Digital innovation, agricultural productivity growth and environmental sustainability: A randomized evaluation in Nigeria

In the face of climate change, the strong emphasis on increasing inorganic fertilizer application in Sub-Saharan Africa will likely be associated with increased greenhouse gas (GHG) emissions, especially nitrous oxide. Yet, traditional extension systems in the region typically provide generalized ‘blanket’ fertilizer recommendations. Within this context, a digital nutrient management tool has been co-developed to support the transition from the provision of generalized to site-specific recommendations. However, there is thin empirical evidence on the role of such tailored digital extension in mitigating the environmental footprints of expanding fertilizer use in low-input settings. Using a three-year randomized controlled trial in northern Nigeria, this paper analyzes the impact of farmers’ access to site-specific nutrient management recommendations, provided through the digital tool on the environmental sustainability of maize intensification. The primary outcome of interest is GHG emission intensity, measured as kilogram carbon dioxide equivalent emissions per ton of maize output. Our results show that the use of a digital tool to provide site-specific recommendations to the treatment farmers led to an increase in maize yield, and a reduction in GHG emissions intensity compared with the control farmers, who were exposed to blanket recommendations. While we find a considerable maize productivity-increasing effect, the effect size of GHG emission intensity reduction is relatively small. In addition, we find some evidence of heterogeneous effects of the intervention. Overall, our findings suggest that the use of digital tools can support productivity increase with limited carbon footprints through more efficient fertilizer use, which can promote climate change mitigation.