. By contrast, since sea grass clones, billions can grow over a similar period. This grass would be drawing down carbon and even raise sediment levels by as much as 5mm a year or faster than the rising sea-levels, he said.

Australian role

The value of coastal wetlands is gaining recognition in Australian government circles. Environment Minister Greg Hunt chaired an event at the Paris climate summit on Wednesday, outlining plans to protect the resource and quantify its carbon potential.

"We now need to find out how much blue carbon can be stored by these ecosystems and how this can contribute to emissions reductions," Mr Hunt said.

New research based at the University of Melbourne and funded by the federal government "will also aim to explore how coastal management activities impact on carbon emissions and identify high priority areas for restoration and conservation," he said.

The study will measure the existing carbon store, estimated now at about 2.5 billion tonnes of carbon, with the potential of using money from the $2.55 billion Emissions Reduction Fund to extend the resource "if accounting issues are resolved", he said.

Lessons learned will be shared with nations such as Indonesia, which has the largest share of the world's mangrove forests.

Justine Bell, a law lecturer in the University of Queensland attending the Paris talks as an observer, welcomed the focus on the coastal fringe, especially mangroves.

"People see them as eyesores that prevent them from accessing the coast," Dr Bell said. "They are absolutely critical" by biodiversity and coastal protection, she said.

Professor Duarte said the hosts of the Paris talks had shown an interest in working out how to include blue carbon in the climate agreement being thrashed out at the summit.

"They are looking for the best investments for small island states," he said, adding that France - as the world's biggest maritime state with its far-flung island colonies - may also have an interest of its own in the potential for blue carbon.

Fairfax Media is a partner of the United Nations Foundation


Australian research to unlock 'blue carbon'
AAP 9News 2 Dec 15;

The federal government is set to unveil new research into unlocking "blue carbon" from coastal areas, to offset carbon emissions, at major climate talks in Paris.

The research, to be undertaken by the National Environment Science Program, is part of Australia's aim to become one of the first countries to include blue carbon in its emissions inventory.

The government is also working on including marine carbon incentives as part of the $A2.55 billion emissions reduction fund, which pays Australian organisations to curb carbon pollution.

The research, which will be funded out of the NESP's $A23.9 million six-year funding, builds on previous work done by the CSIRO.

The project will be revealed at an Australian-led roundtable on day three of the United Nations climate change conference on Wednesday.

Research has already demonstrated that coastal ecosystems such as mangroves, seagrass beds and salt marshes can be much more effective than forests at sequestering carbon, the government said.

© AAP 2015