Reconstruction of environmental conditions for selected cultural periods in an old settlement area
|Location||International Geological Congress,oslo 2008|
|Author||Raab, Alexandra; Vِlkel, Jِrg|
|Holding Date||08 October 2008|
Due to good edaphic and climatic conditions, the Dungau nearby Regensburg (Bavaria, Germany) is one of the oldest areas of settlement in Central Europe with a continuous settlement history since the Neolithic period. At Regensburg-Burgweinting, situated about 5 km south-east of the Roman town centre of Regensburg (UNESCO world heritage), 13 years of archaeological excavation produced an excellent insight into the spatio-temporal distribution of prehistoric cultures from the Linear Pottery culture to the Middle Ages. In contrast, little is known about the environmental conditions during the different prehistoric settlement periods and about the environmental change induced by prehistoric land-use. Within the scope of a DFG research project, funded since 08/2007, studies are carried out on different geoarchives (peat, colluvial deposits and soils) which are situated nearby the ongoing archaeological excavation in order to reveal the environmental settings for selected settlement periods. While pollen analysis and microscopic charcoal analysis on peat profiles provide information about vegetation and fire history, studies on soils and colluvial deposits yield information about land-use. The compiled prehistoric and palaeoenvironmental data will be analysed with a Geographic Information System (GIS).
The main study object is a topogenic mire at a small creek (Islinger Mühlbach) which lies in about 500 - 1000 m distance in southward direction from the archaeological excavation site. The spatial extent and peat stratigraphy of the topogenic mire was investigated by manual drillings. The base of the 362 cm long peat profile 7038-302 from the centre of the mire was radiocarbon dated to 12150 ±78 a BP (Erl-7516, 337-338 cm sediment depth). This age proves a start of peat formation during the Late Glacial and therefore, this peat profile contains the complete settlement history since that time. Based on this information two further peat profiles were gained in the middle part of the mire with a Russian peat sampler. Another three sediment cores were drilled at the margin of the mire with percussion drilling using plastic liners. These three sediment sequences have peat/colluvial-interbeddings which prove alternating periods of peat growth on the mire and soil erosion on the adjacent hillslope.