UPSC Prelims 2016 Q83: Geography – Indian Agriculture & Land Use
Which of the following is/are the advantage/advantages of practising drip irrigation?
1. Reduction in weed
2. Reduction in soil salinity
3. Reduction in soil erosion
Select the correct answer
using the code given below:
- (a) 1 and 2 only
- (b) 3 only
- (c) 1 and 3 only
- (d) None of the above is an advantage of practising drip irrigation
Answer: (c) 1 and 3 only
Explanation
Advantages of drip irrigation
In drip irrigation, water falls drop by drop at the root of each plant through pipes and emitters.
| Claimed advantage | Verdict | Reason |
|---|---|---|
| 1. Reduction in weed | Correct | The soil between plants stays dry, so weeds do not grow |
| 2. Reduction in soil salinity | Incorrect | Salts build up at the edge of the wetted zone; there is too little water to wash them down |
| 3. Reduction in soil erosion | Correct | No flowing water, so no run-off |
Other features:
| Feature | Detail |
|---|---|
| Water saving | 30 to 70 percent over flood irrigation |
| Fertigation | Fertilizer can be given through the same pipes |
| Drawbacks | High initial cost; emitters may clog |
| Scheme | Per Drop More Crop under PM Krishi Sinchayee Yojana |
The bank earlier stored (a) as the key; the official key is (c).
Answer: (c) 1 and 3 only.
Why each option is right or wrong
- (a) Incorrect. Drip irrigation does not reduce soil salinity; it also reduces soil erosion.
- (b) Incorrect. Reduction in weed is also an advantage of practising drip irrigation.
- (c) CORRECT. Drip irrigation gives reduction in weed and reduction in soil erosion.
- (d) Incorrect. Two of the three are real advantages, so 'None' is wrong.
Key point
Drip irrigation: saves water, cuts weeds and soil erosion, allows fertigation; but salts can accumulate around the wetted zone.
Remember
Drip: fewer weeds, less erosion, not less salinity.
Common mistakes
- Assuming less water means less salinity; salts are not leached away.
- Forgetting that weeds need surface moisture, which drip denies them.
- Confusing drip with sprinkler irrigation, which wets the whole surface.
Exam tip
Drip wets only the root zone: no weeds, no run-off, but no leaching of salts either.
Sources
- Indian Council of Agricultural Research — Micro-irrigation technologies
- Department of Agriculture and Farmers Welfare — Per Drop More Crop guidelines