UPSC Essentials | Daily subject-wise quiz : Environment and Geography MCQs on Nazca plate, Methane and more (Week 87)

1. It is less effective than carbon dioxide at trapping heat.

2. Wetlands release methane as soil microbes break down carbon-rich plant matter.

3. From 2020 to 2022, methane concentrations in the atmosphere have decreased.

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

Explanation

— Tropical wetlands emit enormous amounts of methane, jeopardising global attempts to address climate change. According to research, rising temperatures and heavy rains are increasing methane emissions, which were previously underestimated in scientific models and national climate plans.

— Methane, a strong greenhouse gas, traps heat 80 times more effectively than carbon dioxide during a 20-year period. Hence, statement 1 is not correct.

— Wetlands emit methane as soil bacteria break down carbon-rich plant matter, a process accelerated by rising temperatures and increased wetland area due to floods. Hence, statement 2 is correct.

— From 2020 to 2022, methane concentrations in the atmosphere reached their highest levels since 1980. According to studies, tropical regions are mostly responsible for the increase, with the Congo, Southeast Asia, the Amazon, and southern Brazil contributing significantly. Nature Climate Change data found that wetland emissions had exceeded worst-case forecasts by 500,000 tonnes per year over the last two decades. Hence, statement 3 is not correct.

Therefore, option (a) is the correct answer.

QUESTION 2

Consider the following:

1. Algae

2. Jellyfish

3. Crustaceans

4. Sea stars

How many of the above can produce their own light?

(a) Only one

(b) Only two

(c) Only three

(d) All four

Explanation

— Bioluminescence is the ability of a living creature to generate and radiate light. This phenomenon is unusual in terrestrial ecosystems but prevalent in marine environments.

— Many marine animals, including bacteria, algae, jellyfish, worms, crabs, sea stars, fish, and sharks, can create their own light. Deep-living and planktonic creatures exhibit higher luminescence than shallow species. Furthermore, the appearance of bioluminescent light varies depending on the environment and creature in which it is present.

— According to NOAA, bioluminescence is the product of an enzyme reaction. An enzyme accelerates a chemical reaction by assisting a substrate in reacting. The enzyme is reused in the process rather than being converted into another molecule.

— Luciferase is the enzyme that causes bioluminescent reactions. The varied substrates are known as luciferins. Luciferase catalyses the chemical reaction between luciferins and oxygen. During this chemical reaction, the luciferin molecule is oxidised, producing light and a new, inactive molecule called oxyluciferin.

Therefore, option (d) is the correct answer.

QUESTION 3

With reference to the elephants counting in India, consider the following:

1. In 2023, the “indirect dung count method” was introduced in the southern states.

2. Until 2012, elephants were counted in India by the “total direct count” method, which means a simple head count of elephants that were sighted.

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

Explanation

— The Environment Ministry has shelved its elephant census report, ‘Status of Elephant in India 2022-23’, blaming a delay in the Northeast census. The report on the present status of the national heritage animal in the rest of India has been printed, but it will not be released until at least June 2025.

— The leaked research reveals a severe reduction in elephant populations in the east-central and southern areas. The decline is most pronounced in Southern West Bengal (84%), Jharkhand (64%), Odisha (54%), and Kerala (51%).

— According to the paper, “mushrooming developmental projects” like “unmitigated mining and linear infrastructure construction” pose a severe threat to the species.

— However, the new counting methods may not entirely explain the decline in elephant populations. “The new method based on DNA profiling has not brought down the numbers in the northern (Shivalik Hills and Gangetic Plain) landscape where the latest figure (2,062) closely aligns with the outcome of the previous census (2,096),” a Bengaluru-based wildlife biologist observed. “So, the drastic fall in numbers elsewhere can’t be dismissed as a fallout of methodological variation,” the evolutionary biologist explained.

— Until 2002, elephants in India were tallied using the “total direct count” approach, which involves a basic head count of elephants that are spotted. According to the most recent census report, this strategy has “limited or no scientific basis for large landscapes or populations”. Hence, statement 2 is not correct.

— In 2002, the “indirect dung count method” was implemented in the Southern States. Enumerators strolled across the forest in predetermined straight lines, counting elephant droppings and measuring the “dung decay rate”. The data were extrapolated to estimate elephant density in a given area by taking elephant “defecation rate” into account. Hence, statement 1 is not correct.

Therefore, option (d) is the correct answer.

QUESTION 4

The Nazca plate is located in the region of:

(a) Central Asia

(b) South-east Asia

(c) Northern Europe

(d) South America

Explanation

— Hundreds (if not thousands) of ancient geoglyphs can be found on the desolate Nazca Pampa, around 400 kilometres south of Lima in Peru.

— The Nazca Lines were found by coincidence in the mid-1920s. It took nearly a century to uncover approximately 430 of these geoglyphs. Then, in under six months, artificial intelligence (AI) sparked a surge of 303 new discoveries.

— Geoglyphs are motifs formed on the ground by manipulating surface stones, soil, and gravel. The ones in Nazca, the oldest of which is about 2,000 years old, were constructed by removing rocks and earth to form “negative” images. The desert’s topsoil has oxidised to a deep rust colour, making the furrows stand out from the surrounding landscape. And because the location receives almost no rain and little wind, the patterns have generally avoided erosion and survived for thousands of years.

— The Nazca plate, sometimes known as the Nasca plate, is an oceanic tectonic plate in the eastern Pacific Ocean basin off South America’s west coast. It was named after the Nazca region in southern Peru.

Therefore, option (d) is the correct answer.

QUESTION 5

With reference to the solar eclipse, consider the following statements:

1. Total solar eclipse is very common and it happens every two months.

2. A solar eclipse takes place when the Moon and Sun are aligned on the same side of Earth.

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

Explanation

— A solar eclipse takes place when the Moon moves in the middle of Earth and the Sun. The Moon blocks the light of the Sun, either fully or partially, which casts a huge shadow on some parts of the world.

— There are four different types of solar eclipses, including total solar eclipse, annual solar eclipse, partial solar eclipse, and hybrid solar eclipse.

— A solar eclipse is witnessed only during the new moon.

— It takes place when the Moon and Sun are aligned on the same side of Earth. Hence, statement 2 is correct.

— However, the solar eclipse does not happen every month. It takes place only between two to five times annually.

— The Moon does not orbit Earth in the same plane as the Earth orbits the Sun. In fact, the Moon is tilted by about five degrees with respect to Earth. As a result, most of the time when the Moon is in between the Sun and Earth, its shadow is either too high or too low to fall on the Earth.

— There can be between two and five solar eclipses every year, total eclipses only happen about once every 18 months or so. Hence, statement 1 is not correct.

Therefore, option (b) is the correct answer.

Previous Daily Subject-Wise-Quiz

Daily Subject-wise quiz — History, Culture, and Social Issues (Week 87)

Daily subject-wise quiz — Polity and Governance (Week 87)

Daily subject-wise quiz —  Science and Technology (Week 87)

Daily subject-wise quiz — Environment and Geography (Week 86)

Daily subject-wise quiz — Economy (Week 86)

Daily subject-wise quiz – International Relations (Week 86)

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