Cyanobacteria can be found in almost every environment, from oceans to fresh water to bare rock to soil. They can occur as planktonic cells or form phototrophic biofilms in fresh water and marine environments. They occur in damp soil, or even on temporarily moistened rocks in deserts. Aquatic cyanobacteria are probably best known for the extensive and highly visible blooms that can form in both freshwater and the marine environment and can have the appearance of blue-green paint or scum. The association of toxicity with such blooms has frequently led to the closure of recreational waters when blooms are observed. Cyanobacteria are aquatic and photosynthetic, that is, they live in the water, and can manufacture their own food.
The following article appeared in the GPLA Newsletter of June 17, 2015 and was written by President Michael Riese.