Solved Questions on Environment and Ecology (Part 4)

Questions 11-20: Correct Responses, Explanations, and Background Information

Question 11

11. With reference to the planet Earth, consider the following statements: 

1. Rain forests produce more oxygen than that produced by oceans.  

2. Marine phytoplankton and photo synthetic bacteria produce about 50% of the world's oxygen.  

3. Well-oxygenated surface water contains several folds higher oxygen than that in atmospheric air.  

Which of the statements given above is/are correct?  

(a) 1 and 2 only

(b) 2 only  

(c) 1 and 3 only

(d) None of the above statements is correct 

Correct Response: B

Explanation:

·      About 50% of the oxygen production on Earth comes from the ocean.

·      Most of this oxygen is produced by oceanic plankton.

·      Rain forests produce less oxygen than that produced by oceans.

·      Even though dissolved oxygen is highest at the surface of water, there is still far less oxygen in the water than is found in the air.

Thus, only Statement II is correct.

Question 12

12. Consider the following statements:  

1. India has joined the Minerals Security Partnership as a member. 

2. India is a resource-rich country in all the 30 critical minerals that it has identified. 

3. The Parliament in 2023 has amended the Mines and Minerals (Development and Regulation) Act, 1957 empowering the Central Government to exclusively auction mining lease and composite license for certain critical minerals.  

Which of the statements given above are correct?  

(a) 1 and 2 only

(b) 2 and 3 only

(c) 1 and 3 only

(d) 1,2, and 3

Correct Response: C

Explanation and Background Information:

·      India joined the US-led Minerals Security Partnership (MSP) in June 2023 during Prime Minister Narendra Modi's visit to the US.  

·      India is a not rich in all the 30 critical minerals that it has identified. 

·      The Mines and Minerals (Development and Regulation) Amendment Act, 2023 introduced major reforms in the mining sector including:

o   Empowering the Central Government to exclusively auction mineral concessions for critical minerals. Revenue from these auctions will accrue to concerned State Government.

o   Introducing exploration licence for deep-seated and critical minerals

Thus, Statements I and II are correct.

Question 13

13. Consider the following statements: 

Statement I: Circular economy reduces the emissions of greenhouse gases.  

Statement II: Circular economy reduces the use of raw materials as inputs.  

Statement III: Circular economy reduces wastage in the production process.  

Which one of the following is correct in respect of the above statements?  

(a) Both Statement II and Statement III are correct and both of them explain Statement I.  

(b) Both Statement II and Statement III are correct but only one of them explains Statement I.  

(c) Only one of the Statements II and III is correct and that explains Statement I.  

(d) Neither Statement II nor Statement III is correct. 

Correct Response: A

Explanation and Background Information: Circular economy aims to minimize waste and promote a sustainable use of natural resources, through smarter product design, longer use, recycling and more, as well as regenerate nature. Consequently, it also generates less emissions.

Thus, both Statement II and Statement III are correct and both of them explain Statement I.  

Question 14

14. Consider the following statements:

1. Without the atmosphere, temperature would be well below freezing point everywhere on the Earth's surface. 

2. Heat absorbed and trapped by the atmosphere maintains our planet's average temperature. 

3. Atmosphere's gases, like carbon dioxide, are particularly good at absorbing and trapping radiation. 

Which of the statements given above are correct?  

(a) 1 and 3 only  

(b) 1 and 2 only  

(c) 1,2, and 3

(d) 2 and 3 only

Correct Response: C

Question 15

15. Artificial way of causing rainfall to reduce air pollution makes use of

(a) Silver iodide and potassium iodide  
(b) Silver nitrate and potassium iodide  
(c) Silver iodide and potassium nitrate  
(d) Silver nitrate and potassium chloride 

Correct Response: A

Explanation and Background Information: Artificial way of causing rainfall is called cloud seeding.

According to Wikipedia, cloud seeding is undertaken by dispersing substances into the air that serve as cloud condensation or ice nuclei. Common agents include silver iodide, potassium iodide, and dry ice, with hygroscopic materials like table salt gaining popularity due to their ability to attract moisture.

Question 16

16. Which organization has enacted the Nature Restoration Law (NRL) to tackle climate change and biodiversity loss?  

(a) The European Union  
(b) The World Bank  
(c) The Organization of Economic Cooperation and Development 
(d) FAO  

Correct Response: A

Explanation and Background Information: The Nature Restoration Law or Regulation is the first continent-wide, comprehensive law of its kind. It is a key element of the European Union’s Biodiversity Strategy, which sets binding targets to restore degraded ecosystems, particularly those with the most potential to capture and store carbon and to prevent and reduce the impact of natural disasters.

The Regulation aims to restore ecosystems, habitats and species across the EU’s land and sea areas to

1. enable the long-term and sustained recovery of biodiverse and resilient nature

2. contribute to achieving the EU’s climate mitigation and climate adaptation objectives

3. meet international commitments.

The Nature Restoration Law entered into force on August 18, 2024.

Question 17

17. Consider the following statements:  

Statement I: Of the two major ethanol producers in the world, i.e., Brazil and the United States of America, the former produces more ethanol than the latter.  

Statement II: Unlike in the United States of America where corn is the principal feedstock for ethanol production, sugarcane is the principal feedstock for ethanol production in Brazil  

Which one of the following is correct in respect of the above statements?   

(a) Both Statement I and Statement II are correct, and Statement II explains Statement I.   

(b) Both Statement I and Statement II are correct, but Statement II does not explain Statement I.   

(c) Statement I is correct, but Statement II is not correct.   

(d) Statement I is not correct, but Statement II is correct.

Correct Response: D

Explanation and Background Information: While the US produces about 28 billion gallons of ethanol, Brazil is second with 15 billion gallons. The US mostly makes ethanol from corn, while Brazil uses primarily sugarcane.

Thus, Statement I is not correct, and Statement II is correct.

Question 18

18. The World Bank warned that India could become one of the first places where wet-bulb temperatures routinely exceed 35 °C. Which of the following statements best reflect(s) the implication of the above-said report?  

1. Peninsular India will most likely suffer from flooding, tropical cyclones and droughts. 

2. The survival of animals including humans will be affected as shedding of their body heat through perspiration becomes difficult.  

Select the correct answer using the code given below.   

(a) 1 only   

(b) 2 only   

(c) Both 1 and 2 

(d) Neither 1 nor 2

Correct Response: B?

Explanation and Background Information:

In 2023, the World Bank released a report entitled “Climate Investment Opportunities in India's Cooling Sector” which said:

Currently, in India, the wet bulb temperature during the worst heat waves rarely, if ever, exceeds 32°C. However, climate models project that these temperatures could exceed the survivability threshold (that is, 35°C) at a few locations in the Chota Nagpur Plateau and North-Eastern India under future climate scenarios of the IPCC’s Fifth Assessment Report.

The report did not say anything about peninsular India. In any case, climate change will lead to flooding and droughts all over India and cyclones in all coastal areas.

Hence, option B could be correct. Check on the UPSC site when they release the Answer Key in due course.

Question 19

19. Consider the following statements about PM Surya Ghar Muft Bijli Yojana: 

1. It targets installation of one crore solar rooftop panels in the residential sector.  

2. The Ministry of New and Renewable Energy aims to impart training on installation, operation, maintenance and repairs of solar_rooftop systems at grassroot levels. 

3. It aims to create more than three lakhs skilled manpower through fresh skilling, and upskilling, under scheme component of capacity building.   

Which of the statements given above are correct?   

(a) 1 and 2 only   

(b) 1 and 3 only   

(c) 2 and 3 only   

(d) 1, 2, and 3

Correct Response: D

Explanation: All the statements reflect the details of PM Surya Ghar Muft Bijli Yojana.

Question 20

20. Consider the following activities:   

1. Production of crude oil 

2. Refining, storage, and distribution of petroleum 

3. Marketing and sale of petroleum products 

4. Production of natural gas 

How many of the above activities are regulated by the Petroleum and Natural Gas Regulatory Board (PNGRB) in India? 

(a) Only one 

(b) Only two 

(c) Only three 

(d) All four 

Correct Response: B

Explanation and Background Information: According to the website of PNGRB:

·      The Petroleum and Natural Gas Regulatory Board (PNGRB) was constituted under the Petroleum and Natural Gas Regulatory Board Act, 2006.

·      The Act provides for the establishment of PNGRB to protect the interests of consumers and entities engaged in specified activities relating to petroleum, petroleum products and natural gas and to promote competitive markets and for matters connected therewith or incidental thereto.

·      The Board has also been mandated to regulate the refining, processing, storage, transportation, distribution, marketing and sale of petroleum, petroleum products and natural gas excluding production of crude oil and natural gas so as and to ensure uninterrupted and adequate supply of petroleum, petroleum products and natural gas in all parts of the country.

The production of crude oil is not under the purview of the Board.

Thus, option B is correct.

(Note: Questions 1-10 were covered in earlier posts.)

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