Environment & Ecology Previous Year Questions (PYQ) with Answers – Page 3

The correct answer is A, Carbon captured by oceans and coastal ecosystems. Blue carbon is the carbon stored by marine and coastal ecosystems, especially mangroves, salt marshes and seagrass meadows. These plants take in carbon dioxide, and because their waterlogged soils have little oxygen, dead matter decays slowly and the carbon stays locked in the sediment for hundreds or even thousands of years. Area for area, they can store several times more carbon than tropical forests, which is why protecting the Sundarbans and India's seagrass beds counts as climate action. When these habitats are cleared, the stored carbon goes back into the air. Option B is wrong because carbon held in forest biomass and farm soils is called green carbon. Option C is wrong because carbon in petroleum and natural gas is fossil carbon, which is released as carbon dioxide when burnt. Option D is wrong because carbon dioxide in the air is simply atmospheric carbon, not stored carbon. Exam tip: blue carbon means coasts and oceans, green carbon means forests and soils.

The correct answer is D, 29th July. International Tiger Day, also called Global Tiger Day, is observed every year on 29 July. It was started in 2010 at the Tiger Summit held in St Petersburg, Russia, where the thirteen tiger-range countries promised to double the number of wild tigers by 2022. The day spreads awareness about the loss of tiger habitat and poaching. India is home to about three-fourths of the world's wild tigers; it launched Project Tiger on 1 April 1973 from Jim Corbett National Park, and the National Tiger Conservation Authority was set up in 2005. The tiger is India's national animal and the results of the tiger census are usually released around this day. A is wrong because 12 May is International Nurses Day, the birthday of Florence Nightingale. B is wrong because 10 January is World Hindi Day. C is wrong because 5 November is World Tsunami Awareness Day. Exam tip: 29 July Tiger Day (St Petersburg 2010); Project Tiger 1973; 12 August is World Elephant Day.

The correct answer is C, Secondary consumers. In a food chain each step at which energy is transferred is a trophic level, and secondary consumers stand at the third step. The first trophic level is the producers, green plants that make food by photosynthesis; the second is the primary consumers, herbivores that eat plants; the third is the secondary consumers, carnivores that eat the herbivores; and the fourth is the tertiary or top consumers. In the chain grass, grasshopper, frog, snake, eagle, the frog is at the third level. Only about 10 percent of energy passes from one level to the next (Lindeman's ten percent law), so chains rarely go beyond four or five levels. A is wrong because primary consumers are the herbivores of the second level. B is wrong because top consumers sit at the fourth or final level. D is wrong because producers form the first level, the base of every chain. Exam tip: producers 1, herbivores 2, carnivores 3, top carnivores 4.

The correct answer is B, Namdapha National Park. Namdapha lies in Changlang district of Arunachal Pradesh, covers about 1,985 square kilometres and is the largest protected area in the Eastern Himalayan sub-region. It was declared a national park in 1983 and is also a tiger reserve. Its land climbs from about 200 metres on the Noa-Dihing river to more than 4,500 metres, so tropical rainforest, temperate forest and alpine meadow all lie inside one park; it is the only protected area known to hold four large cats — tiger, leopard, snow leopard and clouded leopard. Option A is wrong because Jim Corbett, in Uttarakhand, belongs to the Western Himalayan foothills. Option C is wrong because Keibul Lamjao in Manipur is the world's only floating national park and is very small. Option D is wrong because Bandipur is in Karnataka, in the Western Ghats, far from the Himalayas. Exam tip: Namdapha — Arunachal Pradesh, four big cats, the Noa-Dihing river and the hoolock gibbon.

The correct answer is C, 1986. Parliament passed the Environment (Protection) Act in 1986 and it came into force on 19 November 1986. It was enacted soon after the Bhopal gas tragedy of December 1984, when the country needed one general law to fill the gaps left by the earlier pollution laws. Parliament used Article 253, which allows it to legislate to carry out international agreements, so the Act gives effect to the decisions of the 1972 Stockholm Conference on the Human Environment. It is called an umbrella law because it gives the Central Government wide powers to fix standards, inspect and shut polluting units and frame rules, and most later environmental rules are made under it. A is wrong because no such central environment Act was passed in 1990. B is wrong because 1991 is the year of the Public Liability Insurance Act. D is wrong because 1988 only brought amendments to the Water Act. Exam tip: Water Act 1974, Air Act 1981, Environment (Protection) Act 1986.

The correct answer is C, Rachel Carson. Rachel Carson, an American marine biologist and writer, published Silent Spring in 1962. She showed how synthetic pesticides, above all DDT, were killing birds, fish and insects far beyond the fields where they were sprayed, and how these chemicals build up in food chains, becoming more concentrated at each level, a process now called biomagnification. The title imagines a spring with no birdsong because the birds have been poisoned. The book stirred public opinion and helped lead to the creation of the US Environmental Protection Agency in 1970 and a ban on most uses of DDT in the USA in 1972. Option A is wrong because Carolyn Merchant is an environmental historian known for The Death of Nature (1980). Option B is wrong because Karl Marx wrote Das Kapital and the Communist Manifesto, works on economics and politics. Option D is wrong because no writer of that name is linked to this book. Exam tip: Silent Spring 1962 (Rachel Carson, DDT), The Limits to Growth 1972 (Club of Rome), Our Common Future 1987 (Brundtland Report).

The correct answer is D, air pollution. Lichens are used as bio-indicators of air quality because they are extremely sensitive to sulphur dioxide and other gases in the air. A lichen is a partnership of a fungus and an alga (or cyanobacterium) living together; it has no roots and takes water and minerals straight from the air, so pollutants build up in it quickly. That is why lichens grow well on trees and rocks in clean hill areas but disappear from the centres of polluted cities, and scientists map their presence to judge how clean the air is. A is wrong because gas pollution is not a separate category; the gases concerned are part of air pollution. B is wrong because water pollution is judged with indicators such as coliform bacteria, BOD and algal blooms. C is wrong because soil pollution is tracked through earthworms and soil tests, not lichens. Exam tip: lichen equals sulphur dioxide equals air pollution indicator.

The correct answer is A, Madhya Pradesh. Kanha Tiger Reserve lies in the Mandla and Balaghat districts of Madhya Pradesh, in the Maikal hills at the eastern end of the Satpura range. It was among the first nine tiger reserves created when Project Tiger was launched in 1973. Kanha is best known for saving the hard-ground barasingha, a swamp deer that had almost died out and is now the state animal of Madhya Pradesh. Its open sal forests and grassy meadows make it one of the best places in India to see tigers in the wild. Madhya Pradesh's other well-known tiger reserves include Bandhavgarh, Panna, Pench and Satpura. B is wrong because Karnataka's famous tiger reserves are Bandipur and Nagarhole. C is wrong because Odisha's main tiger reserve is Similipal. D is wrong because Maharashtra's best-known tiger reserves are Tadoba-Andhari and Melghat. Exam tip: Kanha = Madhya Pradesh = barasingha; one of the first nine Project Tiger reserves of 1973.

The correct answer is C, Polythene bag. Polythene is a synthetic plastic that bacteria and fungi cannot break down, so it is non-biodegradable. A plastic bag can stay in soil or water for hundreds of years. Biodegradable waste is anything that decomposers can break down into simple, harmless substances, and it usually comes from plants or animals. Plastic bags choke drains and cause waterlogging, are swallowed by cattle and sea animals, and give off toxic gases when burnt, which is why their use must be reduced and the bags reused and recycled rather than thrown away. Waste is best kept in two bins: wet (biodegradable) and dry (non-biodegradable). A is wrong because vegetable peels rot within days and make good compost. B is wrong because dead leaves decay into humus that enriches the soil. D is wrong because a rotting fruit is already being broken down by microbes. Exam tip: if microbes can eat it, it is biodegradable; plastic, glass, metal cans and DDT are not.

The correct answer is D, Forest Act 1878. The Indian Forest Act of 1878 created the three classes of reserved, protected and village forests. British interest in Indian forests grew as the railways and shipbuilding needed huge amounts of timber. The Imperial Forest Department was set up in 1864 with Dietrich Brandis as the first Inspector General of Forests, and the first Indian Forest Act followed in 1865. That Act was soon found too weak, so the 1878 Act replaced it, giving the state firm control over forest land and sharply cutting down villagers' customary rights, above all in reserved forests. Its successor, the Indian Forest Act, 1927, kept the same three classes and is still the main forest law. Option A is wrong because 1864 is the year the Forest Department was created, not a classification law. Option B is wrong because the 1865 Act only began state control and did not create the three classes. Option C is wrong because 1866 is not linked with this classification at all. Exam tip: 1864 department, 1865 first Act, 1878 three classes, 1927 Act still in use.

The correct answer is C, Protection of ozone layer. Both treaties were made to save the ozone layer in the stratosphere, which screens out harmful ultraviolet rays. The Vienna Convention for the Protection of the Ozone Layer was adopted in 1985 as a framework agreement. The Montreal Protocol of 1987 put it into action by fixing deadlines to phase out ozone-depleting substances such as chlorofluorocarbons (CFCs) and halons. In 2009 these became the first UN treaties ratified by every country, and 16 September, the day the Protocol was signed, is observed as World Ozone Day. The Kigali Amendment of 2016 extended the Protocol to hydrofluorocarbons (HFCs). Option A is wrong because desertification is handled by the UN Convention to Combat Desertification of 1994. Option B is wrong because the Sustainable Development Goals were adopted by the UN General Assembly in 2015 as part of Agenda 2030. Option D is wrong because climate change falls under the UNFCCC of 1992, with its Kyoto Protocol and Paris Agreement. Exam tip: Vienna 1985 and Montreal 1987 for ozone; Kigali 2016 added HFCs.

The correct answer is A, Lichens. A bioindicator is a living organism whose presence, absence or health tells us about the quality of the environment. Lichens are a partnership between a fungus and an alga or cyanobacterium; they have no roots and take water and nutrients straight from the air and rain. This makes them very sensitive to air pollution, especially sulphur dioxide. They vanish from the bark of trees in polluted cities and grow richly where the air is clean, so scientists map lichens to judge air quality. Mosses are used in a similar way. Option B is wrong because methyl mercury is a toxic pollutant, not a living indicator; it caused Minamata disease in Japan in the 1950s. Option C is wrong because the rose plant is not used as a standard indicator of air quality. Option D is wrong because the sunflower is not a recognised air pollution indicator either. Exam tip: lichens indicate sulphur dioxide in the air; E. coli in water indicates faecal pollution.

The correct answer is B, greenhouse gases emission. The Kyoto Protocol, adopted at Kyoto, Japan on 11 December 1997 under the UN Framework Convention on Climate Change, was the first treaty to set binding targets for cutting emissions. It came into force on 16 February 2005 and asked industrialised countries to cut their greenhouse gas emissions by an average of about 5 per cent below 1990 levels during 2008 to 2012. It covered six gases, including carbon dioxide, methane and nitrous oxide, and created market tools such as the Clean Development Mechanism, which let projects in countries like India earn carbon credits. India ratified it in 2002 but, as a developing country, had no binding target. A is wrong, because cutting poverty is the aim of goals such as the UN Sustainable Development Goals, not Kyoto. C is wrong, because nuclear arms are dealt with by treaties like the Non-Proliferation Treaty of 1968. D is wrong, because farm subsidies fall under the WTO's Agreement on Agriculture. Exam tip: Kyoto 1997, in force 2005, binding cuts for rich nations; Paris 2015, pledges from all nations.

The correct answer is D, Blue Flag. In 2018 the Union Environment Ministry started a pilot project to clean up and develop selected beaches so that they could win the Blue Flag. The Blue Flag is an international eco-label given by the Foundation for Environmental Education (FEE), based in Copenhagen, Denmark; it began in France in 1985. A beach must meet strict standards on water quality, environmental education, safety and services, and environmental management. India's programme for this is called BEAMS (Beach Environment and Aesthetics Management Services), and in 2020 Shivrajpur in Gujarat was among the first Indian beaches to receive the Blue Flag. A is wrong because Swachh Bharat is the national sanitation mission started in 2014, not a beach label. B is wrong because the Green Flag is a different award, used in the UK for well-kept parks and green spaces. C is wrong because Clean India is only the English name of the Swachh Bharat campaign. Exam tip: Blue Flag = beach eco-label by FEE, Denmark; India's scheme = BEAMS; the first eight Indian Blue Flag beaches were certified in 2020.