Detailed explanations in West Bengal Board Class 7 Geography Book Solutions Chapter 8 Soil Pollution offer valuable context and analysis.
WBBSE Class 7 Geography Chapter 8 Question Answer – Soil Pollution
Match the following (Page no. 81)
| A | B |
| 1. Smoke from factories | 1. Increase in urbanization |
| 2. Excessive use of pesticides and fertilisers in agricultural fields | 2. Main cause of soil pollution |
| 3. Population growth | 3. Increase fertility of soil |
| 4. Soil pollution | 4. Helps in occurance of acid rain |
| 5. Earthworms, insects and other organisms living in soil | 5. Destroys fertility of soil |
| 6. Disposing offwaste here and there | 6. Various kinds of disease |
Class 7 Geography Chapter 8 Question Answer West Bengal Board – Soil Pollution
Multiple Choice Questions & Answers : (1 mark for each question)
Question 1.
Increase of demand for settlement is the cause of-
i) fertility of soil decreases
ii) deforestation
iii) soil poHution
iv) acid rain
Answer:
ii) deforestation
Question 2.
Soil loses its quality because of-
i) garbage
ii) chemical fertilizers
iii) industrial wastes
iv) all are true
Answer:
iv) all are true
Question 3.
If the soil of the flower pot is polluted-
i) the plamt will die
ii) growth of the plant will stop
hii) flower will not bloom
iv) the plant will change its colour
Answer:
i) the plamt will die
Question 4.
Increase in number of vehicles due to urbanization is the cause of-
i) soil erosion
ii) pollute underground water
iii) acid rain
iv) deforestation
Answer:
iii) acid rain
Question 5.
Accident occured in Union Carbide factory in Bhopal in-
i) 1980
ii) 1990
iii) 1884
iv) 1984
Answer:
iv) 1984
Question 6.
Accident occured in Chernobyl Neuclear reactor in-
i) 2011
ii) 2009
iii) 2010
iv) 2015
Answer:
i) 2011
Question 7.
Use of paper or jute bags instead of polythene can prevent –
i) air pollution
ii) soil pollution
iii) water pollution
iv) sound pollution
Answer:
ii) soil pollution
Question 8.
Use of chemical fertilizers and pestisides excessively can cause –
i) air pollution
ii) sound pollution
iii) water pollution
iv) soil pollution
Answer:
iv) soil pollution
Fill in the blanks : (1 mark for each question)
1. Use of more _______ manure in agriculture can prevent soil pollution.
Answer:
organic
2. Planting more trees prevent _______ pollution.
Answer:
soit
3. Smoke emitted from vehicles cause _______.
Answer:
air pollution
4. Industrial wastes pollute surface and _______ water.
Answer:
underground
5. Trace of pesticides in crops may cause _________
Answer:
cancer
6. Demand of industrial products ________ on account of population growth.
Answer:
increase
7. Virus and _______ grow in garbage heap of houses, markets and hospitals.
Answer:
bacteria
8. Less amount of crops grow in the rough soil of ______.
Answer:
Purulia
9. Accident occured at _____ of Chernobil in Ukraine.
Answer:
nuclear reactor
10. The is the living place of all plants and _______.
Answer:
animals
State whether True or False : (1 mark for each question)
1. Soil is the best gift of nature.
Answer:
true
2. 80% people of the total population of this earth is living on 12 % of total land mass of the earth.
Answer:
false
3. Soil is polluted when it loses its fertility or quality.
Answer:
true
4. Indiscriminate use of soil causes soil erosion.
Answer:
true
5. Poisonus gases emitted from factories causing water pollution.
Answer:
false
6. Excavation of excessive soil for making bricks in kilns is one of the causes of soil erosion.
Answer:
true
7. DDT is one kind of chemical fertilizer.
Answer:
false
8. Soil is present at the uppermost layer of landmass.
Answer:
true
Match the column A with column B.
| A | B |
| 1) Deforestation is connected with | a) cause acid rain |
| 2) Increase in need of food | b) thermal power plants |
| 3) Insects and worms die | c) in Bhopał, India |
| 4) Smokes emitted from vehicles | d) urbanization |
| 5) In garbage heap | e) due to population growth |
| 6) Fly ashes spread from | f) causes soil erosion |
| 7) Union Carbide factory is situated | g) virus and bacteria grow |
| 8) Indiscriminate use of soil | h) for soil pollution |
Answer:
1. Deforestation is connected with urbanization.
2. Increase in need of food due to population growth.
3. Insects and worms die for soil pollution.
4. Smokes emitted from vehicles cause acid rain.
5. In garbage heap virus and bacteria grow.
6. Fly ashes spread from thermal power plants.
7. Union Carbide factory is situated in Bhopal, India.
8. Indiscriminate use of soil causes soil erosion.
Very Short Questions & Answers : (1 mark for each question)
Question 1.
From what soil is originated?
Answer:
Soil is originated due to erosion of rocks over a long period.
Question 2.
What is soil?
Answer:
Soil is upper level of landmass.
Question 3.
When soil is polluted?
Answer:
Soil is polluted when it loses its fertility or quality.
Question 4.
What is the living place of plants and animals?
Answer:
Soil is the living place of plants and animals.
Question 5.
Why huge amount of paddy, jute and vegetables grow on the banks of the Ganga?
Answer:
The silt soil of this area is very fertile.
Question 6.
Which is not bio-degradable?
Answer:
Polythene and plastic goods are not bio-degradable.
Question 7.
How transport is responsible for air pollution?
Answer:
Smokes emited from vehicles cause air pollution.
Question 8.
What is the relation between population growth and industrialisation?
Answer:
Demand for industrial productsincrease on account of population growth.
Question 9.
When Bhoopal Gas accident occured?
Answer:
Bhoopal Gas accident occured in 1984.
Question 10.
What is the advantage of using paper or jute bags instead of polythene?
Answer:
Soil pollution can be prevented.
Question 11.
What is responsible for acid rain?
Answer:
Air pollution by poisonus gas emitted from factories is responsible for air pollution.
Question 12.
What is the cause of increase of demand for settlement?
Answer:
Population growth is the cause of increase of demand for settlement.
Short Questions & Answers : (2 marks for each question)
Question 1.
What is the result for excessive use of chemical fertilizers and pesticides?
Answer:
Food value of crops is deminished, trace of pesticides in crops may cause cancer. Small animals, insects and worms living in soil die.
Question 2.
State the incident of Bhopal.
Answer:
In 1984 from the factory of Bhopal in India poisonous gas mixed with the air resulted too many people’s death and many were disabled for this reason.
Question 3.
How is soil polluted from the Thermal Power plants ?
Answer:
The flying ash and the part of burnt charcoal mix with soil. thus the soil is polluted.
Question 4.
What may happen if filthy oil is poured in to the flower pot?
Answer:
If dirty oil is poured at the root of the plant the plant could not be nounished from the soil. The plant will die as the soil becomes poisonous.
Question 5.
Soil hold the life — Explain.
Answer:
The best gift of nature is soil. The upper layer is of the land mass is soil. Human beings and other living things depend on soil for their habitat, food and shelter. So it can be clearly stated that soil holds life on Earth.
Question 6.
What happened in Chernobyl and Fukusima Daichi?
Answer:
Accident occured in 1986 in Chernobyl nuclear reactor in Ukraine. An other accident occured in Fukushima Daichi nuclear reactor in Japan in 2011.
Long Questions & Answers : (3 marks for each question)
Question 1.
What are the causes of soil pollution ?
Answer:
i) Pollution from industry : The poisonous waste, sewage, oily substances, metalic substances, plastic from industries are thrown out in the soil and make the soil polluted. Gasious substances mix with soil with rain water. Flyash from thermal power plant mixes up with soil and destroys soil fertility.
ii) Use of fertilizer and insecticide : Excessesive quantity of fertilizer and insecticide is used to increase the crop production. But this fertilizer closes the gaps of the soil and thus the air can not enter in soil. For this reason soil fertility reduces. The insecticides can destroy the ecofreindly insects with other insects.
iii) Plastic like garbage : The plastic is artificial organic compound which is a non-decaying substance. It can not be destroyed easily. At present plastic is used in many countries. These can block the drains and canals and destroy the fertility of soil.
iv) Over growth of population : For over growth of population the household garbage used by the people is thrown on the soil and makes it polluted.
v) Felling of trees : The forest cover of the earth is gradually decreasing due to the felling of trees unwisely. So the soil is eroded. The rainfall is decreasing. The soil pollution is occured for the lowering of soil fertility.
Question 2.
What are the harmful effects of soil pollution?
Answer:
- The farming is effected by soil pollution.
- Lead, murcury, zinc are mixed with soil and change the acidic and alkaline quality of the soil.
- The useful bacteria of earth is destroyed for soil pollution.
- Excessive use of fertilizer and insecticide changes the taste of the crops and nutrient value. Thus various diseases of malnutrition is caused. The nerves of human body, eye sight become week.
- The pollutants from nuclear reactor mixes with soil. This chemicals accumulate the plants that grew in this soil. The cells of human body are destroyed and it causes cancer and other disease.
- Soil pollution causes tremendous effect on living world. So the soil pollution is responsible for destroying balance of nature.
Question 3.
What are the preventive measure of soil pollution?
Answer:
- The waste of household should be thrown away in a certain place.
- Instead of polly bag, paper bag, sal leaves, jute bag, earthen pot should be used.
- The use of fertilizer in the farmland should be reduced. Use of pesticide should be replaced by use of organic method.
- The garbage should be treated by highly developed technology.
- Respond to nature’s call we should proper toilet.
- We should be aware at the time of using radioactive substance.
- Inflamable garbage should be burnt.
- The ash of thermal power station should be reused in proper way to prevent soil pollution.