RECONSTRUCTING PREHISTORIC LAND USE FROM THE SEDIMENTS OF LAGUNA ESPEJO, OAXACA, MEXICO

Archaeological research carried out over the past ~30 years in the Lower Río Verde Valley of Oaxaca, Mexico has revealed evidence of occupation since the Archaic period. Significant periods of occupation date as far back as the Middle Formative period when agricultural communities began to develop into large-scale political centers. The major increase in the population of the Valley had repercussions for the environment. Paleoecological research has taken a multi-site approach within the valley so as to reconstruct spatial and temporal environmental change. This research is contributing to a larger archaeological project focused on understanding Prehispanic environmental change and how it may have contributed to population growth and social change in the region.

This paper presents an analysis of one of the southernmost freshwater lagoons in the valley, Laguna Espejo. The lagoon is situated west of the Río Verde, covering about ca. 3 km². At the present there is little evidence of prehispanic sites in the immediate vicinity of Laguna Espejo, although only unsystematic archaeological reconnaissance has been carried out in this area. The paleoecological sampling consists of four sediment cores. The macro-charcoal and carbon isotopic data indicate agriculture was occurring close to the lake during the early Terminal Formative (~1990 cal yr B.P.), but was likely absent during the late Terminal Formative. Lithostratigraphy and radiocarbon analysis point to a significant hiatus in sedimentation at some time during the Classic to Early Postclassic Periods. Following this sediment hiatus, which appears to have lasted ~750 years, agricultural proxies indicate that the region about the lake margin was used intensively for maize agriculture for much of the Late Postclassic period. Anthropogenic disturbance about the lake ended during the latter part of Late Postclassic but well before Spanish Conquest. The data from Laguna Espejo will be placed within the context of the broader region of the Río Verde and its occupational and landscape history.