|
|
|
|
|
| Merceron, Michel; Gaffet, Jean-dominique. |
| Current recordings were performed near the middle of the great breakwater of Cherbourg ("Grande Digue", inner side) during two months of the 1993 summer. The data show that, in this site, the currents drive mostly westwards. They are driving eastwards only during the first half of flood. In the tidal cycle, there is only one current slack, at law tide. The most important velocities are observed during the high tides : 0.5 to 0.6 m.s-1• The fish net pens, which are located there, tend to speed up the undemeath currents and, thus, contribute to scatter the farm effluents. The temperature and salinity records are also displayed. _ |
| Tipo: Text |
Palavras-chave: Courant; Cage; Élevage; Poisson; Cherbourg; Current; Net pen; Farm; Fish; Cherbourg. |
| Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00082/19330/16924.pdf |
| |
|
|
| Lund-hansen, Lc; Vang, T. |
| Upwelling of cold. saline, and nutrient rich water was observed in late September 1999 along an east-west transect in the SW Kattegat. The Kattegat forms part of the transitional zone between the high saline North Sea and the low saline Baltic Sea. The upwelling occurred after an extended period of northward flow and eastern winds in the Kattegat, that changed into a southward flow as wind ceased. The upwelling was the result of a combination of high current speeds and bottom topography whereby the high-speed inflow water was forced towards the surface at the slope. Nutrient data show that the upwelling brought nutrient rich bottom water to the light exposed surface and a related strong (1943.5 ml(-1)) bloom of Pseudo-nitzschia pseudodelicatissima was... |
| Tipo: Text |
Palavras-chave: Courant; Upwelling; Front; Fluorescence; Chlorophylle-a; Inflow; Upwelling; Frontal structure; Fluorescence; Chlorophyll-a. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00321/43249/42980.pdf |
| |
|
|
| Merceron, Michel; Bentley, Daniel; Le Grand, Jacqueline; Lamort-datin, Laure; Kempf, Marc. |
| The environmental impact of a brown trout farm located in the Grande Rade de Cherbourg (Normandy) is reported. During observations the fish stock evolved within the range of 140 to 350 metric tons. Farm influence was researched on water column through hydrochemistry, phytoplankton, faecal bacteria and, on bottom, through grain size, organic matter, metals, macrobenthos. This report only deals with water column. Except ammonia, no hydrological parameter seems to be affected, even near to the net pens. Phytoplankton and coliform bacteria were not altered. An extra concentration of ammonia was detected at some tens meters from the raft, with favourable conditions. But generally it was impossible to observe it unless close to the farming structure, downward... |
| Tipo: Text |
Palavras-chave: Channel; Current; Faecal bacteria; Phytoplankton; Hydrology; Impact; Salmonid; Fish farm; Manche; Courant; Bactéries fécales; Phytoplancton; Hydrologie; Impact; Salmonidé; Aquaculture. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/1997/rapport-3342.pdf |
| |
|
|
| Thouvenin, Benedicte; Salomon, Jean-claude. |
| In order to reproduce and investigate the marine circulation in the coastal tidal zone, and especially its three dimensional nature, it appeared interesting to develop a numerical mode! which could take account of the real bottom topography and the variations of the free surface. Navier-Stokes equations are solved in a straight forward manner, generalizing a finite difference technique already used in two-dimensional vertical models. To test the computational program, the mode! was applied to a number of flat bottom schematic basins, where we reproduced wind driven currents and tide propagation. Then we considered the particular case of a real channel and, finally, density currents associated with a salty wall. Mode) results are compared to theoretical... |
| Tipo: Text |
Palavras-chave: Modèle; Courant; Tridimensionnel; Seine; Côtier; Model; Current; Three-dimensional; Seine; Coastal. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/00113/22440/20127.pdf |
| |
|
| |
|
|
|
