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1

Day-to-night activity of bacteria in the surface microlayer eutrophic lake

100%
Walczak M.
Polish Journal of Ecology
|
2008
|
tom 56
|
nr 3
379-389
This study examined changes of bacteria numbers in the surface microlayer (SM) and subsurface water (SW) of a lake during a day- and night-time. The research also addresses the synthesis of DNA and cell protein as well as the activity of cellular dehydrogenases depending on time of the day. Results demonstrated that in spring and summer the numbers of bacteria (per cm3 ) in the SM was significantly greater during night-time than day-time (average: May, daytime – 30.058 × 10⁶, night-time – 71.343 × 10⁶; July, day-time – 10.801 × 10⁶, night-time – 40.353 × 10⁶). In October, numbers of bacteria in dayand night-time were not statistically different (respectively: 5.841 × 10⁶ and 3.664 × 10⁶). Results indicated also that the rate of DNA synthesis by SM bacteria was much higher in the night-time (average: May – 2.049 × 10⁻⁶ pg h⁻¹ cell⁻¹; July – 1.363 × 10⁻⁶ pg h⁻¹ cell⁻¹), than in the day-time (average: May – 0.7263 × 10⁻⁶ pg h⁻¹ cell⁻¹; July – 0.3404 ×10⁻⁶ pg h⁻¹ cell⁻¹). In contrast, in October the values of DNA synthesis by SM bacteria were higher in night-time. These changes are significantly smaller in SW at a depth of several dozen centimetres. However, no significant impact was observed of a time of the day on the activity of protein synthesis and activity of cellular dehydrogenases by bacteria inhabiting SM and SW.
2

Comparison of phytoplankton and autotrophic picoplankton populations from a pond's surface and subsurface waters over 24-hour period

100%
Marshall H. G., Burchardt L., Wilk-Wozniak E.
Oceanological and Hydrobiological Studies
|
2005
|
tom 34
|
nr Suppl.3
3

Air-water interface in an estuarine lake: chlorophyll and nutrient enrichment

84%
Antonowicz J. P.
Polish Journal of Ecology
|
2018
|
tom 66
|
nr 3
The surface water microlayer (SML) is a thin layer found at the interface of the hydrosphere and the atmosphere. It is capable of accumulating chemical substances and microorganisms at a rate as high as 100-fold greater than that observed in the subsurface water. The rate of accumulation of biogens and chlorophyll a in SML of an estuary, where marine and fresh waters mix, varies considerably and it depends on the degree mixing of these waters, which is manifested in the varying values of the enrichment factor (EF, calculated as the ratio of nutrients concentration in SML versus subsurface water). The influence of the Baltic Sea marine water and the freshwater Łeba River inflows on the estuarine Lake Łebsko (Poland) was examined. Nine sampling sites were located in the estuary. Water samples were collected from two layers: the surface microlayer (thickness 242 µm ± 40) and the subsurface water (15 cm depth). The capacity of the SML to enrich the water in nutrients and chlorophyll differed among various parts of the estuary, as well as between seawater and river waters. Statistically significant higher EF were found in the marine waters than in river waters for the nitrogen and phosphorus compounds as well as chlorophyll. There were also differences in EF between marine and lake waters. The highest EF were also recorded for organic forms of nitrogen and phosphorus in marine water. Most probably, marine flux into the estuarine Lake Łebsko, resulted in the increased EF for these investigated components.
4

Prokaryotes from different phylogenetic groups in surface microlayer and subsurface water in a eutrophic lake

84%
Burkowska A., Walczak M.
Polish Journal of Environmental Studies
|
2013
|
tom 22
|
nr 4
Prokaryotes from different phylogenetic groups were studied in surface microlayer (SM, up to 100 μm) and subsurface water (SW – 20 cm) in a eutrophic lake over three months (July, August, and October). The abundance of prokaryotes was determined by epifluorescence microscopy after DAPI staining, and phylogenetic diversity was determined by fluorescence in situ hybridization (FISH) with group-specific, fluorescently labeled oligonucleotide probes. In SW bacteria made up most of the entire community of DAPI-stained microorganisms (54-69%) and in SM bacteria made up only 33-44% of DAPI-stained microorganisms. Archaea corresponded to a small fraction of both bacterioneuston and bacterioplankton. The counts of Archaea and bacteria were significantly higher in SW than in SM. Among all proteobacteria included in the research, γ-proteobacteria represented the most abundant fraction: 42-72% in SM and 39-61% in SW. Statistical analysis revealed that the abundance of γ-proteobacteria is positively correlated with temperature and with dissolved oxygen. β-proteobacteria were the least abundant fraction.
5
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Frequency of antibiotic resistance in bacteria inhabiting water of downtown pond

84%
Mudryk Z., Skorczewski P.
Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline
|
2009
|
tom 13 part I
Antibiotic resistance of heterotrophic bacteria isolated from the surface microlayer and subsurface water of downtown pond was determined. The levels of resistance of bacteria to various antibiotics differed considerably. It follows from the results that bacteria were most resistant to penicillin and sensitive to gentamycin, neomycin and oxytetracycline. Majority of bacterial strains were characterised by resistance to 6-8 of 18 antibiotics tested. As a rule, there were no significant differences in antibiotic resistance between neustonic and planktonic bacteria. Pigmented bacteria were more antibiotic resistant than non-pigmented ones.
6
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The influence of heavy metal ions on neustonic bacteria

84%
Donderski W., Walczak M., Mudryk Z., Skorczewski P.
Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline
|
1999
|
tom 03
7

Nonylphenol and 4-tert-octylphenol in the Gulf of Gdansk coastal zone

84%
Staniszewska M., Falkowska L.
Oceanological and Hydrobiological Studies
|
2011
|
tom 40
|
nr 2
8
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Extracellular enzyme activity in the surface microlayer and subsurface water in the coastal lake Dolgie Wielkie

84%
Zdanowicz M., Mudryk Z. J., Perlinski P.
Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline
|
2018
|
tom 22
The paper presents studies on level hydrolytic activity of extracellular enzymes in the surface microlayer and subsurface water in the coastal lake Dołgie Wielkie. The ranking order of the potential enzyme activity rates in the studied water layers was as follows: aminopeptidase > lipase > α-glucosidase > β-glucosidase. The level of activity of all studied hydrolases was higher in the surface microlayer than subsurface water. Activity of extracellular enzymes was influenced by the season.
9

The effect of mercury [Hg2], copper [Cu2] and zinc [Zn2] ions on bacteria isolated from surface microlayer and subsurface water of the Lake Maly Jeziorak

84%
Donderski W., Gluchowska M., Wodkowska A.
Biological Bulletin of Poznań. Supplement
|
1996
|
tom 33
10

Neustonic bacteria number, biomass and taxonomy

84%
Donderski W., Walczak M., Mudryk Z., Kobylinski M.
Polish Journal of Environmental Studies
|
1999
|
tom 08
|
nr 3
11

Antibiotic resistance among bacteria inhabiting surface and subsurface water layers in estuarine Lake Gardno

84%
Mudryk Z. J.
Polish Journal of Environmental Studies
|
2002
|
tom 11
|
nr 4
Antibiotic resistance of heterotrophic bacteria isolated from the surface and subsurface water of estuarine lake Gardno was determined. The levels of resistance of bacteria to various antibiotics differed considerably. Antibiotic resistance between neustonic and planktonic bacteria and microflora inhabiting different parts of lake Gardno was nearly identical. Besides gentamycin, no differences in the antibiotic resistance between pigmented and non-pigmented bacteria were noted. Majorities of bacterial strains were characterised by resistance to 4-6 antibiotics. Bacterial resistance to antibiotics was dependent on chemical structure.
12

The subsurface water system role for surface and coastal water pollution

67%
Destouni G.
International Journal of Ecohydrology and Hydrobiology
|
2007
|
tom 07
|
nr 2
157-164
13

Aromatic hydrocarbon decomposition by neustonic bacteria. Part I. Single-ring hydrocarbon biodegradation

67%
Walczak M., Donderski W., Mudryk Z., Skorczewski P.
Polish Journal of Environmental Studies
|
2000
|
tom 09
|
nr 6
471-474
The present paper provides an account of a study on benzene, toluene and xylene degradation by neustonic and planktonic bacteria in lake Jeziorak Mary. Aromatic hydrocarbons were better decomposed by neustonic bacteria than planktonic bacteria. Moreover, the obtained data point to the total number of bacteria and heterotrophic bacteria number being greater in surface microlayer than in subsurface water.
14
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Physiological properties of bacteria inhabiting coastal lake surface and subsurface water layers

67%
Skorczewski P., Mudryk Z. J.
Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline
|
2005
|
tom 09
Results of the studies on the occurrence of bacteria displaying particular physiological properties in coastal Lake Gardno are presented. Most numerous groups among neustonic and planktonic bacteria studied were ammonifying and producing hydrogen sulphide from organic compounds strains. Nitrifying bacteria were not numerous among isolated strains. It was demonstrated that significant differences in the abundance of individual physiological groups bacteria existed in water layers, stations and seasons.
15
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Zmienność wskaźnika zagrożenia suszą w pokrywach glebowo-zwietrzelinowych pogórskiego stoku fliszowego na Stacji Badawczej IGIPZ PAN w Szymbarku w latach 2000-2015

67%
Bochenek W.
Acta Agrophysica
|
2016
|
tom 23
|
nr 3
W artykule przedstawiono dynamikę zasobności wody w pokrywach stokowych w oparciu o wielkość wskaźnika zagrożenia suszą gruntową kn, obliczonego dla okresów 10- lub 11-dniowych na podstawie codziennych pomiarów stanów wody na stanowiskach piezometrycznych w środkowej i dolnej części pogórskiego stoku fliszowego w Szymbarku. Na obydwu stanowiskach zainstalowane zostały po cztery otwory piezometryczne o głębokości 50, 100, 150 i 250 cm, w których dokonywano pomiarów za pomocą gwizdka studziennego (świstawki). Na podstawie pomiarów przeprowadzonych w latach 2000-2015 stwierdzono występowanie umiarkowanych i dość silnych zależności miedzy średnimi rocznymi stanami wody a sumami opadów i warstwą odpływu. Największą liczebność dekadowych wyników wskaźnika kn stwierdzono w klasie "zagrożenie niżówką"(–0,1 < kn <= 0,1) lub w klasie "brak zagrożenia niżówką" (0,1 < kn <= 0,3). Najczęściej zagrożenie niżówką występowało w piezometrach o głębokości 1,5 m. Najdłuższe okresy niżówki gruntowej (kn < –0.1), obliczonej dla wszystkich otworów na danym stanowisku, trwały dziewięć dekad, zaś najdłuższe okresy nadmiaru wody (kn > 0,3) na obydwu stanowiskach trwały przez pięć dekad. W ciągu roku występuje wzrost wskaźnika kn we wszystkich otworach piezometrycznych między trzecią dekadą lutego a pierwszą dekadą kwietnia, będący efektem zasilania przez opady w okresie zimowym, w tym topnienie pokrywy śnieżnej, w warunkach ograniczonej ewapotranspiracji i odpływu korytowego.
16
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Changes in Atlantic water characteristics in the South-Eastern Mediterranean Sea as a result of natural and anthropogenic activities

67%
Said M. A., Gerges M. A., Maiyza I. A., Hussein M. A., Radwan A. A.
Oceanologia
|
2011
|
tom 53
|
nr 1
17
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Quantity of selected physical and chemical parameters in surface microlayers and subsurface water on the example of three lakes

67%
Antonowicz J.
Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline
|
2008
|
tom 12
For the period of 4 years, in quarter-time cycle, samples had been taken from surface microlayers and subsurface water of the lakes: Gardno, Jasień and Dołgie Wielkie, by two techniques (Garret net and glass plate). In each talked over layers we have analyzed contents of calcium, general alka-linity, conductance and water reaction (pH). We have also determined the ability of surface mi-crolayer to accumulate these components and we have compared it to subsurface water ability and verified whether this ability depends on the kind of the lake.
18

Phylogenetic diversity and abundance of bacteria from surface microlayer and subsurface water in eutrophic lake

67%
Walczak M., Swiontek Brzezinska M.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 1
The bacteria from different phylogenetic groups were studied in surface microlayer (SM, up to 100 μm) versus subsurface water (SW – 20 cm) in eutrophic lake from spring to autumn of 2007. Abundance of bacteria was determined using a combination of direct counting of 4’, 6-diamidino-2-phenylindole and the phylogenetic diversity was determined in fluorescence in situ hybridization (FISH) method with group-specific, fluorescently labeled oligonucleotide probes. The numbers of DAPI bacteria varied between 4.75 and fluorescence in situ hybridization (FISH) demonstrated that Eubacteria constituted the majority of the whole bacterial population and their percentage share ranged from 59 to 75%. Abundances of alpha- beta-Proteobacteria and Cytophaga-Flavobacteria groups varied across seasons, layers, and lacustrine zones. The lowest number of alphaProteobacteria group bacteria was observed in spring (SM – 0.2 × 10⁶, SW – 0.16 × 10⁶ cells cm⁻³), whereas the highest in autumn (SM – 0.62 × 10⁶, SW – 1.6 × 10⁶ cells cm⁻³). The percentage share of these groups of bacteria in the Eubacteria domain was lower in spring (20–50%) than in summer and autumn (from 65 to over 80%). No fixed difference between the composition of SM and SW bacteria was noticed. Seasonally occurred changes are similar in both layers.
19

Chemical and bacteriological studies of surface and subsurface water layers in estuarine Lake Gardno

67%
Mudryk Z. J., Trojanowski J., Antonowicz J., Skorczewski P.
Polish Journal of Environmental Studies
|
2003
|
tom 12
|
nr 2
This paper presents results of chemical and bacteriological examinations of surface and subsurface water layers of estuarine lake Gardno. The obtained data indicate that there are substantial differences in chemical compound concentrations and also bacteria number and activity between the water layers under investigation. Particularly great differences between microlayers and subsurface water refer to concentrations of organic phosphorus and nitrogen. It was found that bacteria number was greater in surface water layers than in subsurface water. Significant differences among the studied chemical and bacteriological parameters were revealed between particular sites across lake Gardno. The number of freshwater, brackish and marine bacteria in the water of lake Gardno was up to chlorides concentration.
20

The impact of UV radiation on metabolism of neustonic and planktonic bacteria in eutrophic lake

59%
Burkowska A., Walczak M., Donderski W.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 2
The range of solar radiation reaching the air-water inter-phase, medium wave UV radiation, i.e. UVB 290–320 nm and UVA 320–400 nm, is of the highest biological importance due to its harmful effects. Radiation within this range causes DNA damage (lethal effect) or limits the growth of organisms by inhibiting enzyme synthesis, reducing active transport, or by inducing mutations. The studies were carried out in 2007 based on samples water collected from surface microlayer (SM) (up to 150 μm) and subsurface water (SSW) (25 cm) of pelagic zone of eutrophic lake. The representative collection of bacterial strains was isolated from collected samples. The following are measured: the DNA and cellular protein synthesis activity, respiration activity of the bacteria and activity of hydrolytic enzymes in control cultures, subjected to UVB radiation (applied dose 100 mW cm⁻²) and with and without humic substances (HS) (final concentration 100 mg L⁻¹) playing role of compounds potentially protective from UV radiation. UVB irradiation had the strongest inhibiting impact on production of DNA in bacterial cells (12–23% of that in non-irradiated samples). UVB radiation also inhibits the synthesis of cellular protein (27–43% of that in non-irradiated samples) and bacterial respiration activity (44–48%). UVB radiation had by far the lowest impact on the activity of hydrolytic enzymes. HS may function as a protective agent against UV radiation only in DNA synthesis. No significant differences in response to UVB were found between planktonic and neustonic bacteria.
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