Copepods distribution in relation to a Cape Ghir upwelling filament (Moroccan Atlantic coast)

The study of the Cape Ghir upwelling filament (31 degree N) focalizes to describe the dispersive mechanism, caused by the upwelling. The zooplankton was sampled during five oceanographic cruises conducted between 2008 and 2009. Surface temperature and chlorophyll "a" were also measured along with sampling. The distribution of environmental parameters accused extensions that show the path of the filament. Copepods constitute the largest fraction of zooplankton community and represented by 86 species, majorly dominated by Acartia clausi and Oncaea venusta. A number of species of deep or cold waters have been recorded in the area corresponding to a net resurgence of cold water. The analysis of the copepods distribution allowed to view the path of the filament at different times of the year. The distribution of the species A. clausi, neritic specie was observed in the open ocean, shows a result of this dynamic.Original Abstract: L'etude du filament d'upwelling de Cap Ghir (31 degree N) a ete entreprise afin d'enoncer le mecanisme de dispersion, engendre par la resurgence d'eau profonde. Cinq campagnes oceanographiques ont ete realisees entre 2008 et 2009. Au cours de ces campagnes, la collecte du zooplancton a ete realisee en meme temps que la mesure de la temperature de surface et la chlorophylle < a >. La repartition des parametres du milieu accuse des extensions qui mettent en evidence le trajet du filament. Les copepodes constituent l'essentiel du zooplancton et sont representes par 86 especes et domines par Acartia clausi et Oncaea venusta. Quelques especes profondes ou d'eaux froides rencontrees dans la zone temoignent d'une nette remontee d'eaux froides. L'analyse de la repartition des copepodes a permis de visualiser le trajet du filament a differentes periodes de l'annee. La distribution de l'espece A. clausi, espece neritique recensee au large, temoigne en consequence de cette dynamique.