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Waves, currents and seabed level change in the Port of Gdynia during extreme events

Sapiega P., Zalewska T., Wochna A.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2023

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Vol. 17 No. 3

515--521

EN

The primary purpose of the paper is to identify port areas most exposed to extreme hydrodynamic conditions (waves, sea currents, seabed level change). The results of modelling using SWAN wave model, MIKE 3D model, and reanalysis and measurement data were used in paper. Swell may exceed 0.8 m for winds exceeding 15 m s-1 from the west and south. During extreme conditions, sea currents can reach 0.4 ms-1 in the outer part of the bay adjacent to the port. Port basins do not show changes in the thickness of the seabed for the given maximum values of bottom currents. The most extensive deposition of the seabed and shore sediments (up to 0.04 m) is found on the Gdynia-Oksywie beach adjacent to the port and the approach fairway at the offshore currents. The outer area of the main breakwater is the most exposed to erosive activity (-0.012 m).

2

Budget of 90Sr in the Gulf of Gdańsk (southern Baltic Sea)

Saniewski M., Zalewska T.

Oceanologia

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2018

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No. 60 (3)

256--263

EN

In the period from 2005 to 2011 the major source of 90Sr to the Gulf of Gdańsk was the Vistula river. Its contribution was 99.7% of the total load. The main processes responsible for the decrease in 90Sr activity in the Gulf of Gdańsk were: radioactive decay (87%) and sediment deposition (13%). Average increase in the activity of 90Sr in the Gulf of Gdańsk during the study period was 5.0% (114 GBq), which was almost 2 times higher than the loss of 90Sr due to radioactive decay. In the years 1997-2015, the effective half-life of 137Cs was 9.1 years and that of 90Sr was 50.3 years. Assuming a further decrease in 137Cs and maintaining 90Sr concentrations at present level, it is expected that 90Sr will become the major anthropogenic isotope having impact on the level of radioactivity in the Gulf of Gdańsk.

3

90Sr in Zostera marina from the Gulf of Gdańsk (southern Baltic Sea)

Saniewski M., Zalewska T.

Oceanological and Hydrobiological Studies

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2017

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Vol. 46, No. 1

24--29

EN

90Sr activity was determined in Zostera marina collected in the Gulf of Gdańsk in 2008-2013. 90Sr activity in Z. marina from Jama Kuźnicka and Klif Orłowski range from 0.83 Bq kg-1 d.w. to 3.78 Bq kg-1 d.w. and from 0.68 Bq kg-1 d.w. to 4.95 Bq kg-1 d.w., respectively. The plants collected in spring-summer showed significant differences between 90Sr content in blades - 1.55 Bq kg-1d.w. in 2011 and 2.18 Bq kg-1 d.w. in 2013, and in roots - 7.75 Bq kg-1 d.w. and 11.44 Bq kg-1 d.w., respectively. The reduction in 90Sr concentrations in Z. marina roots to 1-2 Bq kg-1 d.w. in summer resulted from the transport of this element to the young parts of the plant. In autumn and winter, the 90Sr content in the blades of Z. marina was increasing and reached the maximum of 3.77 Bq kg-1 d.w. This could be explained by the process opposite to dilution, related to the biomass reduction and strontium concentration in the plant tissues. Changes in 90Sr concentration in Z. marina tissues are affected by isotope concentration in seawater as well as by salinity, which affects the concentration of Ca2+ - for which Sr2+ is a chemical analogue

4

Temporal changes in Hg, Pb, Cd and Zn environmental concentrations in the southern Baltic Sea sediments dated with210Pb method

Zalewska T., Woroń J., Danowska B., Suplińska M.

Oceanologia

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2015

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No. 57 (1)

32--43

EN

The article presents data on heavy metal – Hg, Pb, Cd and Zn – distribution in the layers of marine sediments from the off-shore areas of the southern Baltic Sea: Gdańsk Deep, SE Gotland Basin and Bornholm Deep. Depth profiles of metal concentrations were converted to time-based profiles using the 210Pb dating method and verified by 137Cs distribution in the vertical profile. The linear sedimentation rates in the Gdańsk Deep and SE Gotland Basin are similar, 0.18 cm yr-1 and 0.14 cm yr-1, respectively, while the region of the Bornholm Deep is characterized by a greater sedimentation rate: 0.31 cm yr-1. Regarding anthropogenic pressure, Gdańsk Deep receives the largest share among the analyzed regions. The maximal metal concentrations detected in this area were Zn – 230 mg kg-1, Pb – 77 mg kg-1, Cd – 2.04 mg kg-1 and Hg – 0.27 mg kg-1. The least impact of anthropogenic pressure was noticeable in SE Gotland Basin. The combination of sediment dating with the analysis of vertical distribution of heavy metals in sediments benefited in the determination of target metal concentrations used in environmental status assessments. Reference values of heavy metal concentrations in marine sediments were determined as: Zn – 110 mg kg-1, Pb – 30 mg kg-1, Cd – 0.3 mg kg-1 and Hg – 0.05 mg kg-1 from the period of minor anthropogenic pressure. Basing on the determined indices: enrichment factor (EF), geoaccumulation indicator (Igeo) and contamination factor (CF) the status of marine environment was assessed regarding the pollution with heavy metals.

5

Sediment deposition and accumulation rates determined by sediment trap and 210Pb isotope methods in the Outer Puck Bay (Baltic Sea)

Szmytkiewicz A., Zalewska T.

Oceanologia

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2014

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No. 56 (1)

85--106

EN

Two methods - in situ sediment trap experiments and an isotopic method based on measurements of 210Pb activities in the sediment cores taken near the traps - were applied for determining sediment deposition and sediment accumulation rates in the eastern part of Puck Bay. The sediment deposition rate (1.67 mm year-1) based on the in situ measurement was comparable with the sediment accumulation rate calculated using the Constant Flux:Constant Sedimentation Rate model for the isotopic method. The age of the sediment layers was determined with the Constant Rate of Supply model; the deepest layers had accumulated around 1900.

6

Anthropogenic radionuclides 137Cs and 90Sr in the southern Baltic Sea ecosystem

Zalewska T., Suplińska M.

Oceanologia

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2013

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No. 55 (3)

485--517

EN

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 Bqkg-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-1w.w.

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Reference organisms for assessing the impact of ionizing radiation on the environment of the southern Baltic Sea

Zalewska T., Suplińska M.

Oceanological and Hydrobiological Studies

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2012

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Vol. 41, No. 4

1-7

EN

Assessing the impact of ionizing radiation on the marine environment requires a well-defined methodology, which includes, among other elements, the analysis of exposure and effects. One of the most important components of the assessment system is the choice of reference organisms specific for the assessed area that fulfill requirements such as radioecological sensitivity, widespread distribution, and amenability to research and monitoring. The following species specific to the southern Baltic Sea that represent diversified ecological niches were proposed as reference organisms. Polysiphonia fucoides was proposed as a representative of macroalgae. Pelagic and benthic fauna were represented by Crangon crangon (crustacean), Saduria entomon (crustacean), Hediste diversicolor (polychaete), and Mytilus trossulus (mollusc). Fish were represented by Clupea harengus (pelagic planctotrophic fish), Gadus morhua (pelagic carnivorous fish), and Platichthys flesus (benthic fish). Activity concentrations of 137Cs were determined in reference biota as well as in seawater, as required for the total dose-rate evaluation, and relevant concentration factors were calculated.

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Bioaccumulation of 137Cs by benthic plants and macroinvertebrates

Zalewska T., Saniewski M.

Oceanological and Hydrobiological Studies

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2011

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Vol. 40, No.3

1-8

EN

137Cs activity concentrations were determined in macrophytes and macrozoobenthic organisms from the southern Baltic Sea. Cesium isotope content was analysed in macroalgae species (green, red and brown algae representatives) and in some species of vascular plants. The analyzed macroinvertebrate organisms included bivalves and a crustacean. Concentration factors (CF) were calculated using the determined 137Cs concentration in the flora and fauna organisms against that in seawater, and the bioaccumulative properties were compared. The study pointed out that the most important factors in the cesium bioaccumulation process occurring in plants are related to morphology. The highest CF values were obtained in algae Polysiphonia fucoides, Ectocarpus siliculosus and Cladophora glomerata. Decidedly lower CF values were observed in the vascular plants and macrozoobenthos representatives.

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Bioaccumulation of gamma emitting radionuclides in red algae from the Baltic Sea under laboratory conditions

Zalewska T., Saniewski M.

Oceanologia

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2011

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No. 53 (2)

631-650

EN

The bioaccumulation ability of radionuclides 5154Mn, 57Co, 60Co, 65Zn, 85Sr, 109Cd, 110mAg, 113Sn, 137Cs and 241Am in two red algae species from the southern Baltic Sea - Polysiphonia fucoides and Furcellaria lumbricalis - was determined under laboratory conditions. P. fucoides demonstrated better bioaccumulative properties towards most of the investigated radionuclides. As a result, P. fucoides can be recommended as a good bioindicator of radioactive environmental pollution. The bioaccumulation of radionuclides in F. lumbricalis was studied during an extended laboratory experiment. The initial extensive uptake of radioisotopes was followed by the rapid removal of cations; in general, concentrations tended to decrease with time. 137Cs displayed a different behaviour, its concentration in the algae increasing over time mainly due to its large ion radius; this is a factor that could be responsible for the stronger mechanical and chemical bonding of Cs+ and that could hamper the movement of ions in both directions.