A total of sixty five taxa of marine phytoplankton (diatoms, dinoflagellates, silicoflagellates and cyanoprokaryotes) were recorded in the transect from the cold region of the Antarctic (Weddell Sea) up to La Plata Bay, Argentine in the late austral summer (March 1989). Diatoms were the dominant group in a south-north transect from the Seal-Bay (Princess Martha Land, the Antarctic). Most of the phytoplankton species of the cold Antarctic region disappeared around 50°S where there is a steep water temperature gradient. The diatom flora declined in the regions of increasing temperature, i.e. between 60° and 50° S and was replaced by dinoflagellates of the genus Ceratium. Large centric diatom genera Corethron, Rhizosolenia, Chaetoceros and Dactyliosolen represented the most apparent phytoplankton part. The most common of the small centric diatom genera were Thalassiosira, Asteromphalus, Actinocyclus and Coscinodiscus, while several species of Navicula and Nitzschia were the most abundant pennate forms. The presence of a considerable number of freshwater pennate diatoms, characterized as indifferent in the halobion spectrum and mostly periphytic, might be attributed to survival strategies during their development on the floating coastal ice.
Phytoplankton samples were collected at 141 stations in the Norwegian, Greenland, Barents and Baltic seas, in July-August 1992 and July-August 1993. In fifteen of these stations 22 unarmoured dinoflagellate species from the order Gymnodiniales belonging to the genera Amphidinium, Cochlodinium, Gymnodinium, Gyrodinium, Torodinium and Polykrikos have been found. Data on 16 species are given here, including synonyms, size or size variation, localities and environmental factors (temperature and salinity at the surface). 14 species are illustrated.
Suspended matter, phytoplankton and light attenuation were investigated in various North East Greenland, Svalbard and Siberian river mouths in 1992-1994. The amount of mineral suspensions well correlated with freshwater discharge in the case of tidal glacier bays, while such correlation in Siberian rivers and pack ice meltwater was not found. Freshwater phytoplankton species were found in Siberian estuaries only and in two other ecosystems marine and ice phytoplankton species prevailed. The light attenuation connected with freshwater discharge seems to be a key factor limiting primary production in coastal Actic waters in the summer. The amount of glacial suspensions well correlated with the salinity drop in the case of Svalbard, while Siberian river estuaries produced very turbid waters with the suspension loads not correlated to freshwater or depth.
This paper reports the preliminary results from the studies on the scanning electron microscopical studies on chrysophycean cysts collected in ponds and streams of King George Island (South Shetlands). The cysts play an important role as the survival developmental stages. Fifteen morphotypes are described, six of which are new for science. Particular attention has been paid to the anatomy of the pore, collar structure and to the ornamentation of the cyst surface.
The paper presents the results of seven-year survey of Antarctic seals along the western shore of Admiralty Bay, King George Island, South Shetland Islands. Five species were monitored during seven of the eight years, between 1988-95, excluding 1993. Numbers of elephant seals and Antarctic fur seals showed strong annual cycles, fur seals with two seasonal peaks. These of the other three species were more irregular. Fewer Weddell seals were seen in 1994 and 1995 then during the period 1988-92; with this exception, no overall trend in numbers was apparent during the period 1988-95.
Starostinella nordica gen. et sp. n. is described from the uppermost Permian (Kapp Starostin Formation) of the Kapp Starostin (Isfjorden) in West Spitsbergen. The new genus is attributed to Trachypsammiidae Gerth - a family incertae sedis among Cnidaria. Members of the Trachypsammiidae have been previously associated with different higher rank taxa within the Cnidaria, or their skeletons were interpreted as a result of symbiosis of a cladochonoidal organism (Tabulata) with an indeterminate hydroid or stromatoporoid. S. nordica gen. et sp. n. seems to support the latter assumption. Hydrocoralla of S. nordica have a simpler structure than those of other Trachypsammiidae and are branching like those of Cladochonus. Their thick-walled, horn-shaped hydrocorallites are surrounded with a very thick cortical zone of sclerenchyme organized into trabecular microstructure. The proper corallite wall is fibro-radial in structure, sharply distinct from the outer cortical zone.
Henryk Arctowski Station, the research station of the Polish Academy of Science in Admiralty Bay, King George Island, West Antarctica, is one of the most heavily visited bases in Antarctica. Between the seasons 1991/92 and 1996/97, 12884 tourists were recorded. A specially designed tourist trail was marked to divert visitors toward alternative attractions, not only the station buildings. Tourist management goals include: environmental protection, minimising waste and pollution, respecting the rules relating to protected areas, and prohibition of collections and souveniring.
Four Geodynamical Expeditions of the Polish Academy of Sciences carried through wide research seismic program in West Antarctica in 1979-1991. Three of these expeditions operated in the Bransfield Strait. The experiment of deep refraction and wide-angle reflection in West Antarctica focused on deep structure of the lithosphere, mainly of the Earth's crust. The network of deep seismic soundings (DSS) profiles covered all the Bransfield Strait. Five land stations on the South Shetland Islands, three stations on the Antarctic Peninsula and nine ocean bottom seismographs (OBS) recorded seismic waves, generated by explosions in a sea. The Bransfield Rift and the Bransfield Platform form a marginal basin against a volcanic arc of the South Shetland Islands. The paper presents new results of 2-D seismic modeling for network of five selected profiles. Four of them, ranging in lenght from 150 to 190 km, crossed main structures of the Bransfield Strait and the fifth, which connected the other ones and was 310 km long, ran along the Bransfield Rift. Two or three seismic models were presented for each profile. Finally, mutually corrected and controlled 2-D models of described profiles were constructed. They all presented spatial complex structure of the Earth's crust in a young rift of the Bransfield Strait, including extent of its main element i.e. anomalous high velocity body (HVB) (Vp > 7.4 km/s), detected in 10-30 km depth range except profile DSS-4 (southwest part of the Bransfield Strait). This inhomogeneity is interpreted as intrusion of the upper mantle (?asthenosphere) during stretching of the continental crust. The Moho discontinuity was found at depth 30-35 km, with velocities equal to about 8.1 km/s.