Asociaciones fitolíticas en estructuras del espacio agrario del sitio Yasyamayo (valle de Yocavil, Argentina) durante el período Tardío (1000-1480 dc)

The objective of this research is to establish the effects produced by human activities on the phytolithic composition within a circular structure located at the Yasyamayo site (Yocavil valley, Tucumán, Argentina) during the Late Period (1000-1480 AD). To achieve this, the phytolithic assemblage of this structure was analyzed and compared with those from a stratigraphic sequence without anthropic activity and other from an agricultural terrace. The results showed some differences between the compared sets and, together with available stratigraphic and geochemical data, support the hypothesis of the residential use of the circular structure, perhaps as an agricultural outpost, and reaffirmed the agricultural function of the cultivation terrace. Additionally, paleoenvironmental conditions reinforced for a drier pre-occupational stage than the current conditions were reaffirmed, coinciding with the Medieval Climatic Anomaly. The presence of an arid and semi-arid paleoenvironment with some humid fluctuations was observed for the post-occupational stage, coinciding with the Little Ice Age (1300-1850 AD).