University of Cádiz study finds rising sea temperatures threaten blue carbon storage

Research conducted by the University of Cádiz indicates that rising sea temperatures may compromise the ability of seagrass meadows to function as natural carbon reservoirs. The study, published in ‘Communications Earth & Environment’, highlights a decline in the production of recalcitrant dissolved organic carbon—a type of organic matter resistant to degradation that remains in the water.

Traditionally, blue carbon studies have focused on organic matter buried in sediments. However, this research emphasizes that the compounds released by plants into the water represent a significant reserve that has been largely overlooked in traditional calculations. The findings suggest that both sedimentary and dissolved carbon reserves are of a similar magnitude.

The study was a collaborative effort involving the Institute of Marine Research in Vigo, the Institute of Marine Sciences in Barcelona, and the Leibniz Centre for Tropical Marine Research in Germany. Researchers noted that current estimates of the carbon sequestration capacity of seagrass meadows may be undervalued if only buried sediment is accounted for.