Blue carbon could be Shark Bay gold

Blue carbon could be Shark Bay gold

A researcher from the University of Western Australia says the extensive seagrass meadows underneath WA’s World-Heritage-listed Shark Bay form one of the world’s largest ‘blue carbon’ sinks.

Published: 29 August 2011

http://www.ecosmagazine.com/?paper=EC11021

Seagrass meadows at Shark Bay, WA. Researchers are investigating the value of seagrass habitats in sequestering carbon. (Image credit: Gary Kendrick/UWA)

Professor Jim Fourqurean calculates the value of the sequestered carbon at more than eight billion dollars, using the carbon price proposed by the Federal Government of $23 per tonne.

‘When you think of carbon storage and ecosystems, you generally think of canopies of trees, so a lot of attention has gone into forests,’ says Professor Fourqurean.

‘But there is as much carbon on average stored in a seagrass meadow as there is stored in a forest.

‘There are about 4000 square kilometres (400 000 hectares) of seagrasses in the bay, which places it among the largest seagrass meadows that have been recorded in the world.

Professor Fourqurean has calculated the amount of carbon dioxide stored in the seagrass meadows as being, on average, 884 tonnes CO2 equivalents per hectare.

‘So if you multiply that 884 tonnes of CO2 by 400 000 hectares of seagrass, you get about 350 million tonnes of carbon stored in the seagrass meadows underneath Shark Bay,’ he says.

Professor Fourqurean is involved in the global Blue Carbon initiative, a relatively new international scientific network aiming to preserve seagrass habitats as a climate mitigation strategy.

Blue carbon researchers are also exploring the monetary value of the carbon in seagrass meadows as part of a possible offset scheme – which could benefit developing countries, in particular, in protecting seagrass and mangrove habitat.

‘One of the reasons we're doing that is seagrasses are disappearing at a rate faster than the rate at which coral reefs are disappearing and the tropical forests are disappearing,’ says Professor Fourqurean.

‘It's not a simple policy issue to solve, because a lot of marine environments don't have a single owner.

‘The reason seagrasses are disappearing is not because of land conversion, like tropical forests; usually, seagrasses are lost because of poor watershed management practices and declining water quality near shore.’

Shark Bay's seagrass meadows are recognised as a vital habitat for dugongs and sea turtles, and as a food source for the Shark Bay prawn and scallop fisheries.

Seagrass meadows promoted as carbon sink

Seagrass meadows promoted as carbon sink

Updated August 23, 2011 13:22:13

http://www.abc.net.au/news/2011-08-23/shark-bay-seagrass-carbon-link/2851630

Jim Fourqurean dives near Shark Bay to research the extensive seagrass meadows

A new study has revealed how seagrass meadows off Western Australia's coast could help mitigate climate change.

Jim Fourqurean conducted research on the extensive seagrass meadows at Shark Bay with the aim of showing that such reserves store as much carbon dioxide as trees.

Shark Bay's seagrass reserves stretch for 400,000 hectares, making it one of the largest in the world.

Professor Fourqurean calculated that the meadows would be worth more than $8 billion if priced under the Federal Government's proposed carbon tax.

He hopes the study will encourage the Government to consider including seagrass as part of a carbon offset scheme.

Shark Bay seagrass 'potentially an $8 billion carbon sink'

Shark Bay seagrass 'potentially an $8 billion carbon sink'

Monday, 22 August 2011

http://www.news.uwa.edu.au/201108223834/business-and-industry/shark-bay-seagrass-potentially-8-billion-carbon-sink

Shark Bay's extensive seagrass meadows act as a massive carbon sink which stores more than eight billion dollars' worth of carbon dioxide if valued according to the Federal Government's proposed carbon price.

That's the figure calculated by researcher Professor Jim Fourqurean who is part of a new global initiative aimed at utilising seagrass meadows to help mitigate climate change.

Professor Fourqurean has been researching the seagrasses of Shark Bay - a World Heritage area - as part of his work with The University of Western Australia's Oceans Institute, where he has been the Gledden Visiting Fellow.

"Shark Bay's seagrass meadows are a vital habitat for dugongs and sea turtles, and they provide the food for fisheries such as the Shark Bay prawn and scallop fisheries," he said.

"There are about 4,000 square kilometres (400,000 hectares) of seagrasses in the bay which places it among the largest seagrass meadows that have been recorded in the world.

"When you think of carbon storage and ecosystems, you generally think of canopies of trees, so a lot of attention has gone into forests.

"But there is as much carbon on average stored in a seagrass meadow as there is stored in a forest. It's not stored as a living biomass; it's stored as soil carbon."

Professor Fourqurean has calculated the amount of carbon dioxide stored in the seagrass meadows, as part of work involving his Oceans Institute colleagues Winthrop Professor Gary Kendrick and Emeritus Professor Di Walker who are undertaking a Caring for Our Country project funded by the Australian Government.

"My average number is 884 tonnes CO2 equivalents per hectare," he says.

"So if you multiply that 884 tonnes of CO2 by 400,000 hectares of seagrass, you get about 350 million tonnes of carbon stored in the seagrass meadows underneath Shark Bay."

The Federal Government proposes introducing a carbon tax which prices carbon at $23 per tonne, which means the seagrass carbon offset is potentially worth a considerable amount.

"So about $8.13 billion of carbon is stored in the seagrass meadows of Shark Bay - if that carbon had a price on it in the world market," he says.

Professor Fourqurean is involved in the Blue Carbon initiative, along with UWA Oceans Institute Director Professor Carlos Duarte. The initiative is a relatively new international scientific body aiming to preserve seagrass habitats as a climate mitigation strategy. Part of the work is exploring the monetary value of the carbon in seagrass meadows as part of a possible offset scheme.

"One of the reasons we're doing that is seagrasses are disappearing at a rate faster than the rate at which coral reefs are disappearing and the tropical forests are disappearing," he says.

"It's not a simple policy issue to solve, because a lot of marine environments don't have a single owner.

"And the reason seagrasses are disappearing is not because of land conversion, like tropical forests are being lost. Usually seagrasses are lost because of poor watershed management practices and declining water quality near shore.

"So trying to figure out how to capture carbon credits to pay for the maintenance and the reduction of the loss - or maybe even the creation of new seagrass meadows in order to increase the carbon storage - is conceptually difficult."