Benthos

Part of a series related to
Benthic life
Benthos              Benthic zone Benthopelagic (coupling)        Seabed
By size macrobenthos meiobenthos microbenthos
By type zoobenthos phytobenthos
By location endobenthos epibenthos hyperbenthos
By habitat     Shallow: tide pool • bay mud • bivalve reef                    mangrove forest • coral reef                    seagrass meadow         Deep: seamount • cold seep                    hydrothermal vent
Communities Benthic fish Benthopelagic fish Bottom feeder Deep sea Deep sea communities Demersal fish Intertidal ecology Hydrothermal vent microbial communities
Related Epibenthic sled Van Veen grab sampler Bioirrigation Bioturbation Demersal zone Marine sediment
Marine life portal
v t e

Benthos (from Ancient Greek βένθος (bénthos) 'the depths [of the sea]'), also known as benthon, is the community of organisms that live on, in, or near the bottom of a sea, river, lake, or stream, also known as the benthic zone.^[1] This community lives in or near marine or freshwater sedimentary environments, from tidal pools along the foreshore, out to the continental shelf, and then down to the abyssal depths.

Many organisms adapted to deep-water pressure cannot survive in the upper parts of the water column. The pressure difference can be very significant (approximately one atmosphere for every 10 metres of water depth).^[2]

Because light is absorbed before it can reach deep ocean water, the energy source for deep benthic ecosystems is often organic matter from higher up in the water column that drifts down to the depths. This dead and decaying matter sustains the benthic food chain; most organisms in the benthic zone are scavengers or detritivores.

The term benthos, coined by Haeckel in 1891,^[3] comes from the Greek noun βένθος 'depth of the sea'.^[1][4] Benthos is used in freshwater biology to refer to organisms at the bottom of freshwater bodies of water, such as lakes, rivers, and streams.^[5] There is also a redundant synonym, Benton.^[6]