Historical soil erosion and land-use change during the last two millennia recorded in lake sediments of Frickenhauser See,northern Bavaria,central Germany

Abstract

Based on palaeolimnological investigations on a 1275 cm long lacustrine sediment record, sediment yields (SY) and denudation rates (DR) for the last 2000 years were reconstructed from Frickenhauser See, a small lake in central Germany. SY and DR generally correspond with the human land-use history derived from pollen analysis and reveal a drastic interruption of natural processes starting in the eleventh century AD. SY increased over 350-fold from 0.9 t/km² per yr to 328 t/km² per yr in response to deforestation and subsequent soil erosion. The average denudation rate within the catchment area is 81 mm for the last 2000 years, most of which occurred between AD 1100 and 1870. Taking into account that only one-third of the catchment area is suitable for agriculture, the cumulative soil loss from agricultural fields is around 240 mm (0.31 mm/yr). Historical events such as a widespread abandonment period (AD 1300—1450) and the Thirty Years War (AD 1618—1648) are reflected in the pollen record but cause only minor fluctuations in reconstructed sediment yields. This study demonstrates that by applying a multiproxy approach lacustrine sediments provide an excellent archive to reconstruct the effects of human land use on the geomorphological process system and to identify human—environment interactions.