Long-Term Geomorphic Change in the Maya Lowlands of Central America

Abstract

Prehispanic societies transformed large areas of tropical forest in Mexico and Central America, a region now known as the Maya lowlands, into highly engineered urban and agricultural landscapes, over a period of more than two millennia. This chapter provides an overview of the impacts of the ancient Maya on their environment, with a focus on the history of Maya modification of local and regional geomorphic systems during the late Holocene. An overview of the geomorphology of the Maya lowlands is provided, with key examples of Maya interactions with and modifications of the landscape. The Maya converted natural ecosystems into vast urban and rural infrastructure with locally attuned water management systems that included reservoirs, wetland fields and canals, terraces, field ridges and water temples. Evidence for increasing Maya deforestation, carried out for urbanization and agriculture, is preserved in the form of deep sequences of anthropogenic sediments that cascaded through catchments, buried Maya infrastructure and paleosols, silted in reservoirs, waterways, floodplains and wetlands, and accumulated on lake bottoms. The use of proxies for ancient Maya land-use intensity, such as inorganic and organic geochemistry and stable carbon isotopes, soil organic matter and mineral magnetism, are briefly reviewed. The Maya geomorphic impacts were sufficiently severe that centuries of erosion left a region-wide anthropogenic chronostratigraphic marker known as the ‘Maya Clay’ across much of the southern Maya lowlands. The greatest geomorphic impacts of the Maya in the region began to diminish by c. 1000 BP, in response to social and political upheavals that have been referred to as the ‘Maya Collapse.’ Geomorphological, geoarcheological, and paleoenvironmental investigations have provided data that can be used to quantify Maya-mediated environmental impacts and test hypotheses about climate and environmental drivers of societal ‘Collapse.’