Current status of seagrass beds and blue carbon sink capacity in marine protected areas along the coast of Korea
Seagrass meadows provide a wide range of ecosystem services, including maintaining marine biodiversity, protecting coasts, and stabilizing sediment. They are also recognized as important blue carbon ecosystems due to their high productivity and capacity for long-term organic carbon (Corg) sequestration in sediments. This study assessed the distribution of seagrass meadows and blue carbon storage within Korea’s marine protected areas (MPAs) using monitoring data, research reports, and published scientific literature. Seagrasses were identified in 14 of the 39 designated MPAs, with seven of the nine seagrass species reported along the Korean coast recorded within these MPAs. The total seagrass area within MPAs was estimated at 1.33 km2, accounting for less than 2.5% of the total seagrass extent in Korea. Zostera marina occupied the largest proportion of this area (71.2%), whereas Phyllospadix japonicus and P. iwatensis together accounted for only 8.6% of the total area. However, these two species contributed approximately 55% of the total biomass, indicating substantial interspecific differences in area and biomass contributions. The estimated sediment Corg stock to a depth of 1 m was 9,950 Mg C, while the total organic carbon stock, including seagrass biomass carbon, was estimated at 10,108.8 Mg C. However, research on seagrass within Korean MPAs, as well as evaluations of the ecological effectiveness of MPA designation, remains very limited. This study provides a comprehensive assessment of seagrass conservation status and blue carbon storage within Korean MPAs, offering baseline information for future conservation and management strategies.