Toxic blooms of cyanobacteria in Lake Alexandrina, South Australia — Learning from history

1994 ◽  
Vol 45 (5) ◽  
pp. 731 ◽  
Author(s):  
GA Codd ◽  
DA Steffensen ◽  
MD Burch ◽  
PD Baker
Keyword(s):  
South Australia ◽  
Cyanobacterial Blooms ◽  
Nodularia Spumigena ◽  
Toxic Cyanobacteria ◽  
Toxic Blooms ◽  
Learning From History

Early accounts by European explorers and settlers of South Australia contain numerous references to scums or discoloured water that are consistent with cyanobacterial blooms. Documented reports refer back to at least 1853. The first detailed scientific account of toxic cyanobacteria appeared in 1878. In a perceptive and prescient paper in Nature, the Adelaide assayer and chemist George Francis reported on stock deaths at Milang on the shores of Lake Alexandrina in South Australia. Francis attributed the deaths to the ingestion and toxicity of scums of the cyanobacterium Nodularia spumigena. Reports of cyanobacterial blooms, scums and associated problems in Lake Alexandrina and in the River Murray between about 1851 and 1888 are discussed and comparisons are made with the reactions to blooms a century later.

scholarly journals Effects of toxic cyanobacteria on a plankton assemblage: community development during decay of Nodularia spumigena

2002 ◽  
Vol 232 ◽  
pp. 1-14 ◽  
Author(s):  
J Engström-Öst ◽  
M Koski ◽  
K Schmidt ◽  
M Viitasalo ◽  
SH Jónasdóttir ◽  
...  
Keyword(s):  
Community Development ◽  
Nodularia Spumigena ◽  
Toxic Cyanobacteria

Occurrence and Significance of Toxic Cyanobacteria in Southern Africa

1991 ◽  
Vol 23 (1-3) ◽  
pp. 175-180 ◽  
Author(s):  
W. E. Scott
Keyword(s):  
South Africa ◽  
Southern Africa ◽  
Single Species ◽  
Practical Significance ◽  
Toxic Species ◽  
Toxic Cyanobacteria ◽  
Cyanobacterial Species ◽  
Wide Range ◽  
Toxic Blooms ◽  
Different Parts

A comprehensive list is provided of more than forty cyanobacterial species and genera reported to have toxic properties. In South Africa the majority of animal poisonings since 1927 have been caused by a single species Microcystis aeruginosa. Although other toxic species also occur in southern Africa, to date they have been of little practical significance. The widespread distribution of M. aeruginosa throughout southern Africa indicates a tremendous potential for toxic blooms to develop with increasing eutrophication. Using HPLC techniques up to six different toxin variants have been quantified in natural blooms of M. aeruginosa collected in different parts of South Africa. The amounts and proportions of the different toxins in the different samples varied over a wide range. Several additional unidentified toxins were detected.

Grazing of the copepod Cyclops vicinus on toxic Microcystis aeruginosa: potential for controlling cyanobacterial blooms and transfer of toxins

2018 ◽  
Vol 47 (3) ◽  
pp. 296-302 ◽  
Author(s):  
Zakaria A. Mohamed ◽  
Asmaa A. Bakr ◽  
Hamed A. Ghramh
Keyword(s):  
Microcystis Aeruginosa ◽  
Grazing Rate ◽  
Cyanobacterial Blooms ◽  
Feeding Experiments ◽  
Cyclops Vicinus ◽  
Ankistrodesmus Falcatus ◽  
Toxic Cyanobacteria ◽  
Study Laboratory ◽  
Grazer Species

Abstract Grazing of zooplankton on phytoplankton may contribute to a reduction of harmful cyanobacteria in eutrophic waters. However, the feeding capacity and interaction between zooplankton and toxic cyanobacteria vary among grazer species. In this study, laboratory feeding experiments were designed to measure the grazing rate of the copepod Cyclops vicinus on Microcystis aeruginosa and the potential microcystin (MC) accumulation in the grazer. Copepods were fed a mixed diet of the edible green alga Ankistrodesmus falcatus and toxic M. aeruginosa for 10 days. The results showed that C. vicinus efficiently ingested toxic Microcystis cells with high grazing rates, varying during the feeding period (68.9–606.3 Microcystis cells animal-1 d-1) along with Microcystis cell density. Microcystis cells exhibited a remarkable induction in MC production under grazing conditions with concentrations 1.67–12.5 times higher than those in control cultures. Furthermore, C. vicinus was found to accumulate MCs in its body with concentrations increasing during the experiment (0.05–3.21 μg MC animal-1). Further in situ studies are needed to investigate the ability of Cyclops and other copepods to assimilate and detoxify MCs at environmentally relevant concentrations before deciding on the biocontrol of Microcystis blooms by copepods.

The effect of algal blooms on fish in their inshore nursery grounds in the Gulf of Gdańsk

2017 ◽  
Vol 98 (1) ◽  
pp. 97-104
Author(s):  
Anna J. Pawelec ◽  
Mariusz R. Sapota ◽  
Justyna Kobos
Keyword(s):  
Coastal Zone ◽  
Fish Species ◽  
Algal Blooms ◽  
Cyanobacterial Bloom ◽  
Biomass Accumulation ◽  
Fish Abundance ◽  
Gulf Of Gdańsk ◽  
Nodularia Spumigena ◽  
Toxic Blooms ◽  
Gulf Of Gdansk

Studies of cyanobacterial bloom dynamics show that the highest biomass accumulation of Nodularia spumigena is observed in the shallowest area of the Gulf of Gdańsk in summer. In the same region and time, the highest fish abundance is observed. Mostly young individuals of gobies, small sandeel, flounder, three-spine stickleback and young herring occur. In this work we compare how toxic blooms of cyanobacteria influence the number and structure of fish communities in a coastal zone. The results obtained in our study were rather unexpected. More fish species were caught and the biomass of fish was higher during a bloom than in a month following the sampling (no bloom).

scholarly journals Ultrasonic selectivity on depressing photosynthesis of cyanobacteria and green algae probed by chlorophyll-a fluorescence transient

2017 ◽  
Vol 76 (8) ◽  
pp. 2085-2094 ◽  
Author(s):  
Zhipeng Duan ◽  
Xiao Tan ◽  
Niegui Li
Keyword(s):  
Chlorophyll A ◽  
Green Algae ◽  
Electron Acceptor ◽  
Cell Concentration ◽  
Electron Flow ◽  
Chlorella Pyrenoidosa ◽  
Cyanobacterial Blooms ◽  
Cell Structures ◽  
Toxic Cyanobacteria ◽  
New Strategy

Ultrasound can inhibit cyanobacterial growth through rupturing cells, but this pathway frequently has the risk to release intercellular toxin (e.g., microcystin). Depressing photosynthesis without cell disruption may provide a new strategy to control cyanobacterial blooms using ultrasound, especially Microcystis blooms. In this work, Microcystis aeruginosa (toxic cyanobacteria) and Chlorella pyrenoidosa (typical green algae) were chosen as model microalgae to verify this hypothesis. Results showed that ultrasound has the ability to inhibit cyanobacterial photosynthesis significantly and selectively. Specifically, sonication damaged QA, a tightly bound one-electron acceptor, and blocked electron flow at QB, a two-electron acceptor, in the photosystem II (PSII) of M. aeruginosa when it was exposed for 60 s (35 kHz, 0.043 W/cm3). Moreover, 44.8% of the reaction centers (RCs) in the PSII of M. aeruginosa were transferred into inactive ones (RCsis), and the cell concentration decreased by 32.5% after sonication for 300 s. By contrast, only 7.9% of RCsi occurred in C. pyrenoidosa, and cell concentration and chlorophyll-a content reduced by 18.7% and 9.3%, respectively. Differences in both species (i.e., cell structures) might be responsible for the varying levels to sonication. This research suggests that cyanobacteria, especially Microcystis, could be controlled by ultrasound via damaging their PSIIs.

scholarly journals Occurrence of toxin-producing cyanobacteria blooms in a Brazilian semiarid reservoir

2006 ◽  
Vol 66 (1b) ◽  
pp. 211-219 ◽  
Author(s):  
I. A. S. Costa ◽  
S. M. F. O Azevedo ◽  
P. A. C. Senna ◽  
R. R. Bernardo ◽  
S. M. Costa ◽  
...  
Keyword(s):  
Transition Period ◽  
Local Population ◽  
Fish Muscle ◽  
Control Measures ◽  
Northeastern Brazil ◽  
Cyanobacterial Blooms ◽  
Cylindrospermopsis Raciborskii ◽  
Semiarid Region ◽  
Dry Seasons ◽  
Toxic Blooms

We report the occurrence of cyanobacterial blooms and the presence of cyanotoxins in water samples from the Armando Ribeiro Gonçalves reservoir (06° 08’ S and 37° 07’ W), located in the state of Rio Grande do Norte, in the semiarid region of northeastern Brazil. The cyanobacterial species were identified and quantified during the rainy and dry seasons in the year 2000. Cyanotoxins such as microcystins, saxitoxins and cylindrospermopsins were analyzed and quantified using HPLC and ELISA methods. The mixed toxic blooms of Cylindrospermopsis raciborskii, Microcystis spp (M. panniformis, M. protocystis, M. novacekii) and Aphanizomenon spp (Aphanizomenon gracile, A. cf. manguinii, A. cf. issastschenkoi) were persistent and represented 90-100% of the total phytoplankton species. Toxic cyanobacterial blooms from the Armando Ribeiro Gonçalves reservoir were analyzed and found to have three phases in relation to the annual cycle. During the rainy season, an intense toxic bloom of Cylindrospermopsis raciborskii was recorded along with saxitoxins (3.14 µg.L-1). During the transition period, between the rainy and dry seasons, different species of Microscytis occurred and microcystin as high as 8.8 µg.L-1 was recorded. In the dry season, co-dominance of Cylindrospermopsis raciborskii, Microcystis spp and Aphanizomenon spp occurred and the concentrations of saxitoxin remained very low. Our results indicate the presence of microcystins (8.8 µg.L-1) and saxitoxins (3.14 µg.L-1) into the crude water, with increasing concentrations from the second fortnight of April to late May 2000. The occurrence of toxic blooms in this reservoir points to a permanent risk of cyanotoxins in supply waters, indicating the need for the implementation of bloom control measures to improve the water quality. Exposure of the local population to cyanotoxins through their potential accumulation in fish muscle must also be considered.

scholarly journals Temporal and spatial variability of cyanobacterial toxins microcystins in three interconnected freshwater reservoirs

2010 ◽  
Vol 75 (9) ◽  
pp. 1303-1312 ◽  
Author(s):  
Luděk Bláha ◽  
Lucie Bláhová ◽  
Jiří Kohoutek ◽  
Ondřej Adamovský ◽  
Pavel Babica ◽  
...  
Keyword(s):  
Dry Weight ◽  
Cyanobacterial Blooms ◽  
World Health ◽  
Cyanobacterial Toxins ◽  
Toxic Cyanobacteria ◽  
Guideline Value ◽  
High Concentrations ◽  
Health Organization ◽  
Reported Data ◽  
Natural Dynamics

In spite of substantial research on health and the ecological risks associated with cyanobacterial toxins in the past decades, the understanding of the natural dynamics and variability of toxic cyanobacterial blooms is still limited. Herein, the results of long term monitoring 1998-1999 / 2001-2008 of three reservoirs (V?r, Brno and Nov? Ml?ny), where toxic blooms develop annually, are reported. These three reservoirs provide a unique model because they are interconnected by the Svratka River, which allows possible transfer of phytoplankton as well as toxins from one reservoir to another. The frequency of the occurrence and dominance of the major cyanobacterial taxa Microcystis aeruginosa did not change during the investigated period but substantial variability was observed in the composition of other phytoplankton. Although absolute concentrations of the studied toxins (microcystins) differed among the reservoirs, there were apparent parallel trends. For example, during certain years, the microcystin concentrations were systematically elevated in all three studied reservoirs. Furthermore, the concentration profiles in the three sites were also correlated (parallel trends) within individual seasons based on monthly sampling. Microcystin-LR, a variant for which the World Health Organization has recommended a guideline value, formed only about 30-50% of the total microcystins. This is of importance, especially in the V?r reservoir that serves as a drinking water supply. Maxima in the cell-bound microcystins (intracellular; expressed per dry weight biomass) generally preceded the maxima of total microcystins (expressed per volume of water sample). Overall, the maximum concentration in the biomass (all three reservoirs, period 1993-2005) was 6.1 mg g-1 dry weight and the median values were in the range 0.065-2.3 mg g-1 dry weight. These are generally high concentrations in comparison with both Czech Republic and worldwide reported data. The present data revealed substantial variability of both toxic cyanobacteria and their peptide toxins that should be reflected by detailed monitoring programs.

scholarly journals Degradation of [Dha7]MC-LR by a Microcystin Degrading Bacterium Isolated from Lake Rotoiti, New Zealand

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Theerasak Somdee ◽  
Michelle Thunders ◽  
John Ruck ◽  
Isabelle Lys ◽  
Margaret Allison ◽  
...  
Keyword(s):  
New Zealand ◽  
Cyanobacterial Blooms ◽  
Recreational Water ◽  
16S Rrna Sequence ◽  
Degrading Bacterium ◽  
Naturally Occurring ◽  
16S Rrna Sequence Analysis ◽  
Toxic Blooms ◽  
First Time ◽  
By Products

For the first time a microcystin-degrading bacterium (NV-3 isolate) has been isolated and characterized from a NZ lake. Cyanobacterial blooms in New Zealand (NZ) waters contain microcystin (MC) hepatotoxins at concentrations which are a risk to animal and human health. Degradation of MCs by naturally occurring bacteria is an attractive bioremediation option for removing MCs from drinking and recreational water sources. The NV-3 isolate was identified by 16S rRNA sequence analysis and found to have 100% nucleotide sequence homology with the Sphingomonas MC-degrading bacterial strain MD-1 from Japan. The NV-3 isolate (concentration of 1.0×108 CFU/mL) at 30°C degraded a mixture of [Dha7]MC-LR and MC-LR (concentration 25 μg/mL) at a maximum rate of 8.33 μg/mL/day. The intermediate by-products of [Dha7]MC-LR degradation were detected and similar to MC-LR degradation by-products. The presence of three genes (mlrA, mlrB, and mlrC), that encode three enzymes involved in the degradation of MC-LR, were identified in the NV-3 isolate. This study confirmed that degradation of [Dha7]MC-LR by the Sphingomonas isolate NV-3 occurred by a similar mechanism previously described for MC-LR by Sphingomonas strain MJ-PV (ACM-3962). This has important implications for potential bioremediation of toxic blooms containing a variety of MCs in NZ waters.

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