The resistance of an east border upwelling system was investigated using relative index of marine pelagic biomass estimates under a changing environment spanning 20-years in the strongly exploited southern Canary Current Large marine Ecosystem (sCCLME). We divided the sCCLME in two parts (north and south of Cap Blanc), based on oceanographic regimes. We delineated two size-based groups (“plankton” and “pelagic fish”) corresponding to lower and higher trophic levels, respectively. Over the 20-year period, all spatial remote sensing environmental variables increased significantly, except in the area south of Cap Blanc where sea surface Chlorophyll-a concentrations declined and the upwelling favorable wind was stable. Relative index of marine pelagic abundance was higher in the south area compared to the north area of Cap Blanc. No significant latitudinal shift to the mass center was detected, regardless of trophic level. Relative pelagic abundance did not change, suggesting sCCLME pelagic organisms were able to adapt to changing environmental conditions. Despite strong annual variability and the presence of major stressors (overfishing, climate change), the marine pelagic ressources, mainly fish and plankton remained relatively stable over the two decades, advancing our understanding on the resistance of this east border upwelling system.

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The chemical composition of essential oils and floral waters obtained by steam distillation from both fresh and dried plants of Ocimum basilicum L. from Dakar and Kaolack regions, Senegal were studied by GC and GC/MS. The main constituents identified in the oils were estragole and linalool. Estragole represented 73.3 and 70.2% (Dakar); 79.0 and 75.2% (Kaolack) and linalool constituted 12.8 and 11.7% (Dakar); 11.5 and 12.9% (Kaolack) in the oils from fresh and dried plants of O. basilicum, respectively. The most representative compounds identified in the floral waters was linalool. It was 50.5 and 51.3% in Dakar and was followed by camphor (15.4 and 17.0%), estragole (14.9 and 12.1%) and 1,8-cineole (5.9 and 6.4%). In the floral waters from Kaolack, linalool constituted 57.9 and 56.6%. Other 2 representative components were estragole (10.0 and 9.1%), 1,8-cineole (5.9 and 6.4%), geraniol (5.2 and 5.1%) and camphor (4.1 and 4.1%) in the floral waters from fresh and dried plants from Kaolack, respectively. This study showed that both essential oils and floral waters of O. basilicum from Dakar and Kaolack are characterized by the same constituents. However, oils and floral waters differ by their contents in estragole and linalool.

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