Which of the following practices can help in water conservation in agriculture?
- 1.Reduced or zero tillage of the land
- 2.Applying gypsum before irrigating the field
- 3.Allowing crop residue to remain in the field
Select the correct answer using the code given below:
Answer & explanation
Answer: (c) 1 and 3 only
Leaving the soil undisturbed (reduced or zero tillage) and leaving crop residue on the field both conserve water, because the residue cover cuts evaporation and lets more rain soak in. Gypsum is a soil amendment for sodic soils, not a water-saving practice.
- ✓ 1. No-till or reduced tillage, together with residue mulch, is the basis of conservation farming because it conserves water and prevents erosion.
- ✗ 2. Gypsum supplies soluble calcium to replace exchangeable sodium in sodic soils. It is used to reclaim such soils and is not a way of saving irrigation water.
- ✓ 3. Crop residue left on the soil surface reduces evapotranspiration (water loss to the air), raises infiltration rates and suppresses weeds.
Remember · Water-saving conservation farming: minimum or no tillage plus a residue mulch. Gypsum is for reclaiming sodic soils, not for saving water.
Sources
- FAO: Conservation tillage for increased crop production (Chapter 8) ↗ “the no-till system of cultivation with crop residue mulches forms a basis for conservation farming because it conserves water, prevents erosion, maintains organic matter content at a high level, and sustains economic productivity. … retaining crop residues on the soil surface with conservation tillage reduces evapotranspiration, increases infiltration rates, and suppresses weed growth.”
- FAO Soils Bulletin: Sodic soils and their management ↗ “Soil amendments are materials, such as gypsum or calcium chloride, that directly supply soluble calcium for the replacement of exchangeable sodium”
Question and answer: UPSC's official GS Paper I (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·