Preliminary results from our Queensland Blue program reveal coastal wetlands from the Great Barrier Reef catchment hold 11 million tonnes of carbon stocks.
Queensland’s Great Barrier Reef (GBR) is widely known for the beauty and diversity of its corals and fishes. However, research funded by the QLD’s Land Restoration Fund Pilot Project Grant is putting all the attention in the coastal wetlands of the catchment.
Coastal wetlands – mangroves, tidal marshes, and seagrasses – are collectively known as ‘Blue Carbon’ ecosystems. They act as as natural sinks of carbon, effectively reducing atmospheric carbon concentrations that contribute to climate change.
The Blue Carbon Lab is assessing the blue carbon potential within the GBR catchment, including mapping of blue carbon stocks and sequestration rates. The goal is to answer two key questions underpinning investment in blue carbon from the Land Restoration Fund context: how big is the opportunity for blue carbon in Queensland and where to act?
Spatial analysis of the mangrove forests and seagrass meadows within the GBR catchment- along with data on soil carbon stocks and accretion rates – has revealed the region holds a blue carbon stock of over 111 million tonnes, which is equivalent to the annual emissions of ~87 million cars.
Distribution of blue carbon stocks (tonnes per hectare) across the GBR catchment at 15 m resolution. Estimates are conservative as tidal marshes were not included due to lack of data.
Results also showed that six Local Government Areas (LGA) hold almost 70% of all the blue carbon in the GBR catchment. The top six blue carbon hotspots include the Cook Shire, Livingstone Shire, Gladstone Regional, Burdekin Shire, Isaac Regional and Whitsunday Regional.
The program’s lead scientist Dr Micheli Duarte de Paula Costa is currently modelling blue carbon accumulation under different management scenarios (e.g. carbon accumulated in the soil when blue carbon is restored/conserved or carbon lost if habitat is disturbed). This analysis will then be used to reveal the scale of blue carbon opportunities within the Great Barrier Reef catchment.
These spatially-explicit results will guide wetland restoration efforts in Queensland and inform future strategies to incorporate coastal blue carbon within CO2 mitigation strategies, thereby helping to mitigate climate and enhancing ecosystem services (eg. coastal protection, water quality, economic growth, community well-being).
*This research is led by the Blue Carbon Lab in partnership with The University of Queensland, James Cook University, Qantas, HSBC, CSIRO, Department of the Environment and Energy, NQ Dry Tropics, Great Barrier Reef Foundation and Greencollar.