A study out of Western Australia has attempted to place a monetary value on two water-based ecosystems to better understand their myriad values to the environment and as sources of carbon sequestration.
The Blue Carbon Lab, under Deakin University in Victoria, calls this a “first pass evaluation” to better understand the economic value of wetlands. The five-author report was funded by Conservation Volunteers Australia.
It has found particular fresh and salt water systems offer billions of dollars of value in addition to their abilities to sequester CO2 and nitrogen.
Ecosystem services are not the same as a carbon project, where a quantifiable amount of emissions reduction is turned into a tradable commodity, but rather serve as the “connecting concept between ecosystem assets and the production and consumption activity of businesses, households, and governments”, the paper published late last week read.
The paper looked at two coastal and two freshwater wetlands, assessing “specifically carbon and nitrogen storage and sequestration as well as water quality improvement through nitrogen removal, and coastal hazard mitigation”.
“Wetlands can store up to four times more carbon and sequester up to 40 times faster than any other ecosystem,” the authors wrote.
Much of the work undertaken as part of the environmental review used datasets and 43 studies, of which 60% were studies of seagrass ecosystems and 67% quantifying carbon stocks.
Ecosystem services benefit surrounding businesses as much as the environment, the authors said, from tangible goods such as timber and fish stocks to the less immediately quantifiable like water purification, global climate regulation, and recreation-related services.
“Commonly, these types of services are supplied to communities outside markets. The focus of accounting for ecosystem services is to provide a clear description of the range of these services, the spatial heterogeneity of their delivery, and the local to global beneficiaries of these services,” it said.
It used the data to infer possible changes in these areas since European settlement.
Wetlands in the Cane River provide just under 2,800 tonnes of CO2e per year of carbon sequestration and another 231 tonnes of nitrogen sequestration with an estimated ecosystem service value of A$1.15 billion ($750 million) per annum, with $167,000 of that in coastal hazard mitigation, it found.
“The freshwater wetlands of Beeliar Regional Park provide 11,682 tonnes CO2e of carbon sequestration and 37 tonnes of nitrogen sequestration with a combined value of A$37.1 million. Forrestdale Lake Nature Reserve freshwater wetlands provide ecosystem services valued at A$5.9 million including sequestration of 1,874 tonnes CO2e per annum and 6 tonnes of nitrogen.”
“Mangroves, saltmarshes, and tidal mudflats in the Cossack region provide 3,133 tonnes CO2e per annum of carbon sequestration and 247 tonnes of nitrogen sequestration services with a total ecosystem service value of AU$1.21 billion per year,” it said.
“Further studies and local datasets from WA are needed to improve our capacity to predict and understand the value of wetlands in the state,” it added, saying the “first pass” work shows the benefits of wetlands but highlights more needs to be done.
By Helen Clark – helen@carbon-pulse.com
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