where do benthic organisms live in aquatic ecosystems
Benthic zone 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, e.g. the benthic invertebrate community, including crustaceans and polychaetes.[1] The organisms generally live in close relationship with the substrate bottom and many are permanently attached to the bottom. The superficial layer of the soil lining the given body of water, the benthic boundary layer, is an integral part of the benthic zone, as it greatly influences the biological activity that takes place there. Examples of contact soil layers include sand bottoms, rocky outcrops, coral, and bay mud.
Ice The result of this process is that ice (in its most common form) floats on liquid water, which is an important feature in Earth's biosphere. It has been argued that without this property, natural bodies of water would freeze, in some cases permanently, from the bottom up,[10] resulting in a loss of bottom-dependent animal and plant life in fresh and sea water. Sufficiently thin ice sheets allow light to pass through while protecting the underside from short-term weather extremes such as wind chill. This creates a sheltered environment for bacterial and algal colonies. When sea water freezes, the ice is riddled with brine-filled channels which sustain sympagic organisms such as bacteria, algae, copepods and annelids, which in turn provide food for animals such as krill and specialised fish like the bald notothen, fed upon in turn by larger animals such as emperor penguins and minke whales.[11]