Carbon dioxide captured and stored in the ocean is called blue carbon. Seagrass meadows, in particular, are important blue carbon sinks, storing massive amounts of carbon in mud and sand for hundreds to thousands of years. Seagrass meadows are large shallow-water areas where the seafloor is covered with seagrass growing in mud or sand. By keeping the carbon out of the atmosphere, they help regulate our climate system. However, a recent study of an Australian estuary found that seagrass meadows are not all equally good at storing carbon.
When the researchers of this study analyzed mud and sand samples from in the seagrass meadow, they found huge variation in its ability to store carbon. Their analysis revealed that carbon storage increases with a higher proportion of mud and carbon inputs from local, non-seagrass sources such as runoff from nearby land. The lead author of this study and a postdoctoral scientist in the research group I work in, Aurora Ricart, said, "this and similar studies will improve quantification of seagrass carbon stocks and tell us more about their capabilities as global carbon sinks."
With better characterization of high carbon storage seagrass meadows, governments can determine which meadows need protection. This will secure their ability to store carbon long into the future, helping mitigate climate change.