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Biomonitoring Jeziora Otmuchowskiego (południowo-zachodnia Polska) z wykorzystaniem sinic

Rajfur M., Rambau W., Jerz D., Kłos A.

Proceedings of ECOpole

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2012

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Vol. 6, No. 2

593--600

PL

Celem przeprowadzonych badań była ocena możliwości wykorzystania sinic w biomonitoringu wód. Do badań wykorzystano cyanobacterie zebrane w strefie litoralnej Jeziora Otmuchowskiego (południowo-zachodnia Polska). W biocie metodą absorpcyjnej spektrometrii atomowej (AAS) oznaczono stężenia: Mn, Fe, Cu, Zn, Cd i Pb. Na podstawie przeprowadzonych badań dokonano wstępnej oceny zanieczyszczenia wód jeziora. Wartości stężeń metali ciężkich w sinicach porównano ze stężeniami tych metali w próbkach wody. Wyznaczone współczynniki biokoncentracji (BCF) wskazują na dobre właściwości akumulacyjne badanych cyanobacterii.

EN

The objective of our studies was to evaluate the applicability of selected cyanobacteria in water biomonitoring. The cyanobacteria collected in the littoral zone of the Otmuchowskie Lake (south-western Poland) were used in the studies. The concentrations of Mn, Fe, Cu, Zn, Cd and Pb were determined in the biota by means of the Atomic Absorption Spectrometry (AAS). Pollution of the lake water was preliminary assessed. Concentrations of the heavy metals in cyanobacteria were compared with these in water samples. The value of bioconcentration factor (BCF) shows good accumulation of metals in cyanobacteria.

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Winter versus summer blooming of phytoplankton in a shallow lake: effect of hypertrophic conditions

Toporowska M., Pawlik-Skowrońska B., Krupa D., Kornijów R.

Polish Journal of Ecology

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2010

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Vol. 58, nr 1

3-12

EN

The comparison of species richness, abundance and diversity of phytoplankton blooms, which developed both in winter and summer seasons as an effect of lake hypertrophy, was the aim of this study. In the ice-covered lake (0.30 mg PO[4]-P L[^-1], 1.35 mg NH[4]-N L[^-1]; TSI[SD] = 64; TSI[chl] = 93), the algal bloom, responsible for high concentration of dissolved oxygen in water, consisted mainly of the centric diatom Stephanodiscus minutulus (3.9 x 10[^7] ind. L[^-1]) accompanied by Limnothrix redekei (Cyanobacteria), Koliella longiseta (Chlorophyceae), > 1.1 x 10[^6] ind. L[^-1] each, as well as Mallomonas sp. (Chrysophyceae) and Monoraphidium komarkovae (Chlorophyceae), >5.0 x 10[^5] ind. L[^-1] each. The toxic cyanobacterium Planktothrix agardhii of extremely long trichomes (up to 0.93 mm) and potentially toxic dinoflagellate Peridinium aciculiferum f. inerme occurred also in high numbers (1.9 x 10[^5] ind. L[^-1] and 7.7 x 10[^4] ind. L[^-1], respectively). In summer (0.05 mg PO[4]-P L[^-1]; 0.42 mg NH[4]-N L[^-1]; TSI[SD] = 78; TSI[chl] = 102), the phytoplankton bloom consisted of P. agardhii (average total abundance 49.4 x 10[^6] ind. L[^-1]) and ten other taxa of Cyanobacteria, Bacillariophyceae, Chlorophyceae and Cryptophyceae (average total abundance 17.9 x 10[^6] ind. L[^-1]). The total phytoplankton abundance was 1.5 times higher in summer than in winter and the total biomass of the most abundant species was approximately 4 times higher in warm (139.8 mg L[^-1]) than in cold season (32.5 mg L[^-1]). The values of the Shannon-Weaver diversity index were very low, however, over 2 times higher in summer (0.60) than in winter (0.31). The obtained results revealed that in the hypertrophic lake the very high nutrient concentrations (especially NH[4]-N and PO[4]-P), found both in winter and summer, were responsible for year-long mass development of phytoplankton. The winter phytoplankton was composed mainly of very small centric diatoms, whereas summer blooms were created by filamentous cyanobacteria (mainly Oscillatoriales; 98%).

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Insecticidal activity - a new bioactive property of the cyanobacterium Fischerella

Becher Paul G., Juttner Friedrich

Polish Journal of Ecology

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2006

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Vol. 54, nr 4

653-662

EN

Cyanobacterial biofilms serve as food and as shelter for benthic invertebrates, such as juvenile insects. Chironomids are often the most frequently found and abundant insect larvae in freshwater ecosystems. As a consequence of high grazing pressure, effective defence mechanisms can be expected in biofilm-forming organisms. The presence of chemical defence was studied in detail in 12 axenic and monoxenic cyanobacterial species. Flakes of cyanobacterial biofilms were offered to Chironomus riparius (Meigen) over a period of 8 days. Mortality and body-length of the surviving animals were used as indicators for the toxicity of the cyanobacteria and their suitability as food. Toxicity and inhibition of larval growth were found for several cyanobacteria tested. Fischerella sp. (ATCC 43239) was the most active and caused 100% mortality in Chironomus larvae within 24 h. Mortality was also high (87%) for larvae fed with Aphanothece sp. Moderate toxicity (40-60% mortality) was found for Calothrix sp. (PCC 7507), C. braunii Bornet et Flahault, C. thermalis (Schwabe) Hansgirg and a cyanobacterium of the LPP group designated JU 5. Mortality of 7-33% was observed for Calothrix parietina (Nageli) Thuret, Oscillatoria brevis (Kutzing) Gomont, Cylindrospermum sp., Nostoc sp., Calothrix anomala Mitra and a cyanobacterium of the LPP group designated 5 KB. Differences depending on the cyanobacterial food offered were also seen in the lengths of surviving larvae. Fischerella sp. (ATCC 43239) was studied in more detail to chemically characterize the observed insecticidal activity. The insecticidal activity could be extracted with 60% aq. methanol from the fresh biomass and caused 100% mortality in Chironomus. A literature survey was performed on the bioactive compounds so far isolated and characterized from Fischerella and related Stigonematales. It is noticeable that no insecticidal activity has been shown for any of these compounds yet. The newly found insecticidal property of Fischerella may lead to the identification of bioactive compounds which may be important as a chemical defence against insect grazers.