Crack Prelims
← Ecology & agriculture-environment · Sustainable practices
Prelims 2020 · Q80 · Sustainable practices

What is the use of biochar in farming ?

  1. 1.Biochar can be used as a part of the growing medium in vertical farming.
  2. 2.When biochar is a part of the growing medium, it promotes the growth of nitrogen-fixing microorganisms.
  3. 3.When biochar is a part of the growing medium, it enables the growing medium to retain water for longer time.

Which of the statements given above is/are correct ?

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Answer: D. Biochar is charcoal made from plant waste. It can be part of soilless growing media in vertical farming, it provides a home for microbes including nitrogen-fixers, and its porous structure holds water for longer. So all three.

Watch for: Students think biochar is only for open fields and drop the vertical farming statement.

Why the other options are wrong
  • A. Wrong because biochar also helps the medium retain water.
  • B. Wrong because statements 1 and 3 are also correct.
  • C. Wrong because biochar also supports nitrogen-fixing microbes.

Source to check: ICAR publications on biochar; International Biochar Initiative (biochar-international.org)

Answer from the official UPSC key. Written and fact-checked by AI against the official key. Spotted a mistake? Report it.