NEW YORK, July 3 — Although relatively little-known to the general public, so-called “blue carbon ecosystems” are powerful carbon sinks for the planet. The term encompasses several species of aquatic plants which, through photosynthesis, capture carbon in the atmosphere and store it thanks to their roots.
From seagrass beds to mangroves and salt marshes, these aquatic ecosystems, commonly referred to as “blue carbon ecosystems” (and in some cases “blue forests”) play a key role in capturing carbon from greenhouse gas emissions. According to Unesco estimates, despite covering less than 1 per cent of the seafloor, they account for more than 50 per cent of the carbon stored in the ocean, and are “among the most intensive carbon sinks in the biosphere.”
At the beginning of 2024, Japan became the first country to include the carbon sequestered by marine algae in its national emissions inventory, as provided for by United Nations Framework Convention on Climate Change (UNFCCC). According to the Japan Times, “blue carbon ecosystems reportedly sequestered 0.03 per cent of Japan’s annual emissions in the year through March 2023.”
But these ecosystems, like the planet’s other carbon sinks, are threatened by the climate crisis. According to a report published in May by the International Union for Conservation of Nature (IUCN), More than 50 per cent of the world’s mangrove ecosystems are at risk of collapse by 2050. The main threats to these forests are human activities and the resulting climate change. These include deforestation, pollution, dam construction, rising sea levels and more frequent violent storms. According to IUCN estimates, climate change threatens a third of the mangrove ecosystems studied. Moreover, nearly 20 per cent of the mangroves assessed were considered high risk, classed as either “endangered” or “critically endangered,” indicating that these areas are at serious risk of collapse.
To protect these precious “blue carbon ecosystems,” several programmes are being deployed around the world. These include the Repic project, launched in 2019 by French marine biologists Andromède Océanologie, which aims to restore seagrass in the Mediterranean Sea. Or the “Blue Carbon Initiative,” a global programme to mitigate climate change through the restoration and sustainable use of coastal and marine ecosystems. — ETX Studio
