High-Resolution Spatial Analysis of Organic and Chemical Nitrogen Fertilizer Sources on NH₃ Emissions

Agriculture is a major source of atmospheric ammonia (NH₃) emissions, driven by synthetic nitrogen fertilizers and livestock manure, which significantly influence nitrogen cycling and environmental pollution. This study quantifies the global impact of nitrogen sources on NH₃ emissions using a high-resolution gridded emissions inventory, comparing chemical fertilizers (e.g., urea, ammonium nitrate, etc) and organic fertilizers (cattle, buffaloes, sheep, goats, pigs, and chickens). Results indicated that Asia, North America, and Europe are primary emission hotspots, with urea-based fertilizers and intensive livestock farming as key contributors. Targeted mitigation strategies, such as improved manure management, optimized fertilizer application, and policies like the EU’s NH₃ Emission Ceilings Directive and China’s Zero Increase Action Plan, are essential for reducing emissions. This study provides critical insights into the spatial distribution, magnitude, and policy implications of NH 3 emissions, guiding sustainable agricultural practices to balance food security and environmental protection.