Benthos

The benthos ( benthic also, separately: the Benthont ) is the totality of all in the bottom zone of a water body, the benthic, living organisms. The word comes from the Greek benthos ( " deep sea ", " thicket "). The corresponding adjective is benthic.

The benthos includes both the fixed ( sessile ) organisms as well as the crawling, running or temporarily floating ( vagilen ) soil animals. The term was introduced in 1890 by Ernst Haeckel, to ensure that the soil -dwelling organisms in the sea distinguished from the open water, the pelagic zone, occurring ( plankton and nekton ). Today, the range encountered in the benthic biological communities ( communities ) of all types of waters, both inland waters and the various water depths, called benthos.

After the size of the living creatures, one distinguishes:

• Macrobenthos (> 1 mm)
• Meiobenthos (1 mm to 0.063 mm)
• Microbes Thos (below 0.063 mm)

After living space, a distinction:

• Epibenthic ( living on the substrate )
• Semi- Endobenthos (half alive in the substrate )
• Endobenthos ( in the substrate alive )
• Soil -related Nekton (floating Benthonten )

After the mobility it may be:

• Vagiles benthos ( mobile)
• Sessile benthos ( immobile or tacked )

Benthic creatures are of importance as food for fish and other larger animals of the free water, the nekton, but also as decomposers. Animal benthos ( zoobenthos ), such as crustaceans, flatfish and mussels also provide for the human diet is a valuable source of protein Vegetable benthos is because of photosynthesis from the light -dependent and therefore only in the photic zone of the littoral (depth up to 100-200 m) find. When plant benthos ( Phytobenthos ) Tang is commercially important. It attaches to flat coastal areas more than 60 m high forests form and is used in the production of various food and industrial products.

Typical benthic creatures are, for example,

• Macrobenthos: red algae ( Rhodoplantae ) - brown algae ( Phaeophyta ) - green algae ( Chlorophyta ) - crustaceans (Crustacea ) - Shells ( Bivalvia ) - snails ( Gastropoda ) - Fishes (Pisces ) - members worms ( Annelida )
• Meiobenthos: copepods - Water bears ( tardigrades ) - nematodes ( Nematoda ) - rotifers ( Rotifera ) - diatoms ( Bacillariophyta ) - Foraminifera ( Foraminifera )

As the oldest known benthic life form stromatolites apply.