Organically shaped flow
![](https://upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Tollense-bei-Brook-26-VIII-2007-27.jpg/220px-Tollense-bei-Brook-26-VIII-2007-27.jpg)
The organically shaped river (type 12) is a type of flowing water defined by the Federal / State Working Group on Water (LAWA) . It belongs to the ecoregion-independent types , so it can occur both in the north German lowlands and in the Alpine foothills .
Water structure
An organically shaped river usually consists of a meandering, slowly flowing main course with many side channels, with no clear demarcation from the floodplain . The river bed is hardly cut. Like the surrounding floodplain, it usually consists of organic substrates such as peat , fallen leaves or mud. Sometimes the bottom of the river consists partly of sand or other mineral substrates, but is surrounded by an organic fen .
The water often has a brownish color due to the bogs.
Flora and fauna
Both slow-flowing and still-water species occur in this type of river. In the case of invertebrates , these are, for example, mayfly larvae that colonize deadwood or aquatic plants , various caddis-fly larvae and cephalopods ; in the case of fish, chub , bleak and some perch, among others .
Many large spawning herbs such as the common hedgehog or the specular pondweed occur in aquatic plants . The river areas within the young moraines are also densely populated with reed beds , floating leaf plants and spawning herbs . However, there is no plankton .
Examples
swell
- Profile of the river type 12 on wasserblick.net (PDF; 230 kB)