Nitrogen fertilizer use in agroecosystems: current practices, policies and recommendations for efficiency improvement

Abstract Purpose Ensuring global food security for a growing population has intensified the reliance on nitrogen (N) fertilizers to maintain high crop yields. However, dependency on N fertilizers has led to increased over-fertilization, declined N use efficiency (NUE), and exacerbated environmental and agronomic challenges. Methods This review synthesised current fertilization practices, N-related policies, and empirical evidence regarding the consequences of excessive or unbalanced N application. Results The environmental consequences of excessive or unbalanced N application included increased soil acidification, fertility decline, crop productivity decline, nitrate contamination and greenhouse gas emissions and highlighted the implications for long-term agricultural sustainability. As a result, a set of integrated strategies was proposed to enhance NUE while safeguarding soil health and included precision agriculture implementation, cover cropping, microbial inoculation, conservation tillage and organic amendment application. Practical limitations and contextual barriers to adoption, particularly in smallholder-dominated systems, were also examined and actionable recommendations in policy, research and extension were outlined. Special emphasis was placed on the role of inclusive and farmer centric extension services where farmer voices are heard to address their need, data-driven decision-making systems, fertilizer innovation, circular N management and cross-sectoral collaboration. Conclusion Collectively, this work offers a holistic framework for advancing sustainable N management and help to build resilient agricultural systems under intensifying environmental and climate pressures.