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  1. 9 Oceanologia

  2. 9 Polish Journal of Environmental Studies

  3. 5 Polish Journal of Ecology

  4. 2 Oceanological and Hydrobiological Studies

  5. 1 Acta Agrophysica

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  1. 4 Pempkowiak J.

  2. 4 Zielinski P.

  3. 3 Gorniak A.

  4. 3 Kulinski K.

  5. 3 Maciejewska A.

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  1. 1 2021

  2. 2 2017

  3. 3 2015

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1
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Content available

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

The role of mid-field ponds in the storage of dissolved organic compounds [DOC] and heavy metals

100%
Zyczynska-Baloniak I., Jaskulska R., Szteke B.
Polish Journal of Environmental Studies
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1996
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tom 05
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nr 4
This paper presents a study on the concentration of dissolved organic carbon (DOC) and humic substances (HS) in the waters of two different small ponds located in agricultural environments. DOC and HS content is high in the water of pond R adjacent to cultivated fields (DOC 42.0 mg/1, HS 34.2 mg/1) and in pond H surrounded by a wide belt of meadow and settled by macrophytes (DOC 48.0 mg/1, HS 37.2 mg/1). The total amounts of cations and cations bounded with humic substances dissolved in water of these two ponds have been analyzed. These studies indicate that small field ponds are a good biogeochemical barrier controlling organic compound migration with water from arable fields into water reservoirs.
3

The content of DOC, POC, and TOC in lobelian lakes

100%
Baralkiewicz D., Kraska M., Siepak J.
Polish Journal of Environmental Studies
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1996
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tom 05
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nr 6
The material for our study came from 44 lobelian lakes located near Bytów. The lakes differed in size, depth, and drainage area development. The objective of the study was to determine the content of TOC, DOC, and POC in these lakes using a high temperature method. COD was also measured using a dichromate method, and after that the results were expressed by the TOC values. Then the TOC values obtained via the two methods were compared. The lakes under investigation proved to contain different amounts of dissolved organic carbon (1.8-19.0 mg/1), with POC falling within the range 0-33% of TOC.
4

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.
5
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The effect of dissolved organic carbon on pelagial and near-sediment water traits in lakes

100%
Banas K.
Acta Societatis Botanicorum Poloniae
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2005
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tom 74
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nr 2
The effect of dissolved organic carbon (DOC) on the environmental conditions of macrophytes has been studied in 35 lakes divided into soft- and hardwater: oligohumic (<4.0 mg C dm-3), α-mesohumic (4.0-8.0 mg C dm-3), β-mesohumic (8.1-16.0 mg C dm-3) and polihumic (>16.0 mg C dm-3). The optimum environmental conditions for macrophytes have been found in oligohumic lakes, characterised by low water colour and its good transparency. In soft- and hardwater lakes increasing concentration of DOC is accompanied with an increase in the colour (r=0.95), while the visibility decreases. With increasing DOC in the near-sediment layer the pH values decrease while the concentration of nitrogen increases and the concentration of phosphorus slightly increases. In hardwater lakes with increasing DOC concentration, the redox potential, conductivity, total hardness and calcium concentration in the near-sediment water decrease, whereas the content of CO2 remains at a very low level.
6

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.
7

Survival of Ceriodaphnia dubia [Crustacea, Cladocera] exposed to different screens against natural ultraviolet radiation

84%
De L. R. P., Acevedo P., Verdugo K.
Polish Journal of Environmental Studies
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2007
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tom 16
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nr 3
481-485
The current increase of penetration of natural ultraviolet radiation (UVR ) in southern South America affects water bodies because the UVR can penetrate the water column. In this scenario, the zooplankton develops photoprotective strategies such as vertical migrations against UVR or synthesis of photoprotective substances. The present study was done using a population of Ceriodaphnia dubia. that was collected from small shallow wetland near Temuco, Chile. The specimens were exposed for 7 to 9 hours to natural ultraviolet radiation, and with different colored nylon as protection against UVR , the experiment was done during the southern summer of 2006. The results revealed that in the presence of protection against UVR provided by colored nylon, the mortality was low, whereas under exposure to UVR and covering by transparent nylon total mortality was observed. The relation between mortality and the dose of UV that can penetrate the different colored nylon is represented by LC₅₀ in UV (280-400 nm) and UVB (280-320 nm), within intensities of 234.82 and 14.96 kJ/m², respectively.
8
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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
|
tom 57
|
nr 2
9
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Could submarine groundwater discharge be a significant carbon source to the Southern Baltic Sea?

84%
Szymczycha B., Maciejewska A., Winogradow A., Pempkowiak J.
Oceanologia
|
2014
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tom 56
|
nr 2
10
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Fluorescence measured in situ as a proxy of CDOM absorption and DOC concentration in the Baltic Sea

84%
Kowalczuk P., Zablocka M., Sagan S., Kulinski K.
Oceanologia
|
2010
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tom 52
|
nr 3
431-471
11
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Role of Nanoplanktons in Marine food-webs

84%
Das N., Pandey A.
International Letters of Natural Sciences
|
2015
|
tom 43
Nanoplanktons are ubiquitous protozoan zooplankton in a size range of 2 to 20 μm, play key ecological roles in aquatic ecosystems. Heterotrophic nanoflagellates are distributed through the continental shelf and margin area of the oceans as well as deep-sea. These organisms contribute significantly to the total living biomass within these systems, serve as the major top–down control on bacterial assemblages, and are an important source of mortality for microalgae and other heterotrophic nanoflagellates. From many recent studies, it is generally accepted that HNF is one of the most important bacterial consumers. They also function as important remineralizers of organic matter and nutrients in aquatic systems. In accordance with these important ecological roles, heterotrophic nanoflagellates have been the subject of considerable study both in the field and laboratory.
12

Preliminary results of dissolved organic carbon concentration measurements in the Vistula river mouth using high-temperature catalytic oxidation

84%
Grzybowski W.
Oceanologia
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1996
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tom 38
|
nr 3
13

Changes in water chemistry along the course of two rivers with different hydrological regimes

84%
Zielinski P., Gorniak A., Suchowolec T.
Polish Journal of Environmental Studies
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2003
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tom 12
|
nr 1
Chemical composition of water and dissolved organic carbon (DOC) levels were investigated over three years, along two large rivers in NE Poland, with different hydrological regimes. One river was from lakeland and the second a typical lowland river with forests and high contributions of peatlands in the catchment. The study involved hydrological (specific runoff, river discharge) effects on the variability of water chemistry and DOC concentrations. Specific runoff and discharge influence on DOC level and water quality. DOC concentrations and chemical water parameters were highest in the upper part of the lowland river and lowest in the upper course of the lakeland river. A two times lower DOC concentration was observed in the river draining lakeland with high values of specific runoff than in the lowland river. In typical lowland rivers organic compounds (mainly natural humic substances) intensified water eutrophication along the river course.
14
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Content available

Transformation of nitrogen compounds in the muckous soils of a forest island

84%
Meysner T., Maryganova V., Szajdak L.
Acta Agrophysica
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2006
|
tom 07
|
nr 2[133]
15

Effect of pH, dissolved organic carbon and total phosphorus concentrations on selected life history traits of Luronium natans [L.] Raf.

84%
Bazydlo E., Szmeja J.
Polish Journal of Ecology
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2004
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tom 52
|
nr 2
A hypothesis has been put forward that low pH or high concentration of total phosphorus (TP) and dissolved organic carbon (DOC) in the lake water are the factors responsible for observed extinction of the population of Luronium natans (L.) Raf., protected macrophyte species from the group of isoetids. A study was performed on 525 generative individuals collected from 21 lakes in Pomeranian Lakeland (NW Poland) and a correlation between the biometric characteristics and environmental conditions in the lakes was tested. The following life history traits have been analysed: size of individuals, their fecundity and allocation of biomass. The greatest and most fecund individuals grow in the lake water of pH 6.1–7.0, poor in TP (10.1–20.0 µg dm⁻³) and DOC (3.5–6.0 mg C dm⁻³). The allocation of biomass of the individuals growing in the optimum conditions is as follows 46–54% in the leaves, 22–31% in the roots and 20–27% in the rhizome. In the lakes with water of pH < 5.0 or of TP > 20.1 µg dm⁻³ and DOC > 6 mg C dm³, a statistically significant decrease in the size of the individuals and unfavourable changes in the biomass allocation are found. The main environmental factor responsible for dying out of local populations of Luronium natans is a decrease of pH below < 5.0.
16

Contamination of coastal water samples collected for organic carbon analysis by a surface microlayer

84%
Grzybowski W.
Polish Journal of Ecology
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2001
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tom 49
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nr 2
17

Effects of high water levels on bacterioplankton abundance in the Danube River floodplain [Kopacki Rit, Croatia]

84%
Palijan G., Bogut I., Vidakovic J.
Polish Journal of Environmental Studies
|
2007
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tom 16
|
nr 1
Effects of high water levels on the abundance of colony-forming units of eutrophic and oligotrophic bacteria were investigated. Changes in their proportion were exploited as the biological indicator of organic substrate availability. It was also reconsidered, to a certain extent, which source (autochtonous or allochtonous) of organic substrate and bacteria prevails during floods. Water samples were collected from the surface and from the bottom during high water levels in the floodplain lake (Kopačko Lake) and the connecting channel (Hulovo Channel). The relative abundance of oligotrophs vs. eutrophs was considerably higher at the end of investigation, to which higher abundance of eutrophs preceded at Kopaèko Lake sampling station. Also in Kopačko Lake, a considerably higher abundance of bacteria was noticed in the bottom samples during first intensive flooding pulses. Elevated bacterial abundance was connected with the sufficiently intensive floods (eutrophs dominate) but also with the water properties established following the settling down of disturbed conditions (oligotrophs dominate). Greater abundance in the bottom samples established during the first intensive pulse suggests a sediment origin of bacteria, while considerable differentiation between oligotrophic and eutrophic bacteria suggests an establishment of lower quality of organic substrate at the end of the investigation.
18

Survival of pigmented freshwater zooplankton, exposed to artificial ultraviolet radiation and two levels of dissolved organic carbon

84%
De L. R. P.
Polish Journal of Ecology
|
2005
|
tom 53
|
nr 1
The increase in penetration of ultraviolet radiation has been reported currently over southern South America. It would affect the photoprotective responses in biotic elements of freshwater ecosystems. An experiment was designed using pigmented adult individuals of the species Daphnia dadayana (Paggi 1999), Boeckella antiqua (Menu-Marque & Balseiro 2000), and Parabroteas sarsi (Mrázek 1901), characteristic for shallow fishless ponds from South American plains (located between 41 and 53°S latitude). The artificial ultraviolet radiation was involved in the experiment, with two levels of dissolved organic carbon (DOC), which would exert a protective effect against ultraviolet radiation. The results of this experiment showed that under conditions of low DOC concentrations, D. dadayana recorded a higher mortality, while under low DOC concentrations, B. antiqua and P. sarsi were not affected by ultraviolet radiation. Daphnids would be less tolerant to the exposure to ultraviolet radiation than pigmented calanoid copepods.
19

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
|
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.
20
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Benthic diffusive fluxes of organic and inorganic carbon, ammonium and phosphates from deep water sediments of the Baltic Sea

67%
Lengier M., Szymczycha B., Brodecka-Goluch A., Klostowska Z., Kulinski K.
Oceanologia
|
2021
|
tom 63
|
nr 3
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