Written by: Mohammad Shawkat Hossain

There is currently a  paucity of information how much blue carbon is stored in and sequestered by Southeast Asian (SEA) seagrass meadows. The IOC Sub-Commission for the Western Pacific (WESTPAC) working group, with the key seagrass researchers from Malaysia, Philippines, Thailand, Viet Nam, India, Myanmar and Indonesia have reported how much carbon can be stored in seagrass meadows and their sequestration potential in the countries of Southeast Asia including the Andaman and Nicobar Islands of India.

Although the coastal and marine habitats along the SEA countries contain diverse seagrass species and can store huge amounts of organic carbon, the loss of seagrass meadows will trigger remineralization in the sediment, which will CO₂ emissions. We are currently losing 2.82% seagrass cover per year in SEA. If this rate of decline continues, researchers predicted, there will be no seagrass meadows by 2060 in this region.

Dr. Mohammad Shawkat Hossain, Lecturer, INOS, UMT shared location and carbon estimates information found along the coasts in Malaysia. This regional research is led by Excellence Center for Biodiversity of Peninsular Thailand (Prince of Songkla University).

This world-first study revealed total organic carbon stored in seagrass biomass and sediment of SEA is 5 times higher than previously recorded for the Indo-Pacific. Malaysia has higher in mixed than monospecific seagrass meadows, with profoundly large-sized Enhalus acoroides that enhanced ability to store more carbon than other species.

“Because of wide the range of variations in meadow size, coupled with disturbances, current carbon storage is 198 – 19 Mg ha^-1_,” Dr. Shawkat said. He continued, “since Malaysia is still in the list of least amounts of annual blue carbon loss among SEA countries, relevant stakeholders should take the necessary actions to address sustainable management and conservation of seagrass meadows, and include it in the national policies and agendas, realising their potential for climate mitigation”.

The study has been published in the Science of the Total Environment (https://www.sciencedirect.com/science/article/abs/pii/S0048969721019288).

“Regional networking and mapping blue economy sources will help researchers, managers and conservationists to identify threats and develop strategies as nature-based solution to protect coastal and marine habitats which is critical for mitigating climate change,” Dr. Shawkat said.