Ch 6: Water

 

Chapter 6: Water

💧 Complete Chapter for PSTET Paper II (Social Studies)

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🎯 Learning Objectives for PSTET Aspirants

After completing this chapter, you will be able to:

• Analyze the distribution of water on Earth and understand the scarcity of usable freshwater

• Explain the water cycle and its processes with scientific accuracy

• Describe ocean relief features and their characteristics

• Differentiate between waves, tides, and ocean currents with their causes and effects

• Evaluate water as a resource for various human activities

• Identify causes and effects of water pollution and propose conservation methods

• Apply pedagogical strategies through models, discussions, and conservation projects

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6.1 Distribution of Water on Earth: Freshwater vs. Saline Water, the Scarcity of Usable Water

🌍 The Blue Planet

Earth is often called the "Blue Planet" because water covers approximately 71% of its surface. However, this abundance is misleading when it comes to usable water .

📊 Global Water Distribution

Water Type	Percentage	Volume (cubic km)	Location
Saline Water (Oceans)	97.5%	1,365,000,000	Oceans and seas
Freshwater	2.5%	35,000,000	Glaciers, ice caps, groundwater, lakes, rivers

❄️ Freshwater Breakdown

Of the 2.5% freshwater, its distribution is highly unequal:

text

                    TOTAL FRESHWATER (2.5%)
                           │
        ┌──────────────────┼──────────────────┐
        ▼                  ▼                  ▼
┌───────────────┐  ┌───────────────┐  ┌───────────────┐
│   GLACIERS    │  │  GROUNDWATER  │  │  SURFACE      │
│   & ICE CAPS  │  │               │  │  WATER        │
│     68.7%     │  │     30.1%     │  │     1.2%      │
└───────────────┘  └───────────────┘  └───────────────┘
                                              │
                              ┌───────────────┼───────────────┐
                              ▼               ▼               ▼
                       ┌───────────┐  ┌───────────┐  ┌───────────┐
                       │   LAKES   │  │  SOIL     │  │ RIVERS    │
                       │   0.26%   │  │ MOISTURE  │  │  0.006%   │
                       └───────────┘  │   0.05%   │  └───────────┘
                                      └───────────┘

Freshwater Source	Percentage of Total Freshwater	Availability
Glaciers and Ice Caps	68.7%	Frozen; inaccessible
Groundwater	30.1%	Deep; requires pumping
Lakes	0.26%	Accessible but unevenly distributed
Soil Moisture	0.05%	For plants only
Rivers	0.006%	Most accessible but tiny fraction
Atmosphere	0.04%	Water vapor

💧 The Scarcity Reality

Usable freshwater available for human consumption is extremely limited:

Fact	Implication
Only 0.3% of total water is readily usable	Most freshwater is locked in ice or deep underground
1.1 billion people lack access to safe drinking water	Water scarcity is a global crisis
2.4 billion lack adequate sanitation	Water pollution affects health
By 2025, 1.8 billion people will live in water-scarce regions	Growing crisis

🌊 Saline Water (Oceans and Seas)

Ocean	Area (million sq km)	Average Depth (m)	Deepest Point
Pacific Ocean	165.2	4,280	Mariana Trench (11,034 m)
Atlantic Ocean	106.5	3,646	Puerto Rico Trench (8,605 m)
Indian Ocean	70.6	3,741	Java Trench (7,725 m)
Southern Ocean	20.3	3,270	South Sandwich Trench (7,235 m)
Arctic Ocean	14.1	1,205	Eurasian Basin (5,450 m)

📝 PSTET Focus Point: The key takeaway is that although Earth has abundant water, usable freshwater is extremely scarce—only about 0.3% of total water. This understanding is fundamental for teaching water conservation.

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6.2 The Water Cycle / Hydrological Cycle: Processes of Evaporation, Condensation, Precipitation, and Collection

🔄 What is the Water Cycle?

The water cycle (hydrological cycle) is the continuous movement of water on, above, and below the Earth's surface. It is a closed system—no water is lost or gained; it simply changes form and location .

text

                    ┌─────────────────────────────────────┐
                    │         CONDENSATION                │
                    │    (Water vapor → Clouds)           │
                    └───────────────┬─────────────────────┘
                                    │
                                    │
                    ┌───────────────▼─────────────────────┐
                    │                                      │
              ┌─────┴─────┐                        ┌──────┴─────┐
              │           │                        │            │
              │  PRECIPITATION                     │ EVAPORATION│
              │  (Rain, snow, hail)                │ (Water →   │
              │           │                        │  vapor)    │
              └─────┬─────┘                        └──────┬─────┘
                    │                                      │
                    │                                      │
                    └───────────────┬──────────────────────┘
                                    │
                    ┌───────────────▼─────────────────────┐
                    │              COLLECTION              │
                    │  (Oceans, lakes, rivers, groundwater)│
                    └─────────────────────────────────────┘

💨 Key Processes of the Water Cycle

1. Evaporation

Aspect	Description
Definition	Process by which water changes from liquid to gas (water vapor)
Energy Source	Solar radiation (heat from the Sun)
Main Locations	Oceans (86% of evaporation), lakes, rivers, soil
Rate Factors	Temperature, humidity, wind speed, surface area

Transpiration: Plants release water vapor through their leaves. Combined evaporation and transpiration is called evapotranspiration .

2. Condensation

Aspect	Description
Definition	Process by which water vapor changes back to liquid water
Trigger	Air cools to its dew point (saturation temperature)
Requirements	Hygroscopic nuclei (dust, salt, smoke particles)
Results	Clouds, fog, dew

Cloud Formation: As warm, moist air rises, it expands and cools. When it reaches dew point, water vapor condenses around particles, forming tiny water droplets or ice crystals—clouds .

3. Precipitation

Aspect	Description
Definition	Water falling from clouds to Earth's surface
Trigger	Water droplets grow too heavy to remain suspended
Forms	Rain, snow, sleet, hail, drizzle
Global Distribution	Highest near equator, decreases toward poles

4. Collection (Runoff and Infiltration)

Process	Description	Destination
Runoff	Water flows over land surface	Rivers, lakes, oceans
Infiltration	Water soaks into ground	Groundwater, aquifers
Percolation	Water moves deeper through soil/rock	Deep groundwater

📊 Water Cycle by the Numbers

Process	Volume (cubic km/year)	Percentage
Evaporation from oceans	436,500	86%
Evaporation from land	71,000	14%
Total Evaporation	507,500	100%
Precipitation on oceans	398,000	78%
Precipitation on land	109,500	22%
Total Precipitation	507,500	100%
Runoff from land to oceans	38,500	-

💡 Key Insight: The water cycle is balanced—total evaporation equals total precipitation. However, distribution is uneven: oceans lose more water through evaporation than they gain from precipitation, while land gains more from precipitation than it loses through evaporation. The difference is made up by runoff from land to oceans .

⏱️ Residence Time of Water

Water spends varying amounts of time in different reservoirs:

Reservoir	Average Residence Time
Glaciers	20-100 years
Oceans	3,000 years
Groundwater (deep)	10,000+ years
Lakes	50-100 years
Rivers	2-6 months
Atmosphere	9-10 days
Soil moisture	2 weeks-1 year

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6.3 Oceans and Seas

6.3.1 Ocean Relief: Features of the Ocean Floor

The ocean floor is not flat—it has varied relief features similar to continents .

text

                    ┌─────────────────────────────────────┐
                    │         CONTINENTAL SHELF           │
                    │  (Gradual slope from shore)         │
                    └───────────┬─────────────────────────┘
                                │
                    ┌───────────▼─────────────────────────┐
                    │         CONTINENTAL SLOPE           │
                    │  (Steep drop)                       │
                    └───────────┬─────────────────────────┘
                                │
                    ┌───────────▼─────────────────────────┐
                    │         CONTINENTAL RISE            │
                    │  (Gentle slope to deep ocean)       │
                    └───────────┬─────────────────────────┘
                                │
        ┌───────────────────────┼───────────────────────┐
        ▼                       ▼                       ▼
┌───────────────┐      ┌───────────────┐      ┌───────────────┐
│   ABYSSAL     │      │  MID-OCEAN    │      │   DEEP-SEA    │
│    PLAIN      │      │    RIDGE      │      │   TRENCHES    │
│  (Flat deep)  │      │ (Underwater   │      │ (Deepest      │
└───────────────┘      │  mountains)   │      │  parts)       │
                       └───────────────┘      └───────────────┘

Major Ocean Floor Features

Feature	Description	Depth Range	Characteristics	Examples
Continental Shelf	Gently sloping submerged extension of continent	0-200 m	Richest fishing grounds; oil and gas deposits; sunlight reaches bottom	Broad off Siberia, narrow off South America
Continental Slope	Steep slope connecting shelf to deep ocean	200-3,000 m	Canyons cut by turbidity currents; boundary between continental and oceanic crust	-
Continental Rise	Gentle slope of accumulated sediments	3,000-4,000 m	Formed by sediment deposition from turbidity currents	-
Abyssal Plain	Flat, featureless deep ocean floor	3,000-6,000 m	Covered with fine sediments; most level places on Earth	Cover 40% of ocean floor
Mid-Ocean Ridge	Underwater mountain range	2,000-3,000 m above floor	Volcanic activity; new crust formed; longest mountain chain on Earth	Mid-Atlantic Ridge (16,000 km)
Deep-Sea Trenches	Deep, narrow depressions	6,000-11,000 m	Subduction zones; deepest parts of ocean	Mariana Trench (11,034 m)
Seamounts	Underwater volcanic mountains	Varies	May rise >1,000 m from ocean floor; flat-topped ones called guyots	Emperor Seamounts
Volcanic Islands	Seamounts rising above sea level	Above sea level	Formed by volcanic activity	Hawaii, Andaman Islands

Important Trenches

Trench	Ocean	Maximum Depth (m)
Mariana Trench	Pacific	11,034
Tonga Trench	Pacific	10,882
Philippine Trench	Pacific	10,540
Kuril-Kamchatka Trench	Pacific	10,542
Puerto Rico Trench	Atlantic	8,605
Java Trench	Indian	7,725

Ocean Floor Sediments

Type	Composition	Location
Terrigenous	Eroded from land (sand, mud)	Near continents
Biogenous	Shells and skeletons of marine organisms	Deep ocean floors
Hydrogenous	Precipitated from seawater (manganese nodules)	Abyssal plains
Cosmogenous	Space dust and meteorite debris	Rare; everywhere

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6.3.2 Ocean Water Movements: Waves, Tides, and Ocean Currents

Ocean water is in constant motion, driven by various forces .

🌊 Waves

Aspect	Description
Definition	Oscillatory movement of water surface
Energy Source	Wind (mostly)
Motion	Water particles move in circular orbits; energy moves forward, not water itself
Parts	Crest (highest point), Trough (lowest point), Height (crest to trough), Length (crest to crest)

Types of Waves

Type	Cause	Characteristics
Wind Waves	Local wind	Irregular; short wavelength
Swells	Distant storms	Regular; long wavelength
Tsunamis	Earthquakes, volcanic eruptions	Very long wavelength (100-200 km); speed up to 800 km/h; destructive near shore
Tidal Waves	Gravitational pull of moon/sun	Actually tides, not true waves

Wave Behavior Near Shore:

• Wave speed decreases in shallow water

• Wavelength decreases

• Wave height increases

• Wave becomes unstable and breaks (surf)

🌕 Tides

Tides are the periodic rise and fall of sea level caused primarily by the gravitational pull of the Moon and, to a lesser extent, the Sun.

Cause of Tides

text

                    ┌─────────────────────────────────────┐
                    │         GRAVITATIONAL FORCES        │
                    └─────────────────────────────────────┘
                                    │
              ┌─────────────────────┼─────────────────────┐
              ▼                     ▼                     ▼
    ┌───────────────┐      ┌───────────────┐      ┌───────────────┐
    │   MOON'S      │      │   SUN'S       │      │  CENTRIFUGAL  │
    │  GRAVITY      │      │  GRAVITY      │      │    FORCE      │
    │ (Primary)     │      │ (Secondary)   │      │ (Opposite to  │
    └───────────────┘      └───────────────┘      │  gravity)     │
                                                   └───────────────┘

Tidal Bulges: Two bulges occur—one facing the moon (due to gravity) and one opposite the moon (due to centrifugal force). As Earth rotates, different locations pass through these bulges, experiencing two high tides and two low tides approximately every 24 hours 50 minutes .

Types of Tides

Type	Frequency	Characteristics
Spring Tides	Twice monthly (full and new moon)	Sun and moon aligned; highest high tides; lowest low tides
Neap Tides	Twice monthly (first and last quarter moon)	Sun and moon at right angles; least tidal range

text

                    SPRING TIDES                    NEAP TIDES
              ┌─────────────────────┐         ┌─────────────────────┐
              │   Sun  Moon  Earth  │         │   Sun               │
              │      ●───●────●     │         │      ●              │
              │      │              │         │       \             │
              │      └──Gravity───► │         │        \            │
              │    (Aligned)        │         │         ● Earth     │
              │                     │         │        /            │
              │  High tides VERY    │         │       /             │
              │  HIGH; Low tides    │         │      ● Moon         │
              │  VERY LOW           │         │   (At right angles) │
              │                     │         │                     │
              │  Tidal range:       │         │  Tidal range:       │
              │  MAXIMUM            │         │  MINIMUM            │
              └─────────────────────┘         └─────────────────────┘

Importance of Tides

Importance	Description
Navigation	Help ships enter shallow ports during high tide
Fishing	Fish gather during tides; traditional knowledge used
Tidal Energy	Renewable energy source (tidal power plants)
Coastal Ecosystems	Intertidal zones support unique biodiversity
Waste Disposal	Flush out pollutants from estuaries

🌊 Ocean Currents

Ocean currents are continuous, directed movements of ocean water flowing horizontally .

Causes of Ocean Currents

Cause	Type	Description
Wind	Surface currents	Planetary winds (trade winds, westerlies) drive surface currents
Earth's Rotation	Coriolis effect	Deflects currents to right in N. Hemisphere, left in S. Hemisphere
Temperature	Thermohaline circulation	Cold, dense water sinks; warm water rises
Salinity	Thermohaline circulation	Higher salinity = denser water = sinks
Landmasses	Obstruction	Continents deflect currents

Classification of Ocean Currents

Based on Temperature:

Type	Temperature	Direction	Examples
Warm Currents	Warmer than surrounding water	From equator toward poles	Gulf Stream, Kuroshio, Brazil Current
Cold Currents	Colder than surrounding water	From poles toward equator	Labrador, Canary, Benguela, Peru (Humboldt)

Based on Depth:

Type	Depth	Cause
Surface Currents	Top 400 m	Wind-driven
Deep Water Currents	Below 400 m	Density differences (temperature, salinity)

Major Ocean Currents

text

                    NORTH AMERICA
                          │
        ┌─────────────────┼─────────────────┐
        │                 │                 │
        ▼                 ▼                 ▼
┌───────────────┐  ┌───────────────┐  ┌───────────────┐
│   Labrador    │  │  Gulf Stream  │  │ Canary Current│
│   Cold        │  │  Warm         │  │ Cold          │
└───────────────┘  └───────────────┘  └───────────────┘

Current	Ocean	Type	Destination/Origin
Gulf Stream	Atlantic	Warm	From Gulf of Mexico to NW Europe
North Atlantic Drift	Atlantic	Warm	Extension of Gulf Stream; warms Europe
Canary Current	Atlantic	Cold	Off NW Africa; flows south
Benguela Current	Atlantic	Cold	Off SW Africa; flows north
Labrador Current	Atlantic	Cold	From Arctic to NE North America
Brazil Current	Atlantic	Warm	South along Brazil coast
Kuroshio Current	Pacific	Warm	East of Japan; "Pacific Gulf Stream"
Oyashio Current	Pacific	Cold	From Arctic to NE Japan
California Current	Pacific	Cold	West coast of North America
Peru (Humboldt) Current	Pacific	Cold	West coast of South America
East Australian Current	Pacific	Warm	East coast of Australia
Agulhas Current	Indian	Warm	East coast of Africa
West Australian Current	Indian	Cold	West coast of Australia

Effects of Ocean Currents

Effect	Description	Examples
Climate Modification	Warm currents raise temperatures; cold currents lower them	Gulf Stream warms NW Europe; Labrador Current chills NE Canada
Fog Formation	Cold currents cool warm, moist air → fog	Grand Banks fog (Labrador Current meets Gulf Stream)
Desert Formation	Cold currents stabilize air, reducing rainfall	Atacama Desert (Peru Current); Namib Desert (Benguela Current)
Rainfall Patterns	Warm currents increase evaporation → rainfall	Eastern coasts of continents (warm currents)
Marine Life	Currents distribute nutrients and larvae	Upwelling areas (cold currents) rich in fish
Navigation	Currents affect ship travel times	Following currents saves fuel

Thermohaline Circulation (Global Conveyor Belt)

The global conveyor belt is a deep-ocean circulation system driven by temperature and salinity differences :

text

    ┌─────────────────────────────────────────────────────────┐
    │                                                          │
    │   North Atlantic ──► Deep water forms ──► Flows south   │
    │        │                                                │
    │        ▼                                                │
    │   Southern Ocean ──► Indian Ocean ──► Pacific Ocean     │
    │        │                                                │
    │        ▼                                                │
    │   Upwelling ──► Warm surface return flow                │
    │                                                          │
    │   Complete cycle takes ~1,000 years                      │
    └─────────────────────────────────────────────────────────┘

Importance:

• Distributes heat globally

• Brings nutrients to surface (upwelling)

• Regulates climate

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6.4 Water as a Resource: Importance for Drinking, Irrigation, Industry, and Transportation

💧 The Many Uses of Water

Water is essential for virtually all human activities .

1. Drinking and Domestic Use

Use	Percentage of Global Water Use	Importance
Drinking	Small fraction	Essential for survival; humans need 2-3 liters/day
Cooking	-	Food preparation
Sanitation	-	Hygiene, disease prevention
Cleaning	-	Household and personal cleanliness

Global Access:

• 71% of global population has access to safely managed drinking water

• 2.2 billion people lack safely managed drinking water

• 3.6 billion lack safely managed sanitation

2. Irrigation (Agriculture)

Aspect	Detail
Global Water Use	70% of all freshwater withdrawals
In India	80-90% of freshwater used for agriculture
Purpose	Crop production; livestock
Methods	Canal irrigation, wells, drip irrigation, sprinklers

Water-Intensive Crops:

• Rice: 2,500-5,000 liters per kg

• Wheat: 1,500-2,000 liters per kg

• Sugarcane: 1,500-2,500 liters per liter of juice

• Cotton: 10,000-20,000 liters per kg

Punjab Context:

• Punjab uses 85% of its water for agriculture

• Paddy (rice) is the most water-intensive crop

• Groundwater depletion is a serious concern—water table dropping 0.5-1.0 m per year in many areas

3. Industry

Use	Percentage of Global Water Use	Examples
Manufacturing	19%	Processing, cooling, washing
Energy Production	-	Thermal power plant cooling; hydropower
Mining	-	Mineral processing
Construction	-	Mixing concrete

Industrial Uses:

• Cooling: Thermal and nuclear power plants require huge amounts

• Processing: Food, beverage, textile, paper industries

• Cleaning: Washing raw materials and products

• Solvent: Chemical industries

• Transport: Slurry pipelines

4. Transportation

Mode	Description	Importance
Inland Waterways	Rivers, canals, lakes	Low-cost transport; fuel-efficient
Ocean Shipping	Seas and oceans	90% of global trade by volume
Ports and Harbors	Coastal infrastructure	Trade hubs

India's Water Transport:

• Inland waterways: 14,500 km navigable; National Waterways (Ganga, Brahmaputra)

• Major ports: 12 major ports (Mumbai, Chennai, Kolkata, Kandla, etc.)

• Minor ports: 200+ along coastline

5. Other Uses

Use	Description
Recreation	Swimming, boating, fishing
Hydropower	Electricity generation from flowing water
Ecosystem Support	Maintains wetlands, rivers, lakes
Cultural/Religious	Rituals, pilgrimages (Ganga, Yamuna)

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6.5 Water Pollution and Conservation: Causes, Effects, and Methods

🚯 Water Pollution

Water pollution is the contamination of water bodies by harmful substances, making water unsafe for human use and damaging aquatic ecosystems .

Major Causes of Water Pollution

Source	Types	Examples
Industrial Waste	Chemicals, heavy metals, toxins	Factories discharge untreated effluents
Agricultural Runoff	Fertilizers, pesticides, animal waste	Nitrogen, phosphorus cause eutrophication
Domestic Sewage	Human waste, detergents, pathogens	Untreated sewage into rivers
Oil Spills	Crude oil, petroleum products	Tanker accidents; offshore drilling
Plastic Waste	Non-biodegradable debris	Microplastics in oceans
Thermal Pollution	Heated water from power plants	Reduces oxygen; harms aquatic life
Mining Activities	Acid mine drainage, heavy metals	Contaminates groundwater and rivers

Types of Water Pollutants:

Pollutant Type	Examples	Effects
Pathogens	Bacteria, viruses, parasites	Waterborne diseases (cholera, typhoid)
Organic Matter	Sewage, food waste	Oxygen depletion; fish kills
Nutrients	Nitrogen, phosphorus	Eutrophication; algal blooms
Chemicals	Pesticides, industrial chemicals	Toxicity; bioaccumulation
Heavy Metals	Lead, mercury, arsenic	Poisoning; long-term health effects
Sediments	Soil erosion	Turbidity; smothers aquatic life
Plastics	Microplastics, macroplastics	Ingestion by marine life; ecosystem damage

Effects of Water Pollution

Effect	Description
Human Health	Waterborne diseases (diarrhea, cholera, typhoid); 1.8 million deaths annually
Aquatic Life	Fish kills; habitat destruction; biodiversity loss
Eutrophication	Algal blooms; oxygen depletion; dead zones (e.g., Gulf of Mexico)
Economic Impact	Fishing industry losses; tourism decline; water treatment costs
Ecosystem Disruption	Food chain contamination; species extinction

🌱 Water Conservation

Water conservation is the practice of using water efficiently to reduce unnecessary water usage .

Why Conserve Water?

Reason	Explanation
Scarcity	Freshwater is limited (only 0.3% usable)
Growing Demand	Population growth, agriculture, industry increase demand
Groundwater Depletion	Over-extraction lowers water tables
Climate Change	Alters rainfall patterns; increases droughts
Ecosystem Protection	Maintains rivers, lakes, wetlands

Methods of Water Conservation

1. Rainwater Harvesting

Rainwater harvesting is the collection and storage of rainwater for reuse.

text

                    ┌─────────────────────────────────────┐
                    │           RAINWATER                  │
                    │           HARVESTING                  │
                    └─────────────────────────────────────┘
                                    │
              ┌─────────────────────┼─────────────────────┐
              ▼                     ▼                     ▼
    ┌───────────────┐      ┌───────────────┐      ┌───────────────┐
    │  ROOFTOP      │      │  SURFACE      │      │  RECHARGE     │
    │  COLLECTION   │      │  RUNOFF       │      │  STRUCTURES   │
    ├───────────────┤      │  COLLECTION   │      ├───────────────┤
    │ • Gutters     │      ├───────────────┤      │ • Recharge    │
    │ • Downpipes   │      │ • Ponds       │      │   wells       │
    │ • Storage     │      │ • Tanks       │      │ • Percolation │
    │   tanks       │      │ • Check dams  │      │   pits        │
    └───────────────┘      └───────────────┘      └───────────────┘

Benefits of Rainwater Harvesting:

• Reduces runoff and flooding

• Recharges groundwater

• Provides water during dry periods

• Reduces demand on municipal supplies

• Improves water quality (dilutes pollutants)

Traditional Methods in India:

Method	Region	Description
Kunds	Rajasthan	Covered tanks for rainwater
Johads	Rajasthan	Earthen check dams
Khadins	Rajasthan	Embankments to capture runoff
Ahar-Pynes	Bihar	Channels and reservoirs
Eri (Tanks)	Tamil Nadu	Village ponds for irrigation
Kuls	Himachal	Water channels from streams
Zabo	Nagaland	Integrated systems for rainwater

2. Water-Efficient Agriculture

Method	Description	Water Savings
Drip Irrigation	Water delivered directly to plant roots	30-70% less than flood irrigation
Sprinkler Irrigation	Water sprayed like rain	30-50% less than flood irrigation
Mulching	Cover soil to reduce evaporation	10-30% savings
Crop Selection	Grow less water-intensive crops	Significant
Furrow Irrigation	Water in channels between rows	More efficient than flood
Laser Land Leveling	Precise field leveling	20-30% water savings

3. Domestic Water Conservation

Method	Water Saved (per person per day)
Fix leaky taps	10-50 liters
Turn off tap while brushing	10-15 liters
Use bucket instead of shower	50-100 liters
Dual-flush toilets	20-40 liters
Water-efficient appliances	30-50 liters
Reuse RO wastewater	10-20 liters

4. Industrial Water Conservation

Method	Description
Recycling	Treat and reuse water in processes
Cooling Towers	Recycle cooling water
Dry Cooling	Air cooling instead of water
Water Audits	Identify and fix leaks
Efficient Processes	Modify manufacturing to use less water

5. Community and Government Initiatives

Initiative	Description
Watershed Development	Integrated management of land and water
Check Dams	Small dams to store monsoon runoff
Pond Renovation	Cleaning and deepening village ponds
Groundwater Regulation	Control on borewell drilling
Water Pricing	Incentivize conservation
Public Awareness	Campaigns, school programs

📊 Water Conservation Success Stories in India

Location	Initiative	Result
Ralegan Siddhi (Maharashtra)	Watershed development, rainwater harvesting	From drought-prone to water-sufficient
Hiware Bazar (Maharashtra)	Water budgeting, contour trenches	Groundwater levels rose; prosperity increased
Arvari River (Rajasthan)	Community check dams	River revived after 60 years of drying
Sukhomajri (Haryana)	Watershed management	Reduced erosion; increased water availability
Tamil Nadu	Mandatory rooftop rainwater harvesting	Groundwater levels stabilized

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6.6 Pedagogical Focus: Creating Models, Discussing Local Issues, and Promoting Conservation

🧒 Understanding the Learner (Classes VI-VIII)

Upper primary students:

• Are concrete thinkers; learn through hands-on activities

• Can understand cause-and-effect relationships

• Develop environmental awareness and sense of responsibility

• Can participate in community projects

🌊 Creating Models of the Water Cycle

Simple Water Cycle Model (In a Bottle)

Step	Instructions
Materials	Clear plastic bottle, soil, small plant, water, cling film, elastic band, ice cubes
Step 1	Cut bottle in half; keep top and bottom
Step 2	Place soil and small plant in bottom; add water
Step 3	Invert top portion like a funnel into bottom
Step 4	Cover top with cling film; secure with band
Step 5	Place ice cubes on cling film
Step 6	Place in sunny spot
Observation	Water evaporates, condenses on cool film, "rains" back into soil

3D Water Cycle Model

Component	Material	Representation
Sun	Yellow ball/paper	Energy source
Ocean	Blue paper/water	Water body
Evaporation	Arrows (blue→white)	Water rising
Clouds	Cotton balls	Condensation
Precipitation	Blue beads/threads	Rain falling
Mountains	Brown paper/ clay	Landforms
River	Blue ribbon	Runoff
Groundwater	Blue under brown layer	Infiltration

💬 Discussing Local Water Issues

Inquiry-Based Discussion Framework

Question	Purpose
"Where does our drinking water come from?"	Identify local water sources
"Is water easily available throughout the year?"	Understand seasonal variation
"Have you ever faced water shortage?"	Personal connection
"What happens to dirty water from our homes?"	Wastewater awareness
"Are the rivers/ponds in our area clean?"	Local pollution awareness
"Why do farmers need so much water?"	Agricultural water use
"How can we use less water?"	Conservation thinking

Local Water Issues to Discuss

Issue Type	Examples
Groundwater Depletion	Falling water table in Punjab; deep borewells
Canal Water Distribution	Sharing disputes; tail-end deprivation
River Pollution	Sutlej, Beas pollution; industrial waste
Stubble Burning and Water	Link to groundwater?
Flooding vs. Drought	Seasonal extremes
Water Quality	Arsenic, fluoride, salinity

🏫 Promoting Water Conservation in Schools

School-Wide Activities

Activity	Description	Impact
Water Audit	Students measure water usage in school	Data-driven awareness
Leak Detection	Check all taps and pipes for leaks	Immediate water savings
Rainwater Harvesting Installation	Set up system on school roof	Long-term solution; learning opportunity
Poster Campaign	Create awareness posters	Peer education
Water Pledge	Students commit to conservation	Behavioral change
Competitions	Essay, drawing, model-making	Engagement

Classroom Activities

Activity 1: Water Diary

Day	Activity	Water Used (liters)
Morning	Brushing teeth (tap running)	15
Morning	Brushing teeth (tap off)	1
	Shower (10 min)	100
	Shower (5 min)	50
	Flush (old toilet)	15
	Flush (dual-flush, low)	3

Discussion: Compare totals; identify savings

Activity 2: Water Footprint Calculation

Item	Water Required	Calculation
1 kg rice	3,000 liters	3,000 × __ kg = __
1 kg wheat	1,500 liters	1,500 × __ kg = __
1 kg sugar	1,500 liters	1,500 × __ kg = __
1 cup tea	30 liters	30 × __ cups = __
1 kg cotton (shirt)	10,000 liters	10,000 × __ kg = __

Activity 3: Clean Water Experiment

Step	Instructions
Materials	2-liter bottle, sand, gravel, charcoal, cloth, dirty water
Step 1	Cut bottle; invert top into bottom
Step 2	Layer: cloth, charcoal, sand, gravel (from bottom to top)
Step 3	Pour dirty water through
Step 4	Observe filtered water
Discussion	How does this relate to groundwater recharge?

Activity 4: Save Water Challenge

Challenge	Duration	Tracking
5-minute shower	1 week	Timer; record
Turn off tap while brushing	1 week	Self-monitoring
Report leaks at home	1 week	List found
Reuse RO/reverse osmosis water for plants	1 week	Volume collected
Bucket instead of hose for car washing	1 week	Compare usage

📝 Sample Lesson Plan: "Water Conservation in Our Community"

Lesson Component	Description
Topic	Understanding and addressing local water issues
Class	VII-VIII
Duration	3 class periods + fieldwork
Learning Objectives	Students will: (1) Identify local water sources (2) Assess water quality/availability (3) Propose conservation measures
Day 1: Investigation	Discuss local water sources; map them; identify issues
Day 2: Fieldwork	Visit local water body/well; observe; interview residents
Day 3: Analysis and Action	Analyze findings; design awareness campaign; propose solutions
Assessment	Project report; presentation; campaign materials

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📝 Chapter Summary: Key Points for PSTET Revision

🔑 Water Distribution

Type	Percentage
Saline water	97.5%
Freshwater	2.5%
Usable freshwater	0.3%

🔑 Water Cycle Processes

1. Evaporation: Liquid → gas (solar energy)

2. Condensation: Gas → liquid (cooling)

3. Precipitation: Water falls (rain, snow)

4. Collection: Runoff, infiltration

🔑 Ocean Relief Features

Feature	Depth	Characteristics
Continental Shelf	0-200 m	Fishing, oil/gas
Continental Slope	200-3,000 m	Steep drop
Abyssal Plain	3,000-6,000 m	Flat deep
Trenches	6,000-11,000 m	Deepest parts

🔑 Ocean Movements

Movement	Cause	Characteristics
Waves	Wind	Oscillatory
Tides	Moon/Sun gravity	Periodic rise/fall
Currents	Wind, temperature, salinity	Continuous flow

🔑 Water Uses

• Drinking (essential)

• Irrigation (70% global, 80-90% India)

• Industry (19% global)

• Transportation (inland waterways, oceans)

🔑 Water Pollution and Conservation

Pollution Sources	Conservation Methods
Industrial waste	Rainwater harvesting
Agricultural runoff	Drip irrigation
Domestic sewage	Water-efficient practices
Oil spills	Recycling and reuse

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📝 Practice Questions for PSTET Preparation

Multiple Choice Questions

1. What percentage of Earth's water is freshwater?
   a) 97.5%
   b) 2.5%
   c) 0.3%
   d) 30.1%

2. Which process in the water cycle involves water changing from liquid to gas?
   a) Condensation
   b) Precipitation
   c) Evaporation
   d) Infiltration

3. The deepest part of the ocean is:
   a) Continental shelf
   b) Abyssal plain
   c) Mariana Trench
   d) Mid-ocean ridge

4. Spring tides occur during:
   a) First quarter moon
   b) Full moon and new moon
   c) Last quarter moon
   d) All moon phases

5. Which ocean current warms the northwest coast of Europe?
   a) Labrador Current
   b) Canary Current
   c) Gulf Stream
   d) Benguela Current

6. What percentage of freshwater in India is used for agriculture?
   a) 50-60%
   b) 70-75%
   c) 80-90%
   d) 95-98%

7. Which of the following is NOT a method of water conservation?
   a) Rainwater harvesting
   b) Drip irrigation
   c) Flood irrigation
   d) Mulching

8. The Coriolis effect causes ocean currents to deflect:
   a) Right in both hemispheres
   b) Left in both hemispheres
   c) Right in Northern Hemisphere, left in Southern Hemisphere
   d) Left in Northern Hemisphere, right in Southern Hemisphere

9. Eutrophication in water bodies is caused by excess:
   a) Oxygen
   b) Nitrogen and phosphorus
   c) Carbon dioxide
   d) Salt

10. The standard meridian of India (82°30'E) passes through:
    a) Delhi
    b) Mumbai
    c) Mirzapur
    d) Chennai

Short Answer Questions

11. Explain why usable freshwater is scarce despite 71% of Earth being covered with water.

12. Describe the four main processes of the water cycle with examples.

13. Differentiate between spring tides and neap tides.

14. What are the causes and effects of ocean currents?

15. List any five methods of water conservation that can be implemented at home.

Long Answer Questions

16. Explain the distribution of water on Earth with the help of a diagram. Why is water conservation necessary?

17. Describe the features of the ocean floor with a labeled diagram.

18. Discuss the causes and effects of water pollution. Suggest measures to control it.

19. As a teacher, how would you create awareness about water conservation among students? Describe any three activities.

20. Analyze the importance of monsoon for India's water resources. How does Punjab's agriculture depend on monsoon and groundwater?

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✅ Chapter Completion Checklist

Before moving to Chapter 7, ensure you can:

• Explain global water distribution with percentages

• Draw and explain the water cycle

• Label ocean floor features on a diagram

• Differentiate between waves, tides, and currents

• Name major warm and cold currents

• List four major uses of water with examples

• Identify five causes of water pollution

• Describe five water conservation methods

• Explain rainwater harvesting

• Plan a water cycle model activity

• Design a local water issues discussion

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🔗 Online Resources for Further Learning

Resource	Description	Link/How to Find
NASA Water Cycle	Interactive water cycle resources	gpm.nasa.gov/education
Central Ground Water Board	Groundwater data, India	cgwb.gov.in
National Water Mission	Government water conservation	nwm.gov.in
UN Water	Global water issues	unwater.org
NCERT Geography	Class VI, VII, VIII resources	ncert.nic.in
Rainwater Harvesting Manual	Practical guide	cseindia.org

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🎓 Prepared for PSTET Aspirants

This chapter provides comprehensive coverage of "Water" as per PSTET Paper II syllabus. Water is life—understand its distribution, movements, and conservation thoroughly. For Punjab-specific context, pay special attention to groundwater depletion and agricultural water use. Use the activities to make learning engaging and impactful for your future students!

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