Fertile Ground for Conflict

Abstract: We study how variations in land fertility affect civil conflicts. We first present a model with heterogeneous land in which variations in input prices (fertilizers) affect appropriable rents and the opportunity costs of fighting. The theory predicts that spikes in input prices increase the likelihood of conflicts, and that this effect is magnified when soil fertility is heterogeneous. We test these predictions using data on conflict events covering all Sub-Saharan African countries at a spatial resolution of 0.5° x 0.5° over the period 1997-2014. We combine information on soil characteristics and worldwide variations in fertilizer prices to identify local changes in input prices. We find that exogenous variations in fertilizer prices trigger more conflicts, especially in cells where soil quality is more heterogeneous. Our paper therefore suggests that land fertility is a signicant determinant of violence.