The gathering of woodland resources and their use as fuel had been important activities for the III millennium B.C. and Early Bronze Age communities that occupied Perdigões. Wood charcoal recovered along the fieldwork campaigns in several archaeological structures are testimonies of that. An anthracological study carried out in collaboration between ERA Arqueologia, University of Kiel and the Archaeosciences Laboratory of the Directorate-General of Cultural Heritage, allowed the identification of species that were being exploited during this period.
Charcoal fragments were recovered manually and through flotation of sediments from several occupation contexts in the site: pits, post-holes, ditches and profile. A total of 610 charcoal fragments were analyzed under the microscope of reflected light (x100/x200) for taxonomic identification (Schweingruber, 1990).
During the 1st half of the III millennium BC, in the structures associated to the Timber Circle was identified the presence of tree wood, namely pine (Pinus pinea/pinaster and Pinus sp.) and probably holm oak (Quercus sp. (evergreen)). Based on this study, the use of shrub species have occurred later, between the 1st half and the half of the III millennium BC, where the presence of wild olive tree (Olea europaea) and strawberry tree (Arbutus unedo) was identified. A higher frequency of wood from shrubs, strawberry tree (Arbutus unedo), heather (Ericaceae) and mastic tree (Pistacia lentiscus) along with holm oak (Quercus sp. (evergreen)) as dominant species and the disappearance of pine in the assemblages, mark, from the “Bell beaker” phase until the Early Bronze Age, a change in the acquisition modalities of the wood for fuel in these periods. The charcoal analyzes in general corroborate with the expected landscape in the region (Capelo and Vila-Viçosa, 2015) and with the pollen record (Danielsen and Mendes, 2015).
Although the charcoal fragments were deposited in anthropogenic structures it is not possible, for now, to determine a direct association with to the functionality of the contexts, due to their probable secondary deposition (Chabal, 1992). However, the results characterize the acquisition modalities of wood by these communities during the several occupations of the site, and these must have been, most probably, aligned with the functionality and the activities carried out during the occupation.
The data here presented will be published in a paper in preparation and they will integrate a broader on-going study in the Perdigões project.
Image – Transversal section of a charcoal fragment of Pinus pinea/pinaster, from the [676] deposit, Timber Circle (1st half of the III Millennium).
References:
Capelo, J., Vila-Viçosa, C. (2021) Vegetação do Alentejo. In: Capelo, J., Aguiar, C. (coord.) A Vegetação de Portugal. Edições Lisboa Capital Verde Europeia 2020. Imprensa Nacional.
Chabal, L. (1992). La représentativité paléo-écologique des charbons de bois archéologiques issus du bois de feu. Bulletin de la société botanique de France. Actualités Botaniques, 139(2-4), 213-236.
Danielsen, R., Mendes, P. (2015). Os Perdigões (Campanha 2013) Relatório de Palinologia. Trabalhos do LARC 6. Lisboa
Schweingruber, F.H., (1990). Anatomy o f European woods. Haupt, Bern, Sttutgart.