Polish Polar Research

In the years 1987-1989, within the frames of the international program "Greenland Sea Project", the Institute of Oceanology of Polish Academy of Sciences carried out the oceanographic investigations in the energoactive zones of the Northern Atlantic. The paper presents some results of these investigations, characterizing interannual variability of aero- and hydrophysical fields and the causal connections between hydrological and hydrobiological anomalies. Main results of these investigations indicate that the summer season of 1988 was an anomaly in the region of confluence of Barents and Norwegian Seas. This result is irrefutably confirmed by biological data concerning species, and hydrophysical data, such as light attenuation coefficient, fluorescence, spatial distributions of water temperature, salinity, density and current velocity, as well as mass and heat fluxes. It arises from these information that the southern border of the confluence zone was normally the heat „source", while in 1988 it was the heat „sink". The results obtained indicate two reasons responsible for such a situation. The first is the anticyclonic eddy structure of cold Barents Sea waters, penetrating the confluence zone. The second reason seems to be a mechanism blocking the transport of Atlantic water masses through the transect between Faeroe and Shetland Islands.

Changes taking place in weathered bedrock and vegetation of the ground moraine of Werenskiold glacier during about 50 years are presented. These results are based on phytosociological survey and analysis of the population structure of Saxifraga oppositifolia in 20 experimental fields and the analysis of physical and chemical features of the soils. In the process of succession, with chemical features not much changed and spongy structure just beginning, the number of vascular plants did not increase. In the process of succession the gradual increase in the density of S. oppositifolia population was observed. The size of its individuals and the share of flowering individuals also increased.

Quantitative data on meiobenthos distribution in four biotopes of the intertidal zone are presented. Differences in taxonomic composition and meiofauna abundance are influenced by the morphology of beaches and their sediment structure.

The list of 29 gastropod species and 33 species of bivalves occurring in Hornsund Fiord as well as their zoogeographic status are presented. The occurrence and role of Mollusca in particular parts of the fiord are discussed.

Parasitic isopods (Aega antarclica and Gnathia calva) were discovered on fishes collected during Polish expeditions to the Atlantic sector of the Southern Ocean. Pranizae of G.calva infected 14.5% of Nololhenia corriceps neglecta and 16% of Notothenia rossi marmorata. The infestation rates are probably underestimated.

In material collected from birds (Aves, Procellariiformes) in the South Georgia region by Polish Antarctic Marine Research Expedition in 1976 the following mallophagan species were found: Docophoroides brevis (Duf.), Naubates fuliginosus (Tasch.), Pseudonirmus gurlti (Tasch.) and Trabeculus hexacon (Wat.). These are the first records from this region.