Soil Nutrient Dynamics and Maize Productivity in Sub-Saharan Africa: A Case of Integrated Plant Nutrition

Abstract

Soil fertility decline remains a pressing challenge for agricultural productivity across Sub-Saharan Africa, where maize serves as a staple crop for millions of households. This study examines the effects of integrated plant nutrition approaches on maize productivity, with a focus on combining organic and inorganic amendments to optimize soil nutrient availability. Field experiments conducted across varied agro-ecological zones in South Africa and Ghana compared treatments of sole mineral fertilizers, sole organic amendments (compost and manure), and integrated applications. Results revealed that integrated treatments significantly improved soil organic carbon, cation exchange capacity, and microbial biomass while reducing nutrient leaching losses compared to mineral fertilizers alone. Maize yields increased by 28–34% under integrated systems, with notable improvements in nitrogen uptake efficiency. Soil micronutrients such as zinc and boron, often overlooked in conventional fertilizer regimes, were more balanced under organic-inclusive practices, contributing to healthier root development and grain quality. Beyond agronomic outcomes, household surveys demonstrated increased farmer resilience and reduced dependency on costly external inputs. The findings support the growing consensus that integrated plant nutrition not only enhances crop productivity but also sustains soil health over the long term. Policy recommendations emphasize scaling up farmer training programs, improving access to organic inputs, and encouraging region-specific soil testing services. This research underscores the potential of integrated nutrient management as a cornerstone for food security and sustainable soil conservation in Africa’s rapidly changing agricultural landscapes.