UPSC 2023 Environment and Ecology Questions with Answers

Explanation

Marsupials are a group of mammals commonly referred to as pouched mammals, such as kangaroos and wallabies. These animals are characterized by giving birth to underdeveloped young, which then continue their development in the mother’s pouch (marsupium). They give live birth, but they do not have long gestation times like placental mammals. The pouch provides protection and access to nourishment during this critical growth stage. Statement-I is correct: Marsupials can be observed in regions spanning Australia, Papua New Guinea, and South America. They are not naturally found in India. Examples of marsupials include kangaroos, wallabies, wombats, opossums, bandicoots, and koalas. Statement-II is incorrect: These creatures predominantly inhabit arid and semi-arid areas, and they are not restricted solely to montane grasslands. Marsupials are highly adaptable and thrive in a variety of habitats, including forests, deserts, grasslands. Additionally, they coexist with predators like dingoes, eagles, and foxes in their natural environments.

Explanation

Option 1 is incorrect: Lion-tailed Macaque, also referred to as the wanderoo, inhabits the upper canopy of tropical evergreen rainforests and monsoon forests across various elevations. This species is endemic to the Western Ghats. They are diurnal which means it is active during the day and not nocturnal. IUCN Red List: Endangered Option 2 is correct: Malabar Civet is endemic to the Western Ghats of India. It is listed as Critically Endangered on the IUCN Red List. The Malabar civet is considered nocturnal and so elusive that little is known about its biology and ecology apart from habitat use. IUCN Red List: Critically Endangered Option 3 is incorrect: The Sambar, a large deer native to the Indian subcontinent and Southeast Asia, is crepuscular, active during twilight (morning and evening), and occasionally after sunset. Males are mostly solitary while females form small herds of up to 16 individuals. IUCN Red List: Vulnerable

Explanation

The waggle dance is a unique form of communication performed by honey bees (Apis mellifera) to convey information about the direction and distance of food sources, water, or potential nesting sites to other members of their hive. Worker honeybees, all of which are females, constitute the only bees typically observed flying outside the hive by the general populace. Bees perform two distinct types of dances: The Round Dance and the Tail-wagging or Waggle Dance. The waggle dance of honeybees has long been recognized as a behaviour that communicates in-formation about resource location from a foraging worker to her nest mates.

Explanation

Microorganisms are classified into three primary groups on the basis of their preferred range of temperature:

Psychrophiles (cold-loving microbes) Mesophiles (moderate - temperature - loving microbes) Thermophiles (heat-loving microbes).

Statement 1 is correct: Hyperthermophiles such as Pyrobolus and Pyrodictium can grow at temperatures exceeding 100°C especially in high-pressure environments like deep-sea hydrothermal vents.

Statement 2 is correct: Psychrophiles such as Colwellia psy-chrerythraea and Pseudomonas syringae can grow at temperatures as low as -10°C and remain metabolically active even at -20°C in environments like Arctic permafrost, deep-sea polar waters, and glacial ice. These microbes produce cryoprotectants such as antifreeze proteins to prevent ice crystal formation in-side their cells.

Statement 3 is correct: Acidophiles such as Ferroplasma acidar-manus and Acidithiobacillus ferrooxidans thrive in environments with pH as low as 0.5, such as acidic hot springs, acid mine drain-ages, and volcanic sulfur pools. These microbes have evolved mechanisms to pump out excess protons (H ions) to maintain internal pH stability. Some acidophiles like Thermoplasma lack a cell wall but possess specialized membrane structures to withstand extreme acidity.

Explanation

Orangutans are highly intelligent great apes known for their tool-using abilities. They have been observed breaking off small branches and using them as tools to scrape insects from holes in trees or logs. This behavior demonstrates their advanced cognitive skills, problem-solving abilities, and adaptability in foraging. None of the other listed animals.

Explanation

Statement 1 is correct: In India, Biodiversity Management Committees (BMCs) are established at the local level under the Biological Diversity Act, 2002. The National Biodiversity Authority (NBA) and State Biodiversity Boards (SBBs) work with BMCs to regulate access to biological resources and traditional knowledge, ensuring compliance with the Nagoya Protocol.

Statement 2 is correct: Biological Diversity Act, 2002 empowers BMCs to determine Access and Benefit Sharing (ABS) mechanisms for biological resources found within their jurisdiction. They can levy collection fees on any person or entity accessing biological resources for commercial use.

Explanation

Hydrofluorocarbons (HFCs) are a climate "Super-Pollutant" - Greenhouse gases with hundreds to thousands of times the heat-trapping power of carbon dioxide (CO₂). HFCs are synthetic gases used in air conditioning systems, aerosol propellants, foam- blowing agents, solvents, and flame retardants. These gases were first developed as alternatives to ozone- depleting chemicals, but after their rollout, it was learned that their release to the atmosphere during manufacturing processes and leakage during use, servicing, and retirement/replacement of equipment poses a grave threat to our climate. Lubricants are typically based on oils and synthetic esters, not HFCs.

Explanation

Statement 1 is correct: Mercury is used in Artisanal Small-Scale Gold Mining (ASGM). The majority of the mercury emissions associated with the ASGM sector come from the burning of mercury-gold amalgam, which is responsible for 38% of all anthropogenic mercury emissions to the atmosphere.

Statement 2 is correct: Mercury is released into the atmosphere via the burning of coal and other fossil fuels. Because coal has far higher mercury content than other fossil fuels, coal-fired power stations frequently produce more mercury pollution than power plants that burn other fossil fuels.

Statement 3 is incorrect: The Occupational Safety and Health Administration (OSHA) considers mercury vapor concentrations above 0.01 mg/m³ hazardous for prolonged exposure, with an acceptable limit of 0.1 mg/m³ based on an 8-hour time-weighted average. Both American Conference of Governmental Industrial Hygienists (ACGIH) and National Institute for Occupational Safety and Health (NIOSH) recommend even lower exposure levels to minimize health risks.

Explanation

Statement-I is correct: According to the United Nations’ World Water Development Report 2022, India extracts more than a quarter of the world’s groundwater withdrawal each year. This indicates that India has a significant reliance on groundwater resources for various purposes, including irrigation, drinking water, and industrial use. Statement-II is not correct: Approximately 89% of India’s groundwater is utilised for irrigation purposes. The primary portion of the total groundwater extracted in India serves irrigation needs rather than being allocated for drinking and sanitation purposes. Only a small portion of groundwater is utilized for domestic and industrial purposes.

Explanation

Statement I is correct: Carbon markets are trading systems in which carbon credits are sold and bought. Companies or individuals can use carbon markets to compensate for their greenhouse gas emissions by purchasing carbon credits from entities that remove or reduce greenhouse gas emissions. One tradable carbon credit equals one tonne of carbon dioxide or the equivalent amount of a different greenhouse gas reduced, sequestered or avoided. Carbon markets, including compliance and voluntary markets, are widely recognized as effective tools for reducing greenhouse gas emissions. They incentivize emission reductions by allowing entities to trade carbon credits, making them a key mechanism in global climate action.

Statement II is correct: Carbon markets help reduce green-house gas emissions by assigning value to carbon and creating a market for trading carbon credits, which represent the right to emit a certain amount of greenhouse gases. They enable more efficient allocation of emission reduction efforts and facilitate the exchange of allowances between public and private entities, of-ten involving financial transactions. Carbon markets can generate revenue for governments through mechanisms like the sale of emission allowances in compliance markets. However, this is not their primary purpose, as carbon markets primarily facilitate trading between private entities to reduce emissions efficiently.