Benthic zone

Ecological region at the lowest level of a body of water

The benthic zone, from Ancient Greek βένθος (bénthos) 'the depths of the ocean', is the ecological region at the lowest level of a body of water, such as a stream, river, lake, or ocean, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos or, more informally, bottom dwellers. They include microorganisms such as bacteria and fungi, as well as larger invertebrates such as crustaceans and polychaetes.

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