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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Mercury fluxes through the sediment water interface and bioavailability of mercury in Southern Baltic Sea sediments

100%
Beldowski J., Miotk M., Pempkowiak J.
Oceanologia
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2009
|
tom 51
|
nr 2
263-285
Sediment cores collected in several areas of the southern Baltic were analysed for total mercury (HgTOT) and five operationally defined mercury fractions: HgA – contained in pore waters, HgF – bound to fulvic acids, HgH – bound to humic acids, HgS – bound to sulphide, and HgR – residual. An effort was made to quantify mercury fluxes at the sediment/water interface in the study area. Net mercury input, calculated on the basis of sedimentation rate and concentration in the uppermost sediments, ranged from 1 to 5.5 ng cm−2 year−1. Mercury remobilisation from sediments due to diffusion and resuspension was calculated from the proportion of labile mercury and the velocity of near-bottom currents. The results showed that the return soluble and particulate fluxes of mercury from the sediments to the water column constitute a substantial proportion of the input (20–50%), and are slightly higher than those found in pristine areas, although they are less than the values recorded in areas with a history of mercury contamination. In addition, an index was developed to assess the methylation potential of mercury in sediments. Mercury contained in pore waters, and mercury bound to fulvic and humic acids together with Loss on Ignition were used to calculate the semiquantitative methylation potential (Pm). Despite the simplicity of this approach, Pm correlates well with methyl mercury in fish from the study area.
2

Zmiany globalne a zagrożenia dla, i ze strony Morza Bałtyckiego

100%
Pempkowiak J., Beldowski J., Kulinski K.
Studia. Polska Akademia Nauk. Komitet Przestrzennego Zagospodarowania Kraju
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2009
|
tom 124
Global changes and associated threats to, and by the Baltic Sea
3

Broń chemiczna zatopiona w Morzu Bałtyckim

100%
Beldowski J., Sosnowska A., Podscianski A.
Aura
|
2013
|
nr 08
4

Szalony kapelusznik i morze

99%
Beldowski J., beldowska M.
Wiedza i Życie
|
2003
|
nr 11
76-79
5
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Recent alterations of aerosol concentration, mercury distribution and organic matter deposition in the Arctic

88%
Pempkowiak J., Zielinski T., Petelski T., Zaborska A., Beldowski J.
Papers on Global Change
|
2011
|
nr 18
Material fluxes in the Arctic and Antarctic have been, in several respects, strongly affected recently. For example, atmospheric turbidity conditions are frequently subject to strong changes due to haze and dust transport episodes, which can cause considerable perturbations in the radiation balance of the atmosphere beyond regional scale. This, directly or indirectly, contributes to the increased mercury deposition and organic matter fluxes to sediments. The results show that local emissions are not always the most important factors influencing the composition of aerosol in the atmosphere of the west Spitsbergen region. The direct radiative impact of polar aerosols on the surface and at the top of the atmosphere (TOA) need to be studied more closely through both theoretical studies on the aerosol radiative properties and measurements of the surface reflectance characteristics. Mercury dissolved/solid partitioning, both in the unconsolidated, fluffy layer of suspended matter covering the sediments, and the uppermost sediment layer, indicate that the influence of the athmospheric mercury deposition event (AMDE) can prolong well into summer (July/August), and can provide a pathway to the food chain for mercury contained in sediments. Since terrigenous supplies of organic carbon to the Barents Sea are minor (∼5%) compared to the marine supply, modern sediment deposits in this region sequester on average 6.0 g/m2year organic carbon, or 5.8% of the annual integrated pelagic primary production. This burial fraction exceeds, by a factor of 3, the burial fraction derived for the Holocene.
6
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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The contribution of the fine sediment fraction to the Fluffy Layer Suspended Matter (FLSM)

76%
Pempkowiak J., Beldowski J., Pazdro K., Staniszewski A., Leipe T., Emeis K. C.
Oceanologia
|
2002
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tom 44
|
nr 4
Fluffy Layer Suspended Matter (FLSM) is a layer of fairly concentrated suspended matter resting on the sea floor. Its passage to the depositional basins in the Pomeranian Bay – Arkona Deep System of the Baltic Sea is estimated to take around six months. In the course of this migration, the properties of FLSM change as a result of ageing and the influx of fresh particles from the water column, and possibly also because of mass exchange with the uppermost sediment layers. Measurements of radioisotopes (210Po, 210Pb, 137Cs) have demonstrated that in shallow water this topmost layer of sediments, from 8 cm to 3 cm in thickness, is subject to mixing. This creates redox profiles favourable to biota and bioturbation. Basing on 210Pb/210Po disequilibria and the 210Po excess, it was estimated that under steady state conditions from 1.5 to 2.2% of fine fraction (FSF) in the mixed layer of sediments is freshly imported from FLSM. This implies replacement of FSF from the sediments and its incorporation into FLSM. On the assumption that the surface density of FLSM is 10 mg cm−2, FSF freshly exported from sediments actually comprises up to 15% of FLSM. Therefore, the properties of FLSM are strongly influenced by the processes taking place in the sediments, although FLSM by definition is independent of sediments.
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Variations in organic matter bound in fluffy layer suspended matter from the Pomeranian Bay (Baltic Sea)

76%
Pazdro K., Staniszewski A., Beldowski J., Emeis K. C., Leipe T., Pempkowiak J.
Oceanologia
|
2001
|
tom 43
|
nr 4
Fluffy layer suspended matter (FLSM) and surface sediment samples from the Pomeranian Bay were examined for fatty acid, lipid and organic matter contents. FLSM is a several-centimetre-thick layer of fairly concentrated particulate matter lying on the sea floor significantly affecting the flux of matter to depositional basins. Analyses of fatty acids were used to establish sources and decomposition rates of labile organic matter along a transect from the shallow, highly dynamic, Odra estuary to the Arkona Basin, a deep, low energy, depositional area. In FLSM and sediments respectively, the ranges of organic matter contents were 4.0–25.0% and 5.1–23.0%, those of lipids 0.1–5.4% and 0.30–1.67%, and those of fatty acids 50–991 μg g−1 dry wt. and 100–546 μg g−1 dry wt. In shallow waters, the contents of these compounds are very variable, mirroring variations in biological activity and hydrological conditions. The high percentage of polyunsaturated fatty acids in shallow areas indicates the presence of fresh, undegraded, labile organic matter of autochthonous origin. Fatty acids, the most labile components, are transported as suspended matter attached to minerals and finally accumulated in the depositional area in the form of condensed organic macromolecules. The intensity of bacterial decomposition of organic matter in this system is reflected in the high percentage of branched fatty acids. The low fatty acid content in the organic matter is attributed to the high rate of decomposition of the labile organic matter. No linear correlation was found between the contents of fatty acids and lipids.
8
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Temporal and spatial changes of cadmium in the near-bottom suspended matter of the Pomeranian Bay - Arkona Deep system

76%
Staniszewski A., Pazdro K., Beldowski J., Leipe T., Emeis K. C., Pempkowiak J.
Oceanologia
|
2000
|
tom 42
|
nr 4
Owing to the high toxicity of cadmium (Cd) towards biota and the considerable quantities of this element entering the environment from anthropogenic sources, interest in its biogeochemistry is increasing. This is also true for the marine environment, which serves as a sink for both natural and anthropogenic Cd loads entering the hydrosphere and the atmosphere. The distribution of Cd in the coastal zone of the marine environment is governed primarily by the flux of the so-called fluffy layer suspended matter (FLSM), which spreads across the top of the sea floor as a several-centimetre-thick layer containing highly concentrated suspended matter. Both total contents and solid speciation of Cd was measured in FLSM collected in the Pomeranian Bay – Arkona Deep system (Western Baltic Proper) in the course of the three-year-long study. Seasonal changes in the total Cd content (0.5–1.8 μg g−1 dry matter) were attributed to the contribution of organic suspensions originating from algal blooms. The decreasing content of Cd in FLSM offshore is due to the input of Cd-rich suspended matter from the River Odra (Oder), and the decreasing organic matter content in FLSM with increasing depth. The contribution of labile fractions (adsorbed and bound to iron(III) hydroxides) was found to be from 50 to 75% of the total content. In view of the substantial mobility and bioavailability of the fractions, this is a highly alarming feature.
9

Chemia w Baltyku

75%
Beldowska M., Beldowski J.
Wiedza i Życie
|
2005
|
nr 07
42-45
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