Definition of Benthic

The benthic zone is an ecological region that is present at the lowest level of water bodies like lakes, oceans, and streams. They also include the subsurface layers and sedimentary surfaces. The organisms that reside in this region are called benthos. The example of benthos includes microorganisms like fungi and bacteria, invertebrates like polychaetes and crustaceans, etc.


A number of these organisms are permanently attached to the bottom surface. The benthic zone starts from the littoral zone and extends below along the surface of the continental shelf. Light is unable to reach the benthic zone, so the source of energy for the organisms for this region is dead and decaying matter.

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