|
|
|
|
|
Paterne, Martine; Kallel, Nejib; Labeyrie, Laurent; Vautravers, Maryline J.; Duplessy, Jean-claude; Rossignol-strick, Martine; Cortijo, Elsa; Arnold, Maurice; Fontugne, Michel. |
The Mediterranean Sea hydrology at the time of the Heinrich formation in the North Atlantic Ocean was analyzed by comparing sea surface temperatures (SSTs) and oxygen isotope composition of seawater (delta w) changes during the past 75 kyr in two marine cores. These were compared to the palynological variations derived in the Mediterranean Sea core. During the last glacial the two oceanic SST records show similar and synchronous patterns, with several long-term cooling periods, ending by abrupt SST increases. At the time of the Heinrich events, cold SSTs and low salinity prevailed in the Mediterranean Sea. The freshwater budget was similar to the modern one, permitting the presence of a mixed forest on the Mediterranean borderlands. The post-Heinrich... |
Tipo: Text |
|
Ano: 1999 |
URL: https://archimer.ifremer.fr/doc/00239/35050/36799.pdf |
| |
|
|
Collos, Yves; Descolas Gros, Chantal; Fontugne, Michel; Mortain-bertrand, A; Chretiennot-dinet, Marie-josèphe; Frikha, Mg. |
Enclosing seawater samples in incubation bottles had 3 main effects on the phytoplankton: first, a large (5-fold in 12 h) increase of phytoplankton biomass, due to the release of grazing pressure by herbivores, Second, an increase (2-fold in 6 h) in ribulose biphosphate carboxylase specific activity (per unit chlorophyll a), which could be due to a smaller dependence on regenerated production (less heterotrophy on excreted compounds). This was also supported by a tight relationship between phosphoenol pyruvate carboxykinase activity and dissolved ammonium. Finally, the large changes in the carbon isotopic composition of the incubated particulate matter, which were highly dependent on the dissolved inorganic nitrogen concentration, were due mainly to... |
Tipo: Text |
|
Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00193/30413/28965.pdf |
| |
|
|
|