Vegetation change during the Bronze Age studied in a multi-proxy approach: use of wood linked to charcoal analysis

Abstract

During recent archaeological excavations in the alpine valley of Montafon, western Austria, a Bronze and early Iron Age settlement cluster located at about 1,000 m a.s.l. was excavated. The human impact on the woodland resulting from these prehistoric settlement activities has been evaluated by the analysis of charred plant macro remains from cultural layers from a hilltop settlement site and two other close-by settlements, all of them encompassing the Early and Middle Bronze Age (19th to 15th century cal. b.c.) and early Iron Age (6th/5th century cal. b.c.). Charred seeds and fruits have provided information on the supply of foodstuff while charcoal (anthracological) analyses of firewood have revealed the use of wood and consequently the changes in local woods. The latter analyses suggest that the spruce-fir woodland (Piceeto-Abietetum) was gradually cleared from the Early Bronze Age. During the Middle Bronze Age large amounts of Pinus sylvestris (pine), Betula (birch), Corylus avellana (hazel) and Sorbus (rowan) with some Picea abies (spruce) characterized the woods, and early succession stages indicate clearings. These anthracological studies are corroborated by pollen studies disclosing clearings in the woods since the Early Bronze Age, which gradually expanded during the Middle Bronze Age. Furthermore, several charcoals from a Middle Bronze Age hearth seem to be of the same age, and the pattern of their annual growth-rings suggests the pollarding of broadleaved trees.