Future scenarios for urban agriculture and food security in sub-Saharan Africa: Modelling the urban land-food system in an agent-based approach

Abstract

Food systems in sub-Saharan African cities are increasingly pressured by rapid urban sprawl and socio-economic changes. While land conversion from cropland to built-up area is limiting the opportunity for urban agriculture, food demand is rising because of population growth and changing diets. Meanwhile, socio-economic segregation – often associated with urbanization - can hinder access to food. For the case study of Kampala (Uganda), we spatiotemporally model the land-food system using an agent-based approach. Based on 747 household surveys, we recalibrated the Agent-based model of Social Segregation and Urban Expansion (ASSURE) by Vermeiren et al. (2016) and included food system dynamics to assess future trajectories (2020–2040) of Kampala's dependency on urban agriculture. While food that is both produced and consumed within the city is often considered the most resilient food source in times of crisis, we show that it is particularly this source that is threatened. Overall, about 10 % of the urban and peri-urban agricultural land in Kampala is projected to disappear by 2040. This may lead to decreased levels of food security and dietary diversity, particularly for households that strongly rely on urban agriculture. Information on the links between urban growth and local food provision is essential for planners who aim to develop strategies for more secure, just and sustainable African urban food systems.