Liashenko O. Structure and spatial distribution of phytoplankton in Vyborg Bay in the 21st century // Principy èkologii. 2026. № 1. P. 3‒2. DOI: 10.15393/j1.art.2026.16943

Issue № 1

Original research

pdf-version

Structure and spatial distribution of phytoplankton in Vyborg Bay in the 21st century

Liashenko
Oksana Alexandrovna

PhD, -, Saint-Petersburg brunch of VNIRO, Saint-Petersburg, Makarov Embankment, 26, lyashenko_oa@niorh.vniro.ru

Keywords:
Baltic Sea
Gulf of Finland
Vyborg Bay
phytoplankton
structure
biomass
spatial distribution

Summary: The article presents the results of a study of phytoplankton in the Vyborg Bay of the Baltic Sea. The research was conducted to assess the structure and the level of quantitative development of phytoplankton in the 21st century against the background of large-scale hydraulic engineering works. The results of studies of phytoplankton in the upper, middle and lower parts of the Bay in spatial and temporal aspects in 2000-2024 are presented and analyzed. Samples were taken from the trophogenic layer (three transparency depths along the Secchi disk) every meter, the integral sample was fixed with a Lugol solution with the addition of acetic acid and formalin, and concentrated by filtration. The research showed that, despite similarities in taxonomic composition and phytoplankton structure, different parts of the bay are characterized by specific features of their development. Thus, the maximum values of biomass in the upper part are noted in the middle of summer, while in the middle and lower parts – in the spring period. In general, for Vyborg Bay, the biomass of spring phytoplankton ranged from 0.23 to 12.18 g/m³, dominated mainly by diatoms, in some years also by dinophites. in summer, with biomass values in the range of 0.33–17.66 g/m3, it was mainly based on cyanobacteria. In autumn, the biomass of phitoplancton in the bay ranged from 0.12 to 3.35 g/m³; cyanobacteria dominated in the lower and middle parts of the bay, while diatoms dominated in the upper part. The middle part of the bay, where the largest phytoplankton biomass was observed, can be described as eutrophic. The upper part of the bay receiving waters from the Saimaa Canal, and the lower part, adjacent to the deep-water area of the eastern part of the Gulf of Finland, can be considered as mesotrophic. During the years of research, the quantitative indicators of phytoplankton development and its structure were similar to those observed at the end of the 20th century. The large-scale hydraulic engineering works carried out in the 21st century did not lead to significant changes in quantitative development of phytoplankton and the structure of its dominant communities.

Received on: 22 December 2025

Published on: 01 April 2026

References

Drozdov V. V. Korobkov A. V. The Impact of Dredging Operations on the Environmental Condition of the Vyborg Bay Waters, Uchenye zapiski RGGMU. 2010. No. 12. P. 80–96.

Ecosystem of the Neva River Estuary: Biological diversity and environmental issues. M.: Tovarischestvo nauchnyh izdaniy KMK, 2008. 477 p.

Guidelines for collecting and processing materials in hydrobiological research on freshwater bodies. Phytoplankton and it's production. L., 1981. 32 p.

Kitaev S. P. Basics of limnology for Hydrobiologists and Ichthyologists. Petrozavodsk: Karel'skiy nauchnyy centr RAN, 2007. 395 p.

Lavrent'eva G. M. Mescheryakova S. V. Mickevich O. I. Ogorodnikova V. A. Susloparova O. N. Tereshenkova T. V. Hydrobiological characteristics of Vyborg Bay, Björkezund Strait, Battery Bay, and Luga Bay (Eastern Part of the Gulf of Finland), Finskiy zaliv v usloviyah antropogennogo vozdeystviya. SPb., 1999. P. 211–256.

Makarova S. V. Species composition and quantitative characteristics of phytoplankton, Ekosistemnye modeli. Ocenka sovremennogo sostoyaniya Finskogo zaliva. SPb.: Gidrometeoizdat, 1997. P. 354–365.

Methodology for studying biogeocenoses of inland water bodies. M.: Nauka, 1975. 241 p.

Tereshenkova T. V. Comparative characteristics of summer phytoplankton in Vyborg Bay, Luga Bay, Koporskaya Bay, Björkezund Strait, and the Shallow area of the Eastern Gulf of Finland, Sbornik nauchnyh trudov GosNIORH. 2006. Vyp. 331. T. 1. P. 37–85.

The Gulf of Finland assessment, Reports of the Finnish Environment institute. 2016. Vol. 27. 363 p.

Trifonova I. S. Ecology and Succession of Lake Phytoplankton. L.: Nauka, 1990. 184 p.

Displays: 30;