Is terraced agriculture 'sustainable?': a view from the Middle Utcubamba Valley, Peru

Agricultural terraces have a number of attributes that make them useful for managing erosion, shaping hydrology, and enhancing agricultural productivity. These characteristics, as well as their widespread construction by pre-industrial agricultural societies, have made them popular elements of plans to develop "sustainable" agriculture, both through the rehabilitation of relict terraces and the construction of new terrace systems. However, many of these projects have met with limited success and have been abandoned or sidelined soon after their implementation. Here, we attribute some of these challenges to a lack of alignment between the mechanical benefits of terraces and the motivations and goals of contemporary farmers. In turn, we suggest that the mismatch between solutions and problems may be rooted in the fact that NGOs and researchers have insufficiently considered the social, economic, and environmental contexts of past and present agriculture and overprioritized technological solutions to socioeconomic and political problems. As a case study, we investigate histories of terraced agriculture in the Middle Utcubamba Valley (MUV) of northeastern Peru, located within the Chachapoya cultural region. We demonstrate that the long-term viability of terracing in the MUV before the sixteenth century Spanish invasion of the region was dependent on a particular combination of socioeconomic circumstances and agricultural logics, which are no longer present today. Based on this history, we argue that terraced agriculture is––in and of itself––neither "sustainable" nor "unsustainable." Rather, its effectiveness depends on how it operates within dynamic sets of socio-natural relations.