Following the successful May 2025 expedition in Portlligat, Spain, the GAME-CSIC team began detailed laboratory processing of the 8 newly collected sediment cores—adding to the 32-core dataset central to the EFFECTIVE Project’s blue carbon analysis.

Each core has been carefully opened, dried, and subdivided into centimetric sections. These sub-samples are undergoing loss on ignition testing to determine organic carbon and inorganic carbonate content in the sediment—critical indicators for evaluating blue carbon storage potential in Posidonia oceanica habitats.

In addition to chemical analysis, one core of each replicate will have all samples sent for carbon dating, producing a multi-millennia history of Portlligat. This temporal dimension provides vital context for interpreting carbon sequestration rates and long-term ecosystem resilience.

Early data analysis has already begun to reveal distinct trends, with strong groupings emerging based on sediment origin and composition. The latest cores are expected to reinforce these patterns and add granularity to habitat-specific carbon stock estimates. These findings are not only pivotal for Portlligat’s ecological mapping but will also feed directly into the EFFECTIVE Project’s broader goals of quantifying and protecting marine carbon sinks.