Study reveals the high carbon sequestration potential of kelp algae

A new study published in the scientific journal Scientific Reports highlights the fundamental role of kelp forests on the northern coast of Portugal in capturing and storing carbon—a significant contribution to climate change mitigation.​

The research, led by scientists from MARE – Center for Marine and Environmental Sciences and CIIMAR – Interdisciplinary Center for Marine and Environmental Research, focused on the kelp species Laminaria hyperborea and Saccorhiza polyschides, which are abundant in northern Portugal. Through detailed measurements of biomass and carbon composition at various points along the coast, the researchers estimated that these marine forests store approximately 16,500 tons of carbon in their biomass above the seabed.

In addition to storage capacity, the study also quantified annual carbon sequestration—that is, the amount of carbon permanently fixed by algae. The results indicate a rate of about 1,900 tons of carbon per year, which represents about 34% of the total estimated for Portuguese coastal ecosystems, such as salt marshes and seagrass beds.

Although the area covered by kelp (around 5,189 hectares) is smaller than that occupied by other marine habitats, the authors point out that its efficiency in fixing carbon per unit area is comparable or superior, underlining the ecological and climatic importance of these ecosystems.

The authors of the study argue that these kelp forests—often overlooked in climate mitigation strategies—should be recognized as important blue carbon reservoirs and therefore integrated into marine conservation and climate change policies.

The study recommends enhanced appreciation and protection of these areas through monitoring, conservation, and eventual restoration, highlighting their essential role in climate regulation, biodiversity protection, and marine ecosystem health.

To access the article, click HERE

Photograph by David Jacinto