Modelling the landscape at the end of the Bronze Age: new archaeobotanical data from Monte Croce-Guardia (Central Italy - Marche Region)

In Italy palaeoenvironmental research reveals that the impact of economic activities on the landscape increased significantly during the Bronze Age: the expansion of cultivation and grazing strongly modified the forest cover, with the use of fire as a common agropastoral practice. Additional climatic oscillations, attested during this time span, could have exacerbated the effects of woodland clearance and affected crop selection and production. We present new archaeobotanical data from Monte Croce-Guardia in Central Italy dated to the Late Bronze Age. The site, excavated by the Sapienza University of Rome, is located on the Apennine ridge at 670 m asl and overlooks a wide territory from the mountain slopes to the Adriatic coast. Modern vegetation is dominated by the mixed deciduous oak forest typical of mid-altitude environments. The settlement appeared in the 12th c. BC, when changes in settlement layout occurred across Central and Northern Italy, and was abandoned at the end of the 10th c. BC during a period of strong cultural transformations in pre-Roman Italy. We identified plant micro- and macroremains recovered from primary deposits such as hearths, working surfaces, and other activity areas located on artificial terraces and housing, covering the entire occupational sequence. We applied archaeobotanical, palynological, and stable carbon isotope analyses to reconstruct plant exploitation, as well as climatic and environmental conditions in the surrounding of the site during the study period. Results show a wide range of cultivated plants, as well as the selection and use of wood resources. The isotopic record provides information on local precipitation patterns and the pollen spectra reveal that Mediterranean trees represented an important component of local vegetation, suggesting different climatic conditions at the end of the Bronze Age. In addition, the abundance of xeric herbs refers to a landscape strongly modelled by human activities like grazing. The preserved plant remains of Monte Croce-Guardia represent an outstanding archaeobotanical assemblage for the study of the Bronze Age in Central Italy and contribute to the reconstruction of past climate and plant exploitation by protohistoric communities in correspondence with important socio-economic and environmental changes.