Nitrogen Use Efficiency

Syllabus: GS3/ Agriculture

Context

  • A report by the Food and Agriculture Organization of the United Nations (FAO), highlighted that the rise in nitrogen fertilizers has resulted in biodiversity loss and exacerbated climate change.

About

  • Nitrogen is an essential component of food constituents, particularly amino acids and proteins required for the growth of plants, animals, and humans.
  • Improving Nutrient use efficiency (NUE)is critical for;
    • Reducing excessive use of nitrogen fertilizers,
    • Mitigating environmental pollution, such as nitrate leaching and greenhouse gas emissions,
    • Enhancing crop yields.

Key Findings of the Study

  • Nitrogen Use Trends: Humans introduce approximately 150 teragrams (Tg) of reactive nitrogen annually through agriculture and industry, over twice the pre-industrial levels.
    • This could rise to 600 Tg per year by 2100, driven by climate change, increasing nitrogen losses into the environment.
  • Contributors to Nitrogen Pollution: Livestock farming accounts for about one-third of human-induced nitrogen emissions.
    • Synthetic fertilizers, land-use changes, and manure emissions further exacerbate nitrogen pollution.
  • Regional Disparities: Nitrogen pollution is most severe in regions like North America, Western Europe, and parts of Asia, where fertilizers have been overused for decades.
    • Conversely, in some low- and middle-income countries, restricted access to fertilizers leads to nitrogen depletion, soil degradation, and reduced crop productivity.

Impacts of Nitrogen Pollution

  • Health Impacts:
    • It causes methemoglobinemia (blue baby syndrome) in infants by reducing blood’s oxygen-carrying capacity.
    • It is linked to cancers, reproductive issues, and thyroid problems from long-term nitrate exposure.
  • Environmental Impacts:
    • It leads to eutrophication, harmful algal blooms, and oxygen-depleted “dead zones” in water bodies.
    • It contributes to climate change through nitrous oxide emissions, 300 times more potent than carbon dioxide.

Policy recommendations

  • Fertilizer Production: The fertilizer industry should minimize greenhouse gas emissions during nitrogen fertilizer production.
    • Efforts should also focus on reducing wasteful losses during storage, transportation, and application.
  • Biological Nitrogen Fixation: Governments should promote leguminous crops like soybean and alfalfa to enhance nitrogen fixation through sustainable crop rotations.
  • National Climate Commitments: Integrate sustainable nitrogen management into nationally determined contributions (NDCs) and mitigation actions, targeting reduced nitrous oxide emissions to align with the Paris Agreement’s 1.5 °C goal.
  • Sustainable Practices: Encourage investment in high-efficiency, low-emission fertilizers and promote recycling organic residues to improve system efficiency and reduce environmental pollution.

Concluding remarks

  • Sustainable nitrogen management is integral to achieving the Sustainable Development Goals (SDGs) by 2030, particularly those focusing on hunger eradication, health improvement, clean water, climate action, and preserving ecosystems.
  • Hence governments, industries, and individuals must collectively work towards achieving this goal to ensure a resilient and sustainable future for all.

Source: FAO