2024/09/01 by María González-Martín, Andrés S. Rigual‐Hernández, Emı́lia Salgueiro +2 · 1 voice
Earth and Planetary Sciences · #Marine and coastal ecosystems #Oceanographic and Atmospheric Processes #Geology and Paleoclimatology Research
paper · doi:10.1016/j.marmicro.2024.102398
openalex publication_date 2024/09/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/23
This study investigates the abundance, composition, and biogeographical distribution of coccolithophores in the water column of the northwestern Iberian coastal upwelling system during late summer 2022. Coccolithophore data were compared with in situ measurements of physical, chemical, and biological parameters, as well as with satellite data and the upwelling index (UI) for the study area. Canonical Correspondence Analysis (CCA) was performed to determine the relationships between coccolithophore assemblages and environmental variables. The results reveal a latitudinal and longitudinal gradient in coccolithophore abundance, with higher concentrations towards the north and east, indicating a stronger influence of coastal upwelling near the coast (stations CA-7, CA-8, CA-4). Our data suggest that the source of upwelled water in the north (Eastern North Atlantic Central Waters of subpolar origin, ENACWsp) differs from that in the south (ENACWst, of subtropical origin). Significant correlations between UI and the total abundance of coccoliths and coccospheres underscore the role of upwelling in coccolithophore distribution. Additionally, correlations with fluorescence and turbidity indicate that coccolithophores contribute substantially to primary production in the region. Certain species are proposed as paleoenvironmental indicators due to their affinity for specific environmental conditions. The small Noëlaerhabdaceae group (small Gephyrocapsa group + Emiliania huxleyi ) serves as a proxy for primary productivity and intense upwelling, while Florisphaera profunda is associated with upwelling relaxation and low productivity. Discrepancies with satellite data are attributed to their limitations in detecting subsurface biological processes. This study also supports the use of the N-ratio in water column samples, not just in sediments, and improves the understanding of primary productivity at the Western Iberian Margin during the upwelling season. • Spatial distribution of coccolithophores in the Western Iberian Margin was studied. • Coccolithophore abundance is significantly correlated with upwelling intensity. • Latitudinal variability reflects differences in the upwelled water masses. • Coccolithophores significantly contribute to Chl- a levels during summer. • Florisphaera profunda serves as a proxy for low upwelling, except on the coast.