Blue Carbon

The growing emission of carbon dioxide from a wide range of human activities is causing unprecedented changes to the land and sea. Identifying effective, efficient and politically acceptable approaches to reduce the atmospheric concentration of CO2 is one of society’s most pressing goals.

One of the most promising new ideas to reduce atmospheric CO2 and limit global climate change is to do so by conserving our coastal vegetations such as mangroves, sea grasses and salt marsh grasses. Such coastal vegetation, dubbed “blue carbon”, absorbs carbon far more effectively (up to 100 times faster) and more permanently than terrestrial forests. Carbon is stored in peat below coastal vegetation habitats as they grow vertically. 

Because the sediment beneath these habitats is typically anoxic, organic carbon is not broken down and released by microbes. Coastal vegetation also continues to sequester carbon for thousands of years in contrast to forest, where soils can become carbon-saturated relatively quickly. Therefore, carbon offsets based on the protection and restoration of coastal vegetation could be far more cost effective than current approaches focused on trees. Furthermore, there would be enormous ad-on benefits to fisheries, tourism and in limiting coastal erosion from the conservation of blue carbon.

Furthermore, these coastal vegetation environments are big nurseries for juvenile fish and numerous other marine life, they protect against erosion and offer protection during storms and rising sea levels due to climate change so it’s really a win-win situation to protect these precious habitats.

At the moment we are losing this habitat at a rate of about 1-5% a year, mainly due to mangrove areas being cleared for shrimp farming and coastal development, sea grasses are lost because of bad water quality and pollution and sea marshes are also being cleared for development projects.

Although there is far more area covert in rainforest, these coastal vegetation are just as vital to offset carbon as they can absorb at a much faster rate and more permanently. 

For more information about ‘Blue Carbon’, click here.