Physical and Chemical Characteristics of the Near-Bottom and Pore Waters, and the Bottom Sediments in the Northeastern Part of the Black Sea Shelf

K. I. Gurov✉, Yu. S. Gurova, N. А. Orekhova

Marine Hydrophysical Institute of RAS, Sevastopol, Russian Federation

✉ e-mail: gurovki@gmail.com

Abstract

Purpose. The investigation is purposed at studying the features of the vertical distribution of geochemical parameters and chemical profile of pore waters in bottom sediments in the coastal zone of the northeastern part of the Black Sea.

Methods and Results. 24 samples of the bottom sediments surface layer were obtained in three cruises on the R/V “Professor Vodyanitsky” in September 2018, July 2019 and August 2021. 5 samples of cores and 9 samples of water from the near-bottom layer were taken in August 2021. The profiles of vertical distribution of oxygen and hydrogen sulfide, the iron oxidized and reduced forms in pore waters, and also oxygen concentration and the degree of oxygen-saturation of the near-bottom waters were studied; the geochemical characteristics of bottom sediments in the surface layer (0–5 cm) and in the cores were also determined. It was noted that the sediments surface layer in the northeastern region was formed by a silty material, the maximum portion of which (83–97%) was recorded in the areas where large rivers of the Krasnodar region flowed into the sea. In the sediments surface layer, the Corg content varied within 0.2–1.9% dry mass. The vertical distribution of Corg in the bottom sediments cores is characterized by a tendency to decrease in its content with depth; its maximum concentrations were observed in the upper (0–4 cm) layer.

Conclusions. It is established that in the area under study, the sediments upper layer is characterized by the aerobic conditions (oxygen penetrated up to 10 mm); in the sediments, the organic matter is oxidized mainly with the participation of iron (Fe(II, III)), that leads to developing the suboxic conditions. In some areas, the redox conditions in the sediments changed from suboxic (the region of Anapa and the area between the cities of Gelendzhik and Tuapse) to anoxic (the region of Novorossiysk and Tuapse), that is conditioned by occurrence of the sulfur reduced forms in the bottom sediments layer. It has been revealed that in the northeastern part of the Black Sea, the distribution of Fe(II, III) in the pore waters of bottom sediments is inversely proportional to the distribution of pH value (the correlation coefficients are –0.68 and –0.73, respectively).

Keywords

bottom sediments, pore waters, oxygen, voltammetry, granulometric composition, organic carbon, Black Sea

Acknowledgements

The study was carried out within the framework of the state assignment on themes FNNN-2021-0004 “Fundamental studies of oceanological processes which determine the state and evolution of the marine environment influenced by natural and anthropogenic factors, based on observation and modeling methods”, FNNN-2021-0005 “Complex interdisciplinary studies of oceanologic processes which determine functioning and evolution of ecosystems in the coastal zones of the Black Sea and the Sea of Azov” and FNNN-2022-0002 “Monitoring of the carbonate system, CO2 and its fluxes in the marine environment of the Black and Azov Seas”, and with the support of the RFBR project No. 20-35-90103.

Original russian text

For citation

Gurov, K.I., Gurova, Yu.S. and Orekhova, N.A., 2023. Physical and Chemical Characteristics of the Near-Bottom and Pore Waters, and the Bottom Sediments in the Northeastern Part of the Black Sea Shelf. Physical Oceanography, 30(4), pp. 454-467.

References

  1. Ovsyany, E.I. and Gurov, K.I., 2016. Research of Organic Carbon and Carbonate Content in the Bottom Sediments of the Crimean Southern Coast Shelf. Physical Oceanography, (1), pp. 60-70. doi:10.22449/1573-160X-2016-1-60-70
  2. Dauvalter, V.A., 2002. Factors of Formation of Chemical Composition of Lake Sediments. Murmansk: MGTU, 75 p. (in Russian).
  3. Gursky, Yu.N., 2003. Geochemistry of Lithohydrosphere of Inland Seas: Vol. 1. Methods of Study and the Processes of Formation of the Chemical Composition of Interstitial Waters in the Bottom Sediments from the Black, Azov, Caspian, Baltic, White and Barents Seas. Moscow: PC GEOS, 331 p. (in Russian).
  4. Rozanov, A.G. and Volkov, I.I., 2009. Bottom Sediments of Kandalaksha Bay in the White Sea: The Phenomenon of Mn. Geochemistry International, 47(10), pp. 1004-1020. doi:10.1134/S001670290910005X
  5. Kuftarkova, E.A., Kovrigina, N.P. and Rodionova, N.Yu., 1999. [Hydrochemical Regime of the Area Adjacent to Omega Bay and Factors That Shape It]. In: MHI, 1999. Ekologicheskaya Bezopasnost' Pribrezhnoy i Shel'fovoy Zon i Kompleksnoe Ispol'zovanie Resursov Shel'fa [Ecological Safety of Coastal and Shelf Zones and Comprehensive Use of Shelf Resources]. Sevastopol: MHI, pp. 175-189 (in Russian).
  6. Mironov, O.G., Kirukhina, L.N. and Alyomov, S.V., 2002. Ecological Characteristic of Kazachva Bay (the Black Sea). Ecology of the Sea, 61, pp. 85-89 (in Russian).
  7. Artamonov, Yu.V., Skripaleva, E.A., Fedirko, A.V., Shutov, S.A., Derjushkin, D.V., Shapovalov, R.O., Shapovalov, Yu.I. and Shcherbachenko, S.V., 2020. Waters Circulation in the Northern Part of the Black Sea in Summer – Winter of 2018. Ecological Safety of Coastal and Shelf Zones of Sea, (1), pp. 69-90. doi:10.22449/2413-5577-2020-1-69-90 (in Russian).
  8. Lavrova, O.Yu., Mityagina, M.I., Sabinin, K.D. and Serebryany, А.N., 2015. Study of Hydrodynamic Processes in the Shelf Zone Based on Satellite Data and Subsatellite Measurements. Sovremennye Problemy Distantsionnogo Zondirovaniya Zemli iz Kosmosa, 12(5), pp. 98-129 (in Russian).
  9. Study of the State of the Ecosystem of the Coastal Part of the Black Sea in the Greater Sochi Area, 2008. Water Industry of Russia: Problems, Technologies, Management, (5), pp. 6-25 (in Russian).
  10. Nemirovskaya, I.A. and Lisitzin, A.P., 2015. Hydrocarbons in Waters and Bottom Sediments of Coastal Areas in the Northeastern Part of the Black Sea. Doklady Earth Sciences, 464(1), pp. 972-978. doi:10.1134/S1028334X15090202
  11. Matishov, G.G., Stepanyan, O.V., Kharkovskiy, V.M. and Soier, V.G., 2014. Current Data on Water Pollution of the Sea of Azov and Black Sea with Petroleum Hydrocarbons. Vestnik SSC RAS, 10(4), pp. 49-52 (in Russian).
  12. Glumov, I.F. and Kochetkov, M.V., eds., 1996. Technogenic Pollution and the Processes of Natural Self-Purification of the Caucasian Zone of the Black Sea. Moscow: Nedra, 502 p. (in Russian).
  13. Korpakova, I.G., Korotkova, L.I., Larin, A.A. and Kornienko, G.G., 2013. Pesticides and Polychlorbiphenyls in the North-Eastern Black Sea Ecosystem by the Data Collected in 1992- 2012. Problems of Fisheries, 14(4), pp. 744-756 (in Russian).
  14. Tikhonova, E.A., 2021. Organic Matter of Bottom Sediments of the Crimean and Caucasian Coasts (Azov and Black Seas). Ecological Safety of Coastal and Shelf Zones of Sea, (3), pp. 52-67. doi:10.22449/2413-5577-2021-3-52-67 (in Russian).
  15. Pavlenko, L.F., Skrypnik, G.V., Anokhina, N.S., Klimenko, T.L., Evseeva, A.I., Ekilik, V.S., Larin, A.A. and Korpakova, I.G., 2013. Pollution of Russian Coastal Waters of the Black Sea by Petroleum Products and Polycyclic Aromatic Hydrocarbons. Problems of Fisheries, 14(4), pp. 785-795 (in Russian).
  16. Chasovnikov, V.K., Chzhu, V.P. and Ocherednik, O.A., 2018. Analysis of Concentrations of Pollutants (Petroleum Products, Phenols, Synthetic Surfactants, Ocps, Pahs, Heavy Metals, etc.) in the Water Column and in the Bottom Sediments of Gelendzhik and Blue Bays. In: A.G. Zatsepin and S.B. Kuklev, eds., 2018. Some Results of Multidisciplinary Coastal Expedition "Black Sea – 2017" at R/V "Ashamba". Moscow: Scientific World, pp. 67-78. doi:10.29006/978-5-91522-472-7-2018.3 (in Russian).
  17. Evseeva, A.I., Korablina, I.V., Gevorkyan, Zh.V., Katalevsky, N.I. and Gorgola, L.G., 2020. Assessment of Water and Bottom Sediment Pollution with Heavy Metals and Arsenic in the Caucasus Region of the Black Sea at the Present Time. Aquatic Bioresources & Environment, 3(3), pp. 7-16. doi:10.47921/2619-1024_2020_3_3_7 (in Russian).
  18. Korablina, I.V., Barabashin, T.O. and Katalevsky, N.I., 2021. Heavy Metals in the Bottom Sediments of the Black Sea Northwestern Shelf in Recent Years. Physical Oceanography, 28(5), pp. 549-566. doi:10.22449/1573-160X-2021-5-549-566
  19. Eremeev, V.N., Konovalov, S.K. and Romanov, A.S., 1998. The Distribution of Oxygen and Hydrogen Sulfide in Black Sea Waters during Winter-Spring Period. Physical Oceanography, 9(4), pp. 259-272. doi:10.1007/BF02522712
  20. Weiss, R.F., 1970. The Solubility of Nitrogen, Oxygen and Argon in Water and Seawater. Deep Sea Research and Oceanographic Abstracts, 17(4), pp. 721-735. doi:10.1016/0011- 7471(70)90037-9
  21. Orekhova, N.A. and Konovalov, S.K., 2009. Polarography of the Bottom Sediments in the Sevastopol Bay. Physical Oceanography, 19(2), pp. 111-123. doi:10.1007/s11110-009- 9038-6
  22. Luther III, G.W., Glazer, B.T., Ma, Sh., Trouwborst, R.E., Moore, T.S., Metzger, E., Kraiya, Ch., Waite, T.J., Druschel, G. [et al.], 2008. Use of Voltammetric Solid-State (Micro)Electrodes for Studying Biogeochemical Processes: Laboratory Measurements to Real Time Measurements with an in Situ Electrochemical Analyzer (ISEA). Marine Chemistry, 108 (3-4), pp. 221-235. doi:10.1016/j.marchem.2007.03.002
  23. Taillefert, M., Bono, A.B. and Luther, G.W., 2000. Reactivity of Freshly Formed Fe(III) in Synthetic Solutions and (Pore)Waters: Voltammetric Evidence of an Aging Process. Environmental Science & Technology, 34(11), pp. 2169-2177. doi:10.1021/es990120a
  24. Ljutsarev, S.V., 1986. The Determination of Organic Carbon in the Sea Bottom Sediments by Means of Dry Oxidation. Oceanology, 26(4), pp.704-708 (in Russian).
  25. Zabegaev, I.A., Shul'gin, V.F. and Orekhova, N.A., 2021. Application of Instrumental Methods for Analysis of Bottom Sediments for Ecological Monitoring of Marine Ecosystems. Scientific Notes of V.I. Vernadsky Crimean Federal University. Biology. Chemistry, 7(73), pp. 242-254 (in Russian).
  26. Kostyleva, A.V., 2015. Distribution of Dissolved Organic Carbon in River Mouth Areas of the Greater Sochi Region (North-Eastern Part of the Black Sea). Oceanology, 55(2), pp. 200- 206. doi:10.1134/S0001437015020071
  27. Makkaveev, P.N. and Zavyalov, P.O., 2018. Runoff of Small and Medium Rivers of the Russian Black Sea Coast and Its Influence on Water Characteristics. In: A. P. Lisitzin, ed., 2018. The Black Sea System. Moscow: Scientific World, pp. 287-322. doi:10.29006/978- 5-91522-473-4.2018 (in Russian).
  28. Orekhova, N.A., 2021. Nutrients Dynamics in the Surface Waters of the Black Sea. Physical Oceanography, 28(6), pp. 660-676. doi:10.22449/1573-160X-2021-6-660-676
  29. Ovsyanyi, E.I., Konovalov, S.K., Kotel'yanets, E.A. and Mitropol'skii, A.Y., 2015. Organic Carbon and Carbonates in the Recent Bottom Sediments of the Kerch Strait. Geochemistry International, 53(12), pp. 1123-1133. doi:10.1134/S0016702915120071
  30. Gurov, K. and Konovalov, S., 2020. Bottom Sediments and Their Properties in the Сrimea Coastal Regions. In: SWS Scholarly Society, 2020. 20th International Multidisciplinary Scientific GeoConference SGEM 2020. Sofia: STEF92 Technology. Volume 20, iss. 3.1, pp. 815-822. doi:10.5593/sgem2020/3.1/s15.105
  31. Aleskerovа, A.A., Kubryakov, A.A., Goryachkin, Yu.N. and Stanichny, S.V., 2017. Propagation of Waters from the Kerch Strait in the Black Sea. Physical Oceanography, (6), pp. 47-57. doi:10.22449/1573-160X-2017-6-47-57
  32. Kurinnaya, Yu.S., Gurov, K.I., Zabegaev, I.A. and Orekhova, N.A., 2022. Redox Conditions and Characteristics of Bottom Sediments in the Bays of the Sevastopol Region. Ecological Safety of Coastal and Shelf Zones of Sea, (1), pp. 42-54. doi:10.22449/2413-5577-2022-1- 42-54
  33. Rickard, D. and Luther III, G.W., 2007. Chemistry of Iron Sulfides. Chemical Reviews, 107(2), pp. 514-562. doi:10.1021/cr0503658
  34. Orekhova, N.A. and Konovalov, S.K., 2018. Oxygen and Sulfides in Bottom Sediments of the Coastal Sevastopol Region of Crimea. Oceanology, 58(5), pp. 679-688. doi:10.1134/S0001437018050107
  35. Zatsepin, A.G., Kremenetskiy, V.V., Stanichny, S.V. and Burdyugov, V.M., 2010. Black Sea Basin-Scale Circulation and Mesoscale Dynamics under Wind Forcing. In: A. V. Frolov and Yu. D. Resnyansky, eds., 2010. Modern Problems of Ocean and Atmosphere Dynamics: The Pavel S. Lineykin memorial volume. Moscow: Triada LTD, pp. 347-368 (in Russian).
  36. Belkina, N.A., 2014. [Changes in the Redox State of Lake Bottom Sediments under the Influence of Anthropogenic Factors (On the Example of Ladoga and Onega Lakes)]. Society. Environment. Development, 3(32), pp. 152-158 (in Russian).

Download the article (PDF)