Wyniki wyszukiwania - AGRO

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Diversity of macrophytes in Lake Rotcze in the Leczna-Wlodawa Lakeland

100%

Sender J.

Teka Komisji Ochrony i Kształtowania Środowiska Przyrodniczego

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2004

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tom 01

2

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

100%

Walczak M.

Polish Journal of Ecology

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2008

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tom 56

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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.

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Vertical microzonation of psammon rotifers [Rotifera] in the psammolittoral habitat of an eutrophic lake

100%

Ejsmont-Karabin J.

Polish Journal of Ecology

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2008

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tom 56

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nr 2

351-357

Hydroarenal is a layer of submerged sands along the edge of a lake. Organisms living in interstitial spaces of this zone create a community called hydropsammon. Microzonation and seasonal dynamics of hydropsammon rotifers were studied in psammolittoral of deep, eutrophic Lake Mikołajskie (North-eastern Poland) in 2005. An aim of the study was to test the hypothesis that the top 0.5 cm of bottom sands (=epihydroarenal) plays a role of a transitory microzone between adjacent water layer and a deeper 1.5 cm layer of sands (=endohydroarenal). Sampling cores were taken at a station 1.5 m from water’s edge once or twice a month since April till October 2005. Three samples were taken: 5-cm thick water layer (AWL – adjacent water layer), 0.5-cm thick layer of water and sand from the transitory level (EPIH – epihydropsammon) and 2-cm thick slice of sand (ENDOH – endohydropsammon). From 94 species found in the lake 15% were restricted to AWL, 20% to endohydropsammon and only 5% to epihydropsammon. From 57 species found in epihydroarenal 52 (91%) were common with neighboring microlayers, i.e. AWL and endohydroarenal. The highest rotifer densities were noted in the endohydroarenal zone if expressed in area units. However, the rotifer densities in epipsammon if expressed in the same volume of occupied environment were ca 40 times higher than in adjacent water and about twice of those noted in endohydroarenal. This may suggest that epihydroarenal plays a role of both a transitory zone and a refugium for animals from adjacent water layer. Reasons for this phenomenon are still not clear

4

The concentration of mercury in the aquatic plants in Wadag Lake on Olstynian Lakeland

100%

Grzybowski M.

Biological Bulletin of Poznań. Supplement

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1996

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tom 33

5

Influence of some heavy metals on the survival of heterotrophic bacteria in bottom sediments of eutrophic lake

100%

Niewolak S., Kopij H., Chomutowska H.

Polish Journal of Environmental Studies

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1996

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tom 05

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nr 4

The influence of different concentrations (1-2000 ppm) of Sn, Cd, Mn, Cu, Ni, Co, Pb, Zn and Hg on the survival of heterotrophic bacteria in bottom sediments of a eutrophic lake of gyttja type was examined. Cl, NO3 and SO4 salts were used in the experiment. Co, Ni and Ag were the least toxic heavy metals for heterotrophic bacteria of the bottom sediments of the eutrophic lake, whereas Hg, Sn, Pb, Cu and Mn were more toxic and Cd and Zn were the most toxic. In the presence of the toxic metals the percent of surviving heterotrophic bacteria decreased with the increase of the concentration of metals. Death curves of these microbes were very close to the sigmoidal curve. Mathematical analysis of research results showed the existance of co-interaction of Sn, Cd, Mn, Cu, Ni and Ag concentrations and the time of experiment on the mean number of heterotrophic bacteria in the examined samples of the bottom sediments of the eutrophic lake. The time of metal contact influences the amount of heterotrophic bacteria of the bottom sediments at a lower degree than its concentration.

6

The concentration of Fe in the aquatic plants in Wadag Lake on Olstynian Lakeland

100%

Grzybowski M.

Biological Bulletin of Poznań. Supplement

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1996

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tom 33

7

The concentration of Cd in the aquatic plants in Wadag Lake on Olstynian Lakeland

100%

Endler Z., Grzybowski M.

Biological Bulletin of Poznań. Supplement

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1996

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tom 33

8

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Habitat diversity of some lakes in the Lublin Polesie Region

100%

Adamczuk M.

Acta Agrophysica

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2002

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tom 67

9

The concentration of Cu in the aquatic plants in Wadag Lake on Olstynian Lakeland

100%

Grzybowski M.

Biological Bulletin of Poznań. Supplement

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1996

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tom 33

10

Impact of humic substances on bacterioplankton in eutrophic lake

100%

Burkowska A., Donderski W.

Polish Journal of Ecology

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2007

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tom 55

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nr 1

This paper presents the results of resarch on impact of humic substances (HS) on bacterioplancton in eutrophic Lake Jeziorak (north-eastern Poland). In cultures of natural bacteria from the lake water, enriched with 0, 5, 10, 25 and 50 mg dm⁻³ of HS (natural HS – isolated from lake water or commercial HS – sodium salt of humic substance; Sigma-Aldrich), were determined the following parameters: total number of bacteria (TNB), number of heterotrophic bacteria (CFU), bacterial production (BP) (measured with [³H]methyl thymidine method) and general activity of esterases. Natural HS had a more positive impact on bacterial growth, bacterial production and activity of esterases than the commercial preparation HS. The highest TNB and CFU was observed when the water was enriched with 25 mg dm⁻³ of natural HS. All concentrations of the natural HS stimulated bacterial production. The activity of hydrolytic enzymes increased with rising concentrations of natural HS.

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Factors controlling the evolution of salinity, productivity and ecological stability of eutrophic lakes in cenral North America. (A summary)

84%

Barica J.

Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu

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1990

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tom 43

12

Size spectra and abundance of periphytic ciliate communities in small eutrophic lake (eastern Poland)

84%

Mieczan T.

Teka Komisji Ochrony i Kształtowania Środowiska Przyrodniczego

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2013

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tom 10

13

The role of chitinolytic bacteria and fungi in biodegradation of crustacean remains in lacustrine habitats

84%

Swiontek B. M., Lalke-Porczyk E., Donderski W.

Polish Journal of Ecology

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2008

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tom 56

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nr 2

335-342

This study presents results of research on occurrence of chitinolytic bacteria and fungi in water, bottom sediments, and watershed soil of an eutrophic lake and on their ability to use the crustacean skeletons (shrimp waste) as a respiration substrate. It was found that the respiration rate of bacteria and fungi during decomposition of chitin varied in different environments. The participation of chitinolytic microorganisms in water (13%) and soil (18%) was greater than in bottom sediments (5%). The respiration activity in the presence of all parts of shrimp waste and shrimp exoskeletons observed in chitinolytic bacteria was higher than that of fungi. But fungi demonstrated the highest metabolic activity in the presence of the shrimp head sections. The highest respiration activity was observed in planktonic and soil bacteria, while the lowest, in benthic strains. The chitinolytic bacteria used well all examined respiration substrates (all parts of shrimp waste – 671 mg O₂ r⁻¹ protein in 5 days, the shrimp head sections – 851 mg O₂ r⁻¹ protein in 5 days and shrimp exoskeletons – 490 mg O₂ r⁻¹ protein in 5 days). No significant differences in respiration activity were observed in chitinolytic fungi isolated from water, bottom sediments and soil. All of fungal strains demonstrated the highest metabolic activity in the presence of the shrimp head sections (average 1083 mg O₂ r⁻¹ protein in 5 days). Shrimp exoskeletons were oxidized the least efficiently (average 160 mg O₂ r⁻¹ protein in 5 days). Certain strains were not using them at all.

14

Planktonic rotifers of three eutrophic lakes of Leczynsko-Wlodawskie Lakeland (eastern Poland)

84%

Demetraki-Paleolog A., Sender J.

Teka Komisji Ochrony i Kształtowania Środowiska Przyrodniczego

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2013

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tom 10

15

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

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2013

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tom 22

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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.

16

Role of psammon microinvertebrates in phosphorus cycling in hydroarenal of an eutrophic lake

84%

Ejsmont-Karabin J., Gorelysheva Z., Kalinowska K., Rybak J. I.

Polish Journal of Ecology

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2012

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tom 60

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nr 3

Inorganic phosphorus released from littoral bottom sediments plays significant role in phosphorus budget of a whole ecosystem. An aim of the study was to assess a role of small invertebrates in phosphorus remineralization in hydroarenal (See Fig.1 in Preface). Hydropsammon organisms (i.e. bacteria, algae, ciliates, rotifers and crustaceans) living in a layer of submerged sands along the edge of a lake (=hydroarenal) were studied in psammolittoral of the deep, eutrophic Lake Mikołajskie (North-eastern Poland) in 2005. Sampling cores were taken at a station 1.5 m from water’s edge once or twice a month since April until October 2005. Each time three samples were taken: 5-cm thick water layer (AWL – adjacent water layer), 0.5-cm thick layer of water and sand from the transitory level (EPIH – epihydroarenal) and 2-cm thick slice of sand (ENDOH – endohydroarenal). The rate of phosphorus excretion was calculated using the appropriate regression equations expressing the relation between individual weight of organism and P excretion adjusted to the ambient temperature. Phosphorus remineralization by the psammon community (calculated for all ciliates, rotifers and crustaceans) was ca. 10 times higher than the maximum rate noted in lake pelagial. The most important role in the process was played by small ciliates, and in periods of high remineralization rate – by small cladocerans. Omnivores, feeding mostly on bacteria and small algae, played the most important role in all three studied layers, especially in periods of the highest rate of P remineralization, thus all kinds of food were used and mineralized. Predators do not seem to play significant role in P remineralization. In hydroarenal significant role seems to be played by processes involved in microbial loop. This suggestion is supported by strong domination of ciliates, main consumers of nanoflagellates, in the process of P remineralization. It seems that phytopsammon and psammic bacteria demands for phosphorus cannot be satisfied merely through the in situ remineralization by microinvertebrates.

17

Species diversity of yeast-like fungi in some eutrophic lakes in Olsztyn

84%

Biedunkiewicz A., Dynowska M., Ejdys E., Sucharzewska E.

Acta Mycologica

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2013

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tom 48

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nr 1

The study is part of hydromycological investigations of man-affected water bodies in Olsztyn. Our results show that yeast-like fungi are permanent components in three selected lakes (lakes Tursko, Długie and Skanda). Their abundance and species composition depend on the trophic state of each lake.

18

Small water bodies and lakes protected under EU Habitats Directive - results of the pilot wildlife monitoring in the Lubelskie region

84%

Peczula W., Banach B.

Teka Komisji Ochrony i Kształtowania Środowiska Przyrodniczego

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2013

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tom 10

19

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

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tom 57

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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.

20

Chironomid assamblages of mezo/eutrophic, macrophyte dominated Lake Skomielno (Western Polesie region, Eastern Poland) - palaeolimnological approach

84%

Kaczorowska A., Suchora M.

Teka Komisji Ochrony i Kształtowania Środowiska Przyrodniczego

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2014

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tom 11

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