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| Minas, Hj; Coste, B. |
| Two types of stations were occupied: CTD hydrocast stations for water chemistry and continuous vertical profiles of chemical parameters in the upper 200 meter layer (SHET profiles). Selected biological stations were carried out mainly for primary productivity (in situ super(14)C method), phytoplankton biomass and photometric measurements (quantum- and spectroirradiance-meters) in the photic zone. Zooplankton was collected at nearly all the stations of the cruise in order to determine biomass and species composition. A long Peru-Galapagos connecting section with 19 stations was carried out for water chemistry down to 2000 meters. |
| Tipo: Text |
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| Ano: 1990 |
URL: http://archimer.ifremer.fr/doc/00268/37935/36016.pdf |
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| Minas, Hj; Minas, M. |
| An analysis of tropical upwelling systems shows a great range in the rate of increase of the standing stock expressed in terms of the water column chlorophyll content. Grazing appears to be the main factor responsible for lowering the rate of increase, especially in moderate and strong High Nutrient-Low Chlorophyll (HNLC) waters. A simple model comparing Net Community Production (NCP) rates with observed chlorophyll increase rates, leads us to conclude that phytoplankton population must present high specific growth rates on a daily rhythm in order to overcome grazing. Maximum specific growth rates (V(max)) calculated for daily total production (TP) are, in the two main upwelling areas, 137 d-1 off NW Africa and 1.04 d-1 off Peru. For extreme HNLC... |
| Tipo: Text |
Palavras-chave: NUTRIENTS; NEW PRODUCTION; GRAZING; TROPICAL OCEAN; ANTARCTIC. |
| Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/00100/21149/18768.pdf |
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| Coste, B; Le Corre, P; Minas, Hj; Morin, P. |
| Nutrient measurements were performed during the Mediprod IV cruise of the R.V. Jean Charcot in the whole western basin of the Mediterranean Sea, special attention being paid to the Alboran Sea and to the Strait of Gibraltar. From these data, new values for the nutrient budget of the Mediterranean Sea are obtained. It appears that dissolved organic nitrogen (DON) contributes to the total nitrogen input in an amount of more than 50%, and that the river runoff contribution accounts for less than 10% of the total nutrient input. High values of the N : P ratio in the Mediterranean Sea (> 20) are explained by the nitrogen and phosphorus content of the superficial layers of the water inflow into the Mediterranean Sea, together with mineralization processes... |
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| Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00267/37832/35913.pdf |
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| Minas, Hj; Bonin, M C. |
| Strong vertical mixing during winter in the northwestern Mediterranean Sea occurs with simultaneous ventilation of water masses. In the high turbulent deep water formation chimneys, with homogenous density from the sea surface to the bottom, the oxygen input, limited to the most intense winter period, reaches almost 10 super(3) l O sub(2) m super(-2). From Redfield's exchange coefficient, an oxygen flux of about 12 l m super(-2) d super(-1) can be calculated. Nearly the same flux can be derived from Broecker and Peng's piston velocity data, but in order to reach this value one has to assume that the sea surface film thickness averages 10 mu m. Biological oxygen fluxes produced by photosynthesis or respiration are almost negligible in comparison with the... |
| Tipo: Text |
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| Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00267/37807/35888.pdf |
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| Minas, Hj; Minas, M; Coste, B; Gostan, J; Nival, P; Bonin, M P. |
| Apparent nutrient consumption and oxygen production, representing net community production, appear among other methods to offer a valuable approach to new production. Net community production determinations were carried out a long time ago in the Mediterranean Sea, with the idea of comparing them with super(14)C-productivity measurements. Our main objective here is to summarize the results of these studies and to review them in relation to the latest discussions concerning productivity of the Sargasso Sea. In the main oligotrophic coastal waters of the Ligurian Sea, there is no evidence for positive net production in the subsurface oxygen maximum associated with the summer thermocline (Minas, Coste, 1964), and Reid's (1962) physical explanation of the... |
| Tipo: Text |
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| Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00267/37833/35914.pdf |
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