Published by Australian Academy of Science
Glossary | Toxic algal blooms – a sign of rivers under stress

bloom. A rapid temporary increase in the population of aquatic photosynthetic microorganisms (eg, phytoplankton or cyanobacteria) to the extent that the water becomes discoloured and, if the microorganisms are toxin-producers, unfit for drinking.

ecosystem. A term used to encompass all the organisms in a community together with the associated physical environmental factors with which they interact (eg, a rockpool ecosystem, a forest ecosystem).

eutrophication. An increase in the nutrient content of a body of water, occurring either naturally or as a result of human activities. It often leads to a rapid increase (bloom) in growth of algae. The death and eventual decomposition of the algae results in a lowering of the oxygen level until the water cannot support organisms that require oxygen.

photosynthesis. The biochemical process in which green plants (and some microorganisms) use energy from light to synthesise carbohydrates from carbon dioxide and water.