Review of soil fertility status, fertilizer trials, and agronomic opportunities in Southern Ethiopia: focus on Ari, South Omo and Konso zones
DOI:
https://doi.org/10.64171/IJPR.2025.5.1.20-25Keywords:
Soil fertility, Fertilizer trials, Agronomic opportunities, Integrated soil fertility managementAbstract
Soil fertility decline is one of the major constraints limiting agricultural productivity in South Omo Zone, Southern Ethiopia. Understanding the status of soil nutrients, evaluating fertilizer trial results, and identifying agronomic opportunities are essential for improving crop production and ensuring sustainable land management in the area. This review synthesizes findings from published and unpublished studies conducted in Ari, South Omo, and Konso zones, focusing on soil physicochemical properties, nutrient deficiencies, fertilizer response trials, and management practices. The evidence indicates that soils in the study areas are generally characterized by low to moderate organic matter content, nitrogen deficiency, variable phosphorus availability, and emerging micronutrient limitations in some locations. Fertilizer trials consistently demonstrate significant yield responses to blended fertilizers containing N, P, S, and micronutrients compared to conventional fertilizer recommendations. However, fertilizer use efficiency remains constrained by soil acidity, limited site-specific recommendations, and low adoption of integrated soil fertility management practices. The review highlights key agronomic opportunities, including site-specific nutrient management, integration of organic and inorganic fertilizers, soil acidity management, crop diversification, and improved extension services. Strengthening soil testing capacity and promoting location-specific fertilizer recommendations are critical steps toward enhancing soil productivity and sustainable agricultural development in South Omo Zone.
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