What is "benthos"

Benthos \Ben"thos\ (b[e^]n"th[o^]s), n. [NL., fr. Gr. be`nqos depth of the sea.] The bottom of the sea, esp. of the deep oceans; hence (Bot. & Zo["o]l.), the fauna and flora of the sea bottom; -- opposed to plankton.

"life forms of the deep ocean and sea floor," 1891, coined by Haeckel from Greek benthos "depth of the sea," related to bathos "depth," bathys "deep," which is of unknown origin. Adjective benthic is attested from 1902.

n. The flora and fauna at the bottom of the ocean or other body of water.

1. n. a region including the bottom of the sea and the littoral zones [syn: benthic division, benthonic zone]

2. organisms (plants and animals) that live at or near the bottom of a sea

Benthos is the community of organisms that live on, in, or near the seabed, also known as the benthic zone. This community lives in or near marine 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 each 10 metres of water depth).

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, comes from the Greek noun "depth of the sea". Benthos is also used in freshwater biology to refer to organisms at the bottom of freshwater bodies of water, such as lakes, rivers, and streams.