Which of the following is/are the advantage/advantages of practicing 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.
Contents23
- A1 and 2 only
- B3 only
- C1 and 3 only
- DNone of the above is an advantage of practising drip irrigation
Show answer
Answer: (C) 1 and 3 only
Answer: (c) 1 and 3 only
Drip irrigation delivers water directly to plant roots through pipes and emitters.
Statement 1 — Reduction in weeds (✓ CORRECT):
Since water goes only to plant roots and not the entire field, surrounding soil stays dry.
Weeds don't get water, so they can't grow easily.
Statement 2 — Reduction in soil salinity (✗ WRONG):
Drip irrigation can actually INCREASE soil salinity.
Because water evaporates, salts accumulate near the edges of the wetted area.
This is a listed disadvantage of drip irrigation.
Statement 3 — Reduction in soil erosion (✓ CORRECT):
Water is delivered drop by drop at low pressure, so there is no heavy flooding or surface runoff.
No runoff = no soil washed away = less erosion.
Elimination trick:
If you know drip irrigation causes salinity problems (Statement 2 wrong), you can eliminate options (a) and (d), leaving (b) or (c).
Since drip irrigation obviously reduces weeds, answer is (c).
Drip irrigation covers about 10% of India's irrigated area and is heavily promoted through government subsidies under schemes like PMKSY.
The key trap is that drip irrigation actually increases soil salinity due to salt accumulation at wetted zone edges, contradicting what many students assume.
UPSC is testing precision knowledge of irrigation methods beyond surface-level benefits - students must know both advantages and disadvantages of micro-irrigation systems.
Drip Irrigation: Mechanism & Components
Indian Economy drip irrigation
Drip Irrigation: How It Works & Key Components
Drip irrigation delivers water directly to plant roots through pipes and emitters
Water is applied drop by drop at low pressure, creating localized wet zones
Uses 70-90% less water than flood irrigation
Also called micro-irrigation or trickle irrigation
Basic Mechanism
Drip irrigation is a precision water delivery system where water flows through a network of pipes and is released slowly near plant roots through small openings called emitters or drippers. Unlike flood irrigation that waters the entire field, drip irrigation creates small wetted zones only around each plant.
Key Components
Component | Function | Key Feature |
|---|---|---|
Main Pipeline | Carries water from source | Usually PVC, buried or surface |
Sub-main & Laterals | Distribute water across field | Smaller diameter pipes |
Emitters/Drippers | Release water to plants | 2-8 litres per hour flow rate |
Filters | Remove impurities | Prevents emitter clogging |
Pressure Regulators | Control water pressure | Ensures uniform flow rate |
Water Flow Process
%%{init: {"flowchart": {"wrappingWidth": 460}}}%%
flowchart TD
s1["`**Water Source**
Bore well, canal, or reservoir water enters system`"]
s2["`**Filtration**
Water passes through filters to remove sediments and particles`"]
s3["`**Main Pipeline**
Filtered water flows through main distribution pipe`"]
s4["`**Lateral Distribution**
Water branches into smaller lateral pipes across the field`"]
s5["`**Emitter Release**
Emitters release water drop by drop at plant root zones`"]
s1 --> s2
s2 --> s3
s3 --> s4
s4 --> s5Advantages of Drip Irrigation
Indian Economy advantage advantages
Drip Irrigation Benefits: Water, Weed & Erosion Control
Reduces weeds because surrounding soil stays dry
Prevents soil erosion due to low-pressure water delivery
Saves 70-90% water compared to flood irrigation
Increases crop yield and allows precise fertilizer application
Core Benefits
Drip irrigation's targeted water delivery creates multiple advantages. Since water goes directly to plant roots rather than flooding the entire field, it solves key problems of traditional irrigation methods.
Major Advantages
Advantage | Mechanism | Impact |
|---|---|---|
Weed Reduction | Only plant root zones get water | Weeds can't grow in dry surrounding soil |
Soil Erosion Prevention | Low-pressure, drop-by-drop delivery | No surface runoff to wash away topsoil |
Water Conservation | Precise application, minimal evaporation | 70-90% less water than flood irrigation |
Higher Yields | Optimal soil moisture, reduced plant stress | 20-50% yield increase possible |
Fertigation | Fertilizers mixed with irrigation water | Precise nutrient delivery to roots |
Labour Reduction | Automated system, no manual watering | Reduces irrigation labour costs |
Question Context
Statement 1 (Weed Reduction) and Statement 3 (Soil Erosion Reduction) are correct advantages. The targeted water delivery naturally solves both problems without additional interventions.
Trap: Drip irrigation does NOT reduce soil salinity — it can actually increase it due to salt accumulation at wetted zone edges
Statement 2 confusion: Many students assume all irrigation improvements reduce salinity, but drip irrigation concentrates salts
Elimination trick: If you know Statement 2 is wrong, eliminate options (A) and (D), leaving (B) or (C)
Soil Salinity & Drip Irrigation
Indian Economy soil salinity
Why Drip Irrigation Can Increase Soil Salinity
Drip irrigation can increase soil salinity, not reduce it
Salt accumulation occurs at edges of wetted zones due to evaporation
This is a known disadvantage of drip irrigation systems
The Salinity Problem
Soil salinity refers to the concentration of dissolved salts in soil. While drip irrigation saves water and reduces weeds, it can actually worsen salinity problems in certain conditions.
How Salinity Increases
%%{init: {"flowchart": {"wrappingWidth": 460}}}%%
flowchart TD
s1["`**Water Application**
Drip irrigation delivers water to small root zones`"]
s2["`**Salt Movement**
Dissolved salts in water move with water flow`"]
s3["`**Evaporation**
Water evaporates from soil surface and plant leaves`"]
s4["`**Salt Concentration**
Salts remain behind and accumulate at wetted zone edges`"]
s5["`**Build-up**
Repeated cycles create high-salt zones around root areas`"]
s1 --> s2
s2 --> s3
s3 --> s4
s4 --> s5Key Factors
Poor quality water with high salt content worsens the problem
Inadequate drainage prevents salt leaching from root zones
High evaporation rates in hot, dry climates concentrate salts faster
Sandy soils allow better salt movement than clay soils
UPSC Context
Statement 2 in the question claims drip irrigation reduces soil salinity — this is incorrect. UPSC tested this common misconception. Many students assume all modern irrigation methods solve all problems, but drip irrigation has this specific disadvantage.
Major trap: Students assume 'modern = better in all ways' but drip irrigation increases salinity
Conceptual error: Confusing water conservation (benefit) with salinity reduction (not a benefit)
UPSC pattern: Testing disadvantages of otherwise beneficial technologies
Irrigation Methods: Comparison
Indian Economy
Major Irrigation Methods: Drip vs Sprinkler vs Flood
Flood irrigation uses most water but is cheapest to install
Drip irrigation has highest water efficiency but can increase soil salinity
Sprinkler irrigation balances water savings with uniform coverage
Overview
India uses multiple irrigation methods depending on crop type, water availability, and farmer resources. Each method has distinct advantages and limitations that UPSC often tests.
Method Comparison
Method | Water Efficiency | Installation Cost | Suitable For | Key Limitation |
|---|---|---|---|---|
Flood/Surface | Low (40-50%) | Very Low | Rice, wheat, large fields | High water waste, weed growth |
Sprinkler | Medium (70-80%) | Medium | Cereals, vegetables | Wind interference, some evaporation |
Drip/Micro | High (85-95%) | High | Fruits, cash crops | Soil salinity increase |
Subsurface Drip | Highest (95%+) | Very High | Permanent crops | Complex maintenance |
Irrigation Classification
# Irrigation Methods
## Surface/Gravity
- Basin
- Border
- Furrow
- Flood
## Pressurized
- Sprinkler
- Drip
- Micro-sprinkler
## Subsurface
- Subsurface drip
- Pitcher irrigationUPSC Testing Pattern
Water use efficiency: Drip > Sprinkler > Flood irrigation
Investment requirement: Drip > Sprinkler > Flood irrigation
Suitability: Drip for cash crops, sprinkler for field crops, flood for rice
Common trap: Assuming efficient methods solve all problems (salinity issue in drip)
Precision Agriculture in India
Indian Economy
Micro-Irrigation & Precision Agriculture: India's Push
Pradhan Mantri Krishi Sinchayee Yojana promotes micro-irrigation adoption
India has 2.77 million hectares under micro-irrigation (approximate)
Maharashtra, Karnataka, Gujarat lead in drip irrigation adoption
Government Push
India faces severe water stress with agriculture consuming 80% of available water. The government promotes micro-irrigation (drip + sprinkler) to boost water use efficiency and farm productivity.
Key Government Schemes
Scheme | Focus | Subsidy/Support | Target |
|---|---|---|---|
Pradhan Mantri Krishi Sinchayee Yojana | Micro-irrigation expansion | Up to 55% subsidy | More crop per drop |
National Mission on Micro-Irrigation | Drip & sprinkler systems | State-specific subsidies | Water use efficiency |
Climate Resilient Agriculture | Drought-proofing | Technology support | Adapt to climate change |
Indian Context Challenges
Small farm sizes make drip irrigation expensive per hectare for marginal farmers
Power subsidies for tube wells reduce incentive to save water through drip systems
Maintenance issues due to lack of technical knowledge in rural areas
Credit constraints prevent initial investment despite long-term benefits
Micro-irrigation Coverage
Map of India showing state-wise micro-irrigation coverage with Maharashtra, Karnataka, Gujarat highlighted as leaders
Western India leads micro-irrigation adoption due to water scarcity and cash crop cultivation
Trap: Don't confuse micro-irrigation (drip + sprinkler) with only drip irrigation in government schemes
Policy confusion: PMKSY covers broader irrigation, not just micro-irrigation — read questions carefully