Composition and Distribution of Plankton Communities in the Atlantic Sector of the Southern Ocean
Valentina V. Kasyan,
Dmitrii G. Bitiutskii,
Aleksej V. Mishin,
Oleg A. Zuev,
Svetlana A. Murzina,
Philipp V. Sapozhnikov,
Olga Yu. Kalinina,
Vitaly L. Syomin,
Glafira D. Kolbasova,
Viktor P. Voronin,
Elena S. Chudinovskikh,
Alexei M. Orlov
Affiliations
Valentina V. Kasyan
Laboratory of Systematics and Morphology, A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences (NSCMB FEB RAS), 690041 Vladivostok, Russia
Dmitrii G. Bitiutskii
Sector of the World Ocean, Azov-Black Sea Branch of the Russian Federal Research Institute of Fisheries and Oceanography (“AzNIIRKH”), 344002 Rostov-on-Don, Russia
Aleksej V. Mishin
Shirshov Institute of Oceanology, Russian Academy of Sciences (IO RAS), 117997 Moscow, Russia
Oleg A. Zuev
Shirshov Institute of Oceanology, Russian Academy of Sciences (IO RAS), 117997 Moscow, Russia
Svetlana A. Murzina
Environmental Biochemistry Laboratory, Institute of Biology of the Karelian Research Centre of the Russian Academy of Science (IB KarRC RAS), 185910 Petrozavodsk, Russia
Philipp V. Sapozhnikov
Shirshov Institute of Oceanology, Russian Academy of Sciences (IO RAS), 117997 Moscow, Russia
Olga Yu. Kalinina
Shirshov Institute of Oceanology, Russian Academy of Sciences (IO RAS), 117997 Moscow, Russia
Vitaly L. Syomin
Shirshov Institute of Oceanology, Russian Academy of Sciences (IO RAS), 117997 Moscow, Russia
Glafira D. Kolbasova
N.A. Pertsov White Sea Biological Station, Faculty of Biology, M.V. Lomonosov Moscow State University (WSBS MSU), 119234 Moscow, Russia
Viktor P. Voronin
Environmental Biochemistry Laboratory, Institute of Biology of the Karelian Research Centre of the Russian Academy of Science (IB KarRC RAS), 185910 Petrozavodsk, Russia
Elena S. Chudinovskikh
Sector of the World Ocean, Azov-Black Sea Branch of the Russian Federal Research Institute of Fisheries and Oceanography (“AzNIIRKH”), 344002 Rostov-on-Don, Russia
Alexei M. Orlov
Shirshov Institute of Oceanology, Russian Academy of Sciences (IO RAS), 117997 Moscow, Russia
In recent decades, the waters off the Antarctic Peninsula and surrounding region have undergone a significant transformation due to global climate change affecting the structure and distribution of pelagic fauna. Here, we present the results of our study on the taxonomic composition and quantitative distribution of plankton communities in Bransfield Strait, Antarctic Sound, the Powell Basin of the Weddell Sea, and the waters off the Antarctic Peninsula and South Orkney Islands during the austral summer of 2022. A slight warming of the Transitional Zonal Water with Weddell Sea influence (TWW) and an increase in its distribution area was detected. Among the pelagic communities, three groups were found to be the most abundant: copepods Calanoides acutus, Metridia gerlachei, and Oithona spp., salpa Salpa thompsoni, and Antarctic krill Euphausia superba. Euphausiids were found in cases of low abundance, species diversity, and biomass. In the studied region, an increase in the amount of the salpa S. thompsoni and the euphausiid Thysanoessa macrura and the expansion of their distribution area were observed. Significant structural shifts in phytoplankton communities manifested themselves in changes in the structure of the Antarctic krill forage base. The composition and distribution of pelagic fauna is affected by a combination of environmental abiotic factors, of which water temperature is the main one. The obtained results have allowed us to assume that a further increase in ocean temperature may lead to a reduction in the number and size of the Antarctic krill population and its successive replacement by salps and other euphausiids that are more resistant to temperature fluctuations and water desalination.