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1

Rola oczyszczalni hydrobotanicznych w oczyszczaniu ścieków z terenów wiejskich

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

Woda-Środowisko-Obszary Wiejskie

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2010

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T. 10, z. 3

119-127

PL

Celem badań była ocena skuteczności oczyszczania ścieków bytowo-gospodarczych w małej przydomowej oczyszczalni wierzbowej oraz doczyszczania ścieków w gminnej, mechaniczno-biologicznej oczyszczalni z filtrem piaskowo-trzcinowym. Próbki ścieków do badań pobierano w okresie od maja do grudnia 2007 r. Liczebność bakterii heterotroficznych zdolnych do wzrostu w temperaturze 22°C (jtk 22°C) i 37°C (jtk 37°C) oznaczano metodą płytek lanych zgodnie z normą PN-ISO 6222. Liczebność bakterii z grupy coli (TC) oraz bakterii termotolerancyjnych (fekalnych) z grupy coli (FC) oznaczano metodą fermentacyjną probówkową zgodnie z PN-75/C-04615/05 i PN-77/C-04615/07. Liczebność paciorkowców kałowych [FS] badano metodą filtrów membranowych zgodnie z PN-82/C-04615/25 na podłożu Slanetza-Bertleya. Wykazano znaczne zmniejszenie liczebności większości badanych grup bakterii w trakcie oczyszczania ścieków metodą hydrobotaniczną. W najmniejszym stopniu zmniejszyła się liczebność paciorkowców kałowych.

EN

One of the ways to solve the sewage treatment problems in Polish rural areas is the use of unconventional sewage treatment systems based on ponds with macrophytes or on ground filters with hydrophytes. Their function follows the model of natural wetlands. They are featured by many merits and can be used to treat sewage from single farms, small villages, land estates or agro-tourist centres. Beside abiotic processes such as sedimentation and filtration, sorption of chemical pollutants in the medium and photolytic reactions, an important role in sewage treatment play biological factors - vascular flora and microorganisms in a given object. The aim of this study was to assess the effect of sewage treatment in a small home willow treatment plant and treated sewage polishing in the communal mechanical-biological treatment plant with sand-reed filter. The sewage for analyses was sampled from May to December 2007. The number of heterotrophic bacteria capable of growing at temperatures of 22°C (cfu 22°C) and 37°C (cfu 37°C) was estimated by cast plate method according to Polish standard PN-ISO 6222. The numbers of coliform bacteria [TC] and thermo-tolerant (faecal) coliform bacteria [FC] were estimated by means of fermentation test-tube method according to Polish standards PN-75/C-04615/05 and PN-77/C-04615/07. The number of faecal streptococci (FS) was determined by the membrane filter method according to Polish standard PN-82/C-04615/25 with the use of Slanetz-Bertley medium. Considerable reduction of the majority of investigated bacteria groups was found during hydrophyte sewage treatment. The lowest reduction was observed in the number of faecal streptococci.

2

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

Walczak M., Swiontek Brzezinska M.

Polish Journal of Ecology

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2010

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Vol. 58, nr 1

177-186

EN

The bacteria from different phylogenetic groups were studied in surface microlayer (SM, up to 100 [mu]m ) 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 alpha-Proteobacteria group bacteria was observed in spring (SM - 0.2 x 10[^6], SW - 0.16 x 10[^6] cells cm[^-3]), whereas the highest in autumn (SM - 0.62 x 10[^6], SW - 1.6 x 10[^6] 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.

3

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

Walczak M., Swiontek Brzezinska M.

Polish Journal of Ecology

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2009

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Vol. 57, nr 3

547-554

EN

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 [my]m) and subsurface water (SSW) (25 cm) in the typical eutrophic (TOC 5-15 mg dm[^-3]; chlorophyll 5-26 [my]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.

4

Degradation of chitin in natural environment : role of Actinomycetes

Swiontek Brzezinska M., Lalke-Porczyk E., Donderski W., Walczak M.

Polish Journal of Ecology

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2009

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Vol. 57, nr 2

229-238

EN

The actinomycetes in water samples and bottom sediments of lowland, eutrophic lake as well as in soil (farmland, sandy) of the lake basin were studied. Chitin-degrading actinomycetes were isolated (with a plate technique) from each habitat; subsequently, their chitinolytic activity (with the fluorometric method) was determined in relation to temperature (10-50[degree]C) and the physical type of chitinous substance (colloidal chitin, chitin powder, and shrimp shells). This study demonstrated that actinomycetes were the most abundant in soil samples (average of 18x10[^3] CFU g[^-1] in farmland soil, 9x10[^3] CFU g[^-1] in sandy soil), and the least abundant in water samples (average of 2.7x10[^1] CFU mL[^-1] in lake water at neutral pH, 0.6x10[^1] CFU mL[^-1] in lake water with alkaline pH). The highest percentage of chitinolytic actinomycetes was observed in soil (average of 80% in sandy soil and 85% in farmland soil). Chitinolytic actinomycetes also made up a large fraction of total actinomycetes in water samples (average of 73%). In silt and sandy sediments, percentages of chitinolytic actinomycetes equaled 23 and 15%, respectively. Actinomycetes collected in soil were characterized by the highest activity (average of 14 nmol MUF mg[^-1] of protein h[^-1] in farmland soil, 8.5 nmol MUF mg[^-1] protein h[^-1] in sandy soil). The lowest activity was observed among benthic actinomycetes (average of 5.4 nmol MUF mg[^-1] of protein h[^-1] in silt, 0.65 nmol MUF mg[^-1] protein h[^-1] in sandy sediments). The impact of temperature and the type of chitinous substrate on the activity of chitinases produced by actinomycetes demonstrated that their activity peaked at 40[degree]C and in the presence of colloidal chitin. Observed differences in actinomycetales number and activity in the lake and the soil may be explained by higher accumulation of chitin substances in the soil. This polymer allows microorganisms to continually synthesize chitinolytic enzymes and take active part in that compound decomposition.

5

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

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

Polish Journal of Ecology

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2008

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Vol. 56, nr 2

335-342

EN

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 O[2] g[^-1] protein in 5 days, the shrimp head sections - 851 mg O[2] g[^-1] protein in 5 days and shrimp exoskeletons - 490 mg O[2] g[^-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 O[2] g[^-1] protein in 5 days). Shrimp exoskeletons were oxidized the least efficiently (average 160 mg O[2] g[^-1] protein in 5 days). Certain strains were not using them at all.