Bloom-forming cyanobacteria

In this way, the near-linear chlorophyll-phosphorus relationship in lakes depends upon the outcome of a large number of interactive processes occurring in each one of the component systems in the model. One of the most intriguing aspects of those components is that the chlorophyll models do not need to take account of the species composition of the phytoplankton in which chlorophyll is a constituent. The development of blooms of potentially toxic cyanobacteria is associated with eutrophication and phosphorus concentration, yet it is not apparent that the yield of cyanobacterial biomass requires any more mass-specific contribution from phosphorus. The explanation for this paradox is not well understood, but it is extremely important to understand that it is a matter of dynamics. The bloom-forming cyanobacteria are among the slowest-growing and most light-sensitive members of the phytoplankton. ... 

Vahtera, E., Laanemets, J., Pavelson, J., Huttunen, M., Kononen, K., 2005. Effect of upwelling on the pelagic environment and bloom-forming cyanobacteria in the western Gulf of Finland, Baltic Sea. Journal of Marine Systems, 58, 67-82. 

Total biovolume, % of bloom-forming cyanobacteria, Algae Group Index (InGa Agenda Catalana de TAigua,... 

Briand, E., Gugger, M., Frangois, J.C., Bernard, C., Humbert, J.F., Quiblier, C. (2008). Temporal variations in the dynamics of potentially microcystin-producing strains in a bloom-forming Planktothrix agardhii (cyanobacteria) population. Appl. Environ. Microbiol. 74 3839 8. 

One main characteristic of bloom forming freshwater cyanobacteria is their ability to regulate buoyancy with the aid of gas vesicles and thus to avoid light limitation in turbid waters. This provides a clear competitive advantage over other phytoplankton that may sediment when the water column is stable during periods of thermal stratification. Buoyancy due to gas vesicles frequently induces the formation of surface blooms, so-called scums, thus causing a high variability in spatial distribution of cyanobacteria. ... 

Toxic cyanobacteria occur naturally in eutrophied waters, and toxin production is a common feature among bloom forming genera and species. A sustained control or reduction of cyanotoxin concentration can therefore only be reached by reducing the potential of a water body to support cyanobacterial blooms. Nutrient load reduction and catchment management are therefore the most appropriate long-term measures to diminish the health risks of cyanobacterial toxins. 

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