UPSC Prelims 2021 Q51: Environment & Ecology – Sustainable Agriculture & Forestry
- (a) 1 and 3
- (b) 1, 2 and 4
- (c) 4 only
- (d) 2 and 3
Answer: (b) 1, 2 and 4
Explanation
Permaculture vs Conventional Chemical Farming
| Statement | Claim | Verdict | Detail |
|---|---|---|---|
| 1 | Permaculture discourages monoculture; conventional favours monoculture | TRUE | Permaculture uses polyculture / companion planting / guilds - deliberately diverse. Conventional chemical farming = monoculture (single crop) for mechanised efficiency. |
| 2 | Chemical farming raises soil salinity; permaculture does not | TRUE | Excessive chemical fertilisers + irrigation cause secondary salinisation in conventional farming. Permaculture minimises inputs and uses mulch/compost, avoiding salt build-up. |
| 3 | Chemical farming works in semi-arid; permaculture does not | FALSE | Permaculture actually thrives in semi-arid regions through water harvesting, mulching, keyline design and drought-tolerant polycultures. Bill Mollison's permaculture originated in Australia's arid zones. |
| 4 | Mulching is very important in permaculture but not necessarily in chemical farming | TRUE | Mulching (covering soil with organic matter) is a core permaculture principle - conserves moisture, adds carbon, suppresses weeds. Conventional farming often keeps soil bare between rows. |
Correct: 1, 2 and 4. Answer: (b).
Answer: (b) 1, 2 and 4.
Why each option is right or wrong
- (a) Incorrect. Statement 3 is factually wrong - permaculture works well in semi-arid regions.
- (b) CORRECT. Statements 1 (polyculture vs monoculture), 2 (chemical farming causes salinisation) and 4 (mulching is core to permaculture) are correct. Statement 3 is wrong.
- (c) Incorrect. Statements 1 and 2 are also correct.
- (d) Incorrect. Statement 3 is wrong; statement 2 is correct.
Key point
Permaculture = polyculture + mulching + minimal chemicals + suits semi-arid regions. Conventional chemical farming = monoculture + often no mulch + causes soil salinisation. Statements 1, 2, 4 correct. Statement 3 (semi-arid unsuitable for permaculture) is FALSE.
Remember
Permaculture farming differs from conventional chemical farming in that (1) it discourages monoculture and uses polycultures, (2) it avoids soil salinisation caused by chemical inputs, and (4) it centres mulching as a core practice. Statement 3 is wrong - permaculture actually works well in semi-arid regions. Answer: (b) 1, 2 and 4.
Common mistakes
- Assuming permaculture is only for wet, temperate zones. It actually works well in semi-arid regions - Bill Mollison's original work was in Australia.
- Confusing mulching (covering soil) with tilling (turning soil). Permaculture avoids tilling and mulches heavily.
- Not knowing secondary salinisation is a major issue in irrigated chemical agriculture (Punjab, Haryana, parts of Deccan).
Exam tip
Permaculture design principles: Observe + interact, catch and store energy, use edges, small-scale intensive, polyculture guilds, mulch heavily, no bare soil, natural water flow. Coined by Bill Mollison and David Holmgren (Australia, 1978). Works in ANY biome.
Sources
- Bill Mollison - Permaculture: A Designers' Manual
- FAO - Save and Grow: Farming Systems for Sustainable Intensification