UPSC Prelims 2019 Environment questions: topic-wise weightage
UPSC Prelims 2019 asked 21 environment questions in GS Paper I, spread over 5 topics. See the environment weightage for 2019 below, then attempt each question with the official answer and an explanation.
Environment 2019: questions by topic
- Ecology and ecosystems1
- Biodiversity and species4
- Protected areas and conservation4
- Climate change and international conventions2
- Pollution, environmental laws and green technology10
Counted from the 21 questions on this page, tagged by topic in the Battle IAS PYQ bank.
Seeing 21 Environment questions spread over 5 topics can feel overwhelming. That's exactly why the Battle IAS PYQ Book maps every question topic by topic, so you know what to study first. Download free sample
Ecology and ecosystems 1
Consider the following States :
- 1. Chhattisgarh
- 2. Madhya Pradesh
- 3. Maharashtra
- 4. Odisha
With reference to the States mentioned above, in terms of percentage of forest cover to the total area of State, which one of the following is the correct ascending order?
Answer (c) & explanation
The ascending order is Maharashtra, Madhya Pradesh, Odisha, Chhattisgarh (c). By the India State of Forest Report, forest cover as a share of area is about 16–17% in Maharashtra, about 25% in Madhya Pradesh, about 33% in Odisha, and about 41% in Chhattisgarh. The trap is that Madhya Pradesh has the largest forest area in India, but because it is a big state, its share is lower. So options starting with MP (a, b) are wrong, and (d) puts Chhattisgarh before Odisha.
Notice the latest ISFR 2023 (released December 2024): India's forest and tree cover is about 25% of its area. Mizoram has the highest share, while Lakshadweep leads the UTs.
MP tops the list by area, which tempts you to put it last.
Answer as per the official UPSC answer key.
Biodiversity and species 4
Consider the following statements :
- 1. Asiatic lion is naturally found in India only.
- 2. Double-humped camel is naturally found in India only.
- 3. One-horned rhinoceros is naturally found in India only.
Which of the statements given above is/are correct?
Answer (a) & explanation
Only statement 1 is correct (a). Statement 1 is right because the Asiatic lion survives in the wild only in and around Gir in Gujarat. The 2025 census counted 891 lions, spread across the greater Gir landscape. Statement 2 is wrong because the double-humped Bactrian camel lives mainly in Central Asia, Mongolia and China. India has only a small population in Ladakh's Nubra Valley, left from the old silk-route trade. Statement 3 is wrong because the greater one-horned rhino also lives in Nepal, at Chitwan and Bardia, though India's Kaziranga holds about two-thirds of the world's population.
Notice the debate: the Supreme Court ordered lions moved to Kuno, Madhya Pradesh (2013), but cheetahs from Namibia and South Africa went there instead (2022).
Kaziranga makes the rhino feel Indian-only, but Nepal holds several hundred of them.
Answer as per the official UPSC answer key.
Consider the following statements :
- 1. Some species of turtles are herbivores.
- 2. Some species of fish are herbivores.
- 3. Some species of marine mammals are herbivores.
- 4. Some species of snakes are viviparous.
Which of the statements given above are correct?
Answer (d) & explanation
All four statements are correct (d). Statement 1 is right because adult green turtles graze on seagrass and algae. Statement 2 is right because many fish, such as parrotfish, surgeonfish and grass carp, eat plants and algae. Parrotfish help keep reefs clean of algae. Statement 3 is right because dugongs and manatees, the "sea cows", are marine mammals that eat seagrass. Statement 4 is right because many snakes, such as vipers and boas, are viviparous or ovoviviparous, giving birth to live young. Pythons and cobras lay eggs.
Notice the Indian link: dugongs live in the Gulf of Mannar, Palk Bay and the Andamans. Tamil Nadu set up India's first Dugong Conservation Reserve in Palk Bay (2022).
Answer as per the official UPSC answer key.
Consider the following pairs :
| Wildlife | Naturally found in
| 1. Blue-finned Mahseer | Cauvery River
| 2. Irrawaddy Dolphin | Chambal River
| 3. Rusty-spotted Cat | Eastern Ghats
Which of the pairs given above are correctly matched?
Answer (c) & explanation
Pairs 1 and 3 are correct (c). Pair 1 is right because the blue-finned mahseer is found in the Cauvery river system. The hump-backed mahseer, a native Cauvery fish, is now Critically Endangered. Pair 3 is right because the rusty-spotted cat, the world's smallest wild cat, lives in dry forests across India, including the Eastern Ghats. Pair 2 is wrong because the Irrawaddy dolphin lives in coastal lagoons and rivers such as Chilika Lake in Odisha, not in the Chambal. The Chambal has the Ganges river dolphin, India's National Aquatic Animal.
Notice the first river dolphin survey (2025), which counted about 6,300 dolphins, mostly in UP. The Chambal sanctuary is also famous for gharials.
the Chambal does have dolphins, but the Gangetic kind.
Answer as per the official UPSC answer key.
Recently, there was a growing awareness in our country about the importance of Himalayan nettle (*Girardinia diversifolia*) because it is found to be a sustainable source of
Answer (d) & explanation
The Himalayan nettle gives textile fibre (d). Girardinia diversifolia, called allo in Nepal and bichhu buti in Uttarakhand, is a stinging plant that grows wild in the Himalayas. The inner bark of its stem gives long, strong, shiny fibre. Hill communities have long spun it into rope, sacks and cloth. Because it grows wild without fertilisers or irrigation, it is promoted as a sustainable textile, and can be blended with wool or cotton. It is not a known source of antimalarial drugs (a), biodiesel (b) or paper pulp (c).
Notice similar natural fibres being promoted: banana fibre, pineapple leaf fibre, and Eri silk, known as "peace silk" from Assam. The National Technical Textiles Mission backs such innovation.
Answer as per the official UPSC answer key.
Protected areas and conservation 4
Which one of the following National Parks lies completely in the temperate alpine zone?
Answer (d) & explanation
The Valley of Flowers lies fully in the alpine zone (d). This park in Chamoli, Uttarakhand, lies at about 3,200–6,700 m, at or above the tree line. It is a true alpine meadow, famous for blooms such as the blue poppy and brahma kamal. It is part of the Nanda Devi and Valley of Flowers UNESCO World Heritage Site. Manas (a), in Assam, is in the low Terai-Bhabar foothills, with grasslands and tigers. Namdapha (b), Arunachal, and Neora Valley (c), West Bengal, stretch from tropical forest up to high altitudes, covering several zones.
Notice that Namdapha is the only park with four big cats: tiger, leopard, clouded leopard and snow leopard. Neora Valley is a red panda habitat.
Answer as per the official UPSC answer key.
Which of the following are in Agasthyamala Biosphere Reserve?
Answer (a) & explanation
Option (a) lists the parts of Agasthyamala (a). The Agasthyamala Biosphere Reserve, set up in 2001 at the southern tip of the Western Ghats on the Kerala–Tamil Nadu border, includes the Neyyar, Peppara and Shendurney wildlife sanctuaries in Kerala and the Kalakad Mundanthurai Tiger Reserve in Tamil Nadu. It joined UNESCO's World Network of Biosphere Reserves in 2016. It is home to the Kani tribe, known for the Arogyapacha herb. Option (b) describes the Nilgiri Biosphere Reserve, India's first (1986). Options (c) and (d) list protected areas of Andhra Pradesh and Telangana, with Mukurthi wrongly added from the Nilgiris.
India has 18 biosphere reserves, of which 13 are in the UNESCO network. Notice that Cold Desert (Himachal) joined in 2025.
(b) is a real biosphere reserve set, so it looks right; it is the Nilgiri one.
Answer as per the official UPSC answer key.
Consider the following statements :
- 1. Under Ramsar Convention, it is mandatory on the part of the Government of India to protect and conserve all the wetlands in the territory of India.
- 2. The Wetlands (Conservation and Management) Rules, 2010 were framed by the Government of India based on the recommendations of Ramsar Convention.
- 3. The Wetlands (Conservation and Management) Rules, 2010 also encompass the drainage area or catchment regions of the wetlands as determined by the authority.
Which of the statements given above is/are correct?
Answer (c) & explanation
Only statement 3 is correct (c). Statement 1 is wrong because the Ramsar Convention (1971, in Iran) asks members to ensure the "wise use" of all wetlands and protect listed Ramsar sites. It does not make it mandatory to protect every wetland. Statement 2 is wrong because the 2010 Rules were framed under the Environment (Protection) Act, 1986, not on Ramsar's recommendation. Statement 3 is right because the 2010 Rules covered a wetland's catchment or drainage area, as fixed by the authority.
The 2010 Rules were replaced by the Wetlands Rules, 2017, which gave states more power through State Wetland Authorities. Notice India's tally: over 90 Ramsar sites, with Tamil Nadu having the most, and the Amrit Dharohar scheme.
"mandatory" and "all" in statement 1 are too strong for a convention.
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Answer as per the official UPSC answer key.
Consider the following statements :
- 1. As per law, the Compensatory Afforestation Fund Management and Planning Authority exists at both National and State levels.
- 2. People’s participation is mandatory in the compensatory afforestation programmes carried out under the Compensatory Afforestation Fund Act, 2016.
Which of the statements given above is/are correct?
Answer (a) & explanation
Only statement 1 is correct (a). When forest land is given to a project, such as a mine or a road, the project pays for compensatory afforestation to replace the lost forest. The Compensatory Afforestation Fund Act, 2016 created a National CAMPA and State CAMPAs to manage this money (1). Statement 2 is wrong because the Act does not make people's participation compulsory. Critics point out that it ignores gram sabhas and forest rights under the FRA.
The fund holds well over ₹90,000 crore. Notice the concerns: afforestation on poor or non-forest land, and money used for other purposes. The Forest (Conservation) Amendment Act, 2023, renamed the Van (Sanrakshan Evam Samvardhan) Adhiniyam, also changed which land counts as forest.
Answer as per the official UPSC answer key.
Climate change and international conventions 2
In the context of which of the following do some scientists suggest the use of cirrus cloud thinning technique and the injection of sulphate aerosol into stratosphere?
Answer (d) & explanation
Both techniques aim to reduce global warming (d). They are geoengineering, or solar radiation management, ideas. Sulphate aerosols sprayed into the stratosphere would reflect sunlight back to space, copying big volcanic eruptions such as Mount Pinatubo (1991), which cooled the Earth by about 0.5°C. Cirrus cloud thinning would let more heat escape to space, because thin, high cirrus clouds trap outgoing heat. They are not for artificial rain (a), which uses cloud seeding with silver iodide; nor for cyclones (b); nor for solar wind (c).
Notice the risks: changed monsoons, ozone damage, and termination shock if it stops suddenly. Delhi tried cloud seeding against smog in 2025.
Answer as per the official UPSC answer key.
Which of the following statements are correct about the deposits of ‘methane hydrate’?
- 1. Global warming might trigger the release of methane gas from these deposits.
- 2. Large deposits of ‘methane hydrate’ are found in Arctic Tundra and under the seafloor.
- 3. Methane in atmosphere oxidizes to carbon dioxide after a decade or two.
Which of the statements given above are correct?
Answer (d) & explanation
All three statements are correct (d). Methane hydrate, or "fire ice", is methane trapped in ice-like crystals. It is stable only under cold and high pressure. Statement 2 is right because big deposits lie in Arctic permafrost and in seafloor sediments along continental margins. Statement 1 is right because warming could melt them and release methane, a strong greenhouse gas. This could set off a feedback loop, the "clathrate gun" idea. Statement 3 is right because methane in air lasts about a decade before it oxidises into CO₂ and water.
Methane is over 80 times stronger than CO₂ over 20 years. Notice India's interest: the National Gas Hydrate Programme found deposits in the Krishna–Godavari basin.
Answer as per the official UPSC answer key.
Pollution, environmental laws and green technology 10
In the context of which one of the following are the terms ‘pyrolysis and plasma gasification’ mentioned?
Answer (d) & explanation
These are waste-to-energy technologies (d). Pyrolysis heats waste, such as plastics or biomass, to high temperatures without oxygen. Instead of burning, the material breaks down into pyrolysis oil, gas (syngas) and char. Plasma gasification uses a plasma torch, at several thousand degrees, to break waste down into syngas (mainly hydrogen and carbon monoxide), leaving a glassy, harmless slag. Both turn waste into fuel or power and reduce the load on landfills. They are not used for extracting rare earths (a) or natural gas (b), and they are not hydrogen car technology (c), though syngas can yield hydrogen.
Notice India's rules: the Solid Waste Management Rules, 2016 (being updated) promote waste-to-energy, and the SATAT scheme backs compressed biogas from waste.
Answer as per the official UPSC answer key.
Why is there a great concern about the ‘microbeads’ that are released into environment?
Answer (a) & explanation
Microbeads harm marine ecosystems (a). Microbeads are tiny plastic balls, under 5 mm and often under 1 mm, that were added to face scrubs, toothpaste and cosmetics. They are too small to be caught by sewage plants, so they flow into rivers and seas. Fish, plankton and shellfish swallow them, and they soak up toxic chemicals, which move up the food chain to humans. They are not known to cause skin cancer (b), are not absorbed by crop plants (c), and are not food adulterants (d).
Notice the rules: the USA banned them in 2015, and India's BIS declared them unsafe for cosmetics (2017). India banned single-use plastic items from July 2022, and global talks on a plastics treaty continue.
Answer as per the official UPSC answer key.
Consider the following :
- 1. Carbon monoxide
- 2. Methane
- 3. Ozone
- 4. Sulphur dioxide
Which of the above are released into atmosphere due to the burning of crop/biomass residue?
Answer (d) & explanation
All four are released (d). Burning crop residue, such as stubble in Punjab and Haryana, gives off carbon monoxide (1) from incomplete burning, methane (2), and sulphur dioxide (4), along with soot and fine particles (PM2.5). It also releases nitrogen oxides and volatile organic compounds. These react in sunlight to form ground-level ozone (3), a secondary pollutant. UPSC's key counts ozone as released, so all four are correct.
Notice the fixes: the Happy Seeder and in-situ machines, Pusa decomposer, using stubble in power plants and 2G ethanol, and penalties set by the CAQM. Stubble fires fell sharply by 2024–25, though satellites suggest some burning has shifted to evening hours.
ozone is not given off directly; it forms from the smoke. UPSC still counts it.
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Answer as per the official UPSC answer key.
In India, the use of carbofuran, methyl parathion, phorate and triazophos is viewed with apprehension. These chemicals are used as
Answer (a) & explanation
These chemicals are agricultural pesticides (a). Carbofuran, methyl parathion, phorate and triazophos are highly toxic insecticides. Most are organophosphates and carbamates, which harm the nervous system of insects and, in large doses, of humans and animals. Carbofuran is notorious for poisoning birds, such as sarus cranes and vultures, and for being misused in fish and wildlife poisoning. They are not food preservatives (b), fruit-ripening agents (c) such as calcium carbide or ethylene, or cosmetic moisturisers (d).
Notice India's moves: the government banned 18 pesticides after the Anupam Verma Committee and later restricted more, and the Pesticide Management Bill is pending. The Yavatmal poisonings (2017) of farmers spraying cotton made the risk clear.
Answer as per the official UPSC answer key.
Consider the following statements :
- 1. Agricultural soils release nitrogen oxides into environment.
- 2. Cattle release ammonia into environment.
- 3. Poultry industry releases reactive nitrogen compounds into environment.
Which of the statements given above is/are correct?
Answer (d) & explanation
All three statements are correct (d). These are all sources of reactive nitrogen, meaning nitrogen in forms other than inert N₂ gas. Statement 1 is right because fertilised farm soils give off nitrous oxide (N₂O), a powerful greenhouse gas, and nitric oxide, as microbes act on extra urea. Statement 2 is right because cattle dung and urine release ammonia. Statement 3 is right because poultry farms release ammonia and other nitrogen compounds from droppings. The Indian Nitrogen Assessment (2017) named all three, with cereals and livestock as the main sources.
Notice the solutions: neem-coated urea (mandatory since 2015), nano urea by IFFCO, and soil health cards. India's 2019 UNEA resolution on sustainable nitrogen management was adopted.
Answer as per the official UPSC answer key.
In the context of proposals to the use of hydrogen-enriched CNG (H-CNG) as fuel for buses in public transport, consider the following statements :
- 1. The main advantage of the use of H-CNG is the elimination of carbon monoxide emissions.
- 2. H-CNG as fuel reduces carbon dioxide and hydrocarbon emissions.
- 3. Hydrogen up to one-fifth by volume can be blended with CNG as fuel for buses.
- 4. H-CNG makes the fuel less expensive than CNG.
Which of the statements given above is/are correct?
Answer (b) & explanation
Statements 2 and 3 are correct (b). H-CNG blends hydrogen into compressed natural gas. Statement 3 is right because about 18–20% hydrogen by volume, roughly one-fifth, can be used in bus engines with small changes. Statement 2 is right because burning less carbon lowers CO₂ and hydrocarbon emissions. Statement 1 is wrong because it reduces carbon monoxide, by up to about 70%, but does not eliminate it. Statement 4 is wrong because hydrogen costs more than natural gas, so H-CNG is dearer than plain CNG.
Delhi ran trials on H-CNG buses from 2020. Notice the National Green Hydrogen Mission (2023), which aims at 5 million tonnes of green hydrogen a year by 2030, with hydrogen buses in Leh and Delhi.
"elimination" is too strong; H-CNG reduces CO, not removes it.
Answer as per the official UPSC answer key.
Consider the following statements :
- 1. As per recent amendment to the Indian Forest Act, 1927, forest dwellers have the right to fell the bamboos grown on forest areas.
- 2. As per the Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006, bamboo is a minor forest produce.
- 3. The Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006 allows ownership of minor forest produce to forest dwellers.
Which of the statements given above is/are correct?
Answer (b) & explanation
Statements 2 and 3 are correct (b). Statement 1 is wrong because the 2017 amendment to the Indian Forest Act, 1927 removed bamboo grown outside forests from the definition of "tree". So it can be cut and moved without permits, helping farmers earn from it. It did not give forest dwellers a right to fell bamboo inside forests. Statement 2 is right because the Forest Rights Act, 2006 lists bamboo as minor forest produce, along with tendu leaves, honey and lac. Statement 3 is right because the Act gives forest dwellers the right of ownership, access to collect, use and sell minor forest produce.
Notice the success story: Mendha Lekha village in Gadchiroli, Maharashtra, became the first to earn from bamboo under community rights. The National Bamboo Mission was restructured in 2018.
the 2017 change was about bamboo outside forests. The question says "forest areas".
Answer as per the official UPSC answer key.
Consider the following statements :
The Environment Protection Act, 1986 empowers the Government of India to
- 1. state the requirement of public participation in the process of environmental protection, and the procedure and manner in which it is sought
- 2. lay down the standards for emission or discharge of environmental pollutants from various sources
Which of the statements given above is/are correct?
Answer (b) & explanation
Only statement 2 is correct (b). The Environment (Protection) Act, 1986, passed after the Bhopal gas tragedy, is an "umbrella" law. Section 3 gives the Centre wide powers, including setting standards for emissions and discharges of pollutants from various sources (2), restricting industries in certain areas, and handling hazardous substances. Statement 1 is wrong because the Act itself says nothing about public participation. Public hearings come from the EIA Notification (1994, 2006) issued under the Act.
The Act also lets the Centre set up authorities, such as the CAQM for Delhi's air. Notice the 2023 Jan Vishwas changes, which replaced jail terms for many EPA violations with penalties. The draft EIA 2020 was criticised for weakening public hearings.
Answer as per the official UPSC answer key.
As per the Solid Waste Management Rules, 2016 in India, which one of the following statements is correct?
Answer (c) & explanation
Option (c) is correct. The Solid Waste Management Rules, 2016 give detailed criteria for choosing sites for landfills and waste processing plants, such as distance from rivers, homes and airports. Option (a) is wrong because generators must sort waste into three streams: wet (biodegradable), dry and domestic hazardous. Option (b) is wrong because the Rules apply beyond urban local bodies, to census towns, special economic zones, railways, airports, ports, defence areas and places of pilgrimage. Option (d) is wrong because there is no ban on moving waste between districts.
The Rules made bulk generators responsible for processing their waste and introduced user fees. Notice the SWM Rules, 2026 (in force from April 2026), which replaced them and require four-stream segregation: wet, dry, sanitary and special-care waste.
Answer as per the official UPSC answer key.
In India, ‘extended producer responsibility’ was introduced as an important feature in which of the following?
Answer (c) & explanation
EPR was introduced as a key feature in the e-Waste Rules, 2011 (c). Extended Producer Responsibility makes a manufacturer responsible for its products even after use, by collecting and recycling them at the end of their life. India first made it a central feature in the e-Waste (Management and Handling) Rules, 2011, which came into force in 2012. The Bio-medical Waste Rules, 1998 (a) and the Recycled Plastic Rules, 1999 (b) did not centre on EPR. The Food Safety Regulations, 2011 (d) deal with food standards.
Later, EPR spread to plastic packaging (Plastic Waste Management Rules, 2016, with EPR guidelines in 2022), batteries (2022), tyres (2022) and used oil. Notice the E-Waste Rules, 2022, which set yearly recycling targets and an online EPR portal.
Answer as per the official UPSC answer key.
All years by topic
Every question from 2011 to 2026, grouped by syllabus topic, with year-wise trends.