Farm Size, Soil Investment, and Quality: Theory and Evidence from a Panel Data Set in Tanzania

Achieving sustainable agricultural development is a vital concern as soil degradation poses a growing threat to the livelihoods of smallholder farmers in the developing world. Previous literature has highlighted the potential for rural population growth to exacerbate this concern by leading to smaller farm sizes and crop production on marginal land. This paper uses a theoretical model to demonstrate a countervailing effect consistent with the work of Esther Boserup: Smaller farm sizes can encourage greater intensification and investment in the soil. Using panel data from the Tanzania National Panel Survey, I test the model and find some evidence consistent with this effect. Smaller farms are associated with greater organic, but not inorganic, fertilizer application, and higher levels of some soil quality proxies. These results suggest that if key resource and information constraints are overcome, population growth need not be an obstacle, and can be a boon, to sustainable agricultural development.