Lateglacial and Early Holocene environments inferred from a tufa deposit at Fyledalen, S. Sweden

Abstract

A reinvestigation of a tufa deposit in Skåne, including a number of biostratigraphical methods and chronology was carried out. The tufa was formed in a paludal environment during the time period c. 9,500 to 8,000 BP. This period is characterised by exceptional low lake levels and high summer temperatures in southern Sweden. This may suggest that optimal conditions for tufa formation at the site coincided with warm and dry climate conditions, a low groundwater table, and high evaporation. During periods with colder conditions and/or higher groundwater table peat was deposited. The changes in the local environment at and around the site were inferred from the biostratigraphical records of pollen, plant macrofossils, molluscs, and insects. The results demonstrate a development from a dwarf shrub tundra during the Late-glacial, which turned to an open birch/pine woodland around 10,000 BP. At c. 9,000 BP hazel and birch were probably the dominant tree species in the woodland. The mollusc record suggests that the woodland remained relatively open until c. 8,500 BP when tree taxa such as alder, oak and elm became established in the Fyledalen valley. The site remained a marsh throughout the studied period, however, the results indicate a succession of different marsh plant communities.