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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.

2

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

3

Roślinność bentosowa jako indykator stanu środowiska Morza Bałtyckiego

Saniewski M.

Polish Hyperbaric Research

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2013

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nr 1(42)

83--101

PL

Roślinność denna może być wykorzystana do oceny stanu ekologicznego środowiska morskiego poprzez analizy gatunkowe, analizy biomasy oraz określenie wskaźnika stanu makrofitów opartego na stosunku biomasy taksonów pozytywnych do biomasy taksonów negatywnych. Makroglony ze względu na swoją zdolność do bioakumulacji zanieczyszczeń mogą być również wykorzystane do oceny stanu środowiska pod kątem skażeń substancjami niebezpiecznymi. Przykładem może być wykorzystanie fitobentosu do oceny poziomu skażenia wody substancjami radioaktywnymi. Najwyższe średnie aktywności 90Sr pomierzono w tkankach roślin w akwenach, w których stan ekologiczny określony na podstawie makrofitobentosu był najsłabszy.

EN

Phytobenthos can be used to assess the ecological status of the marine environment by the analyses of species, the analyses of biomass and the determination of the macrophyte index based on the ratio of the biomass in negative and positive species. On account of their ability to bioaccumulate, macroalgae can also be used to assess the contamination of the sea by hazardous substances. Phytobenthos is used to assess the level of the radioactive substances in water. The highest average activity of 90Sr was measured in plant tissues in the areas where the ecological status determined using macrophytobentos was by far the poorest.

4

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.

5

Radionuclides in bones of diurnal birds of prey and owls from the eastern Poland

Mietelski J. W., Kitowski I., Gaca P., Frankowska P., Tomankiewicz E., Błażej S., Kierepko R.

Chemia Analityczna

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2008

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Vol. 53, No. 6

821-834