The magnitude of phytoplankton blooms has increased significantly in many areas of the world during the past 11 years, as shown in data from ocean color sensors on board satellites. These areas with increased blooms are likely to be environmentally stressed and undergoing undesirable environmental changes such as a higher frequency of harmful algal blooms and oxygen depletion in bottom layers of oceans, estuaries, and lakes. These changes can disrupt traditional fisheries and recreational use in many coastal areas.
An algal bloom is a rapid increase in the concentration of phytoplankton algae that occurs when conditions turn favorable for algal growth. A typical example of a bloom is the phytoplankton spring bloom. Algal blooms are natural phenomena that remove dissolved carbon and nutrients. In addition, they produce new biomass that supports higher trophic levels including fish and fisheries. However, the blooms also lead to excessive turbidity, oxygen depletion in the bottom layers, and the possible death of fish, benthic animals, and bottom vegetation.