Samacheer Kalvi 10th Science Solutions Chapter 22 Pdf
Tamilnadu Board Samacheer Kalvi 10th Science Solutions Chapter 22: Tamilnadu State Board Solution Class 10 Science Chapter 22 – Environmental Management.
Samacheer Kalvi 10th Science Solutions Chapter 22: Overview
Board | Samacheer Kalvi |
Class | 10 |
Subject | Science |
Chapter | 22 |
Chapter Name | Environmental Management |
Samacheer Kalvi 10th Science Solutions Chapter 22 Environmental Management
I.) Fill in the blanks
1.) Deforestation leads to ______________ in rainfall.
Ans:Deforestation leads to reduction in rainfall.
2.) Removal of soil particles from the land is called ______________.
Ans:Removal of soil particles from the land is called soil erosion.
3.) Chipko movement is initiated against ______________.
Ans: Chipko movement is initiated against the cutting down of trees.
4.) ______________ is a biosphere reserve in Tamilnadu.
Ans: Nilgiris is a biosphere reserve in Tamilnadu.
5.) Tidal energy is ___________ type of energy.
Ans: Tidal energy is non-conventional or renewable type of energy.
6.) Coal, petroleum and natural gas are called ______________ fuels.
Ans: Coal, petroleum and natural gas are called fossil fuels.
7.) ______________ is the most commonly used fuel for the production of electricity.
Ans: Coal is the most commonly used fuel for the production of electricity.
II.) State whether True or False. Correct the statements which are false
1) Biogas is a fossil fuel.
Ans: False
Correct statement: Biogas is the mixture of methane, hydrogen sulphide, carbon dioxide and hydrogen.
2) Planting trees increases the groundwater level.
Ans: True
3) Habitat destruction cause loss of wild life.
Ans: True
4) Nuclear energy is a renewable energy.
Ans: False
Correct statement: Nuclear energy is a non-renewable energy source.
5) Overgrazing prevents soil erosion.
Ans: False
Correct statement: In overgrazing, most of the plants are eaten up. If the plants are as remained soil is not exposed. Hence, overgrazing causes soil erosion.
6) Poaching of wild animals is a legal act.
Ans: False
Correct statement: Poaching should be prohibited.
7) National park is a protected park.
Ans: True
8) Wild life protection act was established in 1972.
Ans: True
III. Match the following
Ans:
- Soil erosion: removal of vegetation
- Bio gas: renewable energy
- Natural gas: non-renewable energy
- Greenhouse gas: CO2
- CFL bulbs: energy saving
- Wind: acid rain
- Solid waste: lead and heavy metals
IV.) Choose the correct answer
1.) Which of the following is / are a fossil fuel?
i Tar
ii Coal
iii. Petroleum
a) i only
b) i and ii
c) ii and iii
d) i, ii and iii
Ans:c) ii and iii
Because, coal and petroleum are the fossil fuels.
2.) What are the steps will you adopt for better waste management?
a) Reduce the amount of waste formed
b) Reuse the waste
c) Recycle the waste
d) all of the above
Ans:d) all of the above
Because, above all steps are needed for better waste management.
3.) The gas released from vehicles exhaust are
carbon monoxide ii. Sulphur dioxide iii. Oxides of nitrogen
a) i and ii
b) i and iii
c) ii and iii
d) i, ii and iii
Ans: d) i, ii and iii
Because, vehicle exhaust releases the gases like carbon monoxide, sulphur dioxide and oxides of nitrogen.
4.) Soil erosion can be prevented by
a) Deforestation
b) afforestion
c) Over growing
d) Removal of vegetation
Ans: b) afforestion
Because, if we plant more trees it will prevent soil erosion.
5.) A renewable source of energy is
a) Petroleum
b) Coal
c) Nuclear fuel
d) Trees
Ans:d) Trees
Because, trees are natural renewable source of energy.
6.) Soil erosion is more where there is
a) No rain fall
b) Low rainfall
c) Rain fall is high
d) None of these
Ans: c) Rain fall is high
Because, due to rain fall the soil is exposed and hence more soil erosion occurs.
7.) An inexhaustible resources is
a) Wind power
b) Soil fertility
c) Wild life
d) all of the above
Ans: d) all of the above
Because, all above options are inexhaustible resources.
8.) Common energy source in village is
a) Electricity
b) Coal
c) Biogas
d) Wood and animal dung
Ans: d) Wood and animal dung
Because, in villages wood and animal dung is easily available and free of cost so they are the common energy sources in villages.
9.) Greenhouse effect refers to
a) Cooling of earth
b) Trapping of UV rays
c) Cultivation of plants
d) Warming of earth
Ans: d) Warming of earth
Because, greenhouse effect is due to the warming of earth.
10.) A cheap, conventional, commercial and inexhaustible source of energy is
a) Hydropower
b) Solar energy
c) Wind energy.
d) Thermal energy
Ans:c) Wind energy.
Because, wind energy is the cheap, conventional, commercial and inexhaustible source of energy.
11.) Global warming will cause
a) Raise in level of oceans
b) Melting of glaciers
c) Sinking of islands
d) all of these
Ans:d) all of these
Because, above all options are the causes of global warming.
12.) Which of the following statement is wrong with respect to wind energy
a) Wind energy is a renewable energy
b) The blades of wind mill are operated with the help of electric motor
c) Production of wind energy is pollution free
d) Usage of wind energy can reduce the consumption of fossil fuels
Ans: b) The blades of wind mill are operated with the help of electric motor
V.) Answer in a sentence
1.) What will happen if trees are cut down?
Ans: If trees are cut down it gives ecological problems such as floods, draught, soil erosion, loss of wildlife, extinction of species, imbalance of biogeochemical cycles, alteration of climatic conditions and desertification.
2) What would happen if the habitat of wild animals is disturbed?
Ans: If the habitat of wild animals is disturbed then it causes extinction of animals.
3) What are the agents of soil erosion?
Ans: Agents of soil erosion are high velocity of air wind, air currents, flowing water, and landslide, human activities like deforestation, farming, mining and overgrazing by cattle.
4) Why fossil fuels are to be conserved?
Ans: Fossil fuels forms by natural process such as anaerobic decomposition of buried dead organisms over millions of years. It is slow process and takes lot of time to form fossils, if the fossil fuels are exhausted then no fossil fuels are remained for future generations. So it is necessary to conserve fossil fuels.
5) Solar energy is a renewable energy. How?
Ans: Solar energy is the energy obtained from the sun which is free of cost and vast in amount.
Solar energy is sustainable and also inexhaustible hence it is called as renewable source of energy.
6) How are e-wastes generated?
Ans: The sources of e-wastes are electronic devices such as computers, laptops, mobile phones, printers, monitors, televisions, DVD player, calculators, toys, sports equipment etc.
Household electrical appliances such as refrigerator, washing machine, microwave oven, mixers, grinders, water heater etc.
Accessories like printing cartridges, batteries and chargers.
Short answer questions
1) What is the importance of rainwater harvesting?
Ans: The importance of rainwater harvesting are as follows:
- Due to rainwater harvesting, the rapid depletion of ground water levels will be overcomes.
- Due to rainwater harvesting, we will meet the level of water demand now a days.
- Rainwater harvesting also reduces the floods and soil erosion.
- By rainwater harvesting, we can use that water for various purposes for drinking also. Because water stored in the ground is not contaminated by human and animal wastes.
2) What are the advantages of using biogas?
Ans: The advantages of using biogas are as follows:
- While using biogas there will be no smoke, its use create less pollution.
- In biogas mostly the organic wastes such as bio waste and sewage materials are used. So it is excellent method for using organic wastes.
- The slurry produced in biogas is a good manure rich in nitrogen and phosphorus.
- Biogas is eco-friendly, safe and convenient to use.
- By using biogas we can reduce the greenhouse gases emitted.
3) What are the environmental effect caused by sewage?
Ans:
- It the sewage is disposed without treating it into the rivers then it may harm animals living inside the water.
- Because of the flooding and leaking total sewage get directly mixed into rivers and other water sources which pollutes the water.
- Due the untreated sewage the aquatic ecosystem will be in danger and they can’t survive more.
- Thus, untreated sewage water mostly creates water pollution.
4) What are the consequences of deforestation?
Ans: The consequences of deforestation are as follows:
It gives ecological problems such as floods, draught, soil erosion, loss of wildlife, extinction of species, imbalance of biogeochemical cycles, alteration of climatic conditions and desertification.
VII. Long answer questions
1) How does rainwater harvesting structures recharge ground water?
Ans:
- Rainwater harvesting is the technique for collecting and storing rainwater for future purpose.
- By rainwater harvesting us can store water in underground tanks, ponds, lakes, and check dams for future uses.
- The main aim of rainwater harvesting is to store water under the ground so as to recharge groundwater level.
- There are many methods for harvesting rainwater which are as follows:
1.) Roof top rainwater harvesting:
Most of the rainwater is catched by roof top. The rainwater falling on the roof of the houses, apartments, commercial buildings etc is collected and stored in the tank which is used for domestic purposes.
2.) Recharge pit:
In this method, rainwater from roof and open spaces is collected and stored into percolated pits through which it is filtrated. After filtering this water is stored into recharge pits or ground wells.
3.) Digging of tanks or lakes (Eris):
It is the traditional method mostly used in Tamil Nadu. In this method Eris are developed in each village in a such way that if one of the eri is completely filled with rainwater then the water doesn’t overflow, it get directed to the eri of neighboring village. Because this Eris are interconnected to avoid the rainwater wastage.
4.) Ooranis:
This are the small ponds in which water is collected. And collected water is used for various domestic purposes.
2) How will you prevent soil erosion?
Ans: Soil erosion can be prevented by doing following things:
- We have to retain vegetation cover so that soil cannot be exposed.
- We have to control the cattle grazing.
- Soil organic matter will be improved by crop rotation and soil management.
- We should have to store runoff water in catchment.
- We have to make reforestation, terracing, and contour ploughing.
- We have to control wind speed by panting tress in the form of shelter belt so that soil erosion will be controlled mainly.
3) What are the sources of solid wastes? How are solid wastes managed?
Ans:
- The sources of solid wastes are municipal wastes, hospital wastes, industrial wastes and e-waste etc.
- The solid wastes get dumped in soil and causes landscape pollution. The solid wastes management includes the collection, treatment and proper disposal of solid wastes which are developed due to household and industrial activities.
- There are many methods of solid disposal which are as discussed below:
1.) Segregation:
It is the process in which solid wastes are differentiated as biodegradable wastes and non-biodegradable wastes.
2.) Sanitary landfill:
In this method, solid wastes are dumped into the low lying areas and layers are compacted by trucks to settle them. In 2-12 months wastes materials get stabilised organic matter undergoes decomposition.
3.) Incineration:
In this method, the non-biodegradable solid wastes are burned in the furnace constructed properly at high temperature.
4.) Composting:
In this method, the biodegradable wastes is decomposed by using earthworms or by microbial action and converted into humus.
4) Enumerate the importance of forest.
Ans:
- Forest are important part of our environment and they includes microorganisms, flowering plants, shrubs, climbers, dense trees and it provides vast habitat for wild animals.
- Forest is also economical part of our country as they provides food, wood, fibre, fodder and medicine.
- They are vital for human life and has many renewable natural energy sources. They acts as carbon sink, regulate climatic conditions, increases rainfall, reduce global warming, prevent from natural hazards like flood and landslides, protect wildlife and acts as a catchments for water conservation.
- Ecological balance will be maintained by forest.
5) What are the consequences of soil erosion?
Ans:
The consequences of soil erosion are as follows:
- Soil erosion decreases the agricultural productivity, degrades the ecosystem functions, causes floods and landslides, damage infrastructure and leads to displace people from one place to other.
- Due to the soil erosion the fertile land get lossed.
- It increases pollution and sedimentation in stream and rivers.
- Due to soil erosion the soil lose the ability to hold on water.
- Overall the environmental ecosystem get collapsed due to the consequences of soil erosion.
6) Why is the management of forest and wildlife resource considered as a challenging task?
Ans:
- The uneducated people from rural areas and also educated people see forest as a source of raw materials for industries, and most of the purposes.
- People utilizes them for the developmental uses don’t thinking about the life of organisms in forest.
- They don’t know about chain of ecosystem, once the one of the part get removed all the system collapses. There are many stake holders of forest and it is very hard to make interest of all stake holders in saving forest.
- So it is very challenging to manage forest and wild life resources.
VIII.) Assertion and Reasoning In each of the following question a statement of assertion (A) is given and a corresponding statement of reason (R). Of the four statements given below mark the correct answer.
a.) Both assertion and reason are true and reason is correct explanation of assertion.
b.) Both assertion and reason are true but reason is not the correct explanation of assertion.
c.) Assertion is true but reason is false.
d.) Both assertion and reason are false.
1) Assertion: Rainwater harvesting is to collect and store rain water.
Reason: Rainwater can be directed to recharge the underground water source.
Ans: a. both assertion and reason are true and reason is correct explanation of assertion.
2) Assertion: Energy efficient bulbs like CFL must be used to save electric energy.
Reason: CFL bulbs are costlier than ordinary bulbs, hence using ordinary bulbs can save our money.
Ans: c. Assertion is true but reason is false.
IX.) Higher Order Thinking Skills (HOTS)
1) Although coal and petroleum are produced by degradation of biomass, yet we need to conserve them. Why?
Ans:
- Although coal and petroleum are produced by the degradation of biomass we have to conserve them, because the process of formation of fossil fuels takes many years and it is a long process.
- If we use fossil fuels continuously then this fuel will get exhausted and we can’t store them for future generations.
- So for upcoming generations also we have to conserve these fossil fuels by reducing their consumption.
2) What are the objectives for replacing non-conventional energy resources from conventional energy resources?
Ans:
- Non-conventional energy sources are renewable, they can’t produce any type of pollution and eco-friendly.
- If we use them continuously or rapidly they will not get exhausted because they are prepared in nature in a short period of time, and they are very cheap and easily available.
- So it is most important to use non-conventional energy sources rather than conventional energy sources.
- Wind energy, solar energy are the non-conventional energy sources which can’t exhaust even if we use them continuously.
3) Why is the Government imposing ban on the use of polythene bags and plastics? Suggest alternatives. How is this ban likely to improve the environment?
Ans:
Government is imposing a ban on the use of plastic bags and plastics because of following reasons:
- Plastic is not degradable when it enters in rivers, ponds and lands pollute them on most extent and harms the life of organisms living in water.
- Also if we disposed plastic by burning it, then it also creates an air pollution by emitting poisonous gases in air.
- Due to the accumulation of plastics garbage on lands, it decreases the water absorbing level of land and hence groundwater level get suppressed.
- We have not to use plastic bags and plastics because they are not degradable and highly harmful to living things.
Alternatives:
We have to restrict to use plastic bags and start the use of paper bags or bags made from cloths which can easily degradable and easy to handle. That’s why we have to use our own bags only not provided by shopkeeper.
Improvements in environment due to plastic ban:
- The human health will be safe and thereby nation will be also safe.
- No more dangerous diseases not attacks the organisms.
- Pollution due to plastic is reduced.
X.) Value based questions
1.) Why is it not possible to use solar cells to meet our energy needs? State three reason to support to your answer.
Ans:
- In solar cells solar panels are used to convert the light energy into electrical energy and it is stored in the storage battery. This battery provides direct current which we have to convert it into alternating current by using proper appliances. So it makes solar cell as expensive.
- Hence it is not as much possible to buy solar cells by common people.
- Although the solar energy from sun is free of cost.
- The other disadvantage of solar cell is, it can works only in day time when solar energy from sun is available and during night time it can’t work.
- So it is not easy to use and buy solar cells, hence we can’t meet the energy needs by using solar cells.
2) How would you dispose the following wastes?
Ans:
a.) Domestic wastes like vegetable peels:
Domestic wastes will be disposed by separating the degradable and non-degradable wastes. And used as compost.
Vermiform composting system is used to use domestic wastes like vegetables peels.
b.) Industrial wastes like metallic cans can the disposal protect the environment? How?
And most of the industrial wastes like metal cans will be recycled and reused.
3) List any three activities based on 4R approach to conserve natural resources.
Ans:
The 4R approach is as follows:
1) Reduce:
We have to reduce the use of materials which increases solid wastes and creates pollution such as plastics and plastic bags.
2) Reuse:
We have to repeat the uses of materials such as plastics which are not degradable can be reused, metal wastes also be reused. The domestic wastes can be used as compost.
3) Recovery:
Many materials from garbage can be further used by processing rather than destroying them.
4) Recycle:
When the material cannot be reused and recovered then that material is recycled. That material is used in the form by processing it.