Seagrass meadows are among the most efficient blue carbon sinks on earth, and if left undisturbed the carbon will stay locked away in sediments for thousands of years.
A recent study calculates that 5bn tonnes of carbon dioxide and other greenhouse gasses are stored at UNESCO’s 50 world heritage marine sites.
Three Australian sites – the Great Barrier Reef in Queensland, and Shark Bay and the Ningaloo Coast in Western Australia – lock away 2bn tonnes (almost 40%) of the blue carbon found across all the world heritage marine sites. This equates to four years of Australia’s annual greenhouse gas emissions.
These undisturbed world heritage marine sites are however under threat from development and climate change. As sea levels and temperatures rise, seagrass meadows die off and release stored carbon back into the atmosphere.
The report is co-authored by Dr. Oscar Serrano, a marine ecologist at Edith Cowan University in Western Australia, and a technical advisor to the Seagrass Ecosystem Services Project.