Dinoflagellate cysts production, excystment and transport in the upwelling off Cape Blanc (NW Africa)

To extend the understanding of dinoflagellate cysts production, excystment and vertical/lateral transport in water column, we compared upper cyst export production with associations concentrations subsurface nepheloid layer, bottom layer deeper column during active upwelling off Cape Blanc (NW Africa) August 2020. Export was collected by two drifting trap surveys; DTS1 an cell for 4 days DTS2 offshore filament 2 days. Subsurface, layers waters were sampled in-situ pumps along transects perpendicular to shelf break. During DTS1, light limitation hampered phytoplankton which might have influenced negatively due up- downward movement masses. Cyst increased at rim cell. For DTS2, up 3 times lower than that DTS1. Echinidinium delicatum had highest relative absolute abundances upwelling, zonneveldiae Bitectatodinium spongium filament, Impagidinium spp. Gymnodinium microreticulatum/nolleri most distal stations. Comparison without contents showed majority hatched before reaching displayed a dormancy period less 6 About 5% living reached and/or ocean floor. Living transported filament. In case ships exchange ballast studied region, they will take laterally cysts. Upon release port arrival, these potential become “invader species” can threaten economy health. Lateral observed (800 - 1200m depth) maximal extension about 130km Therefore, sediments region contain mixture regionally locally produced This insight contributes improvement environmental reconstructions blanc system based on downcore associations.