Soil resources and anthropogenic changes at the Tibes site, Ponce, Puerto Rico

Soil and landscape analyses were conducted at the pre-Columbian civic-ceremonial center of Tibes in south-central Puerto Rico, near the city of Pence, to characterize intrasite activity areas and to evaluate soil resources available to the original horticulturists who settled there. Comparisons were made of chemical signatures of activity areas and off-site soils, including relative concentrations of soil elements that characteristically accumulate as a result of human activities. In particular, total phosphorus contents were determined for anthropogenic and non-human-influenced soils and presented as marker values for this and similar sites in the region. Also examined was the relationship between site selection and landscape attributes, including characterization of local soil types in terms of fertility and physical structure, the effects of alluvial processes on the site, and intra-site variation in soil characteristics. Soils changed from west to east across the site: those closest to the western margin and the Rio Portugues contained more silt and fewer rocks than the pebbly, clayey soils of the hillside footslopes to the east. The overall characteristics of the site seas suggested a stable climate throughout the period of site occupation Clear differences existed in phosphorus content of soils from cultural features, non-feature site areas, and off-site localities, providing a general means of chemically identifying these three types of soils at similar sites.