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Dynamic of Filamentous Cyanobacteria in the Dam Ain Zada (North of Algeria)

Samia Charifi, Tarek Merad, Zohra Guellati Fatma, Hassen Touati, Mourad Bensouilah

Journal of Ecological Engineering

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2019

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Vol. 20, nr 5

97--110

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.

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A comparison of epilimnetic versus metalimnetic phytoplankton assemblages in two mesotrophic lakes

Napiórkowska-Krzebietke A., Hutorowicz A.

Oceanological and Hydrobiological Studies

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2013

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Vol. 42, No. 1

89-98

EN

The epilimnetic and metalimnetic phytoplankton assemblages were compared in two mesotrophic lakes (L. Hańcza and L. Dejguny, northeastern Poland) and a “metalimnetic niche” is described. Phytoplankton analysis conducted during July and August 2006, 2007, and 2008 indicated that the total phytoplankton biomass in both lakes was relatively small (from 0.6 to 5.2 mg dm-3), with maximum values mainly occurring in the metalimnion. The lowest number of species and diversity indices values were usually observed in the metalimnetic layers. Lake Hańcza was dominated by diatoms (e.g. Cyclotella spp.) whereas Lake Dejguny was mainly dominated by cyanoprokaryotes (e.g. Planktothrix agardhii), with a distinct predominance of diatoms (e.g. Tabellaria flocculosa) in 2007. The common features of the phytoplankton assemblages in both lakes were a tolerance to nutrient and light deficiencies. A cluster analysis of the taxonomic patterns indicated large dissimilarities between the lakes. The phytoplankton assemblages developed under the influence of seasonal conditions, especially in Lake Hańcza. The distinction between metalimnetic and epilimnetic phytoplankton assemblages only appeared in Lake Dejguny.

3

The effect of cyanobacterial blooms in the Siemianówka Dam Reservoir on the phytoplankton structure in the Narew River

Grabowska M., Mazur-Marzec H.

Oceanological and Hydrobiological Studies

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2011

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Vol. 40, No.1

19-26

EN

The effect of cyanobacterial blooms on the phytoplankton structure in the lowland Narew River (north-eastern Poland) was examined. The studies were carried out at stations situated at different distances from the eutrophic Siemianówka Dam Reservoir. In 2008, the investigated lowland reservoir and the outflowing river were characterized by the dominance of toxic cyanobacteria (from July to October). At a station situated 130 km below the dam, species composition in the river was very similar to that in the shallow reservoir. Planktothrix agardhii was the main and permanent dominant, both in limnoplankton and potamoplankton. The current study indicates that the eutrophic Siemianówka Dam Reservoir is the main and rich source of phytoplankton for the outflowing Narew River. Cyanobacteria were dominant in the river phytoplankton at all sampling stations, but their share in phytoplankton biomass gradually decreased with the distance from the dam. Chemical analysis revealed the presence of microcystins (MCs) in water samples collected from June to October. The toxins, mainly demethylated MC analogues, were detected at a long distance down the river, even 100 km from the dam. Maximum concentration of MCs (14.3 μg l-1) was measured on 13 October, 9.1 km below the dam.

4

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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Replacement of chroococcales and nostocales by oscillatoriales caused a significant increase in microcystin concentrations in a dam reservoir

Grabowska M., Pawlik-Skowrońska B.

Oceanological and Hydrobiological Studies

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2008

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Vol. 37, No.4

23-33

EN

A two-year study on cyanobacterial development and the dynamics of intracellular microcystins was carried out in a shallow dam reservoir. Potentially toxic cyanobacteria (Microcystis wesenbergii, M. aeruginosa, Woronichinia naegeliana, Anabaena spp., Planktothrix agardhii) were observed to be the main component (70-94% total biomass) of the phytoplankton community, in which species composition was unstable and was very different between the 2005 and 2006 summer seasons. Generally, total phytoplankton, cyanobacterial biomass and total microcystin (MC) concentrations in the reservoir were much higher in 2006 than in 2005. The highest MC concentration (173.8 žg MC-LR equivalent dm-3) was seen in 2006 during P. agardhii (Oscillatoriales) domination (max. fresh biomass 50.3 mg dm-3; above 91% of phytoplankton biomass). Positive correlations between microcystin concentrations and cyanobacterial biomass suggest that populations of Nostocales and Oscillatoriales in 2005 and Oscillatoriales (P. agardhii) in 2006 may have been the main producers of MCs in the reservoir. The strong increase in P. agardhii biomass concomitant with a decrease in the total biomass of Chroococcales and Nostocales was responsible for the increase in MC concentration in the Siemianówka dam reservoir.

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Seasonal changes of phytoplankton dominated by Cyanoprocaryota in Lake Laskownickie

Messyasz B.

Oceanological Studies

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1998

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Vol. 27, No. 1

33-37

EN

The studies on the changes in phytoplankton composition against a background of selected physico-chemical factors of water in Lake Laskownickie (near Wagrowiec, Poland) were carried out in spring-summer seasons of 1993 to 1995. The changes in the qualitative and quantitative composition of phytoplankton and dynamics of Cyanoprocaryota populations in the vegetation season were connected with high concentrations of the phytoplankton biomass (10-70 mg dm^3), chlorophyll a (18.7-195.7mug dm^3) and biogens (Tot. P 0.040-1.100 mg P dm^3; Tot. N 3.77-12.00 mg dm^3). The blooms of Cyanoprocaryota occured in this reservoir each year. They were dominated by species such as: Plankto-thrix agardhii (Gom.) Anagnostidis et Komarek, Limnothrix redekei (Van Goor) Meffert, Aphanizomenon issatschenkoi (Vsac) Prosk-Lavr, Pseudoanabaena limnetica (Lemm.) Kom.. During blooms, the changes of the composition of companion taxa were observed.