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EN
Long-term changes in hydrochemistry and community structure of phytoplankton and macrophytes were analyzed in the Sestroretskiy Razliv reservoir (northwestern Russia). The average content of total phosphorus (TP) in May–October increased from 73 μg P l-1 in 1980 to 163 μg P l-1 in 2000. A significant increase in average chlorophyll a content from 16.6 μg l-1 in 1980 to 84.7 μg l-1 in 2000 and a shift in phytoplankton composition to the dominance of cyanobacteria over diatoms indicated a change in the trophic status of the reservoir from meso-eutrophic to hypertrophic. In 2016 and 2018, average TP was 96 and 101 μg P l-1, respectively. The average content of chlorophyll a was 43.6 μg l-1 in 2016 and 66.6 μg l-1 in warmer 2018, indicating persistent eutrophic conditions. Diatoms dominated both in 2016 and 2018, especially in 2016 characterized by unfavorable weather conditions. Cyanobacteria were more abundant in 2018 with higher summer temperatures. The decline of the total area covered by aquatic vegetation from 157 ha in 1980 to 76 ha in 2016 likely resulted from an increase in phytoplankton biomass and water turbidity. Based on the results of our observations, in addition to further reduction in nutrient loading, biomanipulation by introducing predatory fish as a restoration measure was proposed to improve the ecological status of the reservoir.
EN
The study aimed at measuring the influence of a wide range of oxytetracycline concentrations, with particular attention to the low levels of the antibiotic on cyanobacteria Microcystis aeruginosa and Nodularia spumigena, diatom Phaeodactylum tricornutum and the model green algae Chlorella vulgaris by conducting prolonged toxicity tests (lasting 10 days). Standard measurements (cell number, optical density, chlorophyll a concentration) were combined with photosynthetic parameters measurements. The obtained results show that concentrations of oxytetracycline present in the environment can affect tested microorganisms. It was found to decrease photosystem II efficiency and disrupt the photosynthesis process. A careful interpretation of photosynthetic parameters allowed a better understanding of the mode of action of oxytetracycline in relation to non-target photoautotrophic organisms like cyanobacteria and microalgae. In conclusion, it would appear that the use of standard chronic toxicity tests (72 h) does not allow to accurately and reliably assess the chronic impact of bioactive compounds including drugs and their metabolites on water organisms. On this basis, we recommend the application of extended duration tests.
EN
The mean share of heterocystous cyanobacteria in total chlorophyll-a production in coastal waters, based on cyanobacterial marker carotenoid and chloropigments preserved in recent sediments (0-5 cm, ca 30 years), has been studied in the Gulf of Gdańsk (southern Baltic) and for comparison in the Oslofjord/Drammensfjord (southern Norway). First of all, Baltic cyanobacteria, both from laboratory cultures and field samples, were analysed to select marker heterocysteous cyanobacteria carotenoids for sediments. The pigment relation to diatom percentages of different salinity preferences has been tested, to confirm origin of cyanobacteria. The results indicate that canthaxanthin is the best marker of heterocystous cyanobacteria in the southern Baltic Sea. These filamentous cyanobacteria inflow to the Gulf of Gdańsk from the open sea and their abundance has increased in the last thirty years, in comparison with previous time. In that period they made up ca 4.6% of the total chlorophyll-a production in the Gulf of Gdańsk. The estimate for Oslofjord, at the same assumptions, suggests that heterocystous cyanobacteria occurred there also (up to 5.8% of the total chlorophyll-a production), were of marine origin, but their abundance has decreased during the last thirty years. Such an estimate may be used in environmental modelling and can be applied to other coastal areas, once the marker pigments of the main cyanobacteria species have been identified, and the percentage of total chlorophyll-a produced in a basin, preserved in sediments, has been determined for such area.
EN
The purpose of the presented research is to analyse possible methods of thickening of the Microcystis aeruginosa (Kützing) Kützing cyanobacteria using the obtained concentrate as a biomass for the production of energy carriers and biologically valuable substances. Method of cyanobacteria thickening under the action of electric current and in the electric field, as well as the method of coagulation–flocculation and gravity thickening, was experimentally investigated in labscale conditions. Electrical methods didn't show positive results for the Microcystis aeruginosa thickening, despite the reports of their potential efficiency in a number of previous studies. The high efficiency of the method of coagulation– flocculation and gravity thickening of Microcystis aeruginosa suspensions was obtained. The optimum concentrations of industrial polymeric coagulants and flocculants for the thickening of Microcystis aeruginosa suspensions were defined in the range of about 10 ppm for the coagulants and about 1 ppm for the flocculants. Negative effect of the previous cavitational treatment of the diluted suspensions of Microcystis aeruginosa on the effectiveness of the coagulation–flocculation and gravitational thickening was confirmed experimentally. Hydrodynamic cavitation should be recommended to use after the thickening as the next step of processing of concentrated suspensions of Microcystis aeruginosa to achieve maximum extraction of energy carriers and biologically valuable substances.
PL
Celem przedstawionych badań była analiza możliwych metod zagęszczania cyjanobakterii Microcystis aeruginosa (Kützing) Kützing do uzyskania koncentratu biomasy przydatnego do produkcji energii i substancji czynnych biologicznie. W skali laboratoryjnej analizowano metody zagęszczania pod wpływem prądu i pola elektrycznego oraz metody koagulacji– flokulacji i zagęszczania grawitacyjnego. Metody elektryczne nie dały pozytywnych wyników mimo wielu wcześniejszych badań na temat ich potencjalnej efektywności. Dużą efektywność uzyskano natomiast w przypadku metod koagulacji– flokulacji i grawitacyjnego zagęszczania zawiesiny Microcystis aeruginosa. Optymalne stężenie przemysłowych polimerowych koagulantów użytych do zagęszczania ustalono na 10 ppm, a flokulantów – na 1 ppm. Doświadczalnie potwierdzono ujemny wpływ wcześniejszego poddawania rozcieńczonych roztworów Microcystis aeruginosa działaniu kawitacji na skuteczność zagęszczania metodami koagulacji i flokulacji oraz zagęszczania grawitacyjnego. Hydrodynamiczną kawitację zaleca się stosować po zagęszczaniu, jako następny etap w przetwarzaniu zagęszczonej zawiesiny Microcystis aeruginosa do postaci nośnika energii i pozyskania substancji biologicznie czynnych.
EN
At present, harmful cyanobacterial efflorescence in Algerian water bodies used for drinking water are dominant throughout the year and their management requires a better knowledge of the cyanobacteria dynamics and the environmental parameters related to their dominance. The Ain Zada reservoir is a home of 5 genera. The occurrence frequency estimation of the identified genera shows the constancy of Planktothrix, the regularity of Aphanizomenon, Pseudanabaena and Cylindrospermopsis and the rarity of Oscillatoria. The dominant genus Planktothrix is represented exclusively by Planktothrix agardhii; this species showed the highest proportion rates in winter (95.61%), spring (94.80%) and autumn (80.29%) and the lowest in summer (29.16%). Planktothrix agardii abundances show positive relation with suspended solids and chlorophyll a and negative relation with the depth of Secchi disc. The blooms of the potential toxinogenic Planktothrix agardhii and Cylindrospermopsis are related negatively. The results from cyanotoxins and pigments characterization showed a strong positive relation of Planktothrix agardhii abundance with microcystins (MCs) and phycocyanin (PC) concentrations. Indeed, in Ain Zada dam, we found that MCs contents have positive relation with water temperature and pH and a negative relation with NO3. Our results show that – except for the months of March, October and November – the monthly abundances of cyanobacterial population recorded in Ain Zada dam exceeded the alert level 2. The filamentous species found in this dam are of great concern, as they are able to synthesize toxins harmful to aquatic and terrestrial organisms. Further research is needed to confirm the presence of other cyanotoxins (e.g. cylindrospermopsin) in Ain Zada dam.
PL
Przedstawiono innowacyjną, kompleksową technologię usuwania osadów dennych i ich przetwarzanie na nawóz organiczno-mineralny, o właściwościach zbliżonych do obornika. Zastosowanie tej technologii zapobiega eutrofizacji wody w zbiorniku, a ponadto przyczynia się do spełnienia wymagań Unii Europejskiej i przepisów krajowych dotyczących poprawy parametrów sanitarnych zasobów wody powierzchniowej. Dodatkowo, stwarza możliwości poprawy stanu gleb w Polsce dzięki dostarczeniu węgla organicznego, którego ubytek stwierdzono m.in. również w glebach UE.
EN
Therefore, an innovative, comprehensive technology for removing bottom sediments and their processing into an organic-mineral fertilizer with properties similar to manure has been developed. The use of this technology prevents the eutrophication of water in the reservoir, and moreover contributes to the fulfillment of Poland’s obligations towards the European Union and the National Regulations regarding the improvement of sanitary parameters of surface water resources. In addition, it creates opportunities to improve the condition of soils in Poland thanks to the supply of organic carbon, the loss of which has been found, among others also in EU- soils.
PL
Przedstawiono innowacyjną, kompleksową technologię usuwania osadów dennych i ich przetwarzanie na nawóz organiczno-mineralny, o właściwościach zbliżonych do obornika. Zastosowanie tej technologii zapobiega eutrofizacji wody w zbiorniku, a ponadto przyczynia się do spełnienia wymagań Unii Europejskiej i przepisów krajowych dotyczących poprawy parametrów sanitarnych zasobów wody powierzchniowej. Dodatkowo, stwarza możliwości poprawy stanu gleb w Polsce dzięki dostarczeniu węgla organicznego, którego ubytek stwierdzono m.in. również w glebach UE.
EN
Therefore, an innovative, comprehensive technology for removing bottom sediments and their processing into an organic-mineral fertilizer with properties similar to manure has been developed. The use of this technology prevents the eutrophication of water in the reservoir, and moreover contributes to the fulfillment of Poland’s obligations towards the European Union and the National Regulations regarding the improvement of sanitary parameters of surface water resources. In addition, it creates opportunities to improve the condition of soils in Poland thanks to the supply of organic carbon, the loss of which has been found, among others also in EU-soils.
PL
Zakwit sinic to masowy rozwój glonów planktonowych, który powoduje zmianę zabarwienia wody, pogorszenie jej jakości, smaku i zapachu oraz obumieranie organizmów wodnych. Sinice są organizmami, które mają dużą zdolność przystosowywania się do otaczających je warunków środowiskowych. Posiadają one charakterystyczną dla nich strukturę, w której znajdują się wakuole gazowe w postaci pęcherzyków wypełnionych powietrzem znajdującymi się wewnątrz komórki. W pracy przedstawiono technologię mechanicznego usuwania zakwitów sinicowych z powierzchni akwenów wodnych, z wykorzystaniem pływającego urządzenia.
EN
Cyanobacterial bloom is a massive development of planktonic algae, which causes a change in water colour, deterioration of its quality, taste and smell, and death of aquatic organisms. Cyanobacteria are organisms that have a high capacity of adapting to the surrounding environmental conditions. They have a characteristic structure, which includes gas vacuoles in the form of bubbles filled with air inside the cell. The paper presents the technology of mechanical removal of cyanobacterial blooms from the surface of water reservoirs using a floating device.
PL
Przeprowadzone badania miały na celu określenie możliwości zastosowania ścieków pochodzących z przydomowej oczyszczalni do hodowli mikroglonów Chlorella vulgaris i cyjanobakterii Arthrospira platensis. Przeprowadzone badania potwierdziły możliwość zastosowania omawianych ścieków do hodowli mikroglonów Chlorella vulgaris i cyjanobakterii Arthrospira platensis. Związki biogenne zawarte w ściekach z powodzeniem były wykorzystywane przez glony i cyjanobakterie, co pozwoliło na ich skuteczne usunięcie. W przypadku Chlorella vulgaris dostarczenie ścieków bez dodatkowej suplementacji gwarantowało prowadzenie efektywnej hodowli. W przypadku cyjanobakterii Arthrospira platensis hodowla była możliwa jedynie z zastosowaniem suplementacji w postaci NaHCO3 oraz Na2CO3. Najwyższą efektywność usuwania zarówno związków azotu jak i fosforu uzyskano w hodowli Chlorella vulgaris, które wynosiły odpowiednio 98.5 ± 0.59% i 97.18 ± 0.76%.
EN
The research aimed at determining the possibility of using effluent from the domestic treatment plant for cultivating microalgae Chlorella vulgaris and cyanobacteria Arthrospira platensis. The conducted research confirmed the possibility of using the effluent for cultivation of microalgae Chlorella vulgaris and cyanobacteria Arthrospira platensis. Biogenic compounds contained in wastewater were successfully used by algae and cyanobacteria, which allowed their effective removal. Biomass growth of Chlorella vulgaris was obtained by using effluent without additional supplementation. In the case of cyanobacteria Arthrospira platensis biomass growth was possible only with supplementation in the form of NaHCO3 and Na2CO3. The highest efficiency of removing nitrogen and phosphorus compounds was obtained in the cultivation of Chlorella vulgaris, which were respectively 98.5 ± 0.59% and 97.18 ± 0.76%.
PL
Jednym ze sposobów pozyskania surowca na cele fermentacji metanowej, jak również w innych gałęziach energetyki alternatywnej, jest wykorzystanie biomasy alg oraz cyjanobakterii. Charakteryzują się one dużo szybszym współczynnikiem przyrostu biomasy w stosunku do roślinności lądowej, a także potrzebują znacznie mniejszą powierzchnię przeznaczoną na hodowlę. Celem podjętego zagadnienia badawczego było określenie możliwości poddania procesowi fermentacji metanowej biomasy glonów z gatunku Chlorella vulgaris, Platymonas subcordiformis, Botryococcus braunii oraz biomasy cyjanobakterii z gatunku Arthrospira platensis. Beztlenowy rozkład substratu w postaci mikroglonów Platymonas subcordiformis pozwolił na osiągnięcie współczynnika produkcji biogazu na poziomie 451 ±11 cm3gs.m.-1. Zbliżoną wartość produkcji biogazu uzyskano w przypadku fermentacji metanowej cyjanobakterii z gatunku Arthrospira platensis oraz mikroglonów z gatunku Chlorella vulgaris wynosząca odpowiednio 447±10 cm3gs.m.-1 i 447±14 cm3gs.m.-1. Najniższym współczynnikiem produkcji biogazu charakteryzował się beztlenowy rozkład glonów z gatunku Botryococcus braunii, w przypadku którego uzyskano wartość na poziomie 314 ±12 cm3gs.m.-1.
EN
One of the methods of obtaining the substrate for methane fermentation and other alternative energy sectors is the use of biomass of microalgae and cyanobacteria. This microorganisms have a high biomass growth rate compared to terrestrial plants and need less area for cultivation. The aim of the research was to determine the possibility of methane fermentation of biomass of Chlorella vulgaris, Platymonas subcordiformis, Botryococcus braunii and cyanobacteria Arthrospira platensis. The methane fermentation of the Platymonas subcordiformis microalgae allowed to achieve a biogas production coefficient of 451 ±11 cm3 · g TS-1. A similar value of biogas production was obtained in the methane fermentation of Arthrospira platensis and Chlorella vulgaris, amounting to 447 ±10 cm3 · g TS-1 and 447 ±14 cm3 · g TS-1, respectively. The lowest biogas production coefficient was characterized by the methane fermentation of Botryococcus braunii algae, where the value reached 314±12 cm3 · g TS-1.
EN
Cyanobacteria constitute a rich source of biologically active and structurally diverse compounds. The pharmacological potential of these compounds resides among others in their ability to control the proliferation and growth of cancer cell lines and potent disease-causing microbial agents. Despite recent scientific advances, the way these compounds interact with the body’s molecular structure are still unclear and science still has to discover how the cyanobacterial metabolites interact with cell structures and how cells react to them. In this project, we will study yet unexamined cyanobacterial metabolites, especially the compounds which act as chemical ligands for microRNA (miRNA) -binding sites, making them promising regulators (inhibitors) of gene networks that are involved in various diseases. We will first develop a stable cell line that constitutively expresses a unique miRNA reporter system. Then, we will conduct a screen on chemical compounds discovered in Baltic cyanobacteria to identify small molecules with inhibitory activity and specificity to MIR92b-3p, which has a significant impact on liver cell behavior in humans. We assume that a successful MIR92b-3p inhibitor will bind to the precursors of MIR92b-3p miRNA, disabling the action of either of the two processing enzymes involved in the biogenesis of any miRNA in a cell (Drosha or Dicer), thus affecting the MIR92b function. The discoveries made with these inhibitory chemical molecules could provide insight into the role of the MIR92 pathway in liver diseases and cancer, and possibly, if promising results appear, they may facilitate a strategy for treating some human diseases in the future.
EN
Phosphatized biomorphs, resembling modern and ancient bacteria, were identified for the first time in phosphate nodules, present at the base of the Bílá Hora Formation (uppermost Cenomanian - lower Turonian), and in phosphate coprolites at the base of the Teplice Formation (upper Turonian) in the Bohemian Cretaceous Basin. They are present in colonies as filaments, coccoids, strings, rods and outgrowths, associated with the phosphate as part of the rock constituents and display the characteristics of fossilized bacteria. Two types of bacteria were identified: chemotrophic, sulphur-reducing bacteria in the phosphate nodules and phototrophic cyanobacteria in the phosphate coprolites. Microanalysis of some of the fossil bacteria revealed a fluoride-rich calcium phosphate composition, compatible with the composition of bulk samples, in which carbonate-fluorapatite is the main mineral in the phosphate nodules and coprolites. The environmental indications of these fossil bacteria support the interpretation of an anoxic environment of phosphogenesis in the latest Cenomanian - earliest Turonian and variable redox conditions of coprolite phosphatization in the late Turonian. The potential microbial role in phosphogenesis in the former may have involved the suboxic breakdown of P-rich organic matter by sulphur-reducing bacteria and the release of phosphorus in the pore water, leading to the biochemical precipitation of phosphate. The latter involved initial P-storage by phototrophic bacteria in an oxic environment, followed by P-release below the sediment-water interface under suboxic conditions and subsequent phosphatization of the coprolites.
EN
A mathematical model of the mechanism of the appearance of antisymmetric vortices during the propagation of freshwater into the seawater which is observed, in particular, at the exit from the Baltic Canal connecting the Vistula Lagoon and the Baltic Sea is constructed in the work. In particular it is shown that the main reason for the vortex formation in this case is the Coriolis force. The exact dependence of the circulation of velocity on time for the three simplest types of the “tongue” of the intrusion of freshwater is calculated analytically in the work as well.
14
Content available Biophotonics for biofuel upgradation
EN
Experimental studies have been made to find out Cyanobacterias’ biophotonical response in gaseousfuelation and car-bon dioxide fixation during photo-anaerobic digestion. A new horizontal type photo-bioreactor has been designed by using environment hazard plastic bottles and it works ideally for anoxygenic cyanobacterial growth. Through ‘V3-metagenomics’ of 16S rRNA gene sequencing by paired-end Illumina MiSeq and downstream analysis by QIIME program, we have identified anaerobic cyanobacteria, represent the orders YS2 and Streptophyta. OTUs have been identified by aligning against Greengenes and Silva databases, separately. The flame temperature of the fuel gas is 860°C and the percentcontent of carbon dioxide (CO2) is 17.6%.
PL
Badania doświadczalne przeprowadzono w celu określenia biofotonicznej zdolnośći cyjanobakterii do przeprowadzania reakcji uwalniania gazów do paliw oraz wiązania dwutlenku węgla podczas fotofermentacji beztlenowej. Nowy bioreaktor typu horyzontalnego został zaprojektowany przy użyciu zagrażających środowisku plastikowych butelek i działa/nadaje się idealnie dla beztlenowego wzrostu cyjanobakterii. Poprzez metagenomikę regionu V3 genu kodującego 16 S rRNA sekwencjonowanego poprzez sparowanie odczyty przy użyciu Illumina MiSeq oraz analizy downstream za pomocą programu QIIME zidentyfikowaliśmy beztlenowe cyjanobakterie, reprezentowane przez YS2 i Streptophyta. OTU (ang. Operational Taxonomic Unit) zostały zidentyfikowane przez wyrównywanie względem baz danych Greengenes i Silva oddzielnie. Temperatura płomienia w paliwie wynosi 860°C, a procentowa zawartość dwutlenku węgla (CO2) wynosi 17,6%.
EN
The issues presented in this study concern a very important problem of the occurrence of cyanobacterial blooms in surface water used for water supply purposes. The objective of this study was to analyze the occurrence of cyanotoxic risk in the catchment area of the Obrzyca River (including Sławskie lake which is the beginning of the river), which is a source of drinking water for the inhabitants of Zielona Góra. In order to evaluate toxicity of cyanobacterial bloom it was conducted toxicological testing using aquatic invertebrates (Daphnia magna, Dugesia tigrina) and heterotrophic bacteria (Escherichia coli, Enterococcus faecalis, Pseudomonas fluorescens). Test samples were collected from May to October, 2012. The most toxic was a sample collected from Lake Sławskie on 20th October when cyanobacteria bloom with a predominance of Microcystis aeruginosa occurred and the amount of microcystins was the largest. The methanol extract of the sample was toxic only above a concentration of 6x103 μgxdm-3. The lethal concentration (48-h LC 50) for Daphnia magna was 3.09x103 and for Dugesia tigrina (240-h LC 50) 1.51x103μgxdm-3 of microcystins (MC-LR, MC-YR and C-RR). The same extract stimulated growth of Escherichia coli and Enterococcus faecalis cells.
PL
Zagadnienia przedstawione w niniejszym artykule dotyczą bardzo ważnego problemu występowania zakwitów sinic w wodach powierzchniowych wykorzystywanych do celów wodociągowych. Celem pracy była ocena cyjanotoksycznego ryzyka w zlewni rzeki Obrzyca (w tym jeziora Sławskiego będącego początkiem rzeki), która jest źródłem wody do picia dla mieszkańców Zielonej Góry. W celu oceny toksyczności sinic przeprowadzono badania toksykologiczne przy użyciu bezkręgowców wodnych (Daphnia magna i Dugesia tigrina) oraz bakterii heterotroficznych (Escherichia coli, Enterococcus faecalis, Pseudomonas fluorescens). Próbki do badań pobierano od maja do października w 2012 roku. Ekstrakt metanolowy z zakwitu sinic (dominacja gatunku Microcystis aeruginosa) w J. Sławskim, gdzie ilość mikrocystyn była największa, był toksyczny dopiero po zatężeniu do 6•103 μg•dm-3. Stężenie letalne (48-h LC 50) dla Daphnia magna wyniosło 3,09•103 a dla Dugesia tigrina (240-h LC 50) było równe 1,51•103 μg•dm-3 mikrocystyn (MC-LR, MC-YR i MC-RR). Ten sam ekstrakt stymulował wzrost komórek Escherichia coli i Enterococcus faecalis.
PL
Mieszaninę trzech monokultur Cyanobacteria (Anabaena sp. Trebon, Microcystis aeruginosa MKR 0105, Anabaena variabilis) oraz dwóch handlowych biostymulatorów zastosowano w szerokim zakresie temp. (od –5°C do +40°C) i wilgotności 20% (zwiększonej do 60%) na glebę stosowaną do hodowli ślazowca pensylwańskiego. Dolistne stosowanie mieszanin Cyanobacteria i biostymulatorów znacznie zmniejszało hydrotermalny stres i korzystnie wpływało na wzrost i fizjologiczną aktywność roślin, zwiększało ich plon oraz mogło ograniczyć konieczność stosowania nawozów mineralnych oraz pestycydów.
EN
Mixts. of 3 strains of Cyanobacteria (Anabaena sp. Trebon, Microcystis aeruginosa MKR 0105, Anabaena variabilis) and 2 com. biostimulators were added to soil used for growing Sida hermaphrodita L. Rusby plants at temp. varying over a wide range (from –5°C to +40°C) applied at 3 week intervals (20% soil moisture) and excessive hydration (60%). Foliar application of Cyanobacteria mixts. and biostimulators significantly reduced the negative influence of hydrothermal stress and a positive influenced on the growth and physiol. activity of plants, increased the productivity of the plant, and can reduce the use of chem. fertilizers and pesticides.
EN
Secondary metabolites produced by plants, algae, bacteria and fungi may affect the growth and development of biological systems. This is a natural process which occurs worldwide and is known as allelopathy. A relatively small number of these allelopathic compounds has been identified. The majority of studies describe the inhibitory effect of investigated compounds, extracts, cell-free filtrates and living cells on other organisms, although stimulatory interactions have also been noticed. Allelopathic interactions in aquatic environments could provide a competitive advantage to some species over other primary producers. Furthermore, allelopathy occurs in all aquatic habitats and all groups of autotrophs are capable of producing and releasing allelopathically active compounds. Moreover, secondary metabolites obtained from phytoplankton could demonstrate other useful bioactive properties. This review is intended to summarize the current knowledge of allelopathic interactions between microalgae and cyanobacteria in aquatic environments, as well as to provide a brief overview of the ecological importance of these interactions and their potential practical application in different branches of industry
EN
The most numerous limestone caves are in the smallest national park in Poland (the Ojców National Park). A total of 50 algal samples were collected from ten caves, each having different environmental factors such as light intensity, temperature and humidity. The morphological and ecological variability of cyanobacteria and algae were studied using fresh samples, cultures grown on agar plates, and documented with TEM, SEM and LM. Light microscopic observations showed that aerophytic cyanobacteria were the most important component of the cave′s photosynthetic microflora. Among cyanobacteria, the following genera were frequently encountered: Aphanocapsa, Chroococcus, Gloeocapsa, Leptolyngbya, and Synechocystis. Whereas the green algal genera, Apatococcus and Klebsormidium, often occurred with Chlorella, Muriella, Neocystis and the diatoms, Orthoseira and Pinnularia. Most of the algal species appeared to be cosmopolitan, ubiquitous, had simple nutrition requirements and wide ecological tolerance (they reproduced rapidly and were easily adaptable to new conditions). The cave′s microhabitats offered relatively stable microclimatic conditions and they seemed to be responsible for the observed distribution of aerophytic algae and cyanobacteria. The Shannon-Wiener index (H′) ranged between 4.9 and 3.9, and the Kruskal-Wallis test showed that these differences were statistically significant.
EN
The objective of the studies included a complex of three reservoirs (upper, middle and lower Arturówek) which play an important recreational role for the residents of the Łódź city and the surrounding areas. The reservoirs were constructed on the Bzura River and are located in the area of the Łódź Hills Landscape Park. The river, the ecological status of which was defined as moderate, has a great influence on the quality of water in the Arturówek reservoirs. A total of 36 planktonic samples were collected in 2011-2013 during spring, summer and autumn seasons. During the studies, the selected physical and chemical parameters were measured. In addition to taxonomic analysis of Cyanobacteria and algae, the analyses of abundance and biomass of phytoplankton and the concentration of microcystins in water were conducted. In 2013, ecohydrological rehabilitation of the Arturówek reservoirs was carried out. Investment works included: removal of the bottom sediments to reduce internal loads, construction of buffer vegetation zones (ecotones) and sedimentation-biofiltration systems to reduce the amounts of pollutants flowing into reservoirs with rainwater. Significant changes in the structure of phytoplankton were observed in 2013. Every year, the disappearance of Cyanobacterial blooms was observed in favor of an increasing contribution of algae.
EN
The structure of phytoplankton communities of Lake Jeziorak was presented for the first time. The objective of our research was qualitative and quantitative analysis and bioindices of phytoplankton during and outside the tourist season. Analysis of phytoplankton assemblages were performed in 2011-2012. A total of 96 taxa were identified in Lake Jeziorak, mainly: Cyanobacteria - 20, Bacillariophyceae - 49, and Chlorophyta − 19. Biomass of the phytoplankton varied from 10 mg l−1 in October to 29 mg l−1 in May. In the whole research period, Cyanobacteria dominated and represented up to 68% of the total biomass. The cyanobacterial blooms were constantly observed. Biomass in the summer period was composed of filamentous Aphanizomenon gracile, Limnothrix redekei, Planktothrix agardhii and Pseudanabaena limnetica. Outside the holiday season, i.e. in autumn and spring, filamentous Cyanobacteria accompanied cryptomonads in phytoplankton. The species composition, the biomass of phytoplankton, and TSI indicate the hypertrophic conditions of the lake. Phytoplankton in Lake Jeziorak was in a state of equilibrium for almost the entire study period. S1 was a dominant group and its abundance and biomass did not change by more than 10%. There was no significant direct effect of the seasonal tourism impact on the development of phytoplankton in Lake Jeziorak
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