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EARTH SCIENCE > BIOSPHERE > ECOLOGICAL DYNAMICS > COMMUNITY DYNAMICS > INDICATOR SPECIES

Definition:
Indicator species are defined as species which can provide information on
ecological changes and give early warning signals regarding ecosystem processes
in site-specific conditions due to their sensitive reactions to them. They can
also be called sentinel species, indicator organisms, biological indicators
("bioindicators"), biological markers, or environmental indicators. The latter
three expressions do not necessarily refer to species but also to other
environmental elements which can indicate environmental changes.


Reference:
Allaby, Michael, 1994, The Concise Oxford Dictionary of Ecology. See also the
Global Terrestrial Observing System (GTOS) Terrestrial Ecosystem Monitoring
Sites (TEMS) database: http://www.fao.org/gtos/tems/index.jsp