Marine plant life sucks 2 billion tonnes of carbon dioxide from the atmosphere every year, but most of the plankton responsible never reaches the seabed to become a permanent carbon store.
Mangrove forests, salt marshes and seagrass beds are a different matter. Although together they cover less than 1 per cent of the world’s seabed, they lock away well over half of all carbon to be buried in the ocean floor. They are estimated to store 1,650 million tonnes of carbon dioxide every year — nearly half of global transport emissions — making them one of the most intense carbon sinks on Earth.
Their capacity to absorb the emissions is under threat, however: the habitats are being lost at a rate of up to 7 per cent a year, up to 15 times faster than the tropical rainforests. A third have already been lost.
Halting their destruction could be one of the easiest ways of reducing future emissions, says report, Blue Carbon, a UN collaboration.
With 50 per cent of the world’s population living within 65 miles of the sea, human pressures on nearshore waters are powerful. Since the 1940s, parts of Asia have lost up to 90 per cent of their mangrove forests, robbing both spawning fish and local people of sanctuary from storms. (Read More)