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EN
The concentrations of nonylphenol and 4-tert-octylphenol were measured in surface waters in the Gulf of Gdansk coastal zone (summer 2010). The mean concentration in the samples of subsurface water were 34.49 ng dm-3 (nonylphenol) and 3.04 ng dm-3 (4-tert-octylphenol). The highest nonylphenol concentrations were detected in the samples of subsurface water collected from the Sea Boulevard (Gdynia) while the highest concentrations of 4-tert-octylphenol were found in the yacht harbor Marina Gdynia, and in the Kacza and Gizdebka rivers. A significant enrichment (13-45 times) of 4-tert-octylphenol was observed in the surface microlayer of water. These levels exceeded the predicted no effect concentration by 2-9 times.
EN
The possibilities of using newly developed nano- and micro-thin films in biomedicine are intensively studied at the present time. Many research institutions are looking for ways to evaluate mechanical properties of these films. One of the most important and frequently studied characteristics is practical adhesion. A very important method for evaluating the practical adhesion strength is scratch test. Often, however, the research teams use a method based on the disunity evaluation of adhesion of biocompatible surface layer. This makes the quantitative comparison of research results impossible. We designed and tested new evaluation method and procedure based on international standards in order to eliminate these problems. This article is aimed at showing the new possibility of using established standards for evaluating adhesion of nano- and micro-thin biocompatible films and at showing the application of the standards to evaluate the often studied DLC biocompatible layers. The thickness of the film was 470 nm. As a substrate a titanium alloy Ti6Al4V was used.
EN
The potential effect of an increase in ultraviolet radiation on organic matter in the sea surface microlayer and subsurface bulk seawater was evaluated in spring during three sampling periods in 1997, 1998, and 2000. The phytoplankton concentration is high in the water of the southern Baltic during this period. The results of temporal changes in chlorophyll a, phaeopigments, and oxygen concentrations were taken into account. An inhibitory effect (expressed as a decline in chlorophyll a concentrations) on biological processes in the sea surface microlayer as well as in the subsurface layer occurred around noon and in the early afternoon. High levels of ultraviolet radiation intensified chlorophyll a reduction. The measurements conducted in the microlayer and the subsurface layer indicated the possibility of photodamage to phytoplankton under natural conditions when there is an excessive increase of UV-B radiation in comparison to PAR. A significant increase in the phaeophytin a concentration and a decrease in the chlorophyll a concentration was observed at noon when the UV-B/PAR ratio was high.
EN
The processes occurring at the marine water - atmosphere boundary layer and involving selected important components of our environment are discussed. Special attention is focused on the specific role of the marine water surface microlayer in transfer of those components, properties of aerosols, fundamental question of CO2 absorption/desorption balance and environmental conditions enabling rc-cmission of mercury from marine water into the atmosphere. Simple laboratory experiments on CO2 absorption from atmosphere and desorption of CO2 from marine water arc shown as an initial point for any wider discussion on the global carbon budget. The emission of mercury to the atmosphere is considered to be promoted by the solar radiation. Under strong solar radiation the ability of organic matter to reduce these ions is enhanced thus making the emission more effective. The phenomenon observed seems to be confirmed by the analysis of the data for months of low and high radiation intensity. A significant role of atmospheric iron in eutophication of southern Baltic is emphasized. Concentration of this clement in dry and wet deposition is, however, too low to prevent limitation of phytoplankton growth in marine water.
PL
Praca prezentuje wyniki badań i główne hipotezy naukowe skupione wokół procesów występujących na granicy wody i atmosfery. Główny nacisk położono na określenie roli mikrowarstwy powierzchniowej morza w przenoszeniu substancji chemicznych w postaci gazów i aerozoli pomiędzy oboma ośrodkami. W wyniku badań pojawiły się fundamentalne pytania o zachwianą równowagę pomiędzy absorpcją i desorpcją CO2 na granicy warstw oraz rc-cmisję rtęci Hg(0) z wody do atmosfery. Eksperymenty laboratoryjne nad absorpcją CO, z atmosfery i desorpcją CO2 z wody morskiej stały się ważną przesłanką do szerokiej dyskusji naukowej o globalnym budżecie węgla. Re-emisja rtęci do atmosfery to problem przejawiający się silnym oddziaływaniem radiacji słonecznej i zdolności materii organicznej do redukcji jonów Hg(II). Problem efektywnej re-emisji rtęci do atmosfery został zaprezentowany jako złożony zespół uwarunkowań dynamicznych, fotochemicznych i biologicznych w transformacji Hg(II) do Hg(0). Rola żelaza atmosferycznego rozpatrywana jest na tle eutrofizacji wód powierzchniowych południowego Bałtyku. Depozycja tego elementu w aerozolach i w opadach deszczy jest prawdopodobnie zbyt mała, aby stymulować rozwój fitoplanktonu i wzmagać poziom troficzności morza.
5
Content available remote Adenosine triphosphate in the marine boundary layer in the southern Baltic Sea
EN
Changes in adenosine triphosphate (ATP) concentration were measured in the offshore and coastal waters of the Gdansk Basin in spring. As regards the vertical distribution, it was found that high ATP concentrations occurred mainly in the euphotic layer (above the thermocline) and near the bottom (below the halocline). The high concentrations of ATP in the euphotic layer resulted from primary and secondary production, while the other maximum was due to the presence of bacteria actively degrading organic matter. Changes in ATP concentration in the euphotic layer were closely correlated with the phase of the day. An increase in ATP concentrations in the surface microlayer was observed in the evening and at night, probably as a result of heterotroph proliferation. During daylight, ATP production was inhibited by increasing radiation, hence its concentrations in the sea surface microlayer were considerably lower. Strong winds exerted a significant influence on ATP concentrations in the surface microlayer and in the subsurface water. Windstress depressed ATP concentrations. The biomass of living microorganisms in the microlayer was comparable with the microbiomass beneath the halocline.
EN
Short-term measurements of nutrient and DOC concentrations and suspended matter (particles, chlorophyll a, phaeophytin, algae and ATP concentrations) carried out in seawater layers of varying thickness (10, 90, 250 žm and the underwater layer - 15 cm depth) in spring form the basis for a discussion of the diurnal fluctuations of nutrient and suspended organic matter concentrations. Quantitative and qualitative differences in the composition of neuston species were recorded in selected sub-layers of the chemically stratified sea surface microlayer. The non-linear regression equation was applied in a mathematical model of the diurnal fluctuations of nutrients and organic matter. Two maxima and two minima were found in the diurnal cycle of nutrient concentrations and organic suspensions in sub-layers of different thickness selected from the sea surface. The first maximum, expressed by the proliferation of phytoneuston, lasted from the very early morning till mid-morning. The second maximum occurred in the afternoon. The chlorophyll a concentration, and ATP and neuston abundance declined markedly around noon, when the biologically-damaging radiation dose increased, compelling the downward migration of organisms. At the same time, the photo-oxidation of dissolved organic matter intensified and the concentrations of inorganic forms of nitrogen and phosphorus rose. A shift (up to 2 h) between the maximum and minimum neuston concentration in these sea surface layers was indicative of phototaxis occurring within the entire surface microlayer and in the underwater layer. After sunset the decline in phytoneuston abundance could be related to zooplankton grazing as well as to respiratory breakdown.
EN
The similarities and differences in chemical composition of particular sub-layers of the sea microlayer are discussed on the basis of data obtained from the open sea region of the Gdansk Basin. Three methods of microlayer sampling were tested simultaneously, resulting in sub-samples of different mean thickness (10, 90, 250 žm). Samples were analysed to determine dissolved NO3-, NH4+, PO43-, Ptot and DOC, as well as suspended components (chl a, phae a, ATP, POC, particle size distribution and algae). It was found that the stratified microlayer forms a medium extremely diversified chemically and biologically. Variable ranges of concentration as well as varying frequencies of the depletion or enrichment coefficient in each measurement period indicate disparate conditions in the microlayers, which are related to the intensity of primary production and the destruction of organic matter. Comparative studies provided no evidence for the preferential application of any of the sampling techniques to obtain the most accurate picture of dissolved organic and inorganic substances in the sea surface microlayer. In the case of particulate organic matter, satisfactory results were obtained with the classic screen technique. The article highlights the merit of simultaneous studies by various sampling techniques in answering questions related to the sea surface microstructure and the momentum of photochemical and biological processes at its different levels
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