Land Use Change in New Spain: A Three-Dimensional Historical GIS Analysis

The introduction of European livestock into the New World resulted in extensive land use changes. Studying the spatiality of these changes as they actually transpired in a three-dimensional landscape can enhance our knowledge of the environmental transformations that accompanied colonization. This article focuses on a case study area in New Spain, roughly equivalent to present-day Mexico, wherein forty-seven sheep ranches were established through viceregal land grants between 1535 and 1610. An integration of fieldwork, textual analysis of land grants, and imagery analysis enables these ranches to be mapped in a three-dimensional geographic information system (GIS) environment. Once mapped in a GIS, the spatial statistics of each ranch's elevation, slope, and aspect (slope orientation) can be calculated to identify spatio-temporal patterns of land use change. These spatio-temporal patterns can be interpreted within the highly localized contexts of land granting to amplify our understanding of human–environment interaction in New Spain. This article's key findings are that grantees harbored a persistent preference for south-facing land; ranches clustered most heavily on isolated elevations; viceregal ordinances were effective at keeping livestock away from low-lying, agriculturally productive zones; and, as a consequence of native population decline and forced native resettlements, the midelevations experienced a land use change from semiterraced agriculture to ranching. These results offer a fresh perspective on the local-scale processes of land use change that resulted from the European colonization of the New World.