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1

Manganese fractions in water of the polyhumic Siemianowka Dam Reservoir

100%

Cudowski A., Gorniak A.

Polish Journal of Environmental Studies

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2008

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tom 17

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nr 5

713-719

Hydrochemical studies were performed from May to December 2004 at four stations in the polymictic, polyhumic Siemianówka Dam Reservoir (SDR) located on the upper Narew River in northeastern Poland. The total manganese (TMn) concentrations in the reservoir waters varied from 118 μg/dm3 to 638 μg/dm3 , and their increased values are caused by forming complexes with organic matter present in waters flowing from wetlands and forests. Until the moment when the maximum manganese concentration occurred in the reservoir, its upper part was characterized by the higher manganese concentration than the lower part. A long retention time of water delays the occurrence of total manganese maximum in the lower part in SDR. Maximal TMn concentrations were noted in the lower part of the reservoir in the end of summer, while minimal for the upper part in winter. The organic dissolved manganese fractions (ODMn), were the largest part of TMn, slightly less was the particular manganese (PMn) fraction, and the smallest part constituted the reactive dissolved manganese fraction (RDMn). Low concentrations of reactive manganese in winter are due to a low pH value and low concentrations of dissolved organic matter (DOC). Manganese sorption on colloids increases in summer and is accompanied by a pH increase during an intensive photosynthesis of algae and cyanoprocaryota.

2

Quality of the dissolved organic matter [DOM] in the water of Lake Wigry [spectrophotometric analysis]

100%

Dunalska J., Zdanowski B.

Polish Journal of Natural Sciences

|

2004

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tom 16

214-221

3

Empirical formulae for efficiency of DOM removal by adsorption determined on the basis of bench-scale results

100%

Szlachta M., Adamski W.

Polish Journal of Environmental Studies

|

2009

|

tom 18

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nr 3

481-486

4

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Changes in DOC, DON content and DOC/DON ratio of acidic arenosol during two growing periods in pot experiments

100%

Filep T.

Annales Universitatis Mariae Curie-Skłodowska. Sectio E. Agricultura

|

2004

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tom 59

|

nr 4

5

Use of HPLC, Py-GCMS, FTIR methods in the studies of the composition of soil dissolved organic matter

84%

Rosa E., Debska B., Banach-Szott M., Tobiasova E.

Polish Journal of Soil Science

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2015

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tom 48

|

nr 1

The study has determined the composition of dissolved organic matter in Luvisols, Fluvisols and Histosols using spectroscopic (FTIR) and chromatographic (HPLC and Py-GCMS) methods. It has been found that aliphatic hydrocarbons (linear) containing from 4 to 12 atoms of carbon constitute the dominant group of compounds included in the dissolved organic matter (DOC). The preparations isolated from Histosols and Luvisols demonstrated a higher proportion of hydrophobic fraction with a longer retention time probably containing more compounds with long-chain aliphatic and simple aromatic structure than the DOC of Fluvisols. The differences in infrared spectra are evident particularly in the wave number between 1650–1030 cm⁻¹. The DOC of Histosols is richer in aromatic compounds (range 1620 cm⁻¹) but the DOC of Luvisols and Fluvisols is richer in alkene chains and hydroxyl (OH) and methoxy (OCH₃) groups. The results showed differences in the composition of the DOM across the soils, caused their genesis.

6

Variability of fluorescence of dissolved and suspended substances of biological origin in the Gdansk Basin during the International Ecological Experiment “Sopot 87”

84%

Karabashev G. S., Khanaev S. A., Petrosov A. Y.

Oceanologia

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1990

|

tom 28

7

The impact of UV mediated hydrogen peroxide on culturable bacteria in the surface microlayer of eutrophic lake

84%

Walczak M., Swiontek Brzezinska M.

Polish Journal of Ecology

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2009

|

tom 57

|

nr 3

547-554

Hydrogen peroxide (H₂O₂) formation in surface waters is initiated by the absorption of sunlight by dissolved organic matter (DOM). The fraction of the DOM pool that interacts with sunlight, referred to as chromophoric dissolved organic matter, impacts the optical properties of surface waters. Second source of H₂O₂ is wet and dry deposition of photogenerated substance in the atmosphere and biological production. The study examined the concentration of hydrogen peroxide in water from the surface microlayer (SM) (<100 m) and subsurface water (SSW) (25 cm) in the typical eutrophic (TOC 5–15 mg dm⁻³; chlorophyll 5–26 g dm⁻³, water transparency 0.6–1.0 m) lake as well as the impact of this compound on occurrence and survivorship of catalase-positive and catalase-negative bacteria isolated and cultured on the TSA medium (Difco). The experimental H₂O₂ concentrations ranged between 500–5000 nM. The concentration of H₂O₂ in analyzed water samples clearly increased in day-time hours and was different in May, July and October. The highest natural concentration of H₂O₂ (700 nM) was observed in SM water in summer in afternoon hours. During that period, 100% of bacterial populations found in SM water produced catalase. The experiments confirmed that environmental concentrations of H₂O₂ caused no considerable decrease in survivorship of culturable bacteria, while concentrations exceeding 1000 nM were lethal for the majority of catalasenegative bacteria, but not for catalase-positive bacteria.

8

Factors regulating the compositions and distributions of dissolved organic matter in the estuaries of Jiaozhou Bay in North China

84%

Hu J., Zou L., Wang J., Ren Q., Xia B., Yu G.

Oceanologia

|

2020

|

tom 62

|

nr 1

9

Optical classifications of the seas in relation to phytoplankton characteristics

84%

Wozniak B., Pelevin V. N.

Oceanologia

|

1991

|

tom 31

10

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

|

tom 52

|

nr 3

431-471

11

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

The impact of acidic organic matter on the diversity of underwater vegetation in soft water lakes

84%

Bociag K.

Acta Societatis Botanicorum Poloniae

|

2003

|

tom 72

|

nr 3

This paper addresses underwater vegetation in soft water lakes which are influenced by the anthropogenic input of allochtonic dissolved organic matter (DOM) from drained bogs. The aim of this work is to test the hypothesis regarding the role of DOM in shaping the diversity of underwater vegetation. Large differences in underwater vegetation habitats, the limitation of their occurrence to increasingly shallower littoral (the depth of the lower limit of their occurrence decreased from 12 m up to 1 m) and the regression of underwater vegetation were observed in lake types ranging from oligohumic (median (Me) of DOC in water = 2.5 mg C dm-3) to polyhumic (Me of DOC = 35.6 mg C dm-3). The gradual simplification of internal plant patch structure occurred and the Shannon-Weaver diversity index decreased (Me 0.04 → 0.00). Fewer species were observed in the lakes (Me 9 → 2), and the underwater vegetation covered increasingly smaller areas. Species replacement did not occur and no invasive species appeared.

13

Decomposition and utilization of particulate organic matter by bacteria in lakes of different trophic status

84%

Siuda W., Chrost R. J.

Polish Journal of Environmental Studies

|

2002

|

tom 11

|

nr 1

Enzymatic decomposition and bacterial utilization of various types of particulate and dissolved substrates was studied during spring-summer period in four lakes of Mazurian Lake District (Northern Poland). We found that seston particles, similarly as dissolved organic matter (DOM), undergo intensive decomposition processes in lake water, but only after their previous colonization by bacteria. In lakes of low or moderate trophic status free-living microorganisms predominated. They preferentially utilized low molecular weight, dissolved organic compounds. Increases in particulate organic matter (POM) content in these environments caused rapid change of substrate exploitation strategy and adaptation of these bacteria to live in particle-attached forms. In lakes of POM and colloidal DOM (CDOM) abundant particle-attached microheterotrophs, although less metabolically active than free-living bacteria, were mainly responsible for secondary production and POM mineralization A mechanisms that permit effective POM exploitation by seston-attached bacteria was overproduction of relatively low active (high Km) enzymes (e.g. aminopeptidase) and/or synthesis of the enzymes (e.g. β-glucosidase or glucosaminidase) that were optimally adapted (low Km) to the environment.

14

The significance of dissolved organic matter photodegradation as a source of ammonium in natural waters

84%

Grzybowski W.

Oceanologia

|

2002

|

tom 44

|

nr 3

Samples of sea, river and pond water of different absorbance were exposed to artificial radiation resembling sunlight in the UV range. A statistically significant increase in ammonium concentration was detected in pond water of the highest absorbance after 5 h of irradiation. In sea and river water a corresponding increase (< 0.5 μM) was recorded after an exposure time of 25 hours. The bulk characteristics of the analysed samples were insufficient to explain the observed differences.

15

Sunlight-induced changes of biodegradability and absorbance of organic matter dissolved in the Gulf of Gdansk water

84%

Grzybowski W.

Polskie Archiwum Hydrobiologii

|

1999

|

tom 46

|

nr 2

16

Bacterial community structure influenced by Coscinodiscus sp. in the Vistula river plume

67%

Ameryk A., Hahnke R. L., Gromisz S., Kownacka J., Zalewski M., Szymanek L., Calkiewicz J., Dunalska J., Harder J.

Oceanologia

|

2014

|

tom 56

|

nr 4

17

Enzymatic "fingerprinting" of physiological diversity of microbial communities in clear-water and humic lakes

67%

Siuda W., Jasser I., Kiersztyn B.

Polish Journal of Ecology

|

2013

|

tom 61

|

nr 4

Extracellular enzymes occurring in aquatic environment are heterogeneous in respect to their origin and function, place, where they are located and their activity. They can be divided into mainly ‘bacterial-origin’ enzymes produced by heterotrophic organisms in order to obtain organic carbon, and mostly ‘phytoplankton-bacterial-origin’ enzymes, which are produced by autotrophic and heterotrophic organisms, and are responsible mainly for obtaining inorganic compounds. Enzymes activity provides information about microorganisms present in given environment and about their physiological state. We hypothesize that the patterns (‘fingerprints’) calculated on the basis of activity of several enzymes both mainly ‘bacterial-origin’ and mainly ‘phytoplankton-bacterial-origin’ may be used to characterise lake ecosystems in terms of the physiological structure of aquatic microorganisms present in these lakes. For the study we selected four lakes from Mazurian Lakes District in north-eastern Poland. Three of them were clear-water (lakes: Kuc, Mikołajskie, Tałtowisko) and ranged from oligotrophy to eutrophy, the fourth (Lake Smolak Duży) was slightly acidic (pH 5.2), highly productive and polyhumic. Activity of phosphatase (PA), L-leucine-aminopeptidase (AMP), β-glucosidase (B-Glu), esterase (EST), glucosaminidase (Glu-ami), glucuronidase (Glu-uro) and cellobiohydrolase (Cellob) were measured fluorometrically. The results were normalised and analysis of agglomerative clustering was performed to create an enzyme activity patterns characteristic for lakes. We found out that the enzymatic pattern reflected trophic differences between studied lakes. The patterns (‘fingerprints’) of enzymes were similar for three clear-water lakes, with urease (U–ase), AMP and EST dominating the overall enzymatic activity, but differed substantially for polyhumic lake, in which considerably high PA and saccharolytic enzyme activities were observed. We conclude that the analysis of enzymatic ‘fingerprints’ can be a useful tool to characterise lakes with respect to their trophic status and physiological diversity of microbial assemblages associated with each particular lake.

18

Bacterial utilization of carbohydrates in the surface seawater layers of the Gdansk Deep

67%

Mudryk Z., Skorczewski P.

Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline

|

1997

|

tom 01

19

Studies concerning heterotrophic bacteria decomposing macromolecular compounds at two marine beaches

67%

Mudryk Z., Skorczewski P., Perlinski P., Wielgat M.

Oceanological and Hydrobiological Studies

|

2011

|

tom 40

|

nr 3

20

Bacterial utilization of amino acids and carbohydrates in a marine beach

67%

Mudryk Z. J., Podgorska B., Dwulit M.

Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline

|

2005

|

tom 09

Utilization of various amino acids and carbohydrates by heterotrophic bacteria isolated from a sandy beach in Sopot, Poland, southern Baltic Sea coast, was determined. The most intensive growth of bacteria was observed in the presence of amino acids, while carbohydrates were utilized less actively. Differences in the utilization of individual amino acids and carbohydrates by bacteria have been determined. The highest capability to assimilate amino acids and carbohydrates was observed in bacterial strains isolated from the middle part of the studied beach. No major differences were determined in the intensity of assimilation of the tested compounds by bacteria isolated from the surface and subsurface sand layers. Bacterial utilization of amino acids and carbohydrates depended on the chemical structure of those compounds.

Ograniczanie wyników

Manganese fractions in water of the polyhumic Siemianowka Dam Reservoir

Quality of the dissolved organic matter [DOM] in the water of Lake Wigry [spectrophotometric analysis]

Empirical formulae for efficiency of DOM removal by adsorption determined on the basis of bench-scale results

Changes in DOC, DON content and DOC/DON ratio of acidic arenosol during two growing periods in pot experiments

Use of HPLC, Py-GCMS, FTIR methods in the studies of the composition of soil dissolved organic matter

Variability of fluorescence of dissolved and suspended substances of biological origin in the Gdansk Basin during the International Ecological Experiment “Sopot 87”

The impact of UV mediated hydrogen peroxide on culturable bacteria in the surface microlayer of eutrophic lake

Factors regulating the compositions and distributions of dissolved organic matter in the estuaries of Jiaozhou Bay in North China

Optical classifications of the seas in relation to phytoplankton characteristics

Fluorescence measured in situ as a proxy of CDOM absorption and DOC concentration in the Baltic Sea

Role of Nanoplanktons in Marine food-webs

The impact of acidic organic matter on the diversity of underwater vegetation in soft water lakes

Decomposition and utilization of particulate organic matter by bacteria in lakes of different trophic status

The significance of dissolved organic matter photodegradation as a source of ammonium in natural waters

Sunlight-induced changes of biodegradability and absorbance of organic matter dissolved in the Gulf of Gdansk water

Bacterial community structure influenced by Coscinodiscus sp. in the Vistula river plume

Enzymatic "fingerprinting" of physiological diversity of microbial communities in clear-water and humic lakes

Bacterial utilization of carbohydrates in the surface seawater layers of the Gdansk Deep

Studies concerning heterotrophic bacteria decomposing macromolecular compounds at two marine beaches

Bacterial utilization of amino acids and carbohydrates in a marine beach