Herbland Alain auteur aut IRD Voituriez B. auteur aut IRD text bookSection fre text/pdf reformatted digital access A long duration station (60 hours) was covered where an active upwelling was expected to occur (Cap Timiris area, Mauritania). As soon as the wind enhanced (from 4-5 m/s to 11 m/s) the surface temperature decreased and nitrate concentration increased. A highly significant negative correlation was found between the temperature at 10 m and the time (r= -0.966, n=21). Surface heating due to solar irradiation occured each day. The mean decrease of surface temperature was one degre per day over 60 hours. The maximum upward velocity determined from the vertical displacement of the isotherms and nitrate isolines over 15 h intervals was about 4.5 x 10-2 cm/s. From that speed, the nitrate input in the euphotic layer is calculated and the potential production estimated at 21 g C/m2/d. From that value and in situ primary production measurements, the upwelling efficiency is evaluated at 30-40% for the first level of the food chain. (Résumé d'auteur) specialized UPWELLING FONCTIONNEMENT DE L'ECOSYSTEME VITESSE CONSEQUENCE ECOLOGIQUE TEMPERATURE DE SURFACE VARIABILITE PRODUCTIVITE BIOLOGIQUE MAURITANIE 032DYNEAU 180 5/6 131-134 Copenhague CIEM 1982 Symposium on The Canary Current : Studies of an Upwelling System, Las Palmas (ESP), 1978/04/11-14 5/6 https://www.documentation.ird.fr/hor/fdi:42795 [F B42795] https://www.documentation.ird.fr/hor/fdi:42795 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/pleins_textes_6/b_fdi_37-38/42795.pdf IRD - Base Horizon / Pleins textes 1995-11-13 2006-05-27 fdi:42795 fre