Oceanologia No. 55 (3) / 13

Contents

Invited paper

Papers

Invited paper


Anthropogenic radionuclides 137Cs and 90Sr in the southern Baltic Sea ecosystem
Oceanologia 2013, 55(3), 485-517
http://dx.doi.org/10.5697/oc.55-3.485

Tamara Zalewska1,*, Maria Suplińska2
1Institute of Meteorology and Water Management - National Research Institute, Maritime Branch,
Waszyngtona 42, 81-342 Gdynia, Poland;
e-mail: tamara.zalewska@imgw.pl
*corresponding author
2Central Laboratory for Radiological Protection,
Konwaliowa 7, 03-194 Warsaw, Poland

keywords: 137Cs, 90Sr, southern Baltic

Received 4 January 2013, revised 28 May 2013, accepted 4 June 2013.

Abstract

The radioisotopes of caesium (137Cs) and strontium (90Sr) make the greatest contribution to the radioactivity level due to artificial radionuclides in the Baltic Sea, where the level of 137Cs contamination is higher than in any other part of the world ocean. The main sources of man-made radionuclides are the Chernobyl accident in 1986 and the nuclear weapons tests carried out in the 1950s and 1960s. This study discusses the distribution patterns and trends in activity concentrations of 137Cs and 90Sr recorded in various compartments of the marine environment of the southern Baltic Sea. It is based on an investigation of radioactive substances as part of the Polish National Environmental Monitoring Programme. In 2010 the average concentration of 137Cs in the southern Baltic was 35 Bq m-3, while the level of 90Sr in these waters has remained at much the same level in recent years (ca 8 Bq m-3). The distribution of isotopes in the bottom sediments reflect historical events that can be identified in sediment profiles. The activity concentrations of the caesium isotope are the highest in sediments from the Gulf of Gdansk, whereas the least polluted sediments are found in the Bornholm Basin, in the western part of the southern Baltic. The highest concentrations of 137Cs in benthic plants were measured in the red alga Polysiphonia fucoides: 22.3 Bq kg-1 d.w. in June and 40.4 Bq kg-1 in September. These levels were much higher than those found in the bivalve Mytilus trossulus (7.3 Bq kg-1 d.w.). 137Cs concentrations in fish have decreased in time, reflecting the trends recorded in seawater. In 2010 the respective 137Cs activities in Clupea harengus, Platichthys flesus and Gadus morhua were 4.7, 4.9 and 6.6 Bq kg-1 w.w.

  References ref
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Papers


Activation of the operational ecohydrodynamic model (3D CEMBS) - the hydrodynamic part
Oceanologia 2013, 55(3), 519-541
http://dx.doi.org/10.5697/oc.55-3.519

Lidia Dzierzbicka-Głowacka*, Maciej Janecki, Artur Nowicki, Jaromir Jakacki
Institute of Oceanology, Polish Academy of Sciences,
Powstańców Warszawy 55,81-712 Sopot, Poland;
e-mail: dzierzb@iopan.gda.pl
*corresponding author

keywords: Baltic Sea, 3D model, hydrodynamic model

Received 16 January 2013, revised 16 April 2013, accepted 5 May 2013.

The study was supported by the Polish State Committee of Scientific Research (grants: N N305 111636, N N306 353239). Partial support was also provided by the Satellite Monitoring of the Baltic Sea Environment - the SatBałtyk project funded by the European Union through the European Regional Development Fund contract No. POIG 01.01.02-22-011/09.

Abstract

The paper describes the hydrodynamic part of the coupled ice-ocean model that also includes the ecosystem predictive model. The Baltic Sea model is based on the Community Earth System Model (CESM from NCAR – National Centre for Atmospheric Research). CESM was adopted for the Baltic Sea as a coupled sea-ice model. It consists of the Community Ice CodE (CICE, model version 4.0) and the Parallel Ocean Program (POP, version 2.1). The models are linked through a coupler (CPL7), which is based on the Model Coupling Toolkit (MCT) library. The current horizontal resolution is about 2 km (1/48 degrees). The ocean model has 21 vertical levels and is forced by atmospheric fields from the European Centre for Medium Weather Forecast (ECMWF). A preliminary validation of the hydrodynamic module with in situ measurements and reanalysis from My Ocean (http://www.myocean.eu) has also been done. In the operational mode, 48-hour atmospheric forecasts provided by the UM model from the Interdisciplinary Centre for Mathematical and Computational Modelling of Warsaw University (ICM) are used. The variables presented on the website in real time for a 48-hour forecast are temperature, salinity, currents, sea surface height, ice thickness and ice coverage (http://deep.iopan.gda.pl/CEMBaltic/new_lay/index.php). The embedded model of the marine ecosystem, like ice, is not taken into account in this paper.

  References ref
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Activation of the operational ecohydrodynamic model (3D CEMBS)- the ecosystem module
Oceanologia 2013, 55(3), 543-572
http://dx.doi.org/10.5697/oc.55-3.543

Lidia Dzierzbicka-Głowacka*, Maciej Janecki, Artur Nowicki, Jaromir Jakacki
Institute of Oceanology, Polish Academy of Sciences,
Powstańców Warszawy 55,81-712 Sopot, Poland;
e-mail: dzierzb@iopan.gda.pl
*corresponding author

keywords: Baltic Sea, 3D CEMBS model, ecosystem model, chlorophyll a, phytoplankton, nutrients, zooplankton, oxygen

Received 16 January 2013, revised 16 April 2013, accepted 5 May 2013.

The study was supported by the Polish State Committee of Scientific Research (grants: N N305 111636, N N306 353239). Partial support was also provided by the Satellite Monitoring of the Baltic Sea Environment - the SatBałtyk project funded by the European Union through the European Regional Development Fund contract No. POIG 01.01.02-22-011/09.

Abstract

The paper describes the ecohydrodynamic predictive model - the ecosystem module - for assessing the state of the Baltic marine environment and the Baltic ecosystem. The Baltic Sea model 3D CEMBS (the Coupled Ecosystem Model of the Baltic Sea) is based on the Community Earth System Model, which was adopted for the Baltic Sea as a coupled sea-ice-ecosystem model. The 3D CEMBS model uses: (i) hydrodynamic equations describing water movement, (ii) thermodynamic equations, (iii) equations describing the concentration distribution of chemical variables in the sea, and (iv) equations describing the exchange of matter between individual groups of organisms and their environment that make allowance for the kinetics of biochemical processes.
  The ecosystem model consists of 11 main components: three classes of phytoplankton (small phytoplankton, large phytoplankton represented mainly by diatoms and summer species, mostly cyanobacteria) expressed in units of carbon and chlorophyll a as separate variables, zooplankton, pelagic detritus, dissolved oxygen and nutrients (nitrate, ammonium, phosphate and silicate). In operational mode, 48-hour atmospheric forecasts provided by the UM model from the Interdisciplinary Centre for Mathematical and Computational Modelling of Warsaw University (ICM) are used. All model forecasts are available on the website http://deep.iopan.gda.pl/CEMBaltic/new_lay/index.php. The results presented in this paper show that the 3D CEMBS model is operating correctly.

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Observations of the aerosol particle number concentration in the marine boundary layer over the south-eastern Baltic Sea
Oceanologia 2013, 55(3), 573-598
http://dx.doi.org/10.5697/oc.55-3.573

Steigvile Byčenkiene, Vidmantas Ulevicius*, Nina Prokopčiuk, Dalia Jasinevičiene
Centre for Physical Sciences and Technology,
Savanoriu pr. 231, LT-02300 Vilnius, Lithuania;
e-mail: ulevicv@ktl.mii.lt
*corresponding author

keywords: aerosol number concentration, principal component analysisc, wavelet transform, coastal site, source apportionment

Received 28 January 2013, revised 29 March 2013, accepted 23 April 2013.

This work was partially supported by the Lithuanian-Swiss cooperation programme ‘Researchand development project AEROLIT’ (No. CH-3-SMM-01/08).

Abstract

Continuous measurements of the aerosol particle number concentration (PNC) in the size range from 4.5 nm to 2 µm were performed at the Preila marine background site during 2008–2009. The concentration maxima in summer was twice the average (2650±50 cm-3). A trajectory-based approach was applied for source identification.Potential Source Contribution Function (PSCF) analysis was performed to estimate the possible contribution of long-range and local PNC transport to PNC concentrations recorded at the marine background site. The PSCF results showed that the marine boundary layer was not seriously affected by long-range transport, but that local transport of air pollution was recognized as an important factor. North Atlantic and Sea-Marine type clusters respectively represented 32.1% and 17.9% of the total PNC spectra and were characterized by the lowest PNCs (1080±1340 and 1210±1040 cm-3 respectively) among all clusters.
  Wavelet transformation analysis of 1-h aerosol PNC indicated that while the 16-h scale was a constant feature of aerosol PNC evolution in spring, the longer (∼60-h) scales appeared mainly over the whole year (except June). Principal component analysis (PCA) revealed a strong correlation between PNC and NaCl, highlighting the influence of sea-salt aerosols. In addition, PCA also showed that PNC depended on optical and meteorological parameters such as UVR and temperature.

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UV absorption reveals mycosporine-like amino acids (MAAs) in Tatra mountain lake phytoplankton
Oceanologia 2013, 55(3), 599-609
http://dx.doi.org/10.5697/oc.55-3.599

Dariusz Ficek1,*, Jerzy Dera2, Bogdan Woźniak1,2
1Institute of Physics, Pomeranian University in Słupsk,
Arciszewskiego 22B, Słupsk 76-200, Poland;
e-mail: ficek@apsl.edu.pl
*corresponding author
2Institute of Oceanology, Polish Academy of Sciences,
Powstańców Warszawy 55, 81-712 Sopot, Poland

keywords: phytoplankton absorption spectra, UV absorption, mycosporine-like amino acids, Tatra mountain lakes

Received 12 March 2013, revised 20 May2013, accepted 24 May 2013.

This paper was carried out within the framework of the SatBałtyk project funded by the European Union through European Regional Development Fund, (contract No. POIG.01.01.02-22-011/09 entitled ‘The Satellite Monitoring of the Baltic Sea Environment’). Partial support for this study was also provided by the MNiSW (Ministry of Science and Higher Education) asresearch project N N306 066434 in2008-2011 and also as part of the statutory Research of the Pomeranian University and IO PAN.

Abstract

Enhanced absorption of UV radiation, an effect characteristic of mycosporine-like amino acids (MAAs), is reported in samples of phytoplankton from six lakes in the Tatra Mountains National Park (Poland). It was demonstrated that the mass-specific UV absorption coefficients for the phytoplankton in these lakes increased with altitude above sea level. Based on a comparison with the phytoplankton of Alpine lakes, investigated earlier by other authors (cited in this paper), it may be inferred that the phytoplankton of Tatra mountain lakes produce MAAs, which protect plant cells from UV light, the intensity of which increases with altitude.

  References ref
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Vulnerability assessment of southern coastal areas of Iran to sea level rise: evaluation of climate change impact
Oceanologia 2013, 55(3), 611-637
http://dx.doi.org/10.5697/oc.55-3.611

Hamid Goharnejad*, Abolfazl Shamsai, Seyed Abbas Hosseini
Department of Civil Engineering, Science and Research Branch,
Islamic Azad University, Tehran, Iran;
e-mail: Hgn1982@gmail.com
e-mail: shamsai@sharif.edu
*corresponding author

keywords: climate change impacts,sea-level rise, DWNN, DWANFIS

Received 29 January 2013, revised 20 May 2013, accepted 10 June 2013.

Abstract

Recent investigations have demonstrated global sea level rise as being due to climate change impact. Probable changes in sea level rise need to be evaluated so that appropriate adaptive strategies can be implemented. This study evaluates the impact of climate change on sea level rise along the Iranian south coast. Climatic data simulated by a GCM (General Circulation Model) named CGCM3 under two-climate change scenarios A1b and A2 are used to investigate the impact of climate change. Among the different variables simulated by this model, those of maximum correlation with sea level changes in the study region and least redundancy among themselves are selected for predicting sea level rise by using stepwise regression. Two Discrete Wavelet artificial Neural Network (DWNN) models and a Discrete Wavelet Adaptive Neuro-Fuzzy Inference system (DWANFIS) are developed to explore the relationship between selected climatic variables and sea level changes. In these models, wavelets are used to disaggregate the time series of input and output data into different components.ANFIS/ANN are then used to relate the disaggregated components of predictors and predictand (sea level) to each other. The results show a significant rise in sea level in the study region under climate change impact, which should be incorporated into coastal area management.

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Short-term changes in specific conductivity in Polish coastal lakes (Baltic Sea basin)
Oceanologia 2013, 55(3), 639-661
http://dx.doi.org/10.5697/oc.55-3.639

Roman Cieśliński
Department of Hydrology, Institute of Geography, University of Gdańsk,
Bażyńskiego 4, 80-952 Gdańsk, Poland;
e-mail: georc@univ.gda.pl
*corresponding author

keywords: specific conductivity, short-term changes, increase, decrease, intrusion

Received 5 November 2012, revised 8 January 2013, accepted 29 April 2013.

Abstract

The paper discusses hourly changes in specific conductivity in two lakes and compares them to changes over longer time intervals. The short time intervals between measurements are designed to help assess the course of seawater intrusions. Two lakes on the Polish coast were selected for research purposes - Lakes Gardno and Łebsko. Specific conductivity was measured using an automatic YSI Sontek 6920V2 probe. It was shown that Lake /Lebsko has a permanently elevated specific conductivity, whereas Lake Gardno experiences episodes of fluvial influence.The specific conductivity was shown to change constantly in both lakes, as evidenced by multi-day, daily and hourly data.

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Comparison of the impacts of climate change and anthropogenic disturbances on the El Arish coast and seaweed vegetation after ten years in 2010, North Sinai, Egypt
Oceanologia 2013, 55(3), 663-685
http://dx.doi.org/10.5697/oc.55-3.663

Gihan Ahmed El Shoubaky
Botany Department, Faculty of Science, Suez Canal University,
Ismailia, Egypt;
e-mail: dr_gehan_elshoubaky@yahoo.com

keywords: anthropogenic disturbances, climate change, El Arish coast, El Arish Harbour, El Arish Power Plant, erosion, satellite remote sensing, seaweed vegetation

Received 16 January 2013, revised 3 April 2013, accepted 12 April 2013.

Abstract

Human activities on coasts and climate changes during the past ten years have given rise to considerable shoreline changes along the El Arish coast (the northern coast of the Sinai Peninsula). In the El Arish Power Plant, sediment accretion has reached the tip of the breakwater of the cooling water intake basin, necessitating extensive dredging inside the basin. To the east of El Arish Harbour, the shoreline has been in continuous retreat. The differences between the year 2000 and 2010 in the shoreline along the El Arish coast were determined by analysing satellite images from NOAA-AVHRR images. The analyses revealed erosion and accretion patterns along the coast. The physical parameters showed that the minimum water temperature of 18°C was recorded at site I in winter and that the maximum was 40°C at site II in summer. The latter temperature can be attributed to the effluent discharge of cooling water from the El Arish power plant. Spatial and temporal patterns in the distribution and abundance of macroalgae were measured at four sites (I, II, III and IV) along the El Arish coast.The percentage cover of the successional macroalgae exhibited environmental fluctuations. After ten years, the phytocommunity showed that red and green algae were dominant at the study sites. Significant differences between past and current flora were observed. 39 taxa recorded in 2000 were absent in 2010, while 9 taxa not previously reported were present in 2010. These changes are discussed in the context of possible global warming effects. PERMANOVA showed significant changes (p < 0.001) between sites, seasons, species abundance and macroalgal groupsalong the El Arish coast in 2000 and 2010. The similarity matrix showed a significant difference between the flora in 2010 and that recorded in 2000, indicating poor similarity and changes in species composition among the seasons at the different sites. Most of the algae belonged to the filamentous, coarsely branched and sheet functional form groups.

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Upwelling dynamics in the Baltic Sea studied by a combined SAR/infrared satellite data and circulation model analysis
Oceanologia 2013, 55(3), 687-707
http://dx.doi.org/10.5697/oc.55-3.687

Evgenia Gurova1,*, Andreas Lehmann2, Andrei Ivanov3
1Atlantic Branch of the P. P. Shirshov Institute of Oceanology of the Russian Academy of Sciences (IO RAS),
Pr. Mira 1, 236000 Kaliningrad, Russia;
e-mail: evguruna@gmail.com
*corresponding author
2GEOMAR Helmholtz Centre for Ocean Research,
Kiel, Germany;
e-mail: alehmann@geomar.de
3P. P. Shirshov Institute of Oceanology
Moscow, Russia;
e-mail: ivanoff@ocean.ru

keywords: Baltic Sea, coastal upwelling, MODIS and SAR, images, circulation model

Received 21February 2013, revised 6 May 2013, accepted 11 June 2013.

The Envisat ASAR images used in this study were provided by ESA within the framework of the Envisat AO project C1P.3424, and C1P.8116. This work was supported by 1) the Russian Foundation for Basic Research, grant 12-05-90807 mol_rf_nr, and 2) the Russian Government (grant No. 11.G34.31.0078) for research under the supervision of leading scientists at the Russian State Hydrometeorological University.

Abstract

Data from the space-borne synthetic aperture radar (SAR) aboard the Envisat satellite and MODIS spectroradiometers on board the Terra/Aqua satellites, and the high resolution Sea Ice-Ocean Model of the Baltic Sea (BSIOM) have been used to investigate two upwelling events in the SE Baltic Sea. The combined analysis was applied to the upwelling events in July 2006 along the coasts of the Baltic States, and in June 2008 along the Polish coast and Hel Peninsula. Comparisons indicated good agreement between the sea surface temperatures and roughness signatures detected in satellite imagery and model results. It is shown that BSIOM can simulate upwelling events realistically. The utilization of modelled hydrodynamics and wind stress data together with SAR and SST information provides an extended analysis and deeper understanding of the upwelling processes in the Baltic Sea.
  During the active phase of upwelling when the wind is strong, the resulting coastal jet is controlled by vorticity dynamics related to depth variations in the direction of the flow. Typical upwelling patterns are related to the meandering coastal jet and thus associated with topographic features. The longshore transport of the coastal jet is of the order of 104 m3 s-1, and the offshore transport at the surface is of the order of 103 m3 s-1, which respectively correspond to the total and largest river runoff to the Baltic Sea.

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Red tides of the dinoflagellate Noctiluca scintillans associated with eutrophication in the Sea of Marmara (the Dardanelles, Turkey)
Oceanologia 2013, 55(3), 709-732
http://dx.doi.org/10.5697/oc.55-3.709

Muhammet Turkoglu
Marine Biology Section, Fisheries Engineering Department, Marine Sciences and Technology Faculty, Çanakkale Onsekiz Mart University,
Terzioglu Campus 17100 Çanakkale, Turkey;
e-mail: mturkoglu@comu.edu.tr

keywords: Sea of Marmara, Dardanelles, Noctiluca scintillans, red-tide, eutrophication

Received 16 August 2012, revised 26 November 2012, accepted 4 April 2013.

This study contains the findings of various project such as ‘Turkish Scientific and Technical Research Council (TUBITAK, YDABAG,Project No: 101Y081)’ and Çanakkale Onsekiz Mart University Scientific Research Projects (COMU, BAP, Project No: 2000//22)’. This study was presented as an oral presentation at a Workshop on Algal and Jellyfish Blooms in the Mediterranean and Black Sea organized by the General Fisheries Commission for the Mediterranean (GFCM) on 6-8 October 2010, Istanbul, Turkey. This study was also published as an abstract in the List of Documents and Abstracts of the Workshop.

Abstract

This investigation focused on weekly variations in cell density and volume of the dinoflagellate Noctiluca scintillans between March 2001 and January 2004 in the Dardanelles. March-June and October-December periods were excessive bloom periods. During the bloom periods the density of N. scintillans reached 2.20 × 105 cells L-1 with a volume of 1.32 × 1012 µm3 L-1. In addition to the high surface density, there was an increase in subsurface waters during the blooms. The bloom of N. scintillans, like that of diatom and other dinoflagellate blooms, was associated not only with eutrophication, but also with stable temperatures and salinities.

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Protozoa in a stressed area of the Egyptian Mediterranean coast of Damietta, Egypt
Oceanologia 2013, 55(3), 733-750
http://dx.doi.org/10.5697/oc.55-3.733

Mohamed Moussa Dorgham1,*, Wael Salah El-Tohamy2, Nagwa Elsayed Abdel Aziz3, Ahmed El-Ghobashi2, Jian G. Qin4
1Department of Oceanography, Faculty of Science, Alexandria University,
Alexandria, 21511, Egypt;
e-mail: mdorgham1947@yahoo.com
*corresponding author
2Department of Zoology, Faculty of Science, Mansoura University,
Damietta, Egypt
3National Institute of Oceanography and Fisheries,
Alexandria, Egypt
4School of Biological Sciences, Flinders University,
Adelaide SA, Australia

keywords: environmental conditions, pollution indicators, coastal protozoa, tintinnids, non-tintinnid ciliates

Received 5 July 2012, revised 21 March 2013, accepted 16 April 2013.

Abstract

The Damietta coast is part of the Egyptian Mediterranean coast off the Nile Delta and has recently been polluted as a result of intensive human activities. The environmental parameters and protozoan community in the area were studied biweekly from January to December 2007. The results of the environmental parameters indicated low salinity, oxic and anoxic conditions, high nutrient levels and intensive phytoplankton growth. A total of 69 protozoan species were identified, belonging to Amoebozoa (8 species), Foraminifera (12 species), non-tintinnid ciliates (22 species) and tintinnids (27 species). The numerical density of protozoans was high over the whole area, with annual averages between 8.2 × 103 cells m-3 and 51.4 × 103 cells m-3. Spring was the most productive season for protozoans, but several distinct peaks were observed during the year at the sampling sites. The protozoan groups showed clearly different spatial patterns in both composition and abundance: whereas amoebozoans and non-tintinnid ciliates were dominant in the more polluted areas (sites IV and V), tintinnids dominated in the less polluted areas (sites, I, II and III). Several pollution indicators were recorded:amoebozoans - Centropyxis aculeata, Centropyxis sp., Cochliopodium sp., Difflugia sp.; non-tintinnids - Bursaridium sp., Frontonia atra, Holophrya sp., Paramecium sp., Paramecium bursaria, Vasicola ciliata, Vorticella sp., Strombidium sp.; tintinnids -Favella ehrenbergii, Helicostomella subulata, Leprotintinnus nordgvisti, Tintinnopsis beroidea, Stenosemella ventricosa, Tintinnopsis campanula, T. cylindrica, T. lobiancoi, Eutintinnus lusus-undae.

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Biocontamination of the western Vistula Lagoon (south-eastern Baltic Sea, Poland)
Oceanologia 2013, 55(3), 751-763
http://dx.doi.org/10.5697/oc.55-3.751

Izabela Jabłońska-Barna1,*, Agata Rychter2, Marek Kruk1
1University of Warmia & Mazury, Faculty of Environmental Sciences,
M. Oczapowskiego 5, 10-719 Olsztyn, Poland;
e-mail: ijpb@uwm.edu.pl
*corresponding author
2The State School of Higher Professional Education in Elbląg, Institute of Technology,
Wojska Polskiego 1, 82-300 Elbląg, Poland

keywords: Vistula Lagoon, zoobenthos, biocontamination, alien species

Received 28 January 2013, revised 27 March 2013, accepted 22 May 2013.

This work was supported by Norway grantPNRF82AI.

Abstract

Non-native species exert considerable pressure on aquatic ecosystems; accordingly, they are treated as biopollutants. The Vistula Lagoon, one of the largest brackish water bodies in the Baltic, has become a part of the central corridor for hydrobionts migrating in the direction of western Europe and species expanding in inshore waters. Ten non-indigenous species of benthic invertebrates from five different biogeographical regions have been found in the western part of the Lagoon. Their considerable abundance relative to the numbers and abundance of native species testifies to the high level of biopollution there. The integrated biological contamination index (IBC) calculated for the macrobenthos in the western Vistula Lagoon was 4 andcorresponds to the Lagoon's poor ecological status.

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