The objective of this study was to use pedological evidence in conjunction with Geographic Information Systems, and soil physical and chemical analyses as means to better understand the agricultural landscape surrounding the ancient Maya city of Uci. Specifically, the query of this thesis is to determine whether there is an association between settlement density and soil resources, and what relationship if any there is between the ancient sacbe of Uci and its surrounding agricultural potential. Stable carbon isotope analysis of the humin fraction of the soil organic matter was conducted on several profiles from karst depressions known as rejolladas near the site center, and from a select number of sufficiently deep profiles along and surrounding the ancient sacbe, and from beneath ancient structures. A strong C isotopic signature of ancient C4 crops was found in a limited number of profiles while a majority of the profiles showed no evidence, or little to inconclusive evidence due to a mixture of C3 and C4 plants in the natural landscape. A majority of the soils surrounding Uci are shallow to extremely shallow and many profiles sampled and studied did not allow for C isotopic analysis. Isotopic evidence along with other soil chemical and physical characteristics suggests that settlement density was linked to soil resources, specifically in the case of the rejolladas proximity to the Uci site center. However, it does not appear that the construction and location of the sacbe was linked to its surrounding soil resources or agricultural potential even though ancient maize crops may have been cultivated sporadically close to the sacbe and nearby structures. The soil resources of Uci are not conducive to the production of large maize crops and the ancient Maya of this area likely utilized maize along with alternative crops, arboriculture, wild game and trade to sustain its population.



College and Department

Life Sciences; Plant and Wildlife Sciences



Date Submitted


Document Type





stable carbon isotopes, soil analysis, humin, ancient agriculture, Maya agriculture, geochemistry