Biostratigraphical investigations in connection with archaeological dwelling sites at Jansmyra, northeastern Aland

Situated in northeastern Aland and connected with Early Neolithic and Bronze Age dwelling sites is the small mire Jansmyra. Diatom analysis combined with radiocarbon datings of the sediment from Jansmyra was used to determine when and from which stage in the evolution of the Baltic Sea the mire was isolated. The results show that Jansmyra was isolated from the Litorina Sea c. 5900 BP, which corresponds to the Early Neolithic. Pollen analysis was carried out in order to gain information about the vegetation history in, and the human impact on the area from c. 6000 BP to the present. Clear indicators of grazing and sparse finds of Cerealia appear in the Late Bronze Age. An expansion of anthropogenic impact on the vegetation at Jansmyra is observed in the Late Iron Age