The Earth- Environment
📚 Topic Overview: The Earth – Environment
This topic explains how our planet functions through its major spheres—land, water, air and life.
It covers environmental components, Earth’s interior, atmosphere, biosphere, pollution, disasters
and Andhra Pradesh–specific environmental highlights. Concepts are aligned across classes III–X.
1. The Earth Environment
Concept / Theory
The environment is everything that surrounds us—air, water, land, plants, animals and humans.
The Earth environment operates through four major interlinked systems:
- Lithosphere: land/solid part of Earth
- Hydrosphere: all forms of water
- Atmosphere: air/gases surrounding Earth
- Biosphere: life-supporting zone
Important Notes
- Environment supports life through balance among air, water and land.
- Human activities can disturb this balance (deforestation, pollution, overuse of resources).
- Climate, weather and seasons depend on interactions between the four spheres.
🧠 Memory Key:
Remember the four spheres with the code
“LABH” → Lithosphere, Atmosphere, Biosphere, Hydrosphere.
Remember the four spheres with the code
“LABH” → Lithosphere, Atmosphere, Biosphere, Hydrosphere.
🔍 Example / Application:
A river ecosystem depends on: land for soil (lithosphere), water flow (hydrosphere), fishes and plants (biosphere),
and temperature/evaporation (atmosphere).
A river ecosystem depends on: land for soil (lithosphere), water flow (hydrosphere), fishes and plants (biosphere),
and temperature/evaporation (atmosphere).
📝 Exam Tip:
Questions often ask: “Which sphere does snow belong to?” → Hydrosphere (solid form).
Questions often ask: “Which sphere does snow belong to?” → Hydrosphere (solid form).
2. Components of the Earth
Core Concepts
- The Earth is made up of four major components: land, water, air and life.
- These components interact continuously.
- The Sun provides the primary energy for Earth’s systems.
Comparison Table
| Component | Meaning | Main Features |
|---|---|---|
| Lithosphere | Solid rocky outer layer | Mountains, plateaus, plains, soil |
| Hydrosphere | All forms of water | Oceans, rivers, lakes, glaciers, groundwater |
| Atmosphere | Air envelope | Weather, clouds, winds, gases |
| Biosphere | Life zone | Plants, animals, humans, microbes |
🧠 Short Formula:
Earth = Land + Water + Air + Life.
Earth = Land + Water + Air + Life.
🔍 Example:
Sea breeze and land breeze occur due to differential heating of land (lithosphere) and sea (hydrosphere),
creating wind (atmosphere) that affects coastal living beings (biosphere).
Sea breeze and land breeze occur due to differential heating of land (lithosphere) and sea (hydrosphere),
creating wind (atmosphere) that affects coastal living beings (biosphere).
📝 Exam Tip:
Features like coral reefs, deltas, dunes, icebergs belong to specific components—practice quick identification.
Features like coral reefs, deltas, dunes, icebergs belong to specific components—practice quick identification.
3. Environment Components: Living, Non-living, Natural & Man-made
Biotic vs Abiotic
| Type | Meaning | Examples |
|---|---|---|
| Biotic | Living things | Plants, animals, humans, microbes |
| Abiotic | Non-living things | Air, water, soil, rocks, sunlight |
Natural vs Man-made Environment
| Type | Meaning | Examples |
|---|---|---|
| Natural | Created by nature | Forests, mountains, rivers, seas |
| Man-made | Created/modified by humans | Cities, roads, dams, factories |
🧠 Keyword Trick:
Anything that can “grow or reproduce” → Biotic.
Anything “built by humans” → Man-made.
Anything that can “grow or reproduce” → Biotic.
Anything “built by humans” → Man-made.
🔍 Example:
A school campus has trees (natural–biotic), buildings (man-made), soil (abiotic), students (biotic).
A school campus has trees (natural–biotic), buildings (man-made), soil (abiotic), students (biotic).
📝 Exam Tip:
Often asked: “Classify the following into natural/man-made.”
Often asked: “Classify the following into natural/man-made.”
4. Interior of the Earth
Layers of the Earth
| Layer | Nature | Key Points |
|---|---|---|
| Crust | Solid outermost layer | Where we live; contains soil & minerals |
| Mantle | Hot semi-solid rock | Responsible for plate movement |
| Outer Core | Liquid iron & nickel | Creates magnetic field |
| Inner Core | Solid metal sphere | Hottest region |
How We Know?
- Through seismic waves recorded by a seismograph.
- By studying volcanic rocks and deep mines.
Effects of Interior
- Earthquakes
- Volcanic eruptions
- Mountain formation
- Mineral formation
🧠 Memory Code:
C → M → OC → IC (Crust, Mantle, Outer Core, Inner Core)
C → M → OC → IC (Crust, Mantle, Outer Core, Inner Core)
🔍 Example:
Plate movement in the mantle caused the Himalayas to rise.
Plate movement in the mantle caused the Himalayas to rise.
📝 Tip:
Questions often ask “Which layer is thickest?” → Mantle.
Questions often ask “Which layer is thickest?” → Mantle.
5. Earth’s Atmosphere
Composition
- Nitrogen – 78%
- Oxygen – 21%
- Other gases – 1%
- Dust + Water vapour
Atmospheric Layers
| Layer | Height | Main Features |
|---|---|---|
| Troposphere | 0–12 km | Weather occurs here |
| Stratosphere | 12–50 km | Contains ozone layer |
| Mesosphere | 50–80 km | Meteors burn |
| Thermosphere | Above 80 km | Auroras, satellites |
| Exosphere | Outer | Very thin gases |
Instruments
- Thermometer → Temperature
- Barometer → Pressure
- Anemometer → Wind speed
- Rain gauge → Rainfall
🧠 Shortcut:
“The Smart Man Talks Easily” → Troposphere, Stratosphere, Mesosphere, Thermosphere, Exosphere.
“The Smart Man Talks Easily” → Troposphere, Stratosphere, Mesosphere, Thermosphere, Exosphere.
🔍 Example:
Airplanes usually fly in the lower stratosphere because it is stable and cloud-free.
Airplanes usually fly in the lower stratosphere because it is stable and cloud-free.
📝 Tip:
Ozone layer is ALWAYS in the stratosphere—very frequently tested.
Ozone layer is ALWAYS in the stratosphere—very frequently tested.
6. Biosphere
Meaning
The biosphere is the narrow zone where life exists—on land, in water and air.
Parts of Biosphere
- Producers – plants
- Consumers – animals, humans
- Decomposers – bacteria, fungi
Ecosystem
- Interaction between living and non-living components
- Examples: pond, forest, grassland, ocean
🧠 Memory Tip:
Every ecosystem = Producers + Consumers + Decomposers + Abiotic factors.
Every ecosystem = Producers + Consumers + Decomposers + Abiotic factors.
🔍 Example:
In a forest, trees (producers), deer (consumers), and fungi (decomposers) form the food chain.
In a forest, trees (producers), deer (consumers), and fungi (decomposers) form the food chain.
📝 Tip:
“Food chain” always flows from plants → herbivores → carnivores → decomposers.
“Food chain” always flows from plants → herbivores → carnivores → decomposers.
7. Pollution: Types, Causes & Conservation
Meaning
Pollution is the introduction of harmful substances or energy into the environment.
Types of Pollution
| Type | Main Sources | Effects |
|---|---|---|
| Air Pollution | Vehicles, industries, burning fuel | Respiratory problems, smog |
| Water Pollution | Sewage, chemicals, waste | Unsafe water, loss of aquatic life |
| Soil Pollution | Pesticides, fertilizers, waste | Reduced fertility |
| Noise Pollution | Traffic, loudspeakers | Hearing issues, stress |
Control Measures
- Use public transport
- Treat sewage & industrial waste
- Use organic farming
- Plant trees
- Follow “Reduce, Reuse, Recycle”
🧠 Memory Code:
3R + T → Reduce, Reuse, Recycle + Treat waste
3R + T → Reduce, Reuse, Recycle + Treat waste
🔍 Example:
A water treatment plant reduces water pollution by purifying waste water.
A water treatment plant reduces water pollution by purifying waste water.
📝 Tip:
Match each pollution type to “source + control measure.”
Match each pollution type to “source + control measure.”
8. Disasters: Types, Causes & Management
Types
| Type | Examples |
|---|---|
| Natural | Cyclones, floods, droughts, earthquakes |
| Human-made | Fires, chemical spills, industrial accidents |
Disaster Management Steps
- Mitigation
- Preparedness
- Response
- Recovery
Important Organizations
- NDMA — National Disaster Management
- NDRF — Rescue & response force
- IMD — Weather forecasting
🧠 Formula:
MPRR → Mitigation → Preparedness → Response → Recovery
MPRR → Mitigation → Preparedness → Response → Recovery
🔍 Example:
Setting up cyclone shelters in coastal areas reduces loss of life.
Setting up cyclone shelters in coastal areas reduces loss of life.
📝 Tip:
Most questions test classification (natural vs human-made).
Most questions test classification (natural vs human-made).
9. Andhra Pradesh – Environment & Disaster Highlights
Environmental Features
- Long coastline — vulnerable to cyclones
- Large wetlands like Kolleru Lake
- Eastern Ghats forest areas
Major Cyclones
- Hudhud (2014) — Severe damage in Visakhapatnam
- Titli (2018) — Impact on Srikakulam
Major Rivers & Flood Zones
- Godavari — frequent floods in Konaseema
- Krishna — flooding near Vijayawada
State Disaster Management
- APSDMA issues alerts and warnings
- Evacuation plans for coastal districts
- Cyclone shelters and disaster drills
Diviseema Disaster (1977) – Cyclone & Storm Surge (Not a Tsunami)
The severe cyclone of 19 November 1977 struck the coast of Andhra Pradesh and caused massive destruction in the Diviseema region of Krishna district. Although people often call it a “tsunami,” it was actually a cyclone-generated storm surge (tidal wave) and NOT a tsunami.
| Disaster Feature | Details |
|---|---|
| Type of Event |
|
| Most Affected Area |
|
| Impact |
|
Government Response
- Immediate rescue and relief camps established at Avanigadda & Nagayalanka
- Distribution of food, clothing, temporary shelters
- Rehabilitation colonies constructed for affected families
- Strengthening of cyclone forecasting and alert systems
🔍 Real-life Example:
After the tsunami, many Diviseema coastal villages received support to restore fishing nets,
boats and agriculture fields affected by saltwater intrusion.
📝 Exam Tip:
When the question mentions “tsunami + Andhra Pradesh,” the correct association is usually
Diviseema region of Krishna district.
🧠 AP Memory Points:
Hudhud → Vizag
Titli → Srikakulam
Kolleru → Wetland protection
Hudhud → Vizag
Titli → Srikakulam
Kolleru → Wetland protection
🔍 Example:
Before a cyclone, AP government evacuates coastal villages and sets up relief camps.
Before a cyclone, AP government evacuates coastal villages and sets up relief camps.
📝 Tip:
When the question is state-specific, always choose coastal examples first.
When the question is state-specific, always choose coastal examples first.
10. Exam Tips & Memory Sheet
Quick Table
| Topic | Key Idea |
|---|---|
| Atmosphere | Layers + Instruments |
| Interior | 4 Layers + Seismic waves |
| Pollution | Types + Sources + Controls |
| Disasters | MPRR steps |
Memory Formulas
- Atmosphere layers: T–S–M–T–E
- Spheres: LABH
- Pollution control: 3R + T
Sample Questions
- Which layer contains the ozone? — Stratosphere
- Which sphere contains rivers? — Hydrosphere
- Which gas is maximum in air? — Nitrogen
📝 Final Tip:
Focus on: definitions, order, classifications, examples.
Focus on: definitions, order, classifications, examples.