UPSC IAS 2020 PRELIMS DETAILED EXPLANATIONS OF ENVIRONMENT QUESTIONS

Q 1. Which of the following are the reasons/factors for exposure to benzene pollution ?
1.Automobile exhaust
2.Tobacco smoke
3.Wood burning
4.Using varnished wooden furniture
5.Using products made of polyurethane
Select the correct answer using the code given below :
(a) 1, 2 and 3 only
(b) 2 and 4 only
(c) 1, 3 and 4 only
(d) 1, 2, 3, 4 and 5

ANSWER : (d) 1, 2, 3, 4 and 5

Where benzene is found and how it is used?

1 . Natural sources of benzene include volcanoes and forest fires.
2 . Benzene is also a natural part of crude oil, gasoline, and cigarette smoke.
3 . Some industries use benzene to make other chemicals that are used to make plastics, resins, and nylon and synthetic fibers.
4 . Benzene is also used to make some types of lubricants, rubbers, dyes, detergents, drugs, and pesticides.

How we could be exposed to benzene?

1 . Outdoor air contains low levels of benzene from tobacco smoke, gas stations, motor vehicle exhaust, and industrial emissions.
2 . Indoor air generally contains levels of benzene higher than those in outdoor air. The benzene in indoor air comes from products that contain benzene such as glues, paints, furniture wax, and detergents.
3 . The air around hazardous waste sites or gas stations can contain higher levels of benzene than in other areas.
4 . Benzene leaks from underground storage tanks or from hazardous waste sites containing benzene can contaminate well water.
5 . People working in industries that make or use benzene may be exposed to the highest levels of it.
6 . A major source of benzene exposure is tobacco smoke.

Q 2 . Consider the following pairs:

International agreement/set-up :  Subject

1 . Alma-Ata Declaration : Healthcare of the people
2. Hague Convention : Biological and chemical weapons
3. Talanoa Dialogue : Global climate change
4. Under2 Coalition : Child rights

Which of the pairs given above is/ are correctly matched?

(a) 1 and 2 only
(b) 4 only
(c) 1 and 3 only
(d) 2, 3 and 4 only

ANSWER : (c) 1 and 3 only

Alma-Ata Declaration

The Declaration of Alma-Ata was adopted at the International Conference on Primary Health Care (PHC), Almaty (formerly Alma-Ata), Kazakhstan  6–12 September 1978. It expressed the need for urgent action by all governments, all health and development workers, and the world community to protect and promote the health of all people. It was the first international declaration underlining the importance of primary health care.

Hague Convention

The Hague Convention on the Civil Aspects of International Child Abduction or Hague Abduction Convention is a multilateral treaty developed by the Hague Conference on Private International Law (HCCH) that provides an expeditious method to return a child internationally abducted by a parent from one member country to another.

Talanoa Dialogue

The Talanoa Dialogue is a process designed to help countries implement and enhance their Nationally Determined Contributions by 2020. The Dialogue was mandated by the Parties to the United Nations Framework Convention for Climate Change to take stock of the collective global efforts to reduce the emissions of greenhouse gases, in line with the goals of the Paris Agreement, which is to limit the rise in average global temperature to 2°C above pre-industrial levels, and to pursue efforts to limit the increase to 1.5°C

Under2 Coalition

The Under2 Coalition is a coalition of subnational governments that aims to achieve greenhouse gases emissions mitigation. It started as a memorandum of understanding, which was signed by twelve founding jurisdictions on May 19, 2015 in Sacramento, California. Although it was originally called the Under2 MOU, it became known as the Under2 Coalition in 2017.

Q 3 . What are the advantages of fertigation in agriculture?
1 . Controlling the alkalinity of irrigation water is possible.
2 . Efficient application of Rock Phosphate and all other phosphatic fertilizers is possible.
3 . Increased availability of nutrients to plants is possible.
4 . Reduction in the leaching of chemical nutrients is possible.
Select the correct answer using the code given below:
(a) 1, 2 and 3 only
(b) 1, 2 and 4 only
(c) 1, 3 and 4 only
(d) 2, 3 and 4 only

ANSWER : (c) 1, 3 and 4 only

Phosphate rock cannot be used as a fertiliser because it is insoluble but it can be used to make fertilisers.

The benefits of fertigation methods over conventional or drop-fertilizing methods include:

1 . Increased nutrient absorption by plants.
2 . Accurate placement of nutrient, where the water goes the nutrient goes as well.
3 . Ability to “micro dose”, feeding the plants just enough so nutrients can be absorbed and are not left to be washed down to storm water next time it rains.
4 . Reduction of fertilizer, chemicals, and water needed.
5 . Reduced leaching of chemicals into the water supply.
6 . Reduced water consumption due to the plant’s increased root mass’s ability to trap and hold water.
7 . Application of nutrients can be controlled at the precise time and rate necessary.
8 . Minimized risk of the roots contracting soil borne diseases through the contaminated soil.
9 . Reduction of soil erosion issues as the nutrients are pumped through the water drip system.
10 . Leaching is decreased often through methods used to employ fertigation.
11 . Controlling the alkanity of irrigation water is possible.

Q 4 . With reference to India’s Desert National Park, which of the following statements are correct?
1 . It is spread over two districts.
2 . There is no human habitation inside the Park.
3 . It is one of the natural habitats of Great Indian Bustard.
Select the correct answer using the code given below;

(a) 1 and 2 only
(b) 2 und 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

ANSWER : (c) 1 and 3 only

Desert National Park (DNP)

The Desert National Park (DNP) covers an area of 3162 km² of which 1900 km² is in Jaisalmer district and remaining 1262 km² is in Barmer district of Rajasthan State. The area falls in the extreme hot and arid region of very low rainfall zone (<100mm) of the country.

The DNP is barren with several sand dunes and a few hills in the north-western region. The Park forms a vast sandy and undulating terrain.

The vegetation of major part of the arid region of the Thar falls under thorn forest type . Khejri Prosopis cineraria is commonly found, which is revered and protected by the local communities specially the ‘Bishnois’. The vegetation of DNP is quite sparse with open grassland, throny bushes, plantation and dunes as the broad habitat types.

The biota of Thar has both mesic and desert elements owing to location of the Thar in the Saharo-Tharian Basin. 69% of herpetofauna and 54% of mammalian fauna represent the Sahraian affiliation.

The Thar desert is the most thickly populated desert in the world with an average density of 83 persons/km² (compared to 7km² of other deserts) . However, the human population within the DNP is low (4-5 persons per km²). There are 73 villages and also settlements or Dhanis existing within the Park. These communities have inhabited this area for hundreds of years and with their rich culture and tradition they are an integral part of this ecosystem.

The endangered great Indian bustard is a magnificent bird found in relatively fair numbers. It migrates locally in different seasons.

Q 5 . Among the following Tiger Reserves, which one has the largest area under “Critical TigerHabitat”?
(a) Corbett
(b) Ranthambore
(c) Nagarjunsagar-Srisailam
(d) Sunderbans

ANSWER : (c) Nagarjunsagar-Srisailam

Corbett  – Area of the core / critical tiger habitat (In Sq. Kms.) –  821.99
Ranthambore – Area of the core / critical tiger habitat (In Sq. Kms.) – 1113.364
Nagarjunsagar-Srisailam – Area of the core / critical tiger habitat (In Sq. Kms.) – 2595.72
Sunderbans –Area of the core / critical tiger habitat (In Sq. Kms.) – 1699.62

Q 6 . If a particular plant species is placed under Schedule VI of The Wildlife Protection Act, 1972, what is the implication?
(a) A licence is required to cultivate that plant.
(b) Such a plant cannot be cultivated under any circumstances.
(c) It is a Genetically Modified crop plant.
(d) Such a plant is invasive and harmful to the ecosystem.

ANSWER : (b) Such a plant cannot be cultivated under any circumstances.

Cultivation, Collection, extraction, trade, etc. of Plants and its derivatives listed in schedule 6 are prohibited. Red Vanda, blue Vanda, kuth, pitcher plant, beddomes cycad and ladies slipper orchid are the list of plants listed in schedule 6.

Q 7 . What is/are the advantage/advantages of zero tillage in agriculture?
1 . Sowing of wheat is possible without burning the residue of previous crop.
2 . Without the need for nursery of rice saplings, direct planting of paddy seeds in the wet soil is possible.
3 . Carbon sequestration in the soil is possible.

Select the correct answer using the code given below:

(a) 1 and 2 only
(b) 2 and 3 only
(c) 3 only
(d) 1, 2 and 3

ANSWER : (d) 1, 2 and 3

Advantages of zero tillage

1 . Reduction in the crop duration and thereby early cropping can be obtained to get higher yields.
2 . Reduction in the cost of inputs for land preparation and therefore a saving of around 80%.
3 . Residual moisture can be effectively utilized and number of irrigations can be reduced.
4 . Dry matter and organic matter get added to the soil.
5 . Environmentally safe – Greenhouse effect will get reduced due to carbon sequestration.
6 . No tillage reduces the compaction of the soil and reduces the water loss by runoff and prevent soil erosion.
7 . As the soil is intact and no disturbance is done, No Till lands have more useful flora and fauna.
8 . Zero tillage proves better for direct-seeded rice, maize, soybean, cotton, pigeonpea, mungbean, clusterbean, pearlmillet during kharif season and wheat, barley, chickpea, mustard and lentil during rabi season.
9 . Wheat sowing after rice can be advanced by 10-12 days by adopting this technique compared to conventionally tilled wheat, and wheat yield reduction caused by late sowing can be avoided.
10 . ZT provides opportunity to escape wheat crop from terminal heat stress.
11 . Zero tillage reduces cost of cultivation by nearly Rs 2,500-3,000/ha through reduction in cost of land preparation, and reduces diesel consumption by 50-60 litres per hectare.
12 . Zero tillage reduces water requirement of crop and the loss of organic carbon by oxidation.
13 . Zero tillage reduces Phalaris minor problem in wheat.
14 . The carbon status of soil is significantly enhanced in surface soil (0-5 cm), particularly under crop residue retention with zero tillage.

Q 8 . According to India’s National Policy on Biofuels, which of the following can be used as raw materials for the production of biofuels?
1 . Cassava
2 . Damaged wheat grains
3 . Groundnut seeds
4 . Horse gram
5 . Rotten potatoes
6 . Sugar beet

Select the correct answer using the code given below:

(a) 1,2,5 and 6 only
(b) 1,3,4 and 6 only
(c) 2,3,4 and 5 only
(d) 1,2,3,4,5 and 6

ANSWER : (a) 1,2,5 and 6 only

The Policy expands the scope of raw material for ethanol production by allowing use of Sugarcane Juice, Sugar containing materials like Sugar Beet, Sweet Sorghum, Starch containing materials like Corn, Cassava, Damaged food grains like wheat, broken rice, Rotten Potatoes, unfit for human consumption for ethanol production.

Q 9 . Which one of the following statement best describes the term ‘Social Cost of Carbon’? It is a measure, in monetary value, of the
(a) long-term damage done by a tonne of COշ emissions in a given year.
(b) requirement of fossil fuels for a country to provide goods and services to its citizens, based on the burning of those fuels.
(c) efforts put in by a climate refugee to adapt to live in a new place.
(d) contribution of an individual person to the carbon footprint on the planet Earth.

ANSWER : (a) long-term damage done by a tonne of COշ emissions in a given year.

The social cost of carbon (SCC) is an estimate, in dollars, of the economic damages that would result from emitting one additional ton of greenhouse gases into the atmosphere. The SCC puts the effects of climate change into economic terms to help policymakers and other decisionmakers understand the economic impacts of decisions that would increase or decrease emissions.

The social cost of carbon is a calculation to focus on taking corrective measures on climate change which can be deemed a form of market failure.

Q 10 . With reference to solar water pumps, consider the following statements:
1 . Solar power can be used for running surface pumps and not for submersible pumps.
2 . Solar power can be used for running centrifugal pumps and not the ones with piston.

Which of the statements given above is/are correct?

(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

ANSWER : (d) Neither 1 nor 2

Pumps normally used as solar pump:

1 . Surface mounted centrifugal pump set (Similar to conventional pump)
2 . Submersible pump set
3 . Helical rotor pump (Robust, only one turning part)
4 . Piston (diapraghm) pump (Complex, lot of moving parts, require oil lubrication)

The system operates on power generated using solar PV (photovoltaic) system. The photovoltaic array converts the solar energy into electricity, which is used for running the motor pump set. The pumping system draws water from the open well, bore well, stream, pond, canal etc.

Q 11 . In the context of India, which of the following is/are considered to be practice(s) of eco-friendly agriculture?
1 . Crop diversification
2 . Legume intensification
3 . Tensiometer use
4 . Vertical farming

Select the correct answer using the code given below:

(a) 1,2 and 3 only
(b) 3 only
(c) 4 only
(d) 1,2,3 and 4

ANSWER : (d) 1,2,3 and 4

Q 12 . What is the use of biochar in farming ?
1 . Biochar can be used as a part of the growing medium in vertical farming.
2 . When biochar is a part of the growing medium, it promotes the growth of nitrogen-fixing microorganisms.
3 . When biochar is a part of the growing medium, it enables the growing medium to retain water for longer time.

Which of the statements given above is/are correct ?

(a) 1 and 2 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3

ANSWER : (d) 1, 2 and 3

Q 13 . Consider the following statements :
1 . Coal ash contains arsenic, lead and mercury.
2 . Coal-fired power plants release sulphur dioxide and oxides of nitrogen into the environment.
3 . High ash content is observed in Indian coal.

Which of the statements given above is/are correct ?

(a) 1 only
(b) 2 and 3 only
(c) 3 only
(d) 1, 2 and 3

ANSWER : (d) 1, 2 and 3

Q 14 . In rural road construction, the use of which of the following is preferred for ensuring environmental sustainability or to reduce carbon footprint ?
1 . Copper slag
2 . Cold mix asphalt technology
3 . Geotextiles
4 . Hot mix asphalt technology
5 . Portland cement

Select the correct answer using the code given below :

(a) 1, 2 and 3 only
(b) 2, 3 and 4 only
(c) 4 and 5 only
(d) 1 and 5 only

ANSWER : (a) 1, 2 and 3 only

Q 15 . Which of the following are the most likely places to find the musk deer in its natural habitat ?
1 . Askot Wildlife Sanctuary
2 . Gangotri National Park
3 . Kishanpur Wildlife Sanctuary
4 . Manas National Park

Select the correct answer using the code given below

(a) 1 and 2 only
(b) 2 and 3 only
(c) 3 and 4 only
(d) 1 and 4 only

ANSWER : (a) 1 and 2 only

TO BE CONTINUED ………….