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Wyświetlanie 1-10 z 10
Tytuł:
Is iron a limiting factor of Nodularia spumigena blooms?
Autorzy:
Paczuska, L.
Kosakowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/48305.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
pigment
Cyanoprokaryota
trace element
alga
chlorophyll a
Nodularia spumigena
bloom
Baltic Sea
growth
Opis:
It is well known that a deficiency of iron, a trace element essential to every living organism, limits the growth of algae and cyanobacteria. Nodularia spumigena Mertens is a blue-green algae species inhabiting the Baltic region that often forms toxic blooms. The aim of the study was to assess the growth of the toxic cyanobacteria with respect to iron bioavailability. The measured growth parameters were the numbers of cells (optical density), chlorophyll a and pheopigment a concentrations. The iron concentrations used ranged from 10−7 to 10−4 mol dm−3. Under iron stress conditions (< 5 × 10−7 mol dm−3), growth inhibition, gradual pigment decay and cell mortality were observed. However, enriching the medium with complexing factors like citric acid and EDTA significantly stimulated the growth rate and chlorophyll a production. The citric acid – EDTA – Fe (5 × 10−7 mol dm−3) complex was demonstrably effective in stimulating the rate of cell division. Starting with 10−6 mol dm−3, the higher the iron(III) concentration used in the media, the more intensive the growth of the cyanobacteria populations. This was most rapid in the presence of high iron concentrations (10−4 mol dm−3), regardless of the presence of complexing agents. It appears that the growth of toxic cyanobacteria N. spumigena, and thus also its ability to form blooms, may well depend on iron availability in the environment.
Źródło:
Oceanologia; 2003, 45, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Element enrichment and provenance of the detrital component in Holocene sediments from the Western Black Sea
Autorzy:
Dekov, V.M.
Darakchieva, V.Y.
Billstrom, K.
Garbe-Schonberg, C.D.
Kamenov, G.D.
Gallinari, M.
Dimitrov, L.
Ragueneau, O.
Kooijman, E.
Powiązania:
https://bibliotekanauki.pl/articles/2079273.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
trace element concentration
isotope analysis
enrichment factor
Holocene sediment
catchment area
geochemical analysis
Black Sea
Opis:
Concentrations of a large set of major and trace elements, and Sr, Nd and Pb isotope ratios were measured in Holocene sediments cored in the western deep Black Sea in order to unravel: (1) the controls of element enrichment, and (2) sources of the detrital component. The transition of the basin from oxic to euxinic resulted in enrichment or depletion in a number of elements in the deep-sea sediments. Authigenic Fe enrichment appears to depend on the amount of Fe mobilized from the sediment through the benthic redox shuttle mechanism and free H2S in the water column (degree of “euxinization”). Manganese enrichment is controlled by diagenetic reactions within the sediment: the dissolution of Mn minerals, Mn2+ diffusion upward and reprecipitation. Barium enrichment is also controlled by diagenetic reactions, sulfate reduction and methanogenesis, that take place above and below the sulfate-methane transition, respectively. The major part of V, Co, Ni, Cu, Zn, Cr, Mo, Cd and Sb is inferred to have co-precipitated with Fe in the euxinic deep waters and to have been incorporated into authigenic Fe-sulfides. Basin reservoir effect additionally influences the Mo enrichment. The U enrichment is interpreted to have a different origin in the two organic-rich stratigraphic units (II and I). It is inferred to be: (i) at the expense of the U inventory of the deepwater pool and a result of inorganic reduction of U at euxinic conditions in the lower Unit II; and (ii) at the expense of the U inventory of the surface water pool and a result of biogenic uptake and transfer to the sediment by the plankton in the upper Unit I. The high field strength elements are closely linked to the detrital component and their depletion in the organic-rich sediments reflects a dilution of the detrital component by the biogenic one. The enrichments of REE, Sn and Th are likely controlled by adsorption on clay minerals. Sr-Nd-Pb isotope compositions of the alumino-silicate component of the studied sediments are relatively uniform. They are most likely controlled by riverine suspended matter supplied mainly in the NW Black Sea (Danube Delta) and transported southward by marine currents, and to a lesser degree by suspended matter from the small rivers draining SE Bulgaria and NW Turkey. Wind-blown dust from the Sahara Desert appears to have a minor contribution to the alumino-silicate component of the sediments. The slight shift in the Pb isotopes in Unit I upper layers is possibly caused by the addition of anthropogenic Pb.
Źródło:
Oceanologia; 2020, 62, 2; 139-163
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interlaboratory analytical performance studies; a way to estimate measurement uncertainty
Autorzy:
Lysiak-Pastuszak, E.
Powiązania:
https://bibliotekanauki.pl/articles/48992.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
marine environment
nutrient
chlorinated organic compound
quality assurance
trace metal
sea water
analytical chemistry
monitoring
Opis:
Comparability of data collected within collaborative programmes became the key challenge of analytical chemistry in the 1990s, including monitoring of the marine environment. To obtain relevant and reliable data, the analytical process has to proceed under a well-established Quality Assurance (QA) system with external analytical proficiency tests as an inherent component. A programme called Quality Assurance in Marine Monitoring in Europe (QUASIMEME) was established in 1993 and evolved over the years as the major provider of QA proficiency tests for nutrients, trace metals and chlorinated organic compounds in marine environment studies. The article presents an evaluation of results obtained in QUASIMEME Laboratory Performance Studies by the monitoring laboratory of the Institute of Meteorology and Water Management (Gdynia, Poland) in exercises on nutrient determination in seawater. The measurement uncertainty estimated from routine internal quality control measurements and from results of analytical performance exercises is also presented in the paper.
Źródło:
Oceanologia; 2004, 46, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Can multiple fish farms be integrated within a semi-enclosed bay without causing acute ecosystem degradation?
Autorzy:
Puhr, K.
Pikelj, K.
Fiket, Z.
Powiązania:
https://bibliotekanauki.pl/articles/47450.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
fish farm
sea bass
Dicentrarchus labrax
sea bream
Sparus aurata
environmental factor
organic matter
trace element
hydrodynamics
sediment
Opis:
The current study explores the possibility that multiple fish farms (FFs) containing sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) can be successfully integrated within a semi-enclosed bay in the Croatian Adriatic. The research focuses on determining principal environmental factors (EFs) that control the integration and attempts to estimate their individual and synergic ability to influence deposition and removal of organic matter (OM) and trace elements (TE) from the system. The complexity of the designated tasks demanded a comprehensive number of various datasets and samples to be used in the analysis. The ADCP data revealed strong wind induced currents forming within the research domain resulting in high system flushing efficiency (3.5—6 days). The sediment samples from all stations contained relatively inert minerals which contributed to overall low OM and TE concentrations and very limited variability found across the entire bathymetric range. The thermal advection effect recorded at two stations was attributed to specific seabed topography and the hydrodynamic response formed during Maestral wind episodes. The results indicate that a successful integra- tion of four FFs has taken place within the research site (semi enclosed bay), and that the key EFs responsible for its success are strong wind induced hydrodynamics, favorable seabed topography and sediment mineral composition. The synergy of the principal EFs that formed within the system was found to have an attenuating effect regarding FFs chemical influence (OM and TE) and an amplifying one regarding spatial footprint which extended to = 2000 m distance.
Źródło:
Oceanologia; 2017, 59, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The inflow of 234U and 238U from the River Odra drainage basin to the Baltic Sea
Autorzy:
Skwarzec, B.
Tuszkowska, A.
Borylo, A.
Powiązania:
https://bibliotekanauki.pl/articles/47957.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
Baltic Sea
Odra River
Polska
Szczecin Lagoon
concentration
drainage basin
inflow
natural radionuclide
radionuclide
trace element
uranium
water sample
Opis:
In this study the activity of uranium isotopes 234U and 238U in Odra river water samples, collected from October 2003 to July 2004, was measured using alpha spectrometry. The uranium concentrations were different in each of the seasons analysed; the lowest values were recorded in summer. In all seasons, uranium concentrations were the highest in Bystrzyca river waters (from 27.81±0.29 Bq m−3 of 234U and 17.82±0.23 Bq m−3 of 238U in spring to 194.76±3.43 Bq m−3 of 234U and 134.88 ± 2.85 Bq m−3 of 238U in summer). The lowest concentrations were noted in the Mała Panew (from 1.33±0.02 Bq m−3 of 234U and 1.06±0.02 Bq m−3 of 238U in spring to 3.52 ± 0.05 Bq m−3 of 234U and 2.59 ± 0.04 Bq m−3 of 238U in autumn). The uranium radionuclides 234U and 238U in the water samples were not in radioactive equilibrium. The 234U/238U activity ratios were the highest in Odra water samples collected at Głogów (1.84 in autumn), and the lowest in water from the Noteć (1.03 in winter and spring). The 234U/238U activity ratio decreases along the main stream of the Odra, owing to changes in the salinity of the river’s waters. Annually, 8.19 tons of uranium (126.29 GBq of 234U and 100.80 GBq of 238U) flow into the Szczecin Lagoon with Odra river waters.
Źródło:
Oceanologia; 2010, 52, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mineralogical and chemical composition of the mud fraction from the surface sediments of Sharm Al-Kharrar, a Red Sea coastal lagoon
Autorzy:
Basaham, A.S.
Powiązania:
https://bibliotekanauki.pl/articles/48257.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
Sharm Al-Kharrar
mineralogical composition
trace element
chemical composition
mud fraction
Red Sea
surface sediment
tropical marine habitat
coastal lagoon
Opis:
Interaction between continental and marine end-members gives rise to the natural biogeochemical processes in Sharm Al-Kharrar, a lagoon in the arid Red Sea region. Twenty-nine surface sediment samples were collected from the area and their mud fraction analysed for grain size, OC, CaCO3, mineralogy and elemental composition. The mud fraction consisted of a mixture of siliciclastic/calcareous materials, dominated by silt size materials and characterised by low OC (average 0.71% ±0.13); CaCO3 varied widely, with an average of 45% ±18. Concentrations of Al, Fe, Mn, Cu, Ni, Cr, V and Ba showed a wide range of variation throughout the Sharm. The results were normalised to Al and subjected to cluster analysis in order to examine the relations between the mineralogy and the elemental composition. The contents of Al, Fe, Mn, Cu, Ni, Cr, V and Ba appeared to be influenced by the mixing of the two end-members in addition to the physiochemical processes associated with the mixing between episodic freshwater flooding and seawater. Zn was the single element that showed a slight departure from the mixing model.
Źródło:
Oceanologia; 2008, 50, 4; 557-575
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocean acidification and marine microorganisms: responses and consequences
Autorzy:
Das, S.
Mangwani, N.
Powiązania:
https://bibliotekanauki.pl/articles/49020.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
acidification
ocean
water microorganism
climate change
ecosystem
marine environment
primary production
trace gas
nitrogen fixation
community composition
organic matter
enzyme activity
Źródło:
Oceanologia; 2015, 57, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Baltic Sea - an example of how to protect marine coastal ecosystems
Autorzy:
Nehring, D.
Powiązania:
https://bibliotekanauki.pl/articles/48329.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
marine environment
crude oil
inorganic nutrient
environment
trace metal
ecosystem protection
contamination
chlorinated hydrocarbon
HELCOM Baltic Monitoring Programme
Baltic Sea
eutrophication
Opis:
The Baltic Sea covers an area of 415 000 km2. A typical brackish sea, it is very sensitive to anthropogenic activities. Inorganic nutrients, trace metals, chlorinated hydrocarbons and crude oil products are contaminants studied in the Baltic Monitoring Programme of HELCOM. The data collected by the riparian countries forms the basis for the periodic assessments of the state of the marine environment of the Baltic Sea Area produced by HELCOM every five years. Since 1992 marine nature conservation has been part of the HELCOM convention. According to the third status report issued in 1996, it was the first time that HELCOM could strike a positive balance with regard to the decreasing environmental load. This is also reflected in lower concentrations of harmful substances in fish, marine mammals and seabirds in the Baltic Sea Area. The reasons for this progress are the protective actions initiated by HELCOM and the economic collapse in some of the former East Bloc countries, the latter resulting in an abrupt fall in industrial and agricultural production. Although the restoration of the Baltic ecosystem has only just begun, the protective measures introduced to achieve this aim can serve as an example of how to solve similar problems in other semi-enclosed basins and shelf seas.
Źródło:
Oceanologia; 2001, 43, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Metal pollutants and radionuclides in the Baltic Sea - an overview
Autorzy:
Szefer, P.
Powiązania:
https://bibliotekanauki.pl/articles/48734.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
fish
trace element
metal pollutant
suspended matter
plankton
zoobenthos
sea water
Baltic Sea
biomonitor
chemical balance
marine mammal
radionuclide
pollution
metal
Baltic ecosystem
Opis:
This overview presents in detail the state of knowledge of the abilities of various components of the Baltic Sea environment to accumulate trace elements and radionuclides. Particular components of the Baltic ecosystem (abiotic and biotic) are considered as potential monitors of pollutants. The use of seaweeds, e.g. Fucus vesiculosus or Zostera marina is recommended, also molluscs, e.g. Mytilus edulis, for biomonitoring surveys of metal pollutants and radionuclides in the Baltic Sea. However, several requirements need to be met if results are to be reliable. Since metal levels and radionuclide activities in the growing tips of F. vesiculosus reflect exclusively the levels of their dissolved species in the ambient seawater, this alga is very useful for monitoring dissolved species of metal pollutants and radioisotopes in the Baltic ecosystem. In contrast, M. edulis, a filter feeder is an appropriate tool for monitoring trace elements occurring in both chemical forms, i.e. dissolved and suspended species. Therefore, full information on the bioavailability and toxicity of heavy metals (depending on their chemical speciation) as pollutants of the Baltic Sea can be obtained if at least two biomonitoring organisms are applied simultaneously, e.g. F. vesiculosus and M. edulis. Moreover, the data matrix can be interpreted more accurately if not only trace element but also macroelement concentrations (Ca, Mg, Na, K) in these two representatives of Baltic phytoand zoobenthos are taken into consideration; this point requires special attention. Two coastal species of fish, i.e. Zoarces viviparus and Perca fluviatilis, are good biomonitors of metallic contaminants, so their use as sentinels is recommended. The budgets of chemical elements and the ecological status of the Baltic Sea are presented. Several ‘blacksp ots’, e.g. large estuaries and seaport towns, heavily polluted by trace elements, are identified in the Baltic Sea and other enclosed seas such the Mediterranean and the BlackS eas. Of these seas, the Baltic is the most heavily loaded with trace elements and organic pollutants. The overview identifies gaps in our environmental knowledge of the Baltic Sea, and sets out possible priorities, key areas or strategies for future research.
Źródło:
Oceanologia; 2002, 44, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Relationship between biomarker responses and contaminant concentration in selected tissues of flounder (Platichthys flesus) from the Polish coastal area of the Baltic Sea
Autorzy:
Napierska, D.
Podolska, M.
Powiązania:
https://bibliotekanauki.pl/articles/48205.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
Platichthys flesus
mussel
liver tissue
Baltic Sea
polychlorinated biphenyl
organochlorine pesticide
biomarker
trace metal
contaminant gradient
flounder
fish
muscle
Polish coastal area
Gdansk Gulf
Opis:
Previous studies in the Gulf of Gdańsk discussed the responses of selected enzymatic biomarkers to the contaminant gradient in fish and mussels. In the present study, flounder muscle and liver tissues were analyzed for polychlorinated biphenyls (PCB congeners: 28, 52, 101, 118, 138, 153 and 180), organochlorine pesticides (HCHs, HCB and DDTs), and trace metals (Pb, Cd, Zn, Cu, Hg, Cr). An attempt was made to identify the relationship between the measured enzymatic biomarker responses (cholinesterases, malic enzyme, isocitrate dehydrogenase, glutathione S-transferase) and contaminant concentrations in selected flounder tissues. The observed differences in enzymatic biomarker levels suggest that chronic exposure to low-concentration mixtures of contaminants may be occurring in the studied area. However, no conclusive evidence was found of a clear link between the biomarker responses and contaminant concentrations in flounder tissues.
Źródło:
Oceanologia; 2008, 50, 3; 421-442
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-10 z 10

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