Environmental Science PYQ April 2024 67/TUS/2

Environmental Science NIOS Question Paper April 2024

CORE MODULES

OBJECTIVE QUESTIONS TYPE – I

1. (i) According to an archeological study, foragers lived in/under

(A) huge canopies of trees

(B) temporary oval hut-like shelters

(D) permanent built-in houses 1

Ans: (B) temporary oval hut-like shelters

(ii) Draught animals are

(A) animals living in wild

(B) animals used to carry goods

(D) animals that provide safety and security

Ans: (B) animals used to carry goods

2. The correct order of evolutionary stages of human species is

(A) Homo habilis, Homo sapiens, Homo erectus

(B) Homo sapiens, Homo erectus, Homo habilis

(D) Homo erectus, Homo Habilis, Homo sapiens 1

Ans: (C) Homo habilis, Homo erectus, Homo sapiens

3. (i) The factors leading to rise in population are

I. increase in food production

II. treatment of diseases

III. pollution of natural bodies

IV. depleting natural resources

Select the correct answer :

(A) I and II

(B) II and III

(D) II and IV 1

Ans: (A) I and II

(ii) The impact of population growth on environment is

(A) conservation of water resources

(B) decreased fossil fuel consumption

(D) decreased soil pollution

Ans: (C) pollution of rivers and other water bodies

4. Speciation is a process by which

(A) adaptation of species occurs

(B) new species are formed

(D) dying out of species occurs 1

Ans: (B) new species are formed

5. (i) Steppes is a

(A) tropical forest

(B) desert

(D) temperate forest 1

Ans: (C) grassland

(ii) Animal found in tundra region is

(A) rabbit

(B) reindeer

(D) bear

Ans: (B) reindeer

6. (i) An example of littoral forest ecosystem is

(A) mangroves

(B) islands

(D) deltas 1

Ans: (A) mangroves

(ii) Which one of the following is not an example of ecotone?

(A) Grassland

(B) Estuary

(D) Pond

Ans: (D) Pond

7. Primitive humans decided to lead a settled life as they

(A) felt the need for shelter and security

(B) were increased in numbers

(D) were tired of moving around 1

Ans: (A) felt the need for shelter and security

8. (i) Slums are

(A) planned part of villages

(B) planned area of cities

(D) clusters of huts or homes in villages 1

Ans: (C) clusters of huts or homes in parts of cities

(ii) Difficulty faced by migrants in urban life is

(A) inadequate hygiene and sanitation conditions

(B) poor means of transport and communication

(D) lack of job opportunities

Ans: (A) inadequate hygiene and sanitation conditions

9. Providing habitat for various organisms is

(A) productive function of forests

(B) protective function of forests

(D) both productive and regulative functions of forests 1

Ans: (B) protective function of forests

10. Hereditary diseases are due to

(A) only genetic influences on health

(B) only behavioural influences on health

(D) both behavioural as well as environmental influences on health 1

Ans: (A) only genetic influences on health

11. Global warming is due to

(A) depletion of ozone layer

(B) loss of biodiversity

(D) dumping of hazardous waste 1

Ans: (C) greenhouse effect

12. Which of the following is not a non-conventional source of energy? 1

(A) Geothermal power

(B) Compressed natural gas

(D) Hydel power

Ans: (B) Compressed natural gas

13. (i) The cropping practice in which different plants maturing at different times are planted together, is known as

(A) polyculture

(B) crop rotation

(D) polyvarietal cultivation 1

Ans: (A) polyculture

(ii) Sustainable agriculture is one that

(A) supports loss of production

(B) uses natural resources in an inefficient manner

(D) will last for generations to come

Ans: (D) will last for generations to come

OPTIONAL MODULE—8A ( Water Resource Management )

14. (i) In large cities and towns, groundwater is not fit for drinking, because

(A) It contains microbes

(B) It contains high concentration of dissolved minerals

(D) It is coloured 1

Ans: (B) It contains high concentration of dissolved minerals

(ii) The easiest method to remove large suspended impurities from water is

(A) sedimentation

(B) coagulation

(D) chlorination

Ans: (A) sedimentation

15. (i) Some parts of India suffer from severe water scarcity due to

(A) lack of sufficient rainfall in the country

(B) uneven distribution of rainfall in the country

(D) droughts in the country 1

Ans: (B) uneven distribution of rainfall in the country

(ii) Tanks, ponds, check dams are structures used to

(A) store rainwater

(B) recharge groundwater

(D) disinfect surface water

Ans: (A) store rainwater

16. (i) The attributes of groundwater are

I. It is sustainable

II. It is easily contaminated

III. It is less polluted

IV. It has a low vulnerability to drought

Select the correct answer :

(A) I, II and III

(B) I, III and IV

(D) I, II and IV 1

Ans: (B) I, III and IV

(ii) Some techniques of groundwater management and conservation are

I. artificial recharge

II. percolation tank construction

III. Catchment Area Protection

IV. check bund construction

Select the correct answer :

(A) I and II

(B) II and III

(D) I and IV

Ans: (A) I and II

OPTIONAL MODULE—8B ( Energy and Environment )

14. (i) Direct use of solar energy is in

(A) wind mills

(B) photosynthesis in plants

(D) tidal power plants 1

Ans: (C) photovoltaic cells

(ii) Alternative source of energy is

(A) non-renewable source of energy

(B) inexhaustible source of energy

(D) non-conventional source of energy

Ans: (D) non-conventional source of energy

15. (i) An example of gaseous biofuel is

(A) methane

(B) gasohol

(D) sulphur dioxide 1

Ans: (A) methane

(ii) Biomass is used as/in

(A) a source of construction material

(B) a source of heat and power generation

(D) treatment of water

Ans: (B) a source of heat and power generation

16. (i) CFL should be used in place of ordinary bulbs as they

(A) use less electricity

(B) are cheaper than ordinary bulbs

(D) are available in a standard shape 1

Ans: (A) use less electricity

(ii) An energy conservation plant should be developed for every household as

(A) It is an environment friendly and economically sound action

(B) It will make use of appliances easy and convenient

(D) It will deplete the energy resource

Ans: (A) It is an environment friendly and economically sound action

CORE MODULES

OBJECTIVE QUESTIONS TYPE–II

17. (a) Expand EIA.

(b) Name two important aspects of EIA. 1+1=2

Ans:

a) Environmental Impact Assessment
b) The important aspects of EIA are:
- Risk assessment,
- Environmental management and
- Post product monitoring.

(a) What is meant by environmental clearance?

(b) Name any two projects requiring environmental clearance.

Ans:

a) Environmental clearance or the ‘go-ahead’ signal is granted by the Impact Assessment Agency in the Ministry of Environment and Forests, Government of India.
b) Industries, Mining, Thermal power plants, and River valley projects

18. Answer any six questions of the following: 1×6=6

(a) “Evaluation of EIA is possible only if EIA report is reliable.” What does this statement mean?

(b) What are village forests?

(c) What is the aim of IPM?

(d) Mention two important agriculture inputs that are avoided in organic farming.

(e) How do exotic species often wipe out the native species?

(f) How does acid rain affect leaves of plants?

(g) Why should water be conserved for life?

(h) Fossil fuels are called non-renewable fuels. Why?

Ans:

a) An effective EIA exercise is focused, time-bound, cost-effective, and makes assessment understandable.
b) Reserved forests assigned to a village community are called village forests.
c) The aim of IPM is not to eradicate the pest population but to keep the crop damage to an economically tolerable level.
d) Applying chemical fertilizer and prolonged use of chemical fertilizers.
e) Nile perch, an exotic predatory fish introduced into Lake Victoria (South Africa) threatened the entire ecosystem of the lake by eliminating several native species of the small Cichlid fish that were endemic to this freshwater aquatic system.
f) Acid rain damages the cuticle of plant leaves, resulting in etiolation of foliage.
g) No organism can survive without water.
h) It is obtained from deep inside the earth and thus is a non-renewable energy resource.

19. Answer any six questions of the following: 1×6=6

(a) Name a country that had a Forest Policy since 1984.

(b) Expand the abbreviation of IPR.

(c) Which is the most dangerous consequence of population explosion?

(d) Name a chemical compound which is obtained by anaerobic digestion of manure.

(e) Name the most abundant group of animals recorded in India.

(f) What is the thinning of stratospheric ozone layer over the Antarctic region known as?

(g) Name the major pollutant released from oil refineries.

(h) What is the name given to tropical deciduous forests found in the State of Kerala in India?

Ans:

(a) India
(b) Intellectual Property Rights
(c) Poverty
(d) Methane
(e) Arthropods
(f) Ozone hole
(g) Sulphur dioxide
(h) Monsoon forests

20. Fill in the blanks by using the appropriate words given below (any four): 1×4=4

(planktons, ex-situ, carcinogenic, carrying capacity, biofuel, work)

(a) Maximum pressure that the environment can withstand on account of human activities is known as _____.

(b) Energy may be defined as capacity to do _____.

(c) Organic waste can be converted by bacteria into _____.

(d) Conservation of plants and animals outside their natural habitat is known as _____ conservation.

(e) The cancer-causing agents are known as _____.

(f) Microscopic floating organisms such as algae and protozoans are called _____.

Ans:

(a) carrying capacity
(b) work
(c) biogas
(d) ex-situ conservation
(e) carcinogens
(f) planktons

21. Write True or False (any three): 1×3=3

(a) A protocol is an international agreement that stands on its own but is linked to an existing convention.

(b) Sustainable development is the development that meets the needs of the present compromising the ability of the future generations to meet their own needs.

(c) Overexploitation is one major cause of environmental degradation.

(d) Nag champa tree can be used to produce biodiesel.

(e) Kinetic energy of wind is converted into electrical energy and used.

Ans:

(a) True
(b) False
(c) True
(d) True
(e) True

OPTIONAL MODULE—8A ( Water Resource Management )

22. Water covers about three-quarters of the Earth’s surface, but how much of it is freshwater? 1

Ans: 2.7%

Name two sources of freshwater.

Ans: Fresh water is found in lakes, rivers, streams, ponds, and in the ground.

23. Mention two main techniques of rainwater harvesting. 1

Ans:

Pits: Recharge pits are constructed for recharging the shallow aquifer.
Dug wells: Existing dug wells may be utilized as a recharge structure, and water should pass through filter media before being put into the dug well.

Mention how in ancient times houses in Western Rajasthan conserved water.

Ans: In ancient times, houses in parts of western Rajasthan were built so that each had a rooftop water harvesting system. Rainwater from these rooftops was directed into underground tanks.

24. What is gray water? 1

Ans: Grey water is defined as untreated household wastewater, which has not come into contact with toilet waste.

Mention two ways by which wastewater can be reused.

Ans: The wastewater from industrial or domestic sources can be used after proper treatment for irrigation, recharging groundwater, and even for industrial or municipal use. If agricultural lands are available close to cities, municipal wastewater can be easily used for irrigation.

OPTIONAL MODULE—8B ( Energy and Environment )

22. When growth of economy can withstand global competitiveness in terms of energy? 1

Ans: Growth of the economy will stand global competitiveness only when it depends on cost-effective or cheaper and environmentally friendly energy sources.

Give one important impact of energy use on environment.

Ans: Apart from depletion of energy resources, the use of energy, especially the burning of fossil fuels, causes environmental pollution. Burning of fossil fuels emit green house gases that cause global warming.

23. What is bagasse? 1

Ans: Bagasse is the leftover of cane after it is crushed and its juice extracted. It is used as a biofuel to generate electricity.

Define methanogenesis.

Ans: Methanogenesis is a microbial process involving many complex and differently interacting species, but most notably, the methane-producing bacteria.

24. What is the cause of air becoming wind? 1

Ans: Heat from the sun causes temperature differences between areas, causing the wind to blow.

Why is wind energy called indirect solar energy?

Ans: About 2% of the sunlight striking the earth is converted into the kinetic energy of moving

air called wind. This is why wind energy is an indirect form of solar energy.

CORE MODULES

SUBJECTIVE PART

25. What all is assessed in EIA? 2

Ans:

(i) Assessment of existing environmental status.
(ii) Assessment of various factors of the ecosystem (air, water, land, biological).
(iii) Analysis of adverse environmental impacts of the proposed project to be started.
(iv) Impact on people in the neighbourhood.

26. How are forests getting denuded? 2

Ans: When the rate at which trees are cut far exceeds the rate at which trees grow, forests get denuded.

Why is extinction of wildlife species on the rise?

Ans: Extinction of wildlife species is on the rise because their natural habitats are being destroyed due to deforestation.

27. Differentiate between rural and urban settlements on the basis of the following factors: 2

(a) Occupation

(b) Population density

Ans:

	Rural Society	Urban Society
Occupation	Agriculture- cultivators and their families are in the majority. Few are in non-agricultural pursuits.	Mostly industrial workers, traders, professionals, and those working in offices. Mostly engaged administration. All non-agricultural occupations.
Population density	Comparatively lower density of population	Large population density.

28. This is an extensive, sandy region in North-West India and Eastern Pakistan. Identify this region and name one plant species, one animal species and one bird species found in this region. 2

Ans: Thar Desert.

Plant species: Khejri
Animal species: Indian gazelle
Bird species: The great Indian bustard

29. Give two reasons to show the importance of conservation of biodiversity. 2

Ans: Conservation of biodiversity is important to:-

Prevent the loss of genetic diversity of a species,
Save a species from becoming extinct, and
Protect ecosystems from damage and degradation.

30. What are two strategies for effective management and conservation of water? 2

Ans: Effective management and conservation of water has to incorporate the following two strategies:

(1) Reduction in loss and wastage of water.
(2) Harvesting, collection and improved storage of water.

31. Explain the following terms: 2

(a) Mutualism

(b) Commensalism

Ans:

Mutualism is a close association between two species in which both species benefit.
Commensalism is a relationship where one of the species benefits while the other is neither harmed nor benefited.

What is ecological succession? Name different types of ecological successions.

Ans: The process by which communities of plant and animal species in an area are replaced or changed into another over a period of time is known as ecological succession.

There are two types of successions (i) Primary succession and (ii) Secondary succession.

32. Explain the role of the following in agriculture as biofertilizers: 2

(a) Rhizobium

(b) Azospirillum

Ans:

(a) Rhizobium: Rhizobium is a symbiotic bacteria forming root nodules in legume plants. The nodule bacteria fix more nitrogen (N₂) than is needed by the legume plant and the bacteria.
(b) Azospirillum: These are aerobic, free-living nitrogen fixers which live in associative symbiosis. In this type of association, bacteria live on the root surface of the host plant and do not form any nodules with the roots of grasses. It increases crop yield, and its inoculation benefits the crop. They also benefit the host plants by supplying growth hormones and vitamins.

In the context of soil management, give two objectives of varietal improvement of crops.

Ans: Some of the objectives of varietal improvement are:

(i) development of high-yielding varieties of crop plants.
(ii) food crops developed for better and higher nutritional quality, like protein quality in pulses, baking quality in wheat, preserving quality in fruits and vegetables, and oil quality in oilseed-producing plants.
(iii) development of crop varieties resistant to diseases and pests.
(iv) improving varieties for resistance against heat, cold, frost, draught and waterlogging.

33. Define population. Why is it important to study population? Explain anyone point. List four major periods of human population growth. 4

Ans: ‘Population’ is defined as a group of freely interbreeding individuals of the same species present in a specific area at a given time.

Its study helps us to:

Provide data on the total manpower available now and in future;
Estimate the total amounts of goods/ services required currently and in future;
To promote cultural/regional/linguistic harmony.

The four major periods of human population growth worldwide can be traced:

An early period of hunters and gatherers
The period of the rise of agriculture.
The Industrial Revolution
The present

What happens when cities grow? Explain the harmful effects of urbanization on the following :

(a) Forests

(b) Socio-economic factors

(c) Availability of water

Ans: When cities grow,

(a) Forests
- Since cities are located near rivers and along coastlines, the expanded urban inhabitants often overtake the good agricultural land for housing, industry, etc.
- Loss of such an important and delicate habitat affects many rare and endangered species.
- Forests are cut.
(b) Socio-economic factors
- The population is redistributed.
- Automobiles/industries pollute the air.
- Poor sanitation leads to water and soil pollution
(c) Availability of water
- Due to increased urbanization, increased population and an increase in per capita water consumption.
- Careless attitude: Release of untreated sewage and other waters into rivers and lakes;
- Lowering of the water table: Due to excessive pumping of groundwater.

34. What is meant by a biosphere reserve? What are its various zones? Give the main functions of a biosphere reserve. 4

Ans: Biosphere Reserves are representative parts of natural and cultural landscapes extending over large areas of terrestrial or coastal/marine ecosystems, which are internationally recognized within UNESCO’s Man and the Biosphere Programme.

A Biosphere Reserve consists of core, buffer and transition zones.

(a) The core zone is fully protected and a natural area of the Biosphere Reserve, least disturbed by human activities. It is a legally protected ecosystem in which entry is not allowed except with permission for some special purpose. Destructive sampling for scientific investigations is prohibited.
(b) The buffer zone surrounds the core zone and is managed to accommodate a greater variety of resource use strategies and research and educational activities.
(c) The transition zone, the outermost part of the Biosphere Reserve, is an area of active cooperation between the reserve management and the local people, wherein activities like settlements, cropping, forestry, recreation and other economic activities are in harmony with the conservation goals.

The main functions of the biosphere reserves are:

Conservation: Long-term conservation of representatives, landscapes and different types of ecosystems, along with all their species and genetic resources.
Development: Encourages traditional resource use and promotes economic development, which is culturally, socially and ecologically sustainable.
Scientific research, monitoring and education- Support conservation research, monitoring, education and information exchange related to local, national and global environmental and conservation issues.

35. What do you understand by ecological efficiency? Why does the amount of energy decrease at each subsequent trophic level? If autotrophs produce 100 cal of energy, how much energy will be available to herbivores and carnivores? How can ecological efficiency be expressed? 5

Ans: The ratio between the amount of energy acquired from the lower trophic level and the amount of energy transferred from the higher trophic level is called ecological efficiency.

As per the 10% rule, related to ecological efficiency and states that the amount of energy transferred at each tropic level is only 10% of the energy of the previous tropic level. Lindman in 1942 defined these ecological efficiencies for the 1st time and proposed 10% rule, e.g. if autotrophs produce 100 cal, herbivores will be able to store 10 cal. and carnivores 1cal.

Ecological efficiency is expressed as

36. What is noise pollution? What are its sources? Give two effects of noise pollution on humans. In which ways can it be controlled? 5

Ans: Noise by definition is “sound without value” or “any noise that is unwanted by the recipient”. Such excessive noise of all kinds is called noise pollution.

Indoor sources include noise produced by radio, television, generators, electric fans, air coolers, air conditioners, different home appliances, and family conflict.
Outdoor sources of noise pollution include indiscriminate use of loudspeakers, industrial activities, automobiles, rail traffic, aeroplanes and activities such as those at marketplaces, religious, social, and cultural functions, sports and political rallies.

Effects of noise pollution on humans

Noise pollution is annoying. Noise disturbs sleep, causes hypertension (high blood pressure), emotional problems such as aggression, mental depression and annoyance. Noise pollution adversely affects the efficiency and performance of individuals.

The following steps can be taken to control or minimize noise pollution-

Road traffic noise can be reduced by better designing and proper maintenance of vehicles.
Noise abatement measures include creating noise mounds, noise attenuation walls and well-maintained roads and smooth surfacing of roads.
Retrofitting of locomotives, continuously welded rail track, use of electric locomotives, or deployment of quieter rolling stock will reduce noise emanating from trains.
Air traffic noise can be reduced by appropriate insulation and the introduction of noise regulations for takeoff and landing of aircraft at the airport.
Industrial noises can be reduced by soundproofing equipment, such as generators and areas producing a lot of noise.
Power tools, very loud music and land movers, public functions using loudspeakers, etc should not be permitted at night. Use of horns, alarms, refrigeration units, etc., is to be restricted. Use of firecrackers, which are noisy and cause air pollution, should be restricted.
A green belt of trees is an efficient noise absorber.

With reference to water pollution, explain the following terms :

(a) Point source pollution

(b) Thermal pollution

(c) Eutrophication

(d) Sewage

(e) Non-point source pollution

Ans:

(a) Point source pollution: When pollutants are discharged from a specific location, such as a drain pipe carrying industrial effluents, directly into a water body, it represents point source pollution.
(b) Thermal pollution: Discharge of hot water from power and nuclear plants increases the temperature of the water in the rivers and oceans by 10 to 15 °C above the ambient water temperature, which is called thermal pollution.
(c) Eutrophication: The discharge of domestic wastewater, agricultural return water or run-off water and many industrial effluents contribute nutrients like phosphates and nitrates. These nutrients promote excess growth of algae in water bodies (algal blooms). This is called eutrophication.
(d) Sewage: Waste water from domestic or industrial sources or from garbage dumps is generally known as sewage.
(e) Non-point source pollution includes discharge of pollutants from diffused sources or from a larger area, such as run off from agricultural fields, grazing lands, construction sites, abandoned mines and pits, roads and streets.

OPTIONAL MODULE—8A ( Water Resource Management )

37. Give two abstractive uses of water. 2

Ans: The different abstractive uses include domestic water supply, irrigation, and industrial use of water.

Irrigation: Irrigation is the most important use of water in India. Nearly 84% of the water is used only for irrigation. The total water used for irrigation is estimated as 460 BCM per annum.
Industrial use: A large amount of water is used for industrial purposes. As per the estimation of CPCB, about 30 BCM per annum is used as cooling water in thermal power plants.

38. List any four reasons for growing water shortage problem in the world. 2

Ans: Drought, expanding population, increasing irrigation demand, pollution, which is reducing the usability of water, and abuse of available water.

List four benefits of rainwater harvesting.

Ans: Some of the benefits of rainwater harvesting are as follows:

Increases water availability;
Check the declining water table.
It is environmentally friendly;
Improves the quality of groundwater through the dilution of fluoride, nitrate, and salinity;
Prevents soil erosion and flooding, especially in urban areas.

39. What is watershed? Why is the water passing through the forests relatively pure? 2

Ans: A watershed is an area through which a water body gets its water. Forests and their associated soils and litter layers are excellent filters as well as sponges, and water that passes through this system is relatively pure.

What do you understand by artificial recharge to groundwater? Mention any two methods of artificial recharge in urban areas.

Ans: Artificial recharge is a process by which excess surface water is directed into the ground – either by spreading on the surface, by using recharge wells, or by altering natural conditions to increase infiltration.

The spreading basins method involves the surface spreading of water in basins which are excavated in the existing terrain.
Recharge or injection wells are used to directly recharge water into deep water-bearing zones. Recharge wells are suitable only in areas where a thick impervious layer exists between the surface of the soil and the aquifer to be replenished.

OPTIONAL MODULE—8B ( Energy and Environment )

37. What are photovoltaic cells? Give their two uses. 2

Ans: Photovoltaic cells (solar cells), convert solar energy directly into electricity.

PV cells can be used for –

(i) domestic lighting.
(ii) street lighting.
(iii) village lighting.
(iv) water pumping.
(v) electrification.

38. Define geothermal energy. Give two examples from where this energy can be trapped in India. 2

Ans: Geothermal energy refers to energy contained in underground rock and fluids. Geothermal energy is natural heat from the interior of the Earth that can be used to generate electricity as well as to heat up buildings. In India, the Northwestern Himalayas and the western coast are considered geothermal areas.

What is a fuel cell? What is the impact of use of fuel cells on environment?

Ans: A fuel cell converts hydrogen (produced and stored) and oxygen from the air into electricity. Fuel cells are highly efficient power-generating systems that produce electricity by combining fuel (hydrogen) and oxygen in an electrochemical reaction.

Fuel cells are efficient and clean energy producers. Fuel cells have been used in space flights and are being introduced in electric vehicles to reduce urban air pollution.

39. What do you understand by energy audit? What is the role of energy auditing? 2

Ans: Energy auditing is a systematic approach to monitoring industrial energy consumption and identifying sources of energy waste. It consists of activities that seek to identify conservation opportunities before conducting or developing any energy-saving program.

The most important role of energy auditing is to identify the areas of energy consumption and to find the overuse for assessing the opportunity of saving energy.

What do you understand by energy-efficient new towns? How can such towns be created?

Ans: Energy-efficient new towns

Effective use of land could prove to be a good way of energy conservation. The design of the town should be such that developmental densities should be highest towards the centre of the town, which is served by municipal water and sewer. Outlying areas should have many fewer constructions.

A branded programme can be created with a title and logo to imprint the conservation message on all township communities and documents.
The best way to conserve energy is to switch off the lights while leaving the room and shut down the computers when not in use. When appliances are not in use, they should be unplugged.
Lower the thermostats in the winter and raise them in the summer.
Household and business wastes should be recycled. It will positively result in energy conservation.
Light bulbs should be replaced with the energy-efficient compact fluorescent bulbs as they use 75% less energy and last up to ten times longer than standard incandescent bulbs.

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