Stable carbon isotope signature of ancient maize agriculture in the soils of Motul de San José, Guatemala

Abstract Soil profiles collected from a 2.5‐km transect radiating from the Maya center of Motul de San José were analyzed for the stable carbon‐isotope composition of their soil organic matter. The residues of maize ( Zea mays ), the only C 4 plant known to have been cultivated in this area by the ancient Maya, impart a carbon‐isotope signature to the underlying soil organic matter reservoir that is distinct from that produced by the native C …