VARIABILITY OF HYDROLOGICAL AND HYDROCHEMICAL CONDITIONS OF GOTLAND AND GDANSK BASINS' BOTTOM WATERS BALTIC SEA IN 2015--2016
Abstract and keywords
Abstract (English):
The field data set obtained in 2015--2016 in the south-eastern part of the Baltic Sea within the exclusive economic zone EEZ of the Russian Federation revealed a rise in the values of the hydrological characteristics of the Gdansk and Gotland southern slope Basins bottom layer. It was caused by the increased frequency of the North Sea water intrusions and their advection into the bottom layer of basins. As a result of these intrusions the hydrochemical conditions of the near-bottom waters has changed. The highest values of the dissolved oxygen content coincided with the extremes of salinity and temperature. The content of phosphates and silica increased simultaneously with the decrease of concentration of dissolved oxygen. The variability of the parameters for two basins was different. An increase in the temperature and salinity values on the southern slope of the Gotland Basin was less obvious than that in the Gdansk Basin. The concentrations of dissolved oxygen within the Gotland Basin in the most cases besides the spring 2016 exceeded the values in the Gdansk Basin by 0.3--1.0~ml/l. The oxidation of the bottom sediment upper layer was observed in the Gotland Basin's southern slope, while the Gdansk Deep sediments had distinct hydrogen sulfide smell. The benthic communities of the Gotland were represented not only by the species which are tolerant to low dissolved oxygen content, but also by the young Macoma balthica. Anaerobic periods led to the absence of benthic macro- and meiofauna in the deep areas of the Gdansk Basin.

Keywords:
Baltic Sea, marine biology, oxidation/reduction reactions, Major Baltic Inflow, anoxic environments, benthic processes, benthos
Text
Publication text (PDF): Read Download
References

1. Cyberski, J. Climate, Hydrology and Hydrodynamics of the Baltic Sea // Geochemistry of Baltic Sea surface sediments - Warsaw: Polish Geological Institute#x2013;National Research Institute., 2011. - p. 55.

2. Drozdov, V. V., Smirnov, N. P. The climatic changes and bottom fishes of the Baltic Sea - St. Petersburg: RSHU Publishers., 2008. - 249 pp.

3. Emelyanov, E. M. Geochemistry of Suspended Matter and Sediments of Gdansk Basin and Sedimentation Processes // Geochemistry of the Sedimentary Process in the Baltic - Moscow: Nauka., 1986. - p. 57.

4. Emelyanov, E. M. Ferromanganese ore process in the Baltic Sea, // Litologiya i Poleznye Iskopaemye, 2011. - no. 3 - p. 227.

5. Emelyanov, E. M. Bottom sediments: distribution, grain size, mineralogy, geochemistry // The Baltic Sea System - Moscow: Nauchnyi mir., 2017. - p. 380.

6. Feistel, R., Nausch, G., Wasmund. N. eds. State and Evolution of the Baltic Sea, 1952#x2013;2005 // A Detailed 50-Year Survey of Meteorology and Climate, Physics, Chemistry, Biology, and Marine Environment - Hoboken: John Wiley ampersand Sons., 2008. - p. 380.

7. Fonselius, S. H. Hydrography of the Baltic deep basins, // Fish Board Sweden. Ser. Hydrogr., 1969. - no. 23 - p. 1.

8. Koroleff, F. Determination of nutrients: 6. Silicon // Methods of Seawater Analysis, edited by Grasshoff, K. - Weinheim: VCH., 1976. - p. 149.

9. Krechik, V. A., Kapustina, M. V., Bubnova, E. S., Gritsenko, V. A. Abiotic Conditions of Bottom Waters in the Gdansk Deep of the Baltic Sea in 2016, // Uchenye zapiski Rossiyskogo gosudarstvennogo gidrometeorologicheskogo universiteta, 2017. - no. 48 - p. 186.

10. Laine, A. O. Distribution of soft-bottom macrofauna in the deep open Baltic Sea in relation to environmental variability, // Estuarine, Coastal and Shelf Science, 2003. - no. 57 - p. 87.

11. Mohrholz, V., Naumann, M., Nausch, G., Kr#xFC;ger, S., Gr#xE4;we, U. Fresh oxygen for the Baltic Sea. An exceptional saline inflow after a decade of stagnation, // J. Mar. Syst., 2015. - no. 148 - p. 152.

12. Murphy, J., Riley, J. P. A modified single solution method for the determination of phosphate in natural waters, // Analytica Chimica Acta, 1962. - v. 27 - p. 31.

13. Olenin, S. Benthic zonation of the Eastern Gotland Basin, Baltic Sea, // Netherlands journal of aquatic ecology, 1997. - v. 30 - no. 4 - p. 265.

14. Soskin, I. M. Long-term variations in hydrological characteristics of the Baltic Sea - Leningrad: Gidrometeoizdat., 1963. - 160 pp.

15. Terziev, F. S., Rozhkov, V. A., Smirnova. A. I. Eds. Hydrometeorology and Hydrochemistry of the Seas in the USSR. Volume III. The Baltic Sea. Issue I. Hydrometeorological Conditions - Saint-Petersburg: Gidrometeoizdat., 1992. - 449 pp.

16. Terziev, F. S., Rozhkov, V. A., Rimsh. E. Ya. Eds. Hydrometeorology and Hydrochemistry of the Seas in the USSR. Volume III. The Baltic Sea. Issue II. Hydrochemical Conditions and Oceanological Bases - Saint-Petersburg: Gidrometeoizdat., 1994. - 435 pp.

Login or Create
* Forgot password?