Results from a large scale soil mapping on the North Frisian mainland indicate, that field characteristics, particularly the grain-size, bedding, and degree of compaction, with in general determine the soil units mapped, are closely correlated with each other and with other field and laboratory data. Exchangable ions and the Ca/Mg-ratio, however, indicate no explainable connections with the soil units and with most of the other field characteristics but are determined postsedimentarily by processes of the development of soil and landscape, such as desalting and decalcification, silicate weathering, fresh- and salt-water innundations, salty precipitations, salty groundwater and fertilization. Therefore the Ca/Mg-ratio is not suitable to differentiate between more clayey compacted Knick-marsh soils and less clayey permeable Klei-marsh soils. The results confirm that marsh-soils may only be classified and mapped by means of all available field-data which have to be supplemented by laboratory investigations.

All values represent the means of the samples taken (see sample amount). Contents of exchangeable ions were originally given in mval/100 g soil and were recalculated to mmol/kg soil (Na, K: 1 mval = 1 mmol; Ca, Mg: 1 mval = 1/2 mmol).

Supplement to: Prange, Werner; Brümmer, Gerhard; Weber, Ernst (1974): Untersuchungen zur Kartierung und Klassifizierung der Böden in der Marsch. Meyniana, 25, 59-86