Environment PYQs topic-wise — UPSC Prelims

Statement 1 is sound, but statement 2 reverses the role of technology. A tracking device reports a bird’s location to researchers; it is not a guidance system teaching the bird its migratory route.

Neither of these claims follows from annual arrivals. Tracking observes migration, and a seasonal stopover is evidence of continuing movement between regions rather than permanent residency.

Amur falcons continue their migration toward southern Africa after resting and feeding in Northeast India. Repeated seasonal use of Doyang therefore does not show year-round residence in India.

The Uttarakhand option is not the project identified by Plan Vivo’s certification record. The relevant early community REDD+ programme is in Meghalaya’s Khasi Hills, where carbon finance supports forest conservation and regeneration.

This distractor describes a broader Himalayan collaboration rather than the named Plan Vivo-certified project. The certification and project record identify the Khasi Hills community programme, not an ICFRE–ICIMOD transboundary initiative.

The requested distinction belongs to the Khasi Hills project in Meghalaya. A community or REDD+ label by itself does not establish that a project was the first certified under a specific standard; the certifier’s project record is decisive.

Mangroves can dissipate wave and tidal energy, but that does not make saline mangrove belts freshwater stores ideal for paddy. A true protective function is attached here to an unjustified land-conversion claim.

Both selected statements confuse mangrove adaptations with changing the whole coastal habitat into freshwater farmland or aquaculture. Mangroves live in saline or brackish conditions; protecting them is not equivalent to clearing them for freshwater production.

Statement 3 correctly links protection and livelihoods, but statement 2 describes the roots as salt-sensitive and treats filtration as ecosystem-scale desalination. Salt regulation by a plant does not convert the estuary into a freshwater aquaculture zone.

The 2025 Tiger Reserve designation is correct, but Sakhya Sagar is also a Ramsar wetland inside Madhav National Park. Selecting only the designation overlooks the second independently correct fact.

The Ramsar-site statement is correct, but the cross-state claim is not. A wildlife corridor linking different reserves across a region is different from a single park extending across a state boundary.

The sole selected statement is false: Madhav is located in Madhya Pradesh. Its northern Central Indian landscape and connections toward Rajasthan should not be confused with joint state jurisdiction.

The provisional key treats the BUR figure as empirical support for India’s low-emission direction, but relationship 2 is also selected. The exclusionary short-term claim in statementIII is inconsistent with the broader long-term development approach.

Relationship 2 captures the problem with reducing resilience to short-term target achievement. Relationship 3 does not follow, because a narrow necessary-condition claim about quick reductions does not jointly establish a sound long-term sustainability premise.

Relationship 3 is not the accepted inference. Long-term sustainability involves sustained mitigation, adaptation and development choices; it cannot be established merely by combining a long-term strategy with statementIII’s restrictive claim.

Statement 1 is correct: Hollongapar Gibbon Wildlife Sanctuary in Assam protects the species, whose global category is Endangered. But statement 2 is also correct, so selecting only the sanctuary fact is incomplete.

Brachiation in statement 2 is right, but statement 3 gives the wrong body form. Gibbons’ relatively light bodies and elongated arms suit suspensory canopy travel; a gorilla-like heavy build is not their defining adaptation.

The sole selected statement is the false one. Gibbons and gorillas are both apes, but shared group membership does not mean they have the same body proportions or locomotor specialisation.

The foxtail orchid is an epiphyte: it grows on other plants, commonly tree trunks, for physical support. Statement 1 is therefore true, but selecting it alone misses its recognition as the state flower of both Assam and Arunachal Pradesh.

Statement 3 is correct, but statement 2 confuses regional prominence with endemism. A species is endemic only when naturally restricted to a particular area; this orchid occurs across a much wider Asian range. Statement 1 should be included instead.

Its state-flower status is correctly identified, but statement 1 is also true. Epiphytic growth describes its habitat strategy, while the separate claim that it occurs naturally only in North-east India is false.

More than two pairs are correctly matched. Cassava is indeed a woody shrub, ginger has a pseudostem, and Malabar spinach is a herbaceous climber.

Mint is a perennial herb, not an annual shrub, and papaya has a soft, hollow trunk making it herbaceous rather than a woody shrub. So only three pairs match.

Mint is a creeping perennial herb and papaya is technically a large herbaceous plant, so two of the five pairings are incorrect.

Statement 3 is also correct; the scheme explicitly targets creation of over three lakh skilled personnel through its capacity-building component.

Statement 2 is also correct; the MNRE aims to train personnel at grassroot levels for solar rooftop system installation and maintenance.

Statement 1 is also correct; the scheme targets one crore residential solar rooftop installations across India.

AIIB focuses on infrastructure investment and has not launched this specific nature-finance hub.

NDB (BRICS bank) finances development projects but did not launch this particular initiative.

IBRD (part of the World Bank Group) has its own environmental funds but is not associated with this specific hub.

Statement I is incorrect; the USA produces more ethanol than Brazil, making it the world's largest producer.

Statement I is incorrect; the USA leads global ethanol production, not Brazil.

Statement I is incorrect; the USA surpasses Brazil in ethanol output despite Brazil being the second-largest producer.

The Gooty tarantula is an arachnid (not a crustacean) and is not omnivorous in the conventional sense. It is primarily insectivorous.

Statement 1 is incorrect because a tarantula is an arachnid, not a crustacean. Statement 3 is correct as it lives in tree hollows.

Statement 2 alone is insufficient. Statement 3 is also correct since the Gooty tarantula is arboreal, living in holes of tall trees in its restricted forest habitat.

Both statements are correct and both contribute to explaining GHG reduction — less extraction means less energy use, and less waste means less processing and disposal emissions.

Both Statements II and III are factually correct, not just one.

Both statements are correct; circular economy principles by definition involve reducing virgin material inputs and minimizing waste.

All three items contain plastic polymers, not just one.

All three contain plastic, not just two.

All three items contain various forms of plastic polymers.

Statement 1 is incorrect — India's per capita CO₂ emissions exceed 0.5 tonnes (approximately 1.9 t CO₂/capita).

Statement 3 is also correct — the power sector (electricity and heat) is the single largest source of CO₂ emissions in India.

Statement 1 is wrong; India's per capita CO₂ emissions are approximately 1.9 tonnes, not less than 0.5.

Statement 3 is also correct — captured CO₂ can be combined with green hydrogen to produce synthetic aviation fuels (e-fuels).

Statements 1 and 2 are also correct — DAC can permanently sequester CO₂ underground and supply CO₂ for carbonated beverages and polymer feedstocks.

All three statements are correct descriptions of DAC applications.

Both statements are correct and both contribute to explaining why activated carbon is an attractive remediation tool.

Both Statement II and Statement III are factually correct, not just one.

Both statements are correct. Activated carbon does have a large surface area for adsorption and can be made from agricultural waste and other carbon-rich materials.

Silver nitrate is not the standard cloud-seeding agent; silver iodide is preferred because its crystal structure closely resembles that of ice.

While silver iodide is correct, potassium nitrate is not the standard companion salt used in cloud seeding for pollution control.

Neither silver nitrate nor potassium chloride is the standard agent for cloud seeding to reduce air pollution.

All three fruits were brought to India by the Portuguese, not just one. Papaya, pineapple and guava are all New World species introduced during Portuguese colonial trade.

All three, not just two, were introduced by the Portuguese. There is no basis for excluding any one of them from the list.

All three are well-documented introductions from the New World via Portuguese traders and are not indigenous to the Indian subcontinent.

Statement 1 is not correctly attributed to the specific World Bank report; the report primarily highlighted wet-bulb temperature thresholds.

Statement 1 is not accurately reflecting the report's key finding; the distinctive warning was about lethal heat stress from high wet-bulb temperatures.

Statement 2 is correct — the report specifically warned about wet-bulb temperature thresholds beyond which thermoregulation through sweating fails.

Statement 1 is incorrect because oceans, through phytoplankton, produce roughly half of global oxygen, exceeding rainforest output. Statement 2 is correct.

Statement 1 overstates rainforest contribution relative to oceans, and Statement 3 is factually wrong since atmospheric air contains about 21% oxygen while dissolved oxygen in water is measured in parts per million.

Statement 2 is well-established in marine biology; phytoplankton and photosynthetic bacteria do contribute roughly half of global oxygen production.

The World Bank funds conservation projects but does not enact legislation; NRL is EU legislation.

OECD provides policy recommendations, not binding laws; the NRL is EU-specific legislation.

FAO provides technical guidance on food and agriculture but does not enact environmental restoration laws.

While both statements are correct, only Statement III (calcination of limestone releasing CO₂) directly explains the high carbon emissions. Mixing clay with limestone does not itself release CO₂.

Both statements are factually correct, not just one.

Both statements are correct. Cement manufacturing does use limestone-clay mixtures, and calcination does convert limestone to lime.

All three types use non-conventional powertrains and qualify as alternative vehicles.

Fuel cell electric hybrids also qualify as alternative powertrain vehicles alongside the other two.

All three are recognised alternative powertrain vehicles by transport and energy authorities worldwide.

Hydrogen peroxide is not produced in a PEM fuel cell; the electrochemical reaction yields water, not H₂O₂.

Hydronium (H₃O⁺) is an intermediate ion in aqueous solutions, not a fuel cell exhaust product.

Oxygen is a reactant consumed at the cathode, not an exhaust product of the fuel cell.