The neritic zone, also called coastal waters, the coastal ocean or the sublittoral zone, is the part of the ocean extending from the low tide mark to the edge of the continental shelf, with a relatively shallow depth extending to about 200 metres (110 fathoms or 667 feet). The neritic zone has generally well-oxygenated water, low water pressure, and relatively stable temperature and salinity levels.
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos. For example, the benthic invertebrate community, including crustaceans and polychaetes.