Ecosystem Service Quantitative Assessment: Carbon Retained by Phytoplankton in a Eutrophic Gulf

The role of coastal marine ecosystems, especially saltmarshes, seagrass beds, and mangroves, has been substantial in mitigating climate change due to carbon sequestration. In particular, coastal eutrophic systems characterized by dense phytoplankton communities could be substantial contributors, as they retain significant amounts of carbon in organic form, representing, therefore, an important ecosystem service. However, the quantification of the contribution of phytoplankton in such a process is constrained by methodological gaps and uncertainties. In this paper, a stepwise procedure is presented to assess the carbon retained by phytoplankton in a coastal eutrophic system, and methodological limitations are discussed. The authors suggest that the contribution of phytoplankton in coastal eutrophic systems should be quantified and considered in the Blue Carbon balance within climate change mitigation frameworks.