Grade -5 science topic is How human activities effect environment

1. How Human Activities Affect
environment
MADE BY :- KOBID MANI RIJAL
STUDENT OF GRATE- 5
SCHOOL’S NAME- HAMRO ENGLISH BOARDING SCHOOL
ITAHARI-4,SUNSARI

2. Glossary: A dictionary of scientific/technical term
Environment : the natural world around us which consists of living beings and non-
living things
Pollute : to add harmful or dirty substance to the environment
Pollution : the process of making the environment dirty
Suffocation : difficulty in breathing due to lack of fresh air
Irrigation : supply of water to area of land so that crop will grow
Habitat : the place where plant and animal live
Garbage : waste food, paper, etc. that you throw away
Sewage : used water and waste substance that are produce by human

3. How Human Activities
Affect Environment
A variety of plant and animal are found in the environment. Among all the plant and animals, Only human
Beings modify natural environment to fulfil their needs. Human beings play an important role to conserve or
Destroy natural environment. Various human activities affect air, water, soil, plants, and animals. Natural
Natural environment is being more polluted day by day due to garbage on the road. Some human being
Defecate on open field. They dispose untreated sewage into rivers. The human activities causes
Environment pollution . The mixing of harmful and unwanted substance in the environment is called
Environment pollution.
In this unit, we will study the adverse effects on air, water, soil and forest due to human activities.
How Human Activities Affect Environment Do you know
-Air is the mixture of various gases
Like nitrogen, oxygen, water
vapor, etc.
-Living beings take oxygen and
release carbon dioxide while
breathing.

4. Air
Air is very important matter for living brings. They cannot survive with out air. Both plant and
animal take oxygen and release carbon dioxide while breathing. Similarly, green plants use
carbon dioxide and release oxygen during photosynthesis.
We all need fresh and clean air to breathe. But the air that we breathe is being polluted day by
day due to human activities. Mostly in urban areas, air contains various unwanted substance
like dust, harmful chemicals, industries gases, bad smell, smoke, etc. Such type of air is called
polluted air. The contamination of air with harmful and unwanted substance is called air
pollution.

5. Causes of air pollution
1) Smoke released by burning of different substance like plastic, fire wood, coal, petrol, diesel, etc.
2) Smoke released by brick kilns, industries, etc.
3) Exhaust gases emitted by vehicles like truck, bus , car, van, etc.
4) Smoke produce due to wild fire or forest fire.
5) Dust particles released during the movement of vehicles on the road, construction of roads and
building, etc.
6) Mixing of bad smell into air due to decaying of dead of animal, garbage, etc.
Effect of air pollution
1) Breathing in polluted air causes various diseases
like pneumonia, asthma, tuberculosis, lung
cancer, etc.
2) It causes skin diseases.
3) It causes cough and suffocation.
4) Polluted air increases the temperature of the
environment.

6. Water
Water is one of the most important substance essential for survival of living beings. Plants and animal cannot
Survive without water. About two- thirds of the surface covered with water. It exist
In three state, viz. solid, liquid and gas. In solid state, it found in river, lake, pool, sea,
Etc. In gaseous state, water is found in the form of vapor. Human beings use water
For various purpose like drinking, washing, bathing, irrigating, cooking, generation
Hydroelectricity and so on. Water is also used in various sources industries and in
Construction work. We get water from various sources like river, lake, pool, stream,
Fountain, well, etc. We all need clean pure water to use. But the sources of water
to use. But the sources of water are being polluted day by day due to human
Activities. The contamination of water due to mixing of harmful and unwanted
substance is called water pollution.
Fountain

7. Causes of water pollution
1) Disposal of unwanted sewage in the sources of water
2) Defecating and urinating in the sources of water or near the sources of water
3) Discharging untreated waste from industries, hospital, , etc. into river
4) Bathing of humans and cattle's in the sources of water
5) Throwing waste materials and dead animal into water
6) Washing clothes and vehicles in the sources of water
7) Excessive use of detergent, insecticides, pesticides, chemical fertilizers, etc.
Effect of air pollution
1) Drinking of polluted/ contaminated water may causes various water borne diseases like
Diarrhea, typhoid, cholera, dysentery, etc.
2) Polluted water may cause death of aquatic animals.
3) Polluted water used for irrigation causes abnormal growth of plants.

8. Soil
Soil is the soft substance that forms the surface of the land. Soil is made
of fine sand particles, clay, humus, etc. About one- third of the earth is
occupied by soil. Soil gives shelter to different plant and animals. We
grow fruits, crops, vegetable, etc. on the soil. We construct houses,
buildings, road, etc. on the soil or land. All land plat and animal
depend on the soil to get food and shelter. So, soil is one of the most
important substance for living beings. But soil is being polluted day by
day due to human activities. The mixing of harmful and unwanted
substance in the soil is called soil polluction.

9. Causes of water pollution
1) Throwing of house hold waste on the soil or land
2) Improper disposal of garbage and sewage on soil
3) Improper disposal of industrial wastes on soil
4) Excessive use of chemical fertilizer, insecticides, pesticides, etc. on soil
Effect of soil pollution
1) Polluted soil may spread various diseases in plant and animals.
2) It causes contamination of crops and vegetables.
3) It affect the habitat of animal s.
4) Plastic glasses, etc. in the soil affect its fertility.

10. Forest
A forest is a very important natural resources for humans and other animal. A forest consist of a large
Number od trees, shrubs, grass, wild animal, etc. All wild animal and birds get food and shelter from a
Forest. Human being get timber, fire hood, grass, fodder, fruits, medicines, etc. from the forest. Forest
also help in rainfall and maintaining balance in the amount of oxygen and carbon dioxide in the
environment. Forest help to reduce soil erosion to control flood and land slide. A variety of plant and
animal get habitat from forests.
Green forest is the property of our country. A variety of wild animal like elephant, rhinoceros, tiger, bear
Dear, black buck, etc. and different type of types of bird are found in the forests of Nepal. Many tourist
Visit Nepal to observe wildlife. Now- a- days, a large number of trees
Are being cut day by day to get a land for settlement and
Construction work. The cutting down of large number of trees to get
Clear land is called deforestation. Deforestation is a burning issue in
the context of Nepal.

11. Causes of deforestation pollution
1) Uncontrolled cutting down of trees to get land for
cultivation, settlement, road construction, etc.
2) Cutting down of trees for timber and firewood
3) Overgrazing
4) Wild fire or forest fire
forest fireOvergrazing

12. Effect of deforestation pollution
1) Deforestation affect the rain cycle.
2) It leads to extinction of wild animal and plant.
3) It causes soil erosion, land slide and flood.
4) It affect the balance of oxygen and carbon dioxide in the environment.

13. Flood, land slide and soil erosion
During the rainy season, the level of water in rivers, stream, etc. increases due to heavy
Rainfall and water overflows the blanks. This overflow of water is called flood. Flood mainly occurs in the
Terai regions and unplanned city areas during the rainy season. Land slide is the sliding downward of a
Large mass of land in hilly regions or in slopes. Every year flood and land slide damage a lot of lives and
Property in Nepal during the rainy season.
Flood land slide
Soil erosion is the process in which running water and blowing wind carry away the top soil from one place
To another.
Soil erosion is caused by heavy rainfall, wind, deforestation, uncontrolled grazing, unscientific agricultural
Technique on slopes, etc. Various human activities are responsible for flood, land slide and soil erosion.