Margin for error: Anthropogenic geomorphology of Bajo edges in the Maya Lowlands

Abstract

Abstract Many early Maya cities developed along the edges of large structural or karst depressions (bajos). This topographic position aided growing populations to more effectively capture and store rainwater, a necessity for year-round occupation of interior portions of the Maya Lowlands of Mexico and Central America. Ancient Maya forest clearance on sloping terrain led to accelerated soil loss and the aggradation of the bajo margins. These newly created margins of colluvial lands became a focus of subsequent intensive agriculture and helped underwrite further urban expansion. We document this long-term landscape transformation with data derived principally from field investigations at Tikal, Guatemala, and Yaxnohcah, Mexico, but with reference to other Maya centers in the Elevated Interior Region (EIR). Data are derived from field investigations, interpretation of lidar imagery, and laboratory analyses. We present a model of three variants of bajo margin landscape change with differences attributable to topography, lithology, hydrology, and cultural processes. We present preliminary data on crops that were cultivated on bajo-margin soils. We further describe how agriculture was adapted to evolving bajo margins as evidenced by systems of field walls, terraces, and ditches.