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

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UPSC Prelims 2020 · Agriculture · Farming Green

What is the use of biochar in farming?

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

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Answer: (d) 1, 2 and 3

Porosity explains all three: it’s a light growing medium, it houses microbes, and it holds water.

1. ✓ CORRECT Light, porous and long-lasting, it works well in soil-less growing mixes.

2. ✓ CORRECT Its pores shelter microbes, including nitrogen fixers, and hold nutrients.

3. ✓ CORRECT The huge internal surface holds water like a sponge.

Biochar = charcoal made by heating crop waste with little oxygen (pyrolysis). It also locks carbon in the soil for centuries.

Crop residue → pyrolysis (low oxygen) → biochar → richer, wetter soil + stored carbon

(a) Drops water retention — the most direct physical property of a porous material.

(b) Keeps only the microbe effect. Porosity also makes biochar a light growing medium and a water store.

(c) Drops the microbe effect, thinking biochar is inert charcoal. Its pores give microbes, including nitrogen fixers, a home.

“Vertical farming” sounds too modern for charcoal, so people drop statement 1. Biochar is a common growing medium there.

🔒 Biochar: porous charcoal from biomass · holds water and nutrients · houses microbes · stores carbon.