The widespread use of nitrogen fertilizers over the past century has significantly enhanced agricultural productivity and improved global food security. However, improper nitrogen management has led to severe environmental challenges, including air, water, and soil degradation, biodiversity loss, and accelerated climate change.
A comprehensive report recently released by the Food and Agriculture Organization of the United Nations (FAO) highlights the critical need for sustainable nitrogen use. Presented at FAO headquarters in Rome, the report examines the impact of nitrogen on agrifood systems and offers actionable recommendations for minimizing its adverse effects.
Nitrogen’s Role in Agriculture and Beyond
Nitrogen is a vital element for the growth of plants, animals, and humans. It is an essential component of amino acids and proteins that form the building blocks of life. The development of the Haber–Bosch process in the early 20th century marked a significant breakthrough, enabling the conversion of atmospheric nitrogen into ammonia, a key fertilizer component.
Today, human activities introduce approximately 150 teragrams (Tg) of reactive nitrogen into the environment annually, more than twice the pre-industrial levels. Projections suggest that this figure could rise to 600 Tg per year by 2100, exacerbating nitrogen loss and its associated environmental impacts.
Livestock farming is a significant contributor to nitrogen emissions, accounting for about one-third of total human-induced emissions. Other major sources include synthetic fertilizers, land-use changes, and manure management. Regions such as North America, Western Europe, and parts of Asia experience the most severe nitrogen pollution due to decades of excessive fertilizer use. In contrast, many low- and middle-income countries face nitrogen depletion caused by limited access to fertilizers, leading to soil degradation and reduced productivity.
Balancing Benefits and Risks
Efficient nitrogen use in agriculture is essential for preventing soil degradation, replenishing nutrients, and increasing crop yields. However, overuse leads to numerous environmental and health issues, including air and water pollution, greenhouse gas emissions, and respiratory and cardiovascular diseases.
Sustainable nitrogen management focuses on minimizing nitrogen losses, reducing external inputs, and promoting recycling. This approach aligns with global efforts to combat climate change and protect biodiversity.
Recommendations for Sustainable Nitrogen Use
The FAO report provides several key recommendations to improve Nitrogen Use Efficiency (NUE) and mitigate environmental impacts:
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Fertilizer Industry Practices: Urgent measures are needed to reduce greenhouse gas emissions during fertilizer production. Wasteful losses during storage, transport, and application must also be minimized.
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Biological Nitrogen Fixation: Governments should promote crop rotations with leguminous crops like soybeans and alfalfa, which naturally fix atmospheric nitrogen into the soil.
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Manure Management: Livestock farmers should adopt best practices for manure management, reducing nitrogen losses while maximizing its use as a resource in agriculture.
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Organic Fertilizers and Spatial Planning: Policies should encourage the use of organic nitrogen sources and promote livestock redistribution to avoid overconcentration in specific regions. Circular bioeconomy approaches can further enhance sustainability.
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Climate Action Integration: Sustainable nitrogen management should be incorporated into climate mitigation strategies to meet the Paris Agreement’s 1.5 °C target.
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Commitments to Reduce Pollution: Governments should set national targets to reduce nitrogen emissions, including ammonia and nitrates, in line with biodiversity conservation goals.
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Food Waste Reduction: Efforts to minimize food loss and recycle inedible food as livestock feed can significantly reduce nitrogen waste.
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Investment and Development: Sustainable nitrogen management should be integrated into agrifood development projects, with investments in efficient fertilizers and organic residue recycling to minimize resource waste.
A Path Toward Sustainability
Adopting sustainable nitrogen management practices is essential to achieving the Sustainable Development Goals by 2030. These practices can enhance food production, particularly in low- and middle-income countries, improve health outcomes by reducing harmful emissions, and protect ecosystems from nitrogen-related pollution. By prioritizing nitrogen use efficiency, governments, industries, and stakeholders can contribute to a more sustainable and equitable agrifood system that balances productivity with environmental stewardship.
