ICAR’s study on Climate Change and Unbalanced Fertilizer

Why in news?

A study conducted by the Indian Council of Agricultural Research (ICAR) reveals that climate change and unbalanced fertilizer use are significantly degrading soil organic carbon across India.

• Coordinated by – ICAR’s Indian Institute of Soil Science in Bhopal, it was started in 2017.

Key Findings

• Influence on soil – Organic carbon influences soil chemistry, physics, and biology—critical for soil health.
• Decline in soil organic carbon – It found that unscientific fertilizer use & climate change are degrading organic carbon in arable soils.
• 3 factors – Decide the organic carbon concentration in the soil irrespective of the crops and cropping patterns - temperature, rainfall and elevation.
• Micronutrient deficiency – If the organic carbon is low, then the deficiency of micronutrients in the soil is high, and if the organic carbon is high, the deficiency is low.
• Effect of elevation – Higher land elevations tend to have greater organic carbon content in the soil, whereas, as the elevation decreases from hills to lowlands, the organic carbon levels also decline.
• Influence of temperature – Temperature negatively correlates—hotter regions like Rajasthan and Telangana have less organic carbon.
• Low carbon leads to less heat absorption, more heat reflection & greater greenhouse gas effect.
• Importance of cropping system – Rice & pulse-based systems show higher organic carbon due to water use and microbial activity, whereas, wheat & coarse grains correlate with lower organic carbon.
• Regional trends – Wherever imbalanced fertilizer application was there, then the organic carbon in the soil had declined.
  • Haryana, Punjab, Western UP – High fertilizer use (urea, phosphorus) leads to decline in organic carbon in soil.
  • Bihar – Balanced fertilizer use leads to better soil carbon levels.
• Suggestions –
  • ‘Agri-ecological base’ map – Developed to assess how cropping patterns & fertilizer usage influence soil organic carbon across 20 agro-ecological regions.
  • Universal Soil Coverage – Promote cropping and plantation across all soils to enhance organic carbon levels.
  • Targeted Carbon Sequestration – In areas with less than 0.25% soil carbon, governments should promote organic carbon sequestration through improved cropping systems & irrigation.
  • Carbon credit – Offer financial incentives to farmers who successfully trap CO₂ & convert it into organic carbon.
  • Climate-Smart Crop Management – Develop and promote region-specific crop management strategies for climate change  mitigation.  

Reference

The Hindu | ICAR’s study - Climate Change and Unbalanced Fertilizer