The profound effect of harmful cyanobacterial blooms: From food-web and management perspectives

• Published in: The Science of the total environment Vol. 609; pp. 1443 - 1450
• Main Authors: Šulčius, Sigitas, Montvydienė, Danguolė, Mazur-Marzec, Hanna, Kasperovičienė, Jūratė, Rulevičius, Rokas, Cibulskaitė, Živilė
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 31-12-2017
• Subjects: Aphanizomenon flos-aquae; Baltic Sea; Curonian Lagoon; Cyanotoxins; Recreational waters; Recreational waters; Curonian Lagoon; Aphanizomenon flos-aquae; Baltic Sea; Cyanotoxins
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2017.07.253

Sustainable and effective water management plans must have a reliable risk assessment strategies for harmful cyanobacterial blooms (HABs) that would enable timely decisions to be made, thus avoiding the trespassing of ecological thresholds, leading to the collapse of ecosystem structure and function. Such strategies are usually based on cyanobacterial biomass and/or on the monitoring of known toxins, which may, however, in many cases, under- or over-represent the actual toxicity of the HAB. Therefore, in this study, by the application of growth-inhibition assays using different bacteria, algae, zooplankton and fish species, we assessed the toxicological potential of two cyanobacterial blooms that differed in total cyanobacterial biomass, species composition and cyanopeptide profiles. We demonstrated that neither cyanobacterial community composition nor its relative abundance, nor indeed concentrations of known toxins reflected the potential risk of HAB based on growth-inhibition assays. We discuss our findings in the context of food-web dynamics and ecosystem management, and suggest that toxicological tests should constitute a key element in the routine monitoring of water bodies so as to prevent under-/over-estimation of potential HAB risk for both ecosystem and public health.
[Display omitted]
•The ‘bathing water profile’ does not reflect the toxicological potential of HABs.•The growth-inhibiting potential of the HAB varies between different HABs.•The growth-inhibiting potential of the HAB varies between different species and strains of organism.•Bioassays should become standard routine procedure in aquatic monitoring programs.