Multi-site archaeobotanical analysis reveals wood-fuel supply woodland impact and land use around Roman urban centres: The case of Barcino (Barcelona NE Iberia)

Abstract

Woodlands are especially important spaces for city fuel provisioning. During Roman times urban centres carried out numerous activities with frequent wood-energy requirements, and as a result, they potentially impacted the composition of the surrounding forests. Considering this premise, this study discusses the wood fuel economy and the configuration of the landscape around the Roman colony of Barcino (present-day Barcelona), located on the NW Mediterranean coast. We approached the topic starting from an analysis of wood charcoal fragments and pollen remains sampled from several rescue archaeological excavations along the perimeter wall of the Roman city, in order to shed light on the composition of the urban wood fuel exploited and the land cover of the suburban area between the 1st and the 6th centuries CE. The charcoal analysis revealed that most of the fuel procured for Barcino came from holm oak woodlands, with Quercus ilex, Arbutus unedo and Erica arborea woods predominantly being harvested. Furthermore, the composition of the fuel charcoal debris appeared similar in the different excavation-sectors as well as constant through time, suggesting the existence of a fuel supply economy common to the whole city and sustainable woodland management to fulfil these needs. Moreover, pollen analysis detected an important deforestation process in the ager of the city, accompanied by an increase in cereal and vine cultivation. In addition, either pollen and/or charcoal findings assessed the introduction of new fruit trees in the area (Castanea sativa, Juglans regia, Maloideae, Citrus sp., Punica granatum, Prunus sp.). Overall, these data suggest the fragmentation and ever-increasing shift of forested areas in the hinterland of the Barcelona plain, as well as on the hills.