Significant Role In Circulation Research Articles

Cross-shelf structure and distribution of mesozooplankton communities in the East-Siberian Sea and the adjacent Arctic Ocean

The East-Siberian Sea (ESS) plays a significant role in circulation of surface water and biological production in the Arctic, yet due to its remote location and historically difficult sampling conditions remains the most understudied of all Arctic shelf seas, with even baseline information on biological communities absent in literature. We aim to fill this gap by describing the distribution and community structure of mesozooplankton in the ESS and the adjacent Arctic Ocean based on recent (September 2009, 2015) as well as historical (August–September 1946, 1948) observations. We found that the overall biomass and abundance during our studies were significantly lower than in the adjacent Chukchi Sea, but higher than historical estimates from the ESS, around 25–35 mg DW m−3. The diversity was low and characteristic for other Arctic shelf seas, with increasing number of species in deeper waters. Biomass was highest at the shelf break, where it approached 70 mg DW m−3, and was mainly composed of the large copepod Calanus glacialis. On the shelf, abundance and biomass were low (10–20 mg DW m−3) and was dominated by small copepods and chaetognaths. Several distinct assemblages of zooplankton were identified and related to the physical properties of the water masses present. A striking result was the presence of both Atlantic and Pacific expatriates in offshore waters close to the shelf break, but generally not on the shelf itself. Tracking these advected organisms could be a useful tool in determining the pathways, extent, and transit time of Atlantic and Pacific water entering the Arctic.

The role of wild boars (Sus scrofa) in circulation of trichinellosis, toxocarosis and ascariosis in the Slovak Republic

Abstract Wild boars (Sus scrofa) can play a significant role in circulation and maintenance of certain parasites in the environment. The aim of this study was to determine the seroprevalence of trichinellosis, toxocarosis and ascariosis in wild boars hunted in the Slovak Republic in 2003 and 2004. Anti-Trichinella antibodies were detected in 1.3 % out of 1035 wild boars investigated. No significant differences were observed regarding the positivity of wild boars according to age and sex in both years. The examination of 1173 wild boars for anti-Toxocara antibodies revealed 7.2 % seropositive individuals. Anti-Ascaris antibodies were detected in 6.1 % out of 411 animals examined. Both, anti-Trichinella and anti-Toxocara antibodies were determined in 0.6 % cases. Presence of anti-Trichinella and anti-Ascaris antibodies was recorded in 0.8 % animals. Concurrent infection caused with Toxocara and Ascaris was observed in 1.5 % individuals. This study concentrates on the role of wild boars in circulation and on the maintenance of trichinellosis, toxocarosis and ascariosis in the Slovak Republic.

Satellite SAR observations of atmospheric and oceanic vortex structures in the Black Sea coastal zone

ERS-2 SAR and Envisat ASAR images of the north-eastern coastal zone of the Black Sea have revealed frequent manifestation of dynamic upper ocean and atmospheric boundary layer structures. In 1999–2004, IKI RAS carried out a series of experiments in the region of Novorossiisk–Gelendzhik to investigate the dominant processes associated with such dynamic features. Special focus was on oceanic vortices of small and medium scales at 2–20 km which are difficult to register by ship measurements or satellite optical instruments. Meanwhile, they play a significant role in circulation and mixing processes in the coastal zone. Atmospheric synoptic vortices and local mushroom flows are also discussed.