Psammon

The term Psammon (sometimes also Psammion ) is derived from the Greek word ψάμμος psammos "sand" and describes the totality of the organisms living on and in the sandy substrate of the waters . The psammon is therefore a part of the benthos , that is the totality of the organisms occurring on and in the bottom of the water.

Studies of the microbiology of sandy river banks have been around since 1926, when D. Sassuchin published the results of his microscopic studies on the Oka in Russia. In 1927 he proposed the term Psammon "analogous to the term Edaphon ". The characteristic of the psammon the rivers organisms include the groups of algae , rotifers , belly-haired animals , flatworms , nematodes , tardigrades and oligochaetes on.

Later the term psammon was also established for the sandy coasts of the seas . Similar to the sandbanks of the rivers, the impact of the waves in the marine sublittoral area results in a highly unstable environmental situation. It is difficult for plants to take root or to attach themselves in a sandy environment. Therefore, there are few organisms that graze plants. The inhabitants of the Psammon are largely dependent on the utilization of detritus .

The composition of the Psammon fauna is determined by the grain size of the sand . Most of the animals live here in the spaces between the grains of sand, the "sand gap system" or mesopsammon . They are usually between 0.3 and 1 mm in size and thus belong to the meiofauna .

The Polish biologist Wiszniewski proposed a tripartite division of the Psammon habitat:

• Eupsammon - the part of the sandy shore or sandbanks that is above the water level and is little affected by the waves
• Hygropsammon - the part of the sand bank that lies in the area of ​​the waves and remains completely soaked through the hygroscopicity of the water
• Hydropsammon - the part that is always completely covered by water

According to the spatial connection with the soil, the psammon is also divided into:

• Endoposammon - the organisms that live in the sandy soil,
• Epipsammon - the organisms that live on the sandy soil.

See also

• Marine biology
• Freshwater biology

Web links

• Psammon. In: Spectrum Lexicon of Biology.

Individual evidence

1. ↑ D. Sassuchin, M. Kabanov and K. Neiswestova: About the microscopic flora and fauna of the sandy area of ​​the Okaufer near Murom. Soot. Hydro. Magazine 6 (3/5), Saratov, 1927, pp. 135-173
2. ↑ Ulrich Sommer : Biological Oceanography . Springer, 2016, 8 marine communities III: The benthos of the sediments, doi : 10.1007 / 978-3-662-50407-9 .