India’s Paddy Fields Emerge as a Major Source of Methane Emissions

Context

A study published in Nature Food has reported that greenhouse gas emissions from global paddy cultivation have nearly doubled since the 1960s. As the world’s largest rice producer, India contributes significantly to these emissions, particularly methane released from waterlogged paddy fields.

Key Highlights

• Global paddy cultivation emitted nearly 1.1 billion tonnes of CO₂ equivalent annually during 2011 – 2020, representing a 90.4% increase over the 1961 – 1980 period. Around half of this increase is linked to the decline in soil organic carbon.
• Waterlogged paddy fields create oxygen deficient conditions that favour methane-producing microorganisms, making eastern India a major methane emission hotspot.
• India’s area under paddy cultivation has expanded by nearly 25% since the 1970s, with rice occupying around 55% of the country’s rainfed harvested area. Irrigated paddy fields alone emit about 3.9 million tonnes of methane annually, exceeding Germany’s total methane emissions.
• Climate-resilient farming techniques such as the System of Rice Intensification (SRI) and Alternate Wetting and Drying (AWD) have been identified as effective methods for reducing methane emissions.

Key Concepts

Methane (CH₄)

• Methane is a highly potent greenhouse gas with a warming effect nearly 80 times greater than carbon dioxide over a 20 year period.
• Major sources include flooded paddy fields, livestock, and waste management activities.

System of Rice Intensification (SRI)

• SRI is a rice cultivation technique that uses less water, widely spaced young seedlings, and improved crop management practices.
• It enhances productivity while lowering methane emissions and water consumption.

Alternate Wetting and Drying (AWD)

• AWD is an irrigation practice that allows periodic drying of paddy fields instead of maintaining continuous flooding.
• It reduces methane formation by improving soil aeration without significantly affecting crop yield.

National Innovations in Climate Resilient Agriculture (NICRA)

• NICRA is an initiative aimed at promoting climate-resilient agricultural practices and technologies to strengthen adaptation and reduce climate-related risks in farming.

Way Forward

• Expand the adoption of SRI and AWD while improving fertiliser application and crop-residue management to lower greenhouse gas emissions.
• Encourage crop diversification in regions dominated by water-intensive paddy cultivation to reduce environmental stress.
• Strengthen extension services, financial incentives, and procurement support to enable farmers to adopt sustainable agricultural practices and alternative crops.