
π Chapter 14 β Natural Resources
π§ Easy & Detailed Notes
πΉ 1. What Are Natural Resources?
- All materials available in nature used by humans are natural resources.
Examples: Air, Water, Soil, Forests, Wildlife, Minerals, etc.
πΉ 2. Types of Natural Resources
Type | Example |
---|---|
Biotic (living) | Plants, animals |
Abiotic (non-living) | Water, air, minerals |
| Renewable | Sunlight, air, water |
| Non-renewable | Coal, petroleum |
πΉ 3. Atmosphere
- Thin layer of air around Earth.
- Maintains temperature and protects from UV rays.
πΉ 4. Air Pollution
- Contamination of air by harmful gases (COβ, CO, SOβ, NOβ), dust, etc.
Effects: - Breathing problems
- Global warming
- Acid rain
- Ozone depletion
πΉ 5. Water Pollution
- Mixing of harmful substances (chemicals, sewage) into water.
Effects: - Diseases
- Death of aquatic life
- Eutrophication
πΉ 6. Water Cycle
- Continuous process of evaporation β condensation β precipitation β collection.
πΉ 7. Soil
- Uppermost layer of Earth, supports plant growth.
Soil formation: Weathering of rocks + biological activity.
πΉ 8. Soil Pollution
- Mixing of harmful chemicals into soil.
Causes: Pesticides, waste dumping, plastic
πΉ 9. Fossil Fuels
- Non-renewable sources like coal, petroleum, natural gas.
Formed from dead plants/animals over millions of years.
πΉ 10. Greenhouse Effect
- Heat trapped by gases (COβ, methane) β Earth’s temp rises.
πΉ 11. Ozone Layer
- Absorbs harmful UV rays.
Damaged by CFCs.
πΉ 12. Rainwater Harvesting
- Collecting and storing rainwater for future use.
Example: Rooftop tanks, pits
πΉ 13. Ganga Action Plan
- Launched in 1985 to reduce water pollution in River Ganga.
β MCQs
- Which one is a renewable resource?
a) Coal
b) Petroleum
c) Water
d) Natural gas - Major cause of ozone depletion:
a) COβ
b) CFCs
c) NOβ
d) Oβ - Greenhouse effect is caused by:
a) Oβ
b) CO
c) COβ
d) SOβ - Fossil fuels are:
a) Renewable
b) Unlimited
c) Non-renewable
d) Clean energy - Ganga Action Plan was started in:
a) 1980
b) 1985
c) 1990
d) 2000 - Acid rain is caused by:
a) Oxygen
b) Hydrogen
c) SOβ and NOβ
d) Carbon - Which of these pollutes soil?
a) Paper
b) Pesticides
c) Water
d) COβ - Which gas traps most heat?
a) COβ
b) Nitrogen
c) Oxygen
d) Helium - Ozone layer is present in:
a) Troposphere
b) Stratosphere
c) Mesosphere
d) Thermosphere - Which one is abiotic resource?
a) Cow
b) Tree
c) Water
d) Bird - Main component of air:
a) Oxygen
b) Carbon dioxide
c) Nitrogen
d) Argon - Soil forms from:
a) Wind
b) Water
c) Weathering of rocks
d) Sunlight - Which is not water pollution cause?
a) Pesticides
b) Sewage
c) Sunlight
d) Factory waste - Air pollution affects:
a) Heart
b) Lungs
c) Bones
d) Skin - Best way to conserve water:
a) Deforestation
b) Pollution
c) Rainwater harvesting
d) Burning fuels
β Assertion & Reason
A: Coal is renewable.
R: It can be formed in a few years.
a) Both true, R explains A
b) Both true, R doesnβt explain A
c) A true, R false
d) A false, R true
A: CFCs damage ozone.
R: CFCs break ozone molecules.
a) Both true, R explains A
b) Both true, R doesnβt explain A
c) A true, R false
d) A false, R true
A: Soil supports plant life.
R: It contains nutrients.
a) Both true, R explains A
b) Both true, R doesnβt explain A
c) A true, R false
d) A false, R true
A: Ganga Action Plan reduced water pollution fully.
R: Waste dumping was stopped totally.
a) Both true
b) Both false
c) A false, R false
d) A true, R false
A: Rainwater harvesting conserves water.
R: It stores rainwater for use.
a) Both true, R explains A
b) Both true, R doesnβt explain A
c) A true, R false
d) A false, R true
β Case-Based Study
π Passage:
A village uses rainwater harvesting to conserve water. Pits are dug to collect rainwater. The water is used in dry seasons. People also plant trees and avoid plastic.
- What method is used to save water?
a) Dam building
b) Rainwater harvesting
c) Borewell
d) Well - Why is rainwater harvesting important?
a) Wastes water
b) Prevents rainfall
c) Conserves water
d) Pollutes soil - Planting trees helps in:
a) Increasing pollution
b) Soil erosion
c) Climate balance
d) Causing floods - Plastic harms soil because:
a) It is biodegradable
b) Gets absorbed in soil
c) Is non-biodegradable
d) Grows plants - Why store water in dry season?
a) For rain
b) For decoration
c) To use when scarce
d) For cooling
β Reason-Based Questions
- Why is air pollution harmful?
It causes breathing problems and harms environment. - Why should we reduce use of fossil fuels?
They are non-renewable and cause pollution. - Why do we need to protect ozone layer?
It protects us from UV rays. - Why is rainwater harvesting needed?
To store water and reduce dependency on groundwater. - Why is planting trees important?
They prevent soil erosion and purify air. - Why do CFCs damage ozone?
They break ozone molecules in stratosphere. - Why is water cycle important?
It maintains water availability on Earth. - Why do factories pollute air and water?
Due to release of harmful gases and chemicals. - Why is Ganga polluted?
Due to sewage, industrial waste, and garbage. - Why is soil erosion dangerous?
It reduces soil fertility and plant growth. - Why should plastic be avoided?
It pollutes land and water and is non-degradable. - Why do we need clean air?
To stay healthy and prevent diseases. - Why is atmosphere important?
It protects Earth and supports life. - Why should we avoid deforestation?
It causes imbalance in ecosystem. - Why should we treat sewage before disposal?
To reduce water pollution and protect life.
β Final Answer Key
MCQs:
1βc, 2βb, 3βc, 4βc, 5βb, 6βc, 7βb, 8βa, 9βb, 10βc, 11βc, 12βc, 13βc, 14βb, 15βc
Assertion & Reason:
16βd, 17βa, 18βa, 19βb, 20βa
Case-Based:
21βb, 22βc, 23βc, 24βc, 25βc