A softwood is a bordering directly to a river bank, mainly from soft woods formed Auwald which is often flooded. There the plants are regularly exposed to mechanical loads from currents and ice . In Central Europe , this type of forest is mainly made up of various willows (e.g. white willow , broken willow ), black alder and black poplar . In the plant-sociological system, the softwood alluvial forests form the Salicion albae association , named after the white willow.
The natural proportion of poplars in the softwood alluvial forest is partly controversial. The proportion of black poplars was probably higher in southern and eastern Germany. Possibly the species was completely absent in northwest Germany. Due to the reshaping by humans, this question can hardly be answered today. Afforestation with poplar species is now widespread in alluvial forests and takes up large areas. However, these are usually hybrid poplars that have been produced by hybridizing the black poplar with American poplar species. These are more vigorous than the parent species. Large-scale afforestation with white poplar was also carried out in the alluvial forests on the Upper Rhine . This tree species is widespread in corresponding locations in the Mediterranean area, but is probably not indigenous to Central Europe. The herbaceous layer of the softwood floodplain forests is not very characteristic. Most of them are widespread forest floor herbs mixed with perennials on the banks. Due to the permeable sand or gravel soil, softwood alluvial forests are not very wet outside of the flood periods. Due to the constant relocation of the soil due to floods, softwood forests are raw soil locations. Soil type is a Syrosem , in the valleys of the Alpine rivers it is often a raw limestone floodplain or rambla .
In areas that are less frequently flooded, hardwood meadows are adjacent .
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