at the Northern Margin
of the North Atlantic Gyre (June
August 2001)
G. M. Vinogradov1, M. E. Vinogradov2, and E. I. Musaeva2
1 Severtsov Institute of Problems of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia
2 Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russia
Received March 25, 2002
Abstract—The vertical distribution of mesoplankton was studied over a single season in 2001 at two sites in
the western and eastern parts of the northern margin of the North Atlantic gyre. Plankton was both sampled with
the use of a BR 113/140 net and observed from a deep-water manned submersible. In the near-slope waters
southeast of Newfoundland (site Titanic), an intensive interaction between the subtropical and subpolar waters
and plankton communities occurs. The subtropical gyre community, which is more mature from the succession
viewpoint, creates a “network” of carnivores and scavengers (shrimp and smaller animals) feeding upon the
plankton supplied from the north and thus increasing their own biomass. Due to the features of the hydrological
conditions, in 2001, in contrast to other years, the plankton supplied from the north was dominated by small
copepods, while the number of the larger Calanus hyperboreus was small. Perhaps due to this fact, the abun-
dance of macroplanktonic shrimp decreased, while the abundance of mesoplanktonic carnivores (Themisto,
Sagitta, and Pareuchaeta) increased. In the eastern part of the ocean, in the Porcupine abyssal plain (site Bis-
mark), the contrasts in the frontal interfaces decrease and the pattern of the community interaction becomes less
expressed. While the vertical distribution of plankton at site Titanic is characterized by a series of extraordinary
features, the distribution at site Bismark is much more ordinary.
Pleiades Publishing home page | journal home page | top
If you have any problems with this server, contact webmaster.