Pound for pound, mangroves can sequester four times more carbon than rainforests can
Researchers estimate the monetary value of the benefits, or “ecosystem services,” provided by mangroves at $194,000 per hectare annually. Multiplied by their global extent, that means the world’s remaining mangroves provide around $2.7 trillion in services every year.
But a new study suggests the real value of mangroves may be higher still. It finds much more carbon may be locked up in mangrove soil than previously believed..
The study, published recently in Environmental Research Letters, finds mangrove soil held around 6.4 billion metric tons of carbon in 2000. This is dramatically higher than previous estimates that pegged the carbon content of mangroves (both soil and biomass) at around 4.19 billion metric tons.
They act as storm barriers, protecting inland areas from flooding and erosion by dissipating the energy of big waves.
The coastal forests serve as nurseries for a variety of marine fish, underpinning global fisheries and providing additional food for coastal communities.
Straddling the interface of land and sea, mangrove forests are of two worlds. Their branches provide homes for lizards, snakes and nesting birds, while their roots, when submerged, become protective nurseries for baby fish and sanctuaries for marine mammals.