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Wyszukujesz frazę "blue-green alga" wg kryterium: Temat


Wyświetlanie 1-5 z 5
Tytuł:
Influence of selected abiotic factors on the decomposition of chlorophylls
Autorzy:
Kowalewska, G.
Szymczak, M.
Powiązania:
https://bibliotekanauki.pl/articles/48301.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
chlorophyll
temperature
abiotic factor
blue-green alga
Anabaena variabilis
beta-carotene
decomposition
Opis:
The paper presents the results of experiments to determine the influence of selected physico-chemical factors – oxygen, visible light and temperature – on the decomposition of (1) chlorophylls a, b and c, chlorophyll a derivatives and β-carotene in acetone solution, and (2) chlorophyll a and β-carotene in axenic cultures of the blue-green algae Anabaena variabilis. The results indicate that both in acetone extracts and in blue-green algae cultures these pigments were most sensitive to light and oxygen; temperatures of up to 25◦C had no marked influence on these compounds. Under anoxia in acetone solution, the stability towards light decreased in the order chlorophyll a, chlorophyll b, chlorophylls c. Chlorophyll a, moreover, was less stable than its derivatives – phaeophorbides, phaeophytins, pyrophaeophytins and steryl chlorins – but more stable than β-carotene, in the last case also in the blue-green algae cultures. Decomposition of all the pigments proceeded mainly via the breakdown of the porphyrin macrocycle, since the decomposition products were not detected in the VIS range. On the basis of these experiments one can state that while light and oxygen may have a decisive direct influence on the distribution of chlorophylls and β-carotene in sediments, in the natural environment, temperatures of up to 25◦ C may have very little immediate effect.
Źródło:
Oceanologia; 2001, 43, 3; 315-328
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seasonal dynamics of phytoplankton in the inner Neva Estuary in the 1980s and 1990s
Autorzy:
Nikulina, V.N.
Powiązania:
https://bibliotekanauki.pl/articles/47983.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
species composition
biomass
Neva River
alga
blue-green alga
Oscillatoria
phytoplankton
Neva Estuary
seasonal dynamics
Opis:
The phytoplankton in the inner Neva Estuary is described from data obtained from 1996 to 2000.T he seasonal dynamics of the phytoplankton biomass are characterized by a bimodal curve with a summer maximum.T he average seasonal biomass was approximately 3 mg l−1, the maximum biomass was 8–11 mg l−1. The species composition and quantitative parameters were compared to those observed in the 1980s.A notable, nearly 1.5–2 fold, increase in the biomass in the summer–autumn period and the predominance of Oscillatoria species among the blue-green algae were observed.A decline in the nutrient load in the water body at the end of the 1990s appeared to be insufficient to bring about a decrease in the proportion of Oscillatoria algae in the total species composition or a decline in the biomass of the entire phytoplankton community. In 2000 a certain change in the structural composition of the phytoplankton complex was noted.S pecies that had been predominant in the 1980s and had lost their advantage in the early 1990s, regained their earlier status.
Źródło:
Oceanologia; 2003, 45, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Toxic cyanobacteria blooms in the Lithuanian part of the Curonian Lagoon
Autorzy:
Paldaviciene, A.
Mazur-Marzec, H.
Razinkovas, A.
Powiązania:
https://bibliotekanauki.pl/articles/48516.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
Baltic Sea
blue-green alga
Curonian Lagoon
Microcystis aeruginosa
Nodularia spumigena
Cyanoprokaryota
bloom
microcystin
Lithuania
nodularin
Opis:
The phenomenon of cyanobacteria (blue-green algae) blooms in the Baltic and the surrounding freshwater bodies has been known for several decades.The presence of cyanobacterial toxic metabolites in the Curonian Lagoon has been investigated and demonstrated for the first time in this work (2006–07). Microcystis aeruginosa was the most common and widely distributed species in the 2006 blooms. Nodularia spumigena was present in the northern part of the Curonian Lagoon, following the intrusion of brackish water from the Baltic Sea; this is the first time that this nodularin-(NOD)-producing cyanobacterium has been recorded in the lagoon.W ith the aid of high-performance liquid chromatography (HPLC), four microcystins (MC-LR, MC-RR, MC-LY, MC-YR) and nodularin were detected in 2006.T he presence of these cyanobacterial hepatotoxic cyclic peptides was additionally confirmed by enzyme-linked immunosorbent assay (ELISA) and protein phosphatase inhibition assay (PP1).Micr ocystin-LR, the most frequent of them, was present in every sample at quite high concentrations (from <0.1 to 134.2 μg dm−3).I n 2007, no cyanobacterial bloom was recorded and cyanotoxins were detected in only 4% of the investigated samples.A comparably high concentration of nodularin was detected in the northern part of the Curonian Lagoon.I n one sample dimethylated MC-RR was also detected (concentration 7.5 μg dm−3).
Źródło:
Oceanologia; 2009, 51, 2; 203-216
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of increasing uncontrolled recreation on the structure of plankton and macrophyte communities in the tunnel-valley lakes located in agricultural catchment area
Autorzy:
Kuczynska-Kippen, N
Messyasz, B.
Nagengast, B.
Powiązania:
https://bibliotekanauki.pl/articles/878149.pdf
Data publikacji:
2003
Wydawca:
Uniwersytet Przyrodniczy w Poznaniu
Tematy:
zooplankton
increasing eutrophication
tunnel-valley lake
blue-green alga
macrophyte community
plankton
agricultural catchment
phytoplankton
hydrobiology
catchment area
eutrophication
Opis:
In the years 1993-1995 biological research was carried out on three lakes, which are situated in a typical agricultural catchment area, along the Gołaniecka River. The hydrobiological examination carried out in 1993 revealed a stable state of eutrophy on these lakes. At that time neither of the Bukowieckie lakes was used for recreation, while at the Kobyleckie lake there were a number of buildings, including private holiday homes and holiday camps. In 1995, the year finishing the examination, recreation housing began to develop at the Bukowieckie Du?e lake and also an acceleration of tourism was observed on the Kobyleckie lake. In the spring and summer of 2000 hydrobiological research was repeated in order to find out whether the changes in the neighbourhood of the lakes had affected the chemical condition of lake waters. Although the building area by the lakes was still unfinished, particular changes of many parameters of water were already observed. Negative effects of trophic status were noted in the decrease of the visibility of water, increase of the nutrients concentration, in the outstanding blue-green algae character of the spring phytoplankton (Aphanizomenon issatschenkoi (Ussac.) Proschkina-Lavrenko; Planktothrix agardhii (Gom.) Anagn. et Kom.; Limnothrix redekei (Van Goor) Meffert) and zooplankton (Keratella cochlearis f. tecta (Lauterborn), K. quadrata (O.F. Müller), Anuraeopsis fissa (Gosse), Bosmina longirostris (O.F. Müller) and Chydorus sphaericus (O.F. Müller)), the increase of the total densities of zooplankton with the dominance of rotifers, the impoverishment of the phytolittoral, as well as quality and quantity changes in the structure of macrophytes.
W latach 1993-1995 przeprowadzono badania biologiczne na jeziorach: Bukowieckim Du- żym, Bukowieckim Małym i Kobyleckim, położonych w obrebie typowej zlewni rolniczej, wzdłuż Strugi Gołanieckiej. Badania hydrobiologiczne przeprowadzone w 1993 roku swiadczyły o stabilnym stanie eutrofii w tych jeziorach. W tym czasie ?adne z jezior Bukowieckich nie było wykorzystywane rekreacyjnie, podczas gdy nad Jeziorem Kobyleckim wystepowała zabudowa obejmujaca domki letniskowe i kempingi. W 1995 roku, po zakonczeniu badan, rozpoczeła sie budowa domków rekreacyjnych nad Jeziorem Bukowieckim Dużym, zaobserwowano także wzrost rekreacji nad Jeziorem Kobyleckim. W okresie wiosennym i letnim 2000 roku powtórzono badania hydrobiologiczne w celu stwierdzenia, czy zmiany w sasiedztwie jezior miały wpływ na parametry chemiczne ich wód. Chocia? zabudowa nad jeziorami nie była jeszcze zakonczona, zaobserwowano zmiany kilku parametrów wody badanych jezior (tab. 2). Głównym celem przeprowadzonych badan był opis istotnych zmian jakosciowych i ilosciowych parametrów fizyczno-chemicznych i biologicznych, ze szczególnym odniesieniem do aspektów dotyczacych wzrostu poziomu trofii badanych zbiorników. Negatywne efekty w stanie trofii były zwiazane ze zmniejszajaca sie przezroczystoscia wody, wzrostem koncentracji biogenów, wybitnie sinicowym charakterem fitoplanktonu wiosennego (Aphanizomenon issatschenkoi (Ussac.) Proschkina-Lavrenko; Planktothrix agardhii (Gom.) Anagn. et Kom.; Limnothrix redekei (Van Goor) Meffert) i zooplanktonem (Keratella cochlearis f. tecta (Lauterborn), K. quadrata (O. F. Müller), Anuraeopsis fissa (Gosse), Bosmina longirostris (O.F. Müller) and Chydorus sphaericus (O.F. Müller)), wzrostem całkowitej liczebnosci zooplanktonu z dominacja wrotków (tab. 3, ryc. 1, 2), zniszczeniami w strefie fitolitoralu i zmianami jakosciowymi i ilosciowymi w strukturze makrofitów (tab. 4).
Źródło:
Roczniki Akademii Rolniczej w Poznaniu. Botanika; 2003, 06
1508-9193
Pojawia się w:
Roczniki Akademii Rolniczej w Poznaniu. Botanika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Do toxic cyanobacteria blooms pose a threat to the Baltic ecosystem?
Autorzy:
Mazur-Marzec, H.
Plinski, M.
Powiązania:
https://bibliotekanauki.pl/articles/48101.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
eutrophication
Aphanizomenon flos-aquae
Baltic Sea
blue-green alga
brackish water
Nodularia spumigena
Cyanoprokaryota
harmful bloom
sea water
fresh water
Baltic ecosystem
nodularin
Opis:
Cyanobacteria, otherwise known as blue-green algae, are oxygenic, photosynthetic prokaryotes. They occur naturally in many fresh, marine and brackish waters worldwide and play an important role in global carbon and nitrogen cycles. In their long history, cyanobacteria have developed structures and mechanisms that enable them to survive and proliferate under different environmental conditions. In the Baltic Sea, the mass development of cyanobacteria is compounded by a high level of eutrophication. The dominant species in the Baltic, the filamentous Aphanizomenon flos-aquae and Nodularia spumigena, can fix dissolved atmospheric N2, as a result of which they can outcompete other phytoplankton organisms. Heterocystous, filamentous cyanobacteria also make a significant contribution to the internal nutrient loading in the Baltic. The blooms of N. spumigena are of particular concern, as this cyanobacterium produces nodularin (NOD), a hepatotoxic peptide. The concentration of the toxin in the sea is regulated mainly by dilution with uncontaminated water, photolysis, sorption to sediments and microbial degradation. The transfer of the toxin in the Baltic trophic chain through zooplankton, mussels, fish and birds has been reported, but biodilution rather than bioconcentration has been observed. Cyanobacterial blooms are thought to pose a serious threat to the ecosystem. Their harmful effects are related to the occurrence of a high biomass, oxygen depletion, a reduction in biodiversity, and the production of toxic metabolites.
Źródło:
Oceanologia; 2009, 51, 3; 293-319
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
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