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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Comparison of in situ and satellite ocean color determinations of particulate organic carbon concentration in the global ocean

100%
Swirgon M., Stramska M.
Oceanologia
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2015
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tom 57
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nr 1
2

Seasonal distribution of dissolved and particulate organic carbon in the water column of a meromictic lake

100%
Dunalska J., Gorniak D., Teodorowicz M., Gasecka K.
Polish Journal of Environmental Studies
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2004
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tom 13
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nr 4
This study investigated concentration changes of dissolved and particulate organic carbon in a meromictic lake to determine the lake’s productivity. It was revealed that the dominant form of organic carbon was the dissolved form (DOC). Maximum production activity was observed in summer (with the peak in June). At the same time, the factors restricting that process were determined, such as: strong pressure of the bacteria competing with the phytoplankton for mineral nutrients, and simultaneous precipitation of phosphates on HS-Fe complexes. The generated organic matter was settling intensively, and one of the transport methods of the dissolved organic matter was adsorption on calcium carbonate and bacterial transformation of the part of DOC into POC.
3

The contents and variability of TOC, POC and DOC concentration in natural waters

100%
Baralkiewicz D., Siepak J.
Polish Journal of Environmental Studies
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1994
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tom 03
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nr 2
This paper reports the results of studies of organic carbon concentrations (TOC, DOC and POC) in samples of natural water. The material studied came from 11 lakes in Wielkopolski National Park, from the Vistula and Warta rivers, 20 public wells situated in rural areas of the Wielkopolska region, and mineral water intakes located at different depths. In the case of surface waters, changes in DOC and POC were recorded for one year. The results were compared with data on natural waters available in literature.
4
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Importance of bacteria and protozooplankton for faecal pellet degradation

84%
Morata N., Seuthe L.
Oceanologia
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2014
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tom 56
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nr 3
5
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Simple statistical formulas for estimating biogeochemical properties of suspended particulate matter in the Southern Baltic Sea potentially useful for optical remote sensing applications

84%
Wozniak S. B.
Oceanologia
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2014
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tom 56
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nr 1
6
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Seasonal changes in particulate organic matter (POM) concentrations and properties measured from deep areas of the Baltic Sea

84%
Winogradow A., Mackiewicz A., Pempkowiak J.
Oceanologia
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2019
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tom 61
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nr 4
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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DOC and POC in the Southern Baltic Sea. Part II — Evaluation of factors affecting organic matter concentrations using multivariate statistical methods

84%
Maciejewska A., Pempkowiak J.
Oceanologia
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2015
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tom 57
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nr 2
8
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Stratification of particulate organic carbon and nitrogen in the Gdańsk Deep (Southern Baltic Sea)

84%
Burska D., Pryputniewicz D., Falkowska L.
Oceanologia
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2005
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tom 47
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nr 2
Particulate organic carbon (POC) and nitrogen (PON) concentrations and fluxes were measured during an experiment in the Gdańsk Deep in late spring (30.05. –06.06.2001). The vertical POC and PON concentration profiles were characterised by the highest values in the euphotic layer,a gradual decrease with depth, and an increase below the halocline. The hydrophysical conditions had a decisive impact on POC and PON fluxes in the water column. Preferential removal of nitrogen from suspended mater was observed in the entire water column (maximum – in the vicinity of thermocline). There were also differences in the diurnal effectiveness of nitrogen removal as compared to carbon removal. The removal rate was highest at night.
9

Variability of organic carbon in water and sediments of the Odra River and its tributaries

84%
Niemirycz E., Gozdek J., Koszka-Maron D.
Polish Journal of Environmental Studies
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2006
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tom 15
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nr 4
This paper presents the results of tests for total organic carbon (TOC) and dissolved organic carbon (DOC) in water and sediments of the Odra River and its tributaries, collected in 1998-2000. TOC and DOC concentrations in tested samples were determined using the multi N-C analyser made by Analytik Jena/In­strument Development Company (IDC). More than 40% of waters from the Odra River and its tributaries were characterized by increased organic substances concentration levels according to Polish and German regulations (10-20 mgC dm-3). TOC and DOC concentrations in water samples were in the range of 3.7­29.0 mgC dm-3 and 2.5-16.3 mgC dm-3, respectively, whereas TOC content in sediments varied between 1.4-176.0 mgC g-1 d.m. Particulate organic carbon (POC) constituted about 20% of TOC in the tributaries and 37% in close-to-mouth water of the Odra River. Based on the obtained results, the temperature influ­ence on the content of organic carbon in water samples was observed. The maximum TOC values were characteristic for spring-summer period, while the minimum ones for the autumn.
10
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Diurnal and seasonal DOC and POC variability in the land-locked sea

67%
Szymczycha B., Winogradow A., Kulinski K., Koziorowska K., Pempkowiak J.
Oceanologia
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2017
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tom 59
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nr 3
Organic matter is a minor yet important component of the marine environment. The aim of this study was to investigate the diurnal and seasonal changes in dissolved and particulate organic carbon (DOC and POC, respectively). Thus, DOC and POC as well as chlorophyll a (Chl a), δ13C, NO3−, NO2−, NH4+, PO43−, salinity, pH, and temperature were regularly measured in samples collected for 24 h (2-h resolution) in the Gdańsk Deep (54°44.730′N, 19°08.531′E) at three water depths (1, 10, and 40 m) during sampling campaigns in 2011 (May), 2014 (May), and 2015 (January, March, May, July, September, November). Seasonal variations in DOC and POC followed the seasonality of Chl a (proportional trend) and nutrients (reverse trend) concentrations. Diurnal oscillations were detected in six out of the eight measurement series. The strongest diurnal variability in both POC and DOC occurred in May 2011 and March 2015, when phytoplankton activity was highest (high Chl a). The surprisingly low δ13C values (range: −28‰ to −24‰) measured over the course of the study revealed the gaps in our knowledge of the isotopic characteristics of terrestrial- vs. marine-derived particulate organic matter.
11
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Numerical modelling of POC dynamics in the Southern Baltic under possible future conditions determined by nutrients, light and temperature

67%
Dzierzbicka-Glowacka L., Kulinski K., Maciejewska A., Jakacki J., Pempkowiak J.
Oceanologia
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2011
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tom 53
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nr 4
This paper discusses predictions of particulate organic carbon (POC) concentra- tions in the southern Baltic Sea. The study is based on the one-dimensional Particulate Organic Carbon Model (1D POC), described in detail by Dzierzbicka- Głowacka et al. (2010a). The POC concentration is determined as the sum of phytoplankton, zoo- plankton and dead organic matter (detritus) concentrations. Temporal changes in the phytoplankton biomass are caused by primary production, mortality, grazing by zooplankton and sinking. The zooplankton biomass is affected by ingestion, excretion, faecal production, mortality and carnivorous grazing. The changes in the pelagic detritus concentration are determined by the input of dead phytoplankton and zooplankton, the natural mortality of predators, faecal pellets, and sinks – sedimentation, zooplankton grazing and biochemical decomposition. The model simulations were done for selected locations in the southern Baltic Sea (Gdańsk Deep, Bornholm Deep and Gotland Deep) under predicted conditions characterized by changes of temperature, nutrient concentrations and light availability. The results cover the daily, monthly, seasonal and annual POC concentration patterns in the upper water layer. If the assumed trends in light, nutrients and temperature in the southern Baltic correctly predict the conditions in 2050, our calculations indicate that we can expect a two- to three-fold increase in POC concentration in late spring and a shift towards postponed maximum POC concentration. It can also be anticipated that, as a result of the increase in POC, oxygenation of the water layer beneath the halocline will decrease, while the supply of food to organisms at higher trophic levels will increase.
12
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Content available

DOC and POC in the water column of the Southern Baltic. Part I. Evaluation of factors influencing sources, distribution and concentration dynamics of organic matter

67%
Maciejewska A., Pempkowiak J.
Oceanologia
|
2014
|
tom 56
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nr 3
13
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Inherent optical properties of suspended particulate matter in the Southern Baltic Sea

67%
Wozniak S. B., Meller J., Lednicka B., Zdun A., Ston-Egiert J.
Oceanologia
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2011
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tom 53
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nr 3
The inherent optical properties (IOPs) of suspended particulate matter and their relations with the main biogeochemical characteristics of particles have been examined in the surface waters of the southern Baltic Sea. The empirical data were gathered at over 300 stations in open Baltic Sea waters as well as in the coastal waters of the Gulf of Gdańsk. The measurements included IOPs such as the absorption coefficient of particles, absorption coefficient of phytoplankton, scattering and backscattering coefficients of particles, as well as biogeochemical characteristics of suspended matter such as concentrations of suspended particulate matter (SPM), particulate organic matter (POM), particulate organic carbon (POC) and chlorophyll a (Chl a). Our data documented the very extensive variability in the study area of particle concentration measures and IOPs (up to two orders of magnitude). Although most of the particle populations encoun- tered were composed primarily of organic matter (av. POM/SPM=ca 0.8), the different particle concentration ratios suggest that the particle composition varied significantly. The relations between the optical properties and biogeochemical parameters of suspended matter were examined. We found significant variability in the constituent-specific IOPs (coefficients of variation (CVs) of at least 30% to 40%, usually more than 50%). Simple best-fit relations between any given IOP versus any constituent concentration parameter also highlighted the significant statistical errors involved. As a result, we conclude that for southern Baltic samples an easy yet precise quantification of particle IOPs in terms of the concentration of only one of the following parameters – SPM, POM, POC or Chl a – is not achievable. Nevertheless, we present a set of best statistical formulas for a rough estimate of certain seawater constituent concentrations based on relatively easily measurable values of seawater IOPs. These equations can be implemented in practice, but their application will inevitably entail effective statistical errors of estimation of the order of 50% or more.
14
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Content available

Particulate organic carbon in the Southern Baltic Sea: numerical simulations and experimental data

67%
Dzierzbicka-Glowacka L., Kulinski K., Maciejewska A., Jakacki J., Pempkowiak J.
Oceanologia
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2010
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tom 52
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nr 4
Particulate Organic Carbon (POC) is an important component in the carbon cycle of land-locked seas. In this paper, we assess the POC concentration in the Gdańsk Deep, southern Baltic Sea. Our study is based on both a 1D POC Model and current POC concentration measurements. The aim is twofold: (i) validation of simulated concentrations with actual measurements, and (ii) a qualitative assessment of the sources contributing to the POC pool. The POC model consists of six coupled equations: five diffusion-type equations for phytoplankton, zooplankton, pelagic detritus and nutrients (phosphate and total inorganic nitrogen) and one ordinary differential equation for detritus at the bottom. The POC concentration is determined as the sum of phytoplankton, zoo-plankton and pelagic detritus concentrations, all expressed in carbon equivalents. Bacteria are not simulated in this paper. The observed large fluctuations of POC concentrations are attributed to its appreciable seasonal variability. The maximum concentration of POC varied between 870 mgC m−3 in May and 580 mgC m−3 in September, coinciding with the period of maximum dead organic matter and phytoplankton biomass concentrations. The results of the numerical simulations are in good agreement with observed values. The difference between the modelled and observed POC concentrations is equal to 3–28% and depends on the month for which the calculations were made, although no time trend of the difference is observed. The conclusion is that the numerical simulations are a ufficiently good reflection of POC dynamics in the Baltic.
15
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Content available

Diffusive component of the vertical flux of particulate organic carbon in the North polar Atlantic

67%
Stramska M.
Oceanologia
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2006
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tom 48
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nr 4
The diffusive component of the vertical flux of particulate organic carbon (POC) from the surface ocean layer has been estimated using a combination of the mixed layer model and ocean color data from the SeaWiFS satellite. The calculations were carried out for an example location in the north polar Atlantic centered at 75◦N and 0◦ E for the time period of 1998–2004. The satellite estimates of surface POC derived using a regional ocean color algorithm were applied as an input to the model driven by local surface heat and momentum fluxes. For each year of the examined period, the diffusive POC flux was estimated at 200-m depth from April through December. The highest flux is generally observed in the late fall as a result of increased heat loss and convectional mixing of surface waters. A relatively high diffusive POC flux is also observed in early spring, when surface waters are weakly stratified. In addition, the model results demonstrate significant interannual variability. The highest diffusive POC flux occurred in 1999 (about 4500 mg m−2 over the 9-month period). In 1998 and 2002 the estimated flux was about two orders of magnitude lower. The interannual variability of the diffusive POC flux is associated with mixed layer dynamics and underscores the importance of atmospheric forcing for POC export from the surface layer to the ocean’s interior.
16

Transfer of organic matter in a lake included in the power plant cooling system [Wielkopolsko-Kujawskie Lake District, Poland]

59%
Dunalska J., Zdanowski B., Stawecki K., Marchlik W.
Electronic Journal of Polish Agricultural Universities. Series Environmental Development
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2005
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tom 08
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nr 1
For assessment of the organic matter mobility rate, dissolved and particulate organic carbon were used. Quality of the organic matter was determined on the grounds of the relative indicator of aromatic properties (SUVA260) and the absorbance ratio at 260 nm (A260) and 330 nm (A330). The study has revealed that the dominant form of organic carbon is the dissolved form (DOC). The main source of organic matter is the autochthonous production, intensifying in spring, which is exhibited by the growth of the heterotrophic bacteria number and intensive phytoplankton bloom. Organic matter in the lake is transferred both spatially and vertically. The rate of these processes is determined by, respectively: forced water flow resulting from the cooling waters dump and sedimentation of organic matter on organic and inorganic suspensions, which is favoured by the carbonate-calcareous character of the Lake Mikorzyńskie waters. Organic matter adsorption to calcium carbonate and destruction running with the heterotrophic bacteria participation are one of the major factors limiting the heavy degradation of the lake waters.
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