The “Black Floodplain Soil” in the Amöneburger Becken, Germany: a lower Holocene marker horizon and indicator of an upper Atlantic to Subboreal dry period in Central Europe?

In many sediment profiles of Central European floodplains, a black horizon is found between Late Glacial and middle to upper Holocene sediments. This horizon is rich in clay and humic material, and is referred to as “Black Floodplain Soil” (BFS). Its widespread occurrence in the Amöneburger Becken near Marburg (Hessen) provides some new insights into the period and circumstances of its development. As a polygenetic formation, the BFS is of special importance for paleoecological and archeological research. It was probably supplied with clay and humic substances from the surrounding terrestrial chernozemic soils and therefore, it also has to be regarded as a sediment. It developed mainly in the Boreal and Atlantic periods but did not gain its final characteristics until a following dry period, which led to a lowering of the ground-water table and widespread illuviation in the floodplains, even in former lacustrine deposits.