Holocene landscape development in the marshes of the West Coast of Schleswig-Holstein, Germany

Abstract

The Holocene development of the North Sea coast of Schleswig-Holstein has been governed: (a) by the morphology that existed at the beginning of the Holocene, (b) by sea-level variations, and (c) by local influences, such as compaction of sediments or diking and drainage of the marshes by man. The sediment facies in Dithmarschen in the southern part of the North Sea coast of Schleswig-Holstein is rather uniform. Local differences can be recognized only for the last 4000 years. In contrast, in North Frisia the facies of the Holocene sediments change within short distances in the area of the present-day tidal flats. Areas affected by sediment compaction in the first millennium AD became tidal flats in the 14th century AD. In AD 1634 a storm surge flooded the southern marshes of North Frisia and turned further large areas into tidal flats. The reason for this second invasion of the sea into the cultivated land was mainly the impact of man on the landscape resulting from diking and draining of the marshes as well as from the cutting of peat. The tidal flats in today's southern North Frisia mirror more or less exactly the relief of the base of the coastal Holocene.