Blue-Green Algae in Surface Water: Problems and Opportunities

Abstract

Purpose of ReviewCyanobacteria, commonly known as blue-green algae, are often seen as a problem. Their accumulation (bloom) in surface water can cause toxicity and aesthetic concerns. Efforts have been made in preventing and managing cyanobacterial blooms. By contrast, purposeful cultivation of cyanobacteria can create great opportunities in food, chemical and biofuel applications. This review summarises the current stage of research and the socio-economic impacts associated with both the problems and opportunities induced from the presence of cyanobacteria in surface water. Recent FindingsInsightful knowledge of factors that trigger cyanobacterial blooms has allowed for the development of prevention and control strategies. Advanced technologies are utilised to detect, quantify and treat cyanobacterial biomass and cyanotoxins in a timely manner. Additionally, understanding of cyanobacterial biochemical properties enables their applications in food and health industry, agriculture and biofuel production. Researchers have been able to genetically modify several cyanobacterial strains to obtain a direct pathway for ethanol and hydrogen production.

Comparison of Different Anode Materials to Remove Microcystis aeruginosa Cells Using Electro-Coagulation–Flotation Process at Low Current Inputs

“…A quite similar result was reported by Gao et al [15]. They demonstrated that 25 min treatment was adequate for 100% M. aeruginosa removal at 5 mA/cm 2…”

“…As a result of rapid oxygen consumption, hypoxic conditions develop, resulting in plant and animal die-off in water bodies [1]. These blooms are a threat to the drinking water supply owing to their potential toxicity and the release of taste and odor compounds such as geosmin and 2-methyl-isoborneol (2-MIB) [2,3]. Generally, cyanobacteria release a large amount of soluble algogenic organic matter (AOM) to the water such as extracellular organic matter (EOM), which is expelled to the water by living algal cells as a product of their metabolic activities, and intracellular organic matter (IOM), which is secreted upon the rupture of cells caused by endogenous or exogenous factors [4][5][6].…”

Sporadic Diurnal Fluctuations of Cyanobacterial Populations in Oligotrophic Temperate Systems Can Prevent Accurate Characterization of Change and Risk in Aquatic Systems

“…Cyanobacteria are recognized as a threat to surface water quality because they can form dense blooms and produce secondary metabolites including taste and odor compounds (e.g., geosmin, 2-methyl isoborneol) and potent cyanotoxins (Harke et al, 2016;Huisman et al, 2018;Paerl, 2014;Vu et al, 2020). As a result of anthropogenic activities, cyanobacterial bloom frequency and intensity have been increasing (Huisman et al, 2018); climate change-exacerbated landscape disturbances (e.g., wildfires) further promote their proliferation (Emelko et al, 2016;Silins et al, 2014).…”

Non-Nitrogen-Fixers or Nitrogen-Fixers? Factors Distinguishing the Dominance of Chroococcal and Diazotrophic Cyanobacterial Species

“…In addition, many cyanobacterial species produce toxins and release them into the water, making them unsuitable for drinking and recreational use. Blooms cause economic damage by affecting tourism, agriculture [ 8 ], and aquaculture industries [ 9 ]. However, cyanobacterial blooms are not an ecological endpoint, but rather an intermediary [ 10 ]; they cause changes in biodiversity and functionality of other communities [ 11 , 12 ], but also respond to changes in aquatic ecosystems.…”