Seagrass meadows is one of the major blue carbon ecosystems, assume a pivotal role in the carbon cycle and climate regulation. Seagrass adeptly absorb a substantial amount of CO₂ through photosynthesis, converting it into organic matter and storing carbon within their tissues and sediments. By means of comparing diverse monitoring techniques and extensive datasets, we delivered an exhaustive analysis of the carbon sequestration and storage capacity exhibited by seagrass vegetation.
In this study, biomass, net primary productivity (NPP), and community structure of typical seagrass communities with 6 species were measured using harvest and rhizome & leaf marking  methods, the most direct and classical approaches for seagrass biomass and total net primary productivity (NPP), in three typical seagrass meadows from northern and southern China. By collecting data from 53 papers, we have uncovered variations of vegetative carbon sequestration abilities in totally 12 seagrass genera under different geographical locations and environmental conditions. We have combined the data from our field observation and data collection, and found that seagrass biomass in China (0.79~564.2 gC m^-2) exhibited high interspecific variation (p=0.0002), and which were predominantly concentrated in roots (41%~87% of total biomass). At the same time, seagrass in China demonstrated lower NPP (0.40 ± 0.13 gC m^-2 d^-1) than global (0.85 gC m^-2 d^-1) due to their sparse density (4~823 shoots m⁻²) caused by the anthropogenic disturbance and species composition. These findings provide invaluable references for managers and policymakers in safeguarding and rehabilitating the well-being of seagrass meadows, while also capitalizing on their potential as carbon sinks to address the challenges presented by climate change.
 

Blue carbon,Net primary productivity,Biomass,seagrass meadows