Nutrient Flow Scenarios for Sustainable Smallholder Farming Systems in Southwestern Burkina Faso

Abstract

The report presents a study on nutrient flows of agricultural livelihood systems dominated by smallholder farms in South-western Burkina Faso. The material flow analysis of nitrogen, phosphorus, and potassium provides a detailed picture of current nutrient flows within, in to, and out of smallholder farms. Such a picture allows quantifying material potentials for sustainable intensification, that is, increasing the ratio of crop yield to mineral fertilizer inputs. Finally, in the pursuit of indicators for sustainable intensification, we propose combining indicators derived from material flow analysis with indicators of socio-economic nature to move from material potential assessments to sustainability assessments. The combination is informed by the criticality concept, a concept which denotes how important a specific material resource is to an anthropogenic system. Based on an existing criticality determination methodology for metals, we sketch the criticality indicator set for the case of nitrogen, phosphorus, and potassium and smallholder farms. Further research should include increasing temporal boundaries to capture cycles longer than a year, the applied temporal boundary in this study. A multi-scale study including villages and landscapes could provide additional insights on the role of water bodies or future .industrial activities in nutrient cycling. In turn, the multi-scale MFAs would provide the necessary indicator values to assess nutrient criticality not only at the smallholder farm level, but also at the village and landscape level. Finally, the material flows could be further characterized with respect to gender, cost/benefits, etc