Chronosequential initial evolution of soils and freshwater resources of a barrier island (example Ostplate Spiekeroog)

点击翻译按钮获取中文摘要

Barrier islands, formed by the energy of wind, currents and waves are fragile ecosystems. Morphodynamic changes of barrier islands and the consequences for soils and underlying freshwater reservoirs are of major interest for coastal environments and the drinking water supply of the islands. Starting as a flat and bare sand flat, the young Ostplate changed within only 80 years to an area covered with vegetation with a elongated west-east running line of high dunes, below which freshwater reservoirs have already formed. This evolution is well documented with aerial images and vegetation maps. The aim of this project is to study the initial pedological and hydrogeological processes associated with the geomorphological changes within a known time-frame. Initial soil developing processes and the chronosequential alterations of the soils from the dunes, salt marshes and central flat sands will be investigated as well as the weather and inundation induced variability for the latter. Thickness, extent, age and dynamics of the freshwater reservoirs will be studied and both past evolution as well as future development will be evaluated by means of numerical modeling. In addition, the hydrochemical processes along a flow-path from infiltration into soils to submarine discharge within the freshwater body will be investigated. The protected Ostplate, largely undisturbed by humans, is an ideal site for the planned study, as the time-scales of the dynamic evolution are known. The fact that the Ostplate is not a barrier island by itself is irrelevant with regard to pedological and hydrogeological processes.