27 Annales Universitatis Paedagogicae Cracoviensis Studia Naturae, 2: 27–35, 2017, ISSN 2543-8832 DOI: 10.24917/25438832.2.2 Klaudia Świacka, Alicja Michnowska*, Jakub Maculewicz, Izabela Przednowek, Iga Ogrodowczyk, Sebastian Kozic Institute of Oceanography, University of Gdańsk, Gdynia, Poland; *alicja.michnowska@ug.edu.pl Composition of phytoplankton in the Puck Bay and the open Baltic Sea Introduction �e biocenosis of the Baltic Sea is an unusual combination of freshwater and ocean �ora and fauna. �e number of �ora and fauna adapted to life in the brackish water is small, but there may be large quantities of individual species. Compared to the oceans, the food chains in the Baltic Sea are simple. �e number of species reduces from the southern Baltic Sea to the north. �e low salinity of the northern Baltic Sea, the cold winters, and the sea freezing over set challenges for the adaptation of organisms. Due to the slow water turnover, environmental toxins and eutrophying nutrients remain in the Baltic Sea and cause long-term e�ects (Olli et al., 2011). �e Puck Bay (54°40′00″N; 18°35′00″E) is an isolated part of Gulf of Gdańsk, sep- arated by Hel Peninsula. �e Bay has frequently been the subject of marine biological and hydrological research. �is area has speci�c hydrological conditions. Due to the fact that the most of the Puck Bay is shallow, a greater e�ect of wind on the water dy- namics is observed in this area. �us anemobaric conditions in particular contribute to the movement of water masses. In the Puck Bay, a greater correlation between air and surface water temperatures is also observed, where rapid changes of surface water are triggered by changes in air temperature. �erefore, the composition and distribu- tion of phytoplankton in this area di�er signi�cantly during the year (Klekot, 1980; Pliński, Picińska, 1985). Phytoplankton blooms are a poorly studied phenomenon. It is in general connect- ed with seasonal changes of sun irradiance a�ecting water temperature thermocline forming and some other environmental or anthropogenic factors, as local hydrogra- phy, and the increases in�ow of pollutants (Żmijewska et al., 2000). Phytoplankton constitutes an elementary component in aquatic ecosystems. Representing the base of the pyramid of productivity, the understanding and modelling of the aquatic eco- K la ud ia Ś w ia ck a, A lic ja M ic hn ow sk a, J ak ub M ac ul ew ic z, Iz ab el a P rz ed no w ek , I ga O gr od ow cz yk , S eb as tia n K oz ic 28 system is not possible without knowledge of the species composition, productivity, and the biomass of phytoplankton. �ese changes in phytoplankton may re�ect major shi�s in environmental conditions (Olenina et al., 2006). In order to better understand the algal blooms, seasonal monitoring is necessary. Due to natural and methodological reasons, the composition and abundance data on phytoplankton species are highly variable, and consequently, their use as water quality indicators is usually restricted, and mostly chlorophyll a concentrations and primary production are monitored (e.g., SatBałtyk). Moreover, due to development in taxonomical classi�cation and methodology, su�ciently long comparable time series of phytoplankton are rare (Suikkanen et al., 2007). �e aim of this study was to investigate and compare the composition of phyto- plankton and the concentration of photosynthetic pigments on four selected stands located in the inside part of �e Puck Bay and open water of the Baltic Sea. In the present research, quantitative and qualitative methods were used. For qualitative analysis, samples were analysed by microscope (Nicon Eclipse 80i). Every observed individual of phytoplankton was identi�ed to the genus or species lev- el using speci�ed keys for Baltic species of phytoplankton (Pliński, 1980) and noted. Fig. 1. Location of the study area: the open sea (Stands: 1, 2) and the Gulf of Gdańsk (Stands: 3, 4) Material and methods �e main parameters investigated in the present study were the composition of phy- toplankton expressed as the presence of the identi�ed genera or species on each stand C om position of phytoplankton in the P uck B ay and the open B altic S ea 29 and the concentration of photosynthetic pigments: chlorophyll a, b, and c expressed in μg∙L-1. To investigate the composition of phytoplankton, a qualitative method was used. To analyse the concentration of photosynthetic pigments, the quantitative meth- od was used. �e investigation was conducted on a phytoplankton community collected once from the coastal zone in Poland of the open sea (Stands: 1, 2) and the Gulf of Gdańsk (Stands: 3, 4), in July 2017 (Fig. 1). �e plankton samples for qualitative analysis were collected from the surface layer using a phytoplankton net with a diameter of 24.5 cm and 50 µm mesh size. For quantitative analysis, samples were also collected from the surface layer using 5 plastic containers which were �lled with 1 L of water. �e concentration of photosynthetic pigments was measured using a spectropho- tometric method. For quantitative analyses the samples were �ltered (V = 1 L) through MN GF-5 glass �bre �lters and extracted with 5 ml cold 90% acetone and then frozen at a temperature of -20°C for 30 minutes. To remove cell debris and �lter particles, the pigment extract was centrifuged at 10000 rpm for 5 minutes. �e extinction was de- termined at λm 630, 647, 664, and 750 nm with a DU530 UV-VIS spectrophotometer (Beckman) using 1 cm glass cuvette. �e concentration of pigment content was calcu- lated in accordance with Je�rey and Humphrey (1975). �e measurement of photo- synthetic pigment concentration was conducted in triplicate. Results and discussion �e studied phytoplankton community was composed of di�erent representatives of Cyanobacteria, Bacillariophyta, Pyrrophyta, and Chlorophyta (Tab. 1). In total, 17 taxa were observed on all stands, of which 14 were as a genus rank and 3 as a species rank (Fig. 2). �e highest number of phytoplankton representatives was observed in Stand 1, where 12 generas were noted. Aphanizomenon �os-aquae, Chlorella vulgaris, and Navicula sp. were the only taxa noted on every stand. Leptolyngbya sp. and Chloro- coccum sp. were observed only in Stand 1, while Coscinodiscus sp. and Oscillatoria sp. were noted exclusively in Stand 3. �e concentration of chlorophyll a was highest in Stand 4 and reached 2.01 μg∙L-1 (Fig. 3). In the other stands, chlorophyll a content was similar, and reached around 1.5 μg∙L-1. Both concentrations of chlorophyll b and c were the lowest in Stand 2. �e high- est concentration of chlorophyll b was in Stand 1 and reached 0.28 μg∙L-1, while the highest concentration of chlorophyll c was in Stand 3, reaching 0.45 μg∙L-1. However, the concentration of chlorophyll c in Stands 1, 3, and 4 was similar. In all investigated stands, the concentration of chlorophyll a was much higher than the concentration of other types of chlorophyll. K la ud ia Ś w ia ck a, A lic ja M ic hn ow sk a, J ak ub M ac ul ew ic z, Iz ab el a P rz ed no w ek , I ga O gr od ow cz yk , S eb as tia n K oz ic 30 Tab. 1. Individual genera and species of phytoplankton observed on the examined stands: the open sea (Stands: 1, 2) and the Gulf of Gdańsk (Stands: 3, 4) No. Species/Divisions* Stands 1 2 3 4 *Cyanobacteria 1. Aphanizomenon �os-aquae Ralfs ex Bornet & Fla-hault + + + + 2. Dolichospermum sp. + + 3. Leptolyngbya sp. + 4. Microcystis sp. + + 5. Nodularia spumigena Mertens ex Bornet & Flahault + + 6. Oscillatoria sp. + *Pyrrophyta 7. Peridinium sp. + + *Bacillariophyta 8. Chaetoceros sp. + 9. Coscinodiscus sp. + 10. Licmophora sp. + + 11. Navicula sp. + + + + 12. Nitzschia sp. + + 13. Skeletonema sp. + + + *Chlorophyta 14. Chlorella vulgaris Mertens ex Bornet & Flahault + + + + 15. Chlorococcum sp. + 16. Coelastrella sp. + 17. Pediastrum sp. + Total number of taxa 12 9 9 4 In the Baltic Sea during the summer months, cyclically observed phenomenon are the blooms of cyanobacteria, mainly of the order Nostocales. Nodularia spumigena and Aphanizomenon �os-aquae are the most o�en noted species which are the main components of summer blooms (Mazur-Marzec et al., 2012). Diatom blooms during spring and the huge uptake of biogenic compounds cause the decrease of those sub- stances during summer, which makes the environmental conditions favourable for Cyanobacteria. During the de�ciency of biogenic compounds, some species of Cyano- bacteria are capable of �xing atmospheric nitrogen. �e ability of �xing atmospheric nitrogen by some species of Cyanobacteria gives them predominance in the compe- tition for space and environmental resources. �erefore, the heterocytous organisms can rapidly increase their biomass in short periods of time even under conditions of inorganic nitrogen de�ciency (Mazur-Marzec et al., 2012; Wasmund et al., 1998). In Stand 2, the lowest concentration of chlorophyll c and b was observed, which may indicate the lower abundance of Bacillariophyta and Chlorophyta. Out of the C om position of phytoplankton in the P uck B ay and the open B altic S ea 31 groups of algae that were identi�ed, only Chlorophyta contains chlorophyll b in chlo- roplasts, while chlorophyll c is characteristic for Bacillariophyta (Je�rey, Vesk, 1997; Kuczyńska et al., 2015). A high concentration of chlorophyll a and a relatively low concentration of chlorophyll b and c may also indicate the domination of Cyano- bacteria and simultaneously a decrease in diatoms in the Gulf of Gdansk. Moreover, sampling was taken in June when the measured temperature of surface water was of approximately 20°C, which induce blooms of blue-green algae (Fleming, Kaitala, 2006). �e di�erences in the concentration of chlorophyll b between all stands may be connected with the di�erences in the composition of phytoplankton, which is also indicated by present results (Fig. 3; Tab.1). A low concentration of chlorophyll c in Stand 2 may suggest the lower biomass of Bacillariophyta on this site. Fig. 2. Some species of Baltic phytoplankton: a – Aphanizomenon �osaquae Ralfs ex Bornet & Flahault, b – Nodularia spumigena Mertens ex Bornet & Flahault, c – Chlorella vulgaris Beyerinck [Beijerinck] (Source: AlgaeBase – Guiry, Guiry, 2017) K la ud ia Ś w ia ck a, A lic ja M ic hn ow sk a, J ak ub M ac ul ew ic z, Iz ab el a P rz ed no w ek , I ga O gr od ow cz yk , S eb as tia n K oz ic 32 Unfavourable weather conditions (strong wind) probably contributed to the lower number of observed phytoplankton species. In the �rst stand on the end of the Hel Peninsula, the highest numbers of phytoplankton species were observed, which can be connected with the stable conditions during sampling. �e species observed in all stands were A. �os-aquae and C. vulgaris. �ese species are widespread and o�en not- ed in the Gulf of Gdańsk and also in the open water of the Baltic Sea (Mazur-Marzec et al., 2012). Large quantities of Aphanizomenon �os-aquae may contribute to the high concen- tration of chlorophyll a, even in stands characterised by a lower number of observed species of phytoplankton. Many observations suggest that A. �os-aquae produce some compounds that may alter plankton composition and activity, although each strain of this species may have di�erent properties (Mazur-Marzec et al., 2012). �ere are also reports on the ability of these algae to a�ect various aquatic organisms, e.g., mi- croalgae, but every target species may respond di�erently to the allelopathic activi- ty (Keating, 1978; Ikawa et al., 1994; Kearns, Hunter, 2000). Taking into the account potentially harmful e�ects of algal blooms, persistent monitoring programs must be taken into consideration (Żmijewska et al., 2000). Fig. 3. �e concentration of chlorophylls a, b, c on the examined stands: the open sea (Stands: 1, 2) and the Gulf of Gdańsk (Stands: 3, 4) C om position of phytoplankton in the P uck B ay and the open B altic S ea 33 References Fleming, V., Kaitala, S. (2006). Phytoplankton spring bloom intensity index for the Baltic Sea estimated for the years 1992 to 2004. Hydrobiologia, 554(1), 57–65. DOI: 10.1007/s10750-005-1006-7 Guiry, M.D., Guiry, G.M. (2017). AlgaeBase. World-wide electronic publication. Aphanizomenon �osaq- uae Ralfs ex Bornet & Flahault, Nodularia spumigena Mertens ex Bornet & Flahault, Chlorella vulgar- is Beyerinck [Beijerinck]. Galway, Ireland: National University of Ireland, http://www.algaebase.org. Ikawa, M., Haney, J.F., Sasner, J.J. (1994). Inhibition of Chlorella growth by the lipids of cyanobacterium Microcystis aeruginosa. Hydrobiologia, 331, 167–170. DOI: 10.1007/BF00025418 Je�rey, S., Vesk, M. (1997). Introduction to marine phytoplankton and their pigment signatures. In: S. Je�rey, R. Mantoura, S. Wright (eds.). Phytoplankton pigments in oceanography: Guidelines to modern methods. Paris, France: UNESCO Publ., pp. 37–84. Je�rey, S.T., Humphrey, G.F. (1975). New spectrophotometric equations for determining chlorophylls a, b, c1 and c2 in higher plants, algae and natural phytoplankton. Biochemie und Physiologie der P�an- zen, 167(2), 191–194. DOI: 10.1016/S0015-3796(17)30778-3 Kearns, K.D., Hunter, M.D. (2000). Green algal extracellular products regulate antialgal toxin production in a cyanobacterium. Environmental Microbiology, 2, 291–297. Keating, K.I. (1978). Blue-green algal inhibition of diatom growth: transition from mesotrophic to eu- trophic community structure. Science, 199, 971–973. DOI: 10.1046/j.1462-2920.2000.00104.x Klekot, L. (1980). Zatoka Pucka osobliwością hydrologiczną Bałtyku. Oceanologia, 12, 109–123. [In Pol- ish] Kuczyńska, P., Jemioła-Rzemińska, M., Strzałka, K. (2015). Photosynthetic pigments in diatoms. Marine drugs, 13(9), 5847–5881. DOI:10.3390/md13095847 Mazur-Marzec, H., Sutryk, K., Kobos, J., Hebel, A., Hohlfeld, N., Błaszczyk, A., Toruńska, A., Kaczkows- ka, M.J., Łysiak-Pastuszak, E., Kraśniewski, W., Jasser, I. (2012). Occurrence of cyanobacteria and cyanotoxin in the Southern Baltic Proper. Filamentous cyanobacteria versus single-celled picocyano- bacteria. Hydrobiologia, 701, 235–252. DOI: 10.1007/s10750-012-1278-7 Olenina, I., Hajdu, S., Edler, L., Andersson, A., Wasmund, N., Busch, S., Göbel, J., Gromisz, S., Huse- by, S., Huttunen, M., Jaanus, A., Kokkonen, P., Ledaine, I. Niemkiewicz, E. (2006). Biovolumes and size-classes of phytoplankton in the Baltic Sea HELCOM. Baltic Sea Environmental Programme, 106. Olli, K., Klais, R., Tamminen, T., Ptacnik, R., Andersen, T. (2011). Long term changes in the Baltic Sea phytoplankton community. Boreal Environmental Resources, 16, 3–14. Pliński, M. (1980). Glony zatoki Gdańskiej: klucz do oznaczania gatunkow. Gdańsk: Wydawnictwo Uniw- ersytetu Gdańskiego. [In Polish] Pliński, M., Picińska, J. (1985). �e dynamics of seasonal change of the phytoplankton biomass in the Gulf of Gdańsk, Oceanologia, 23, 77–83. Suikkanen, S., Laamanen, M., Huttunen, M. (2007). Long-term changes in summer phytoplankton com- munities of the open northern Baltic Sea. Estuarine, Coastal and Shelf Science, 71, 580–592. DOI: 10.1016/j.ecss.2006.09.004 Wasmund, N., Nausch, G., Matthäus, W. (1998). Phytoplankton spring blooms in the southern Baltic Sea-spatio-temporal development and long-term trends. Journal of plankton research, 20, 1099–1117. DOI: 10.1093/plankt/20.6.1099 Żmijewska, M.I., Niemkiewicz, E., Bielecka, L. (2000). Abundance and species composition of plankton in the Gulf of Gdansk near the planned underwater outfall of the Gdansk-Wschod (Gdansk-East) sewage treatment plant. Oceanologia, 42, 335–357. K la ud ia Ś w ia ck a, A lic ja M ic hn ow sk a, J ak ub M ac ul ew ic z, Iz ab el a P rz ed no w ek , I ga O gr od ow cz yk , S eb as tia n K oz ic 34 Abstract �e Puck Bay is an area characterised by speci�c hydrodynamic conditions that determine the distribution and composition of phytoplankton. �e aim of this study was to investigate the di�erences in the phyto- plankton composition and the content of photosynthetic pigments between the Puck Bay and open Baltic Sea. �e material was collected from four stands which were localised in the inner and outer part of Hel Peninsula. In this study, it has been demonstrated that the composition of individual species of phytoplank- ton di�ered between stands in the inner and outer part of the Puck Bay. �is investigation has also shown that the number of phytoplankton taxa was similar in three stands and it was much lower on the last stand (Stand 4). �e di�erences in the concentration of photosynthetic pigments between all stands have also been observed. Key words: phytoplankton, Puck Bay, Southern Baltic Sea, blooms Received: [2017.07.04] Accepted: [2017.10.26] Struktura fitoplanktonu w Zatoce Puckiej oraz na otwartym Morzu Bałtyckim Streszczenie Zatoka Pucka jest obszarem charakteryzującym się specy�cznymi warunkami hydrodynamicznymi, które determinują rozmieszczenie i skład �toplanktonu. Głównym celem niniejszej pracy było zbadanie różnic w składzie taksonomicznym �toplanktonu oraz zawartości barwników fotosyntetycznych pomiędzy Zatoką Pucką, a otwartymi wodami Morza Bałtyckiego. Materiał zebrano z czterech miejsc zlokalizowanych po wewnętrznej, jak i zewnętrznej, części Półwyspu Helskiego. W pracy wykazano, że istnieją różnice w skła- dzie taksonomicznym �toplanktonu między wewnętrzną i zewnętrzną częścią Zatoki Puckiej. Niniejsza praca pokazała, że liczba taksonów �toplanktonu na stanowiskach 1, 2 i 3 była zbliżona i znacznie wyższa niż na stanowisku 4. Zaobserwowano również różnicę w stężeniach barwników fotosyntetycznych między badanymi stanowiskami. Słowa kluczowe: �toplankton, Zatoka Pucka, Morze Bałtyckie, zakwity Information on the authors Klaudia Świacka In her studies, she focuses on the impact of the Non-steroidal anti-in�ammatory drugs on the Baltic benthic fauna. In current laboratory research, she is investigating the bioaccumulation of diclofenac in Mytilus trossulus tissues. Moreover, she determined the occurrence and concentration of NSAIDs in the Gulf of Gdańsk in the water, sediment, and in the tissues of the organisms collected from di�erent stations. She is also interested in the taxonomy of marine organisms and would like to improve her know- ledge and skills during future investigations. Alicja Michnowska In her research, she is interested in marine ecotoxicology, especially in the matter of marine invertebra- tes. Her main interests include the calibration and modi�cation of methods for the determination of biochemical compounds that can serve as potential biomarkers for environmental condition including genotoxicity, metal contamination, and climate changes. �e aim of her work is to determine a suitable methodology for a multiple biomarker approach usable in ecotoxicologic studies as an environmental diagnostic tool. Jakub Maculewicz �e �eld of his interest is allelopathic interactions of phytoplankton, in particular, of Baltic �lamentous cyanobacteria. He is investigating what in�uences of allelopathic compounds have on those organisms. In C om position of phytoplankton in the P uck B ay and the open B altic S ea 35 his studies, he uses the following innovative methods: analysing pigment content, chlorophyll a �uores- cence, and measuring the rate of photosynthesis to determine what impact allelochemicals have on algae. Izabela Przednowek �e main area of her interest is the biology and ecology of zooplankton. Currently, her research focuses on comparing the species composition of phyoplankton before and a�er the in�ow of water from the North Sea. Such studies have not been conducted previously in the Baltic Sea. Iga Ogrodowczyk She is a marine biology student, and the main research objective of her bachelor’s thesis was to test GST as a marker of neoplasia diseases in bivalve molluscs. Currently, she is trying to expand her knowledge on this subject. She also investigates the spread of neoplasia in bivalve molluscs from the Gulf of Gdańsk. Sebastian Kozic He studies Marine Biology. From the beginning of these studies, he has been interested in investigating zoobenthos. He wrote his undergraduate thesis about polychaetes, and his master thesis will also be about polychaetes. He believes that, in a few years, he will be an expert in polychaetes.