Jan 8 2021
Carlos Duarte, a prominent marine ecologist from King Abdullah University of Science and Technology (KAUST), explained that “Conserving the world’s oceans and coastal ecosystems is a no-regrets strategy posing huge benefits for people and planet.”
For 30 years, Duarte has headed the study into 'blue carbon' ecosystems that can help mitigate and adapt to climate change and these ecosystems include mangroves, sandy beaches, coasts, seagrasses, salt marshes and kelp forests.
Such ecosystems create several advantages; for instance, they serve as carbon sinks and provide other ecosystem services, like habitats for fisheries and several marine species; protectors from storms, floods and sea-level rise; regulators of coastal water quality; and sources of food and employment opportunities from tourism to transport.
Marine ecosystems can mitigate climate change by sequestering carbon from the air and oceans and subsequently storing it in the same marine ecosystems in the form of blue carbon.
Newly discovered options for sequestering blue carbon have demonstrated excellent potential—for instance, a previous study performed by Duarte and his collaborators has shown that different types of macroalgae are capable of storing more carbon than the other coastal plants.
Duarte and his collaborators have now estimated the potentials of China and Australia to preserve organic carbon in seagrasses, salt marshes, mangroves and vegetated coastal systems. Besides this, they have evaluated the distribution of macroalgae and brown seaweeds and their possible contribution to carbon storage.
Moreover, Duarte’s new study includes a strategy to reconstruct marine life by 2050 demonstrating, for instance, that restoring great whale stocks could sequester as high as 0.8 gigatons of carbon annually.
"Whales do more than store carbon in themselves. They move nutrients, accelerating productivity in the oceans and keeping them fertile. So as we rebuild the stocks of whales and other animals, the oceans will become more productive and capable of sequestering carbon. Improving the biosphere improves its capacity to achieve balance once more."
Carlos Duarte, Marine Ecologist, King Abdullah University of Science and Technology
But in spite of their significance, blue carbon ecosystems are facing a serious risk from marine pests, pollution, fishing, climate change and coastal urban development. For instance, nearly 50% of the mangrove ecosystems in the world have already been lost.
"If these communities of mangroves, seagrasses and saltmarshes are to provide vital ecosystem services, then we need to protect them and to take any opportunity to restore these habitats."
Carlos Duarte, Marine Ecologist, King Abdullah University of Science and Technology
Journal Reference:
Duarte, C. M., et al. (2020) Rebuilding marine life. Nature. doi.org/10.1038/s41586-020-2146-7.