Late Pleistocene to Early Holocene natural and human influenced sediment dynamics and soil formation in a 0-order catchment in SW-Germany (Palatinate Forest)

Abstract

This paper presents the dynamics of sedimentation processes and soil development of a steeply sloping 0-order catchment in the sandy Lower Bunter of the south-western mid-range mountains in the Palatinate Forest (Germany) during the transition period from the Late Glacial to the Early Holocene. Field investigations, chemical, physical, micromorphological and anthracological analyses revealed a complex palaeosol-sediment sequence along the thalweg of a dry valley, where a significant amount of the sediment from the adjacent slopes had been captured. The deposition of aeolian sands in the lowermost sediment layer took place in the early Late Glacial. The subsequent sediments were deposited by slope-wash and aeolian processes. It contains a higher amount of silt and dates from the Allerød. The occurrence of Laacher See Tephra (LST) indicates that this sediment has been near the surface around 12,900 cal. BP. It also shows characteristics of palaeosols similar to the Usselo/Finow soils in north-eastern Germany. In the overlying material, the amount of root remnants, other organic matter and rounded bone fragments possibly indicates the presence of people in this area. On top, alternating reddish brown, coarse to fine sand and small, partly rounded stones with some small intercalated aggregations of humic material rich in charcoal dating to between 11,000 and 12,000 cal. BP were deposited. The layers are overlain by clearly visible and evenly distributed wavy clay-illuviation bands typical for a Luvisol. In the upper metre, a Cambisol has developed. The sediment structure shows typical features of a flash-flood event in the Preboreal. The stratigraphy suggests that phases of sedimentation caused by water and aeolian erosion took place in the Allerød, Younger Dryas, and Preboreal. Discussion considers climate driven natural processes as well as the possibility that the manipulation of forest vegetation by fire through sedentary Mesolithic hunter–gatherer groups created open areas and enabled intensive soil erosion at a local scale.