UPSC Prelims Practice Questions — India’s rice fields rank among world’s top methane sources

Q1. The nodal Union agency responsible for compiling India's National Greenhouse Gas Inventory and submitting its Biennial Update Reports to the UNFCCC is:

  • A. The Ministry of Environment, Forest and Climate Change
  • B. The Ministry of Agriculture and Farmers Welfare
  • C. The Ministry of Earth Sciences
  • D. The Ministry of Science and Technology

Q2. In the context of this study, the term 'paddy' is best understood as:

  • A. A drought-tolerant upland variety of rice grown without any standing water
  • B. Rice grain from which the husk has been removed by milling
  • C. A field in which rice is grown under flooded, waterlogged conditions
  • D. The straw residue left in the field after the rice crop is harvested

Q3. In a flooded rice paddy, methanotrophic bacteria are best described as organisms that:

  • A. Produce methane exclusively from acetic acid under anaerobic conditions
  • B. Oxidise methane, thereby reducing the amount released to the atmosphere
  • C. Fix atmospheric nitrogen in the root nodules of all rice plants
  • D. Decompose all soil organic carbon into carbon dioxide only

Q4. The National Innovations in Climate Resilient Agriculture (NICRA), which develops adaptation and mitigation technologies for climate-vulnerable rice regions such as the Eastern Gangetic Plains, is implemented primarily by:

  • A. The Indian Agricultural Research Institute (IARI), Pusa
  • B. The National Bank for Agriculture and Rural Development (NABARD)
  • C. The Indian Council of Agricultural Research (ICAR)
  • D. The Food and Agriculture Organization (FAO), India office

Q5. According to the 2025 satellite-based Global Rice Paddy Inventory, which country was the world's single largest emitter of methane from rice cultivation in 2022?

  • A. India
  • B. China
  • C. Indonesia
  • D. Vietnam

Q6. Which of the following practices is/are correctly identified as a method for reducing methane emissions from rice paddies?

  1. Alternate Wetting and Drying (AWD) — periodically draining the field below the soil surface before re-flooding.
  2. System of Rice Intensification (SRI) — raising rice with reduced standing water and wider spacing.
  3. Direct-Seeded Rice (DSR) — sowing seed directly into the field instead of transplanting into standing water.
  4. Maintaining continuous deep flooding of the field throughout the entire growing season.
  • A. 1, 2 and 3
  • B. 1 and 4
  • C. 2, 3 and 4
  • D. 1, 2, 3 and 4

Q7. Roughly what share of the increase in global paddy greenhouse-gas emissions does the study attribute to the loss of soil organic carbon (driven by continuous irrigation and residue incorporation)?

  • A. About one-quarter
  • B. About one-half
  • C. About two-thirds
  • D. About three-quarters