Towards Sustainable Food Security in Namibia: Agricultural Adaptation under Future Climate and Development Pathways

Abstract

Namibia faces considerable food insecurity challenges exacerbated by an arid climate, low soil fertility, and socio-economic vulnerabilities, with approximately 58% of the population affected. Smallholder agriculture dominates but is characterized by low productivity and reliance on rainfed systems, making the country heavily dependent on food imports. This dissertation investigates the potential of cowpea—a climate-resilient and nutritionally rich legume—to enhance food security, support rural livelihoods, and improve child nutrition through Namibia’s school feeding programs under current and future climate and socioeconomic scenarios. The research is structured into three integrated studies. The first study assesses cowpea production potentials using biophysical crop simulations combined with spatial optimization, focusing on the effects of rhizobial inoculation, irrigation, and fertilization on yields and resource use efficiency. Results demonstrate that inoculated cowpea yields nearly double those of uninoculated crops in northern Namibia, while irrigation further boosts productivity. Improved practices reduce land and water use intensity, highlighting opportunities for sustainable intensification despite scarce water resources. The study also reveals critical trade-offs between water and land usage that influence optimal production strategies in semi-arid conditions. The second study evaluates whether Namibia’s domestic agriculture can sustainably meet the caloric and nutrient demands of the Home-Grown School Feeding Programme (HGSFP). Simulations show that northern regions can fulfill these demands with potential surpluses under improved management, whereas southern regions remain constrained by harsh biophysical conditions. Protein supply meets requirements nationally, especially with fertilization, although fat remains a limiting nutrient. These findings underscore the potential of domestic agriculture as a reliable supplier for the Namibia HGSFP. It highlights importance of improved farming managements and policy support to mitigate climate change impacts and regional disparities. The third study examines the nutritional and socioeconomic impact of integrating inoculated cowpea flour into the maize-based porridge served in schools. Cowpea fortification significantly enhances protein quality and micronutrient density while maintaining cultural acceptance. Linking local cowpea production with institutional demand strengthens smallholder markets, improves farmer incomes, and facilitates sustainable rural development. Together, these studies establish cowpea production, supported by inoculation and integrated water-nutrient management, as a promising strategy for nutritious and sustainable agriculture in Namibia. The research highlights the HGSFP’s potential as a platform for improving child nutrition, enhancing food system resilience, and reducing import dependence. While offering robust technical insights, this thesis recognizes the need for further research on social and institutional factors to translate findings into effective policy and practice. Ultimately, it contributes key evidence to foster adaptive capacity, food security, and sustainable livelihoods in resource-constrained, semi-arid environments.