Abstract: | Initial soil development in loess and harbourbasin mud reclaimed by slurry poldering In the Rhenish Brown Coal Strip Mining Area initial soil development was investigated for 6–15 and 15–25 years old loamy-silty loess soils reclaimed by slurry poldering. In the Emden environs the same analyses were applied to 6, 17, and 28 years old silty-clayey harbour-mud soils, also reclaimed by slurry application. The most prominent results when comparing these two types of soil are as follows: The mud soils show higher contents of clay and organic matter. Therefore they reveal more favourable characteristics concerning cation-exchange capacity, soil physical and soil biological properties in comparison to those of the loess soils. In both types of soils cation-exchange-capacity and soil biological activity increase in the Ap-horizon over time. The soil physical characteristics of the mud soils markedly improve in the run of the development, whereas those of the loess soils hardly improve. It remains a subject of discussion, since what stage of development mud soils should be classified as sea-marshes/“Kleimarschen” and loess soils as rendzinas. |