Environment and Ecology has become one of the most regular parts of the general knowledge paper. The NDA General Ability Test, the CDS General Knowledge paper, AFCAT general awareness, the UPSC Civil Services preliminary exam, SSC and state PSC exams all ask questions on ecosystems, food chains, national parks, endangered species, pollution, climate change and the treaties that protect the environment.
This article brings together 100 of the most important Environment and Ecology GK questions on these high-frequency themes. The set is divided into four parts: Ecology and Ecosystems (questions 1 to 25), Biodiversity and Wildlife Conservation in India (26 to 50), Pollution and Climate Change (51 to 75), and Environmental Laws, Conventions and Institutions (76 to 100). It follows our Indian History, Indian Geography, Indian Polity, Indian Economy and General Science sets, so you can revise all six subjects in the same way.
The questions are based on NCERT books, especially the ecology and environment chapters of Class 12 Biology and the Class 8 and Class 10 science books, along with standard facts about Indian laws and international agreements. Read each question, try to recall the answer, and only then read the short explanation, which adds the related fact that examiners often turn into a second question.
Ecology and Ecosystems (Questions 1 to 25)
1. Who coined the term “ecology”?
Answer: Ernst Haeckel. The German biologist Ernst Haeckel coined the term in 1866. Ecology is the study of the relationships of living organisms with each other and with their physical environment.
2. Who coined the term “ecosystem”?
Answer: Arthur George Tansley. The British ecologist A.G. Tansley used the term in 1935. An ecosystem is a functional unit of nature in which living organisms interact among themselves and with the non-living environment.
3. Which organisms are called producers in an ecosystem?
Answer: Green plants and other organisms that make their own food by photosynthesis. Producers are autotrophs and form the first trophic level. Herbivores are primary consumers, and animals that eat herbivores are secondary consumers.
4. Which organisms break down dead plants and animals and return nutrients to the soil?
Answer: Decomposers, mainly bacteria and fungi. Decomposers convert complex organic matter into simple inorganic substances. Without them, nutrients would stay locked in dead bodies and the cycling of matter would stop.
5. According to the ten per cent law, how much energy passes from one trophic level to the next?
Answer: About 10 per cent. The ten per cent law was given by Raymond Lindeman in 1942. Because most energy is lost as heat at each step, food chains usually have only three or four trophic levels.
6. Which ecological pyramid is always upright?
Answer: The pyramid of energy. Energy decreases at every higher trophic level, so the pyramid of energy can never be inverted. Pyramids of numbers and biomass can be inverted in some ecosystems.
7. In which type of ecosystem is the pyramid of biomass usually inverted?
Answer: An aquatic ecosystem such as a pond or the sea. At any given time the biomass of phytoplankton is smaller than that of the zooplankton and fish feeding on them, because phytoplankton multiply very quickly.
8. Which ecosystem gives an inverted pyramid of numbers?
Answer: A tree (single large tree) ecosystem. One large tree supports a great number of insects and birds that feed on it, so the producer level has fewer individuals than the consumer level.
9. What is biomagnification?
Answer: The increase in concentration of a toxic, non-biodegradable substance at successive trophic levels. Substances such as DDT and mercury are not broken down or excreted easily, so they build up in top predators. DDT made the eggshells of fish-eating birds thin and fragile.
10. What is an ecotone?
Answer: A transition zone between two different ecosystems or communities. Examples are the zone between a forest and a grassland, or an estuary between a river and the sea. Ecotones often have more species than either neighbouring community, which is called the edge effect.
11. What is meant by the ecological niche of a species?
Answer: The functional role of a species in its habitat, including what it eats and how it uses resources. Habitat is the address of an organism, while niche is its profession. Two species cannot occupy exactly the same niche for long in the same place.
12. Which organisms are the pioneer species on bare rocks in ecological succession?
Answer: Lichens. Lichens secrete acids that slowly break down rock and help form soil. They are followed by mosses, herbs, shrubs and finally trees.
13. What is the stable, final community at the end of ecological succession called?
Answer: The climax community. A climax community remains in balance with the climate of the area. Succession that begins on bare rock or in water where no life existed is called primary succession.
14. Which is the largest ecosystem on the Earth?
Answer: The ocean (marine ecosystem). Oceans cover about 71 per cent of the Earth’s surface. Marine phytoplankton produce a large share of the oxygen in the atmosphere.
15. Which terrestrial biome has the highest biodiversity?
Answer: Tropical rainforests. Tropical rainforests receive high rainfall and high temperatures throughout the year. The Amazon basin holds the largest tropical rainforest in the world.
16. What is the mutually beneficial association between fungi and the roots of higher plants called?
Answer: Mycorrhiza. The fungus helps the plant absorb water and minerals, especially phosphorus, and the plant supplies the fungus with food. Pines commonly depend on mycorrhizal fungi.
17. A lichen is a symbiotic association between which two organisms?
Answer: An alga and a fungus. The alga makes food by photosynthesis and the fungus provides shelter, water and minerals. Lichens are sensitive to sulphur dioxide, so they are used as indicators of air pollution.
18. What is an interaction called in which one species benefits and the other is neither harmed nor benefited?
Answer: Commensalism. An orchid growing on a mango branch and a barnacle on a whale are standard examples. In mutualism both species benefit, and in parasitism one benefits at the cost of the other.
19. Which bacterium fixes atmospheric nitrogen in the root nodules of leguminous plants?
Answer: Rhizobium. Pulses such as gram, pea and moong host Rhizobium in root nodules, which is why legumes improve soil fertility. Free-living bacteria such as Azotobacter and cyanobacteria such as Anabaena also fix nitrogen.
20. What is the conversion of ammonia into nitrites and nitrates by soil bacteria called?
Answer: Nitrification. Nitrosomonas converts ammonia to nitrite and Nitrobacter converts nitrite to nitrate. Denitrification, carried out by bacteria such as Pseudomonas, returns nitrogen gas to the atmosphere.
21. What is eutrophication?
Answer: The enrichment of a water body with nutrients, leading to excessive growth of algae. Run-off of fertilisers rich in nitrates and phosphates and untreated sewage cause algal blooms. When the algae die and decompose, dissolved oxygen falls and fish die.
22. What does BOD (Biochemical Oxygen Demand) of water indicate?
Answer: The amount of organic pollution in water. BOD is the oxygen needed by microorganisms to decompose organic matter in water. The higher the BOD, the more polluted the water.
23. What are mangroves?
Answer: Salt-tolerant trees and shrubs that grow in coastal intertidal zones. Mangroves have breathing roots called pneumatophores and protect coasts from storms and tsunamis. The Sundarbans in West Bengal and Bangladesh form the largest mangrove forest in the world.
24. Which organisms are the main producers of the open ocean?
Answer: Phytoplankton. Phytoplankton are microscopic floating algae and cyanobacteria. They form the base of almost every marine food chain.
25. What is a keystone species?
Answer: A species whose effect on its ecosystem is much larger than its numbers suggest. Removing a keystone species changes the whole community. Top predators such as the tiger are often described as keystone species, while a flagship species is one chosen to attract public support for conservation.
Biodiversity and Wildlife Conservation in India (Questions 26 to 50)
26. Who gave the concept of biodiversity hotspots?
Answer: Norman Myers. The British ecologist Norman Myers proposed the idea in 1988. A hotspot must have at least 1,500 endemic plant species and must have lost at least 70 per cent of its original habitat.
27. How many of the world’s biodiversity hotspots are found wholly or partly in India?
Answer: Four. They are the Himalaya, Indo-Burma, the Western Ghats and Sri Lanka, and Sundaland, which includes the Nicobar Islands. The world has 36 recognised hotspots.
28. Why is India called a megadiverse country?
Answer: Because it holds a very large share of the world’s species on a small share of its land. India has about 2.4 per cent of the world’s land area but about 7 to 8 per cent of its recorded species. It is one of the 17 megadiverse countries.
29. Which of these is ex situ conservation: a national park, a biosphere reserve or a seed bank?
Answer: A seed bank. Ex situ conservation protects species outside their natural habitat, as in zoos, botanical gardens, seed banks and gene banks. National parks, sanctuaries and biosphere reserves are in situ conservation.
30. Which was the first national park of India?
Answer: Jim Corbett National Park, Uttarakhand. It was set up in 1936 as Hailey National Park and later renamed after the hunter-naturalist Jim Corbett. Project Tiger was launched here in 1973.
31. In which year was Project Tiger launched?
Answer: 1973. Project Tiger began on 1 April 1973 with nine tiger reserves. The National Tiger Conservation Authority (NTCA) was set up in 2006 through an amendment to the Wildlife (Protection) Act.
32. In which year was Project Elephant launched?
Answer: 1992. Project Elephant protects elephants, their habitats and corridors and tries to reduce human-elephant conflict. The elephant was declared the National Heritage Animal of India in 2010.
33. Which state had the highest number of tigers in the All India Tiger Estimation 2022?
Answer: Madhya Pradesh. Madhya Pradesh had 785 tigers, followed by Karnataka and Uttarakhand. India’s estimated tiger population in 2022 was about 3,682, the largest in the world.
34. Where is the only wild home of the Asiatic lion?
Answer: Gir National Park and the surrounding Gir forests of Gujarat. The Asiatic lion survives in the wild only in the Saurashtra region of Gujarat. It is listed as Endangered by the IUCN.
35. Which national park is famous for the Indian one-horned rhinoceros?
Answer: Kaziranga National Park, Assam. Kaziranga holds the largest population of the one-horned rhinoceros in the world and was declared a UNESCO World Heritage Site in 1985. Pobitora, Orang and Jaldapara also have rhinos.
36. Which is the only floating national park in the world?
Answer: Keibul Lamjao National Park, Manipur. It lies on Loktak Lake and is made of floating masses of vegetation called phumdis. It is the last natural home of the sangai, the brow-antlered deer.
37. Which was the first biosphere reserve of India?
Answer: The Nilgiri Biosphere Reserve. It was set up in 1986 and spreads across Tamil Nadu, Kerala and Karnataka. Biosphere reserves have a core zone, a buffer zone and an outer transition zone.
38. Which is the largest biosphere reserve in India by area?
Answer: The Great Rann of Kachchh Biosphere Reserve, Gujarat. It covers more than 12,000 square kilometres. The Gulf of Mannar Biosphere Reserve in Tamil Nadu was the first marine biosphere reserve in South and Southeast Asia.
39. Which is the National Aquatic Animal of India?
Answer: The Ganges river dolphin. It was declared the National Aquatic Animal in 2009. It is nearly blind and finds its way and its food by echolocation. Vikramshila Gangetic Dolphin Sanctuary is in Bihar.
40. Which organisation publishes the Red List of Threatened Species?
Answer: The International Union for Conservation of Nature (IUCN). The IUCN was founded in 1948 and has its headquarters at Gland, Switzerland. The Red List categories include Critically Endangered, Endangered and Vulnerable.
41. Which critically endangered bird is the state bird of Rajasthan?
Answer: The Great Indian Bustard. Collisions with power lines and loss of grassland habitat are major threats. Its main surviving population is in and around the Desert National Park near Jaisalmer.
42. In which national park were cheetahs reintroduced in India in 2022?
Answer: Kuno National Park, Madhya Pradesh. Eight cheetahs from Namibia were released on 17 September 2022, followed by cheetahs from South Africa in 2023. The cheetah had been declared extinct in India in 1952.
43. Silent Valley National Park, known for its tropical evergreen forests, is in which state?
Answer: Kerala. Silent Valley in the Nilgiri hills was saved from a hydroelectric project after a public campaign. It is an important home of the lion-tailed macaque.
44. With which movement are Sunderlal Bahuguna and Chandi Prasad Bhatt associated?
Answer: The Chipko movement. The Chipko movement began in 1973 in the Chamoli district of present-day Uttarakhand, when villagers hugged trees to stop them being cut. Gaura Devi led the women of Reni village in 1974.
45. Which forest conservation movement of Karnataka was inspired by Chipko?
Answer: The Appiko movement. The Appiko movement started in 1983 in the Uttara Kannada district under Panduranga Hegde. “Appiko” means “to hug” in Kannada.
46. Which community of Rajasthan is famous for sacrificing lives to protect khejri trees?
Answer: The Bishnoi community. In 1730 Amrita Devi Bishnoi and more than 360 others gave their lives at Khejarli near Jodhpur. The Amrita Devi Bishnoi Wildlife Protection Award is named after her.
47. Which were the first two Ramsar sites of India?
Answer: Chilika Lake (Odisha) and Keoladeo National Park (Rajasthan). Both were designated in 1981. Chilika is the largest brackish-water lagoon in India, and Keoladeo near Bharatpur is famous for migratory birds.
48. Which national park in Uttarakhand is famous for its alpine flowers?
Answer: Valley of Flowers National Park. The Valley of Flowers and Nanda Devi National Parks together form a UNESCO World Heritage Site. Both lie in the Chamoli district.
49. Which national park in Assam is a UNESCO World Heritage Site known for tigers, elephants and the pygmy hog?
Answer: Manas National Park. Manas lies on the Bhutan border and is also a tiger reserve, an elephant reserve and a biosphere reserve. Kaziranga is the other natural World Heritage Site in Assam.
50. What is a wildlife corridor?
Answer: A strip of natural habitat that connects two larger habitats. Corridors allow animals such as tigers and elephants to move between protected areas, which prevents inbreeding and reduces human-wildlife conflict.
Pollution and Climate Change (Questions 51 to 75)
51. Which gas leaked in the Bhopal gas tragedy of December 1984?
Answer: Methyl isocyanate (MIC). The gas leaked from the Union Carbide pesticide plant on the night of 2 and 3 December 1984. The disaster led to the Environment (Protection) Act, 1986.
52. Minamata disease is caused by poisoning from which metal?
Answer: Mercury. It was first identified at Minamata in Japan, where people ate fish contaminated by mercury from industrial waste. The Minamata Convention on Mercury was adopted in 2013.
53. Itai-itai disease is caused by which metal?
Answer: Cadmium. Itai-itai, meaning “it hurts, it hurts”, caused severe bone and joint pain in Japan. Cadmium affects the bones and kidneys.
54. Excess of which substance in drinking water causes blue baby syndrome?
Answer: Nitrate. Nitrate reduces the oxygen-carrying capacity of a baby’s blood, a condition called methaemoglobinaemia. Fertiliser run-off is a major source of nitrate in groundwater.
55. Excess of which element in drinking water causes fluorosis?
Answer: Fluoride. Fluorosis causes mottling of teeth and stiffness and deformity of bones. A small amount of fluoride protects teeth, but too much is harmful.
56. Arsenic contamination of groundwater is a serious problem in which delta region of India?
Answer: The Ganga delta, especially West Bengal. Long-term drinking of arsenic-rich water causes skin lesions and cancer. Bihar, Uttar Pradesh and Assam also report arsenic in groundwater.
57. Which gases are mainly responsible for acid rain?
Answer: Sulphur dioxide and nitrogen oxides. These gases form sulphuric and nitric acids in the atmosphere. Rain with a pH below about 5.6 is called acid rain, and it corrodes marble monuments such as the Taj Mahal.
58. Which secondary pollutants are typical of photochemical smog?
Answer: Ozone and peroxyacetyl nitrate (PAN). Photochemical smog forms when nitrogen oxides and hydrocarbons from vehicles react in sunlight. Classical or London smog is a mix of smoke, fog and sulphur dioxide.
59. What does PM2.5 refer to?
Answer: Particulate matter with a diameter of 2.5 micrometres or less. These fine particles can reach deep into the lungs and the bloodstream. PM10 refers to particles of 10 micrometres or less.
60. How many pollutants are considered in India’s National Air Quality Index (AQI)?
Answer: Eight. The pollutants are PM10, PM2.5, nitrogen dioxide, sulphur dioxide, carbon monoxide, ozone, ammonia and lead. The index was launched in 2015 and has six colour-coded categories from Good to Severe.
61. Which greenhouse gas is released in large amounts from paddy fields, wetlands and cattle?
Answer: Methane. Methane is also called marsh gas. It traps much more heat per molecule than carbon dioxide, although it stays in the atmosphere for a shorter time.
62. Over which region was the ozone hole first discovered in 1985?
Answer: Antarctica. Scientists of the British Antarctic Survey reported the seasonal thinning of ozone over Antarctica. It is worst in the southern spring, from September to November.
63. In which unit is the thickness of the ozone layer measured?
Answer: Dobson unit. Most atmospheric ozone lies in the stratosphere. An ozone level below 220 Dobson units is generally treated as an ozone hole.
64. Is ozone near the ground (in the troposphere) useful or harmful?
Answer: Harmful; it is a pollutant. Ground-level ozone irritates the lungs and damages crops. Ozone in the stratosphere, on the other hand, protects life by absorbing ultraviolet radiation.
65. What is carbon sequestration?
Answer: The capture and long-term storage of carbon dioxide. Forests, soils and oceans store carbon naturally. Carbon dioxide can also be captured from power plants and stored underground.
66. One carbon credit is equal to the reduction of how much carbon dioxide?
Answer: One tonne of carbon dioxide or its equivalent. Carbon credits can be traded, so a company that reduces emissions can sell credits to one that exceeds its limit. Carbon trading grew out of the Kyoto Protocol.
67. What is El Niño?
Answer: The unusual warming of surface waters in the central and eastern Pacific Ocean. El Niño years are often linked with a weak Indian monsoon and droughts. La Niña, the cooling of the same waters, usually favours a good monsoon.
68. What is the main cause of coral bleaching?
Answer: A rise in sea-water temperature. Stressed corals expel the zooxanthellae algae living in their tissues and turn white. Ocean acidification and pollution add to the stress.
69. Which is the largest coral reef system in the world?
Answer: The Great Barrier Reef, Australia. In India, coral reefs are found in the Gulf of Mannar, the Gulf of Kachchh, Lakshadweep and the Andaman and Nicobar Islands.
70. In which unit is the loudness of noise measured?
Answer: Decibel (dB). Prolonged exposure to sound above about 80 to 85 dB can damage hearing. Normal conversation is about 60 dB.
71. From which date did India ban identified single-use plastic items?
Answer: 1 July 2022. Items such as plastic cutlery, straws, earbuds with plastic sticks and thin carry bags were banned under the Plastic Waste Management Amendment Rules, 2021.
72. What is bioremediation?
Answer: The use of microorganisms or plants to remove or neutralise pollutants. Ananda Mohan Chakrabarty developed a genetically engineered Pseudomonas bacterium, called the superbug, that could break down oil. Using plants for the same purpose is called phytoremediation.
73. What is thermal pollution of water?
Answer: The rise in water temperature caused by hot water released from industries and power plants. Warm water holds less dissolved oxygen, which harms fish and other aquatic life.
74. Which waste product of coal-based thermal power plants is used to make bricks and cement?
Answer: Fly ash. Fly ash is a fine powder that pollutes air and water if dumped carelessly. Using it in construction reduces both pollution and the need for clay.
75. What is black carbon?
Answer: Fine soot produced by the incomplete burning of fossil fuels, wood and crop residue. Black carbon absorbs sunlight and warms the atmosphere. When it settles on snow and glaciers it speeds up melting, which is a concern for the Himalaya.
Environmental Laws, Conventions and Institutions (Questions 76 to 100)
76. Where was the first UN Conference on the Human Environment held in 1972?
Answer: Stockholm, Sweden. The Stockholm Conference led to the creation of the United Nations Environment Programme (UNEP) in 1972, with its headquarters at Nairobi, Kenya.
77. On which date is World Environment Day observed?
Answer: 5 June. It marks the opening day of the Stockholm Conference and has been observed since 1973. Earth Day is observed on 22 April.
78. Where was the Earth Summit held in 1992?
Answer: Rio de Janeiro, Brazil. The Earth Summit opened the UN Framework Convention on Climate Change (UNFCCC) and the Convention on Biological Diversity (CBD) for signature and adopted Agenda 21.
79. In which year was the Kyoto Protocol adopted?
Answer: 1997. The Kyoto Protocol set binding emission-reduction targets for developed countries and came into force in 2005. It introduced the Clean Development Mechanism.
80. What is the main temperature goal of the Paris Agreement of 2015?
Answer: To keep global warming well below 2 °C above pre-industrial levels and try to limit it to 1.5 °C. The Paris Agreement was adopted at COP21. Each country sets its own climate targets, called Nationally Determined Contributions (NDCs).
81. The Ramsar Convention of 1971 deals with the conservation of what?
Answer: Wetlands. It was signed at Ramsar in Iran. World Wetlands Day is observed on 2 February, the date the convention was signed.
82. Which convention regulates international trade in endangered wild animals and plants?
Answer: CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora). CITES was signed in Washington, D.C. in 1973. World Wildlife Day on 3 March marks the date it was signed.
83. The Cartagena Protocol under the Convention on Biological Diversity deals with what?
Answer: Biosafety, especially the safe movement of living modified (genetically modified) organisms. The Cartagena Protocol was adopted in 2000. The Nagoya Protocol of 2010 deals with access to genetic resources and the fair sharing of benefits from their use.
84. Which convention controls the movement of hazardous waste across national borders?
Answer: The Basel Convention. It was adopted in 1989 to stop developed countries from dumping hazardous waste in developing countries.
85. The Stockholm Convention of 2001 deals with which pollutants?
Answer: Persistent organic pollutants (POPs). POPs such as DDT, aldrin and dioxins do not break down easily and build up in food chains. The Rotterdam Convention deals with prior informed consent for trade in hazardous chemicals.
86. Which international treaty was signed in 1987 to protect the ozone layer?
Answer: The Montreal Protocol. It phases out ozone-depleting substances such as CFCs and halons. The Kigali Amendment of 2016 added the phase-down of hydrofluorocarbons (HFCs). International Ozone Day is observed on 16 September.
87. Which bodies set up the Intergovernmental Panel on Climate Change (IPCC) in 1988?
Answer: The World Meteorological Organization (WMO) and UNEP. The IPCC assesses the science of climate change through its assessment reports. It shared the Nobel Peace Prize in 2007 with Al Gore.
88. In which year was the Wildlife (Protection) Act passed in India?
Answer: 1972. The Act provides for national parks, sanctuaries and schedules of protected species. It was amended in 2022 to bring Indian law in line with CITES.
89. Which umbrella law on the environment was passed in India after the Bhopal gas tragedy?
Answer: The Environment (Protection) Act, 1986. It gives the central government wide powers to protect and improve the environment. Its preamble refers to the decisions taken at the 1972 Stockholm Conference.
90. Under which Act was the Central Pollution Control Board (CPCB) set up?
Answer: The Water (Prevention and Control of Pollution) Act, 1974. The Air (Prevention and Control of Pollution) Act followed in 1981, and the CPCB was given functions under it as well.
91. In which year was the Forest (Conservation) Act passed?
Answer: 1980. The Act requires the central government’s approval before forest land is used for non-forest purposes. In 2023 it was renamed the Van (Sanrakshan Evam Samvardhan) Adhiniyam, 1980.
92. In which year was the National Green Tribunal (NGT) established?
Answer: 2010. The NGT was set up under the National Green Tribunal Act, 2010 to decide environmental cases quickly. Its principal bench is in New Delhi.
93. Where is the headquarters of the National Biodiversity Authority?
Answer: Chennai. The National Biodiversity Authority was set up in 2003 under the Biological Diversity Act, 2002. States have State Biodiversity Boards.
94. Which Article of the Constitution directs the State to protect and improve the environment and safeguard forests and wildlife?
Answer: Article 48A. Article 48A, a Directive Principle, and Article 51A(g), a Fundamental Duty, were added by the 42nd Amendment of 1976. The Supreme Court has read the right to a clean environment into Article 21.
95. How many national missions are there under India’s National Action Plan on Climate Change (NAPCC)?
Answer: Eight. The NAPCC was released in 2008. Its missions include the National Solar Mission, the National Mission for Enhanced Energy Efficiency and the National Mission for a Green India.
96. Where is the headquarters of the International Solar Alliance?
Answer: Gurugram, Haryana (India). The International Solar Alliance was launched by India and France in 2015 at COP21 in Paris. It was the first treaty-based international organisation to have its headquarters in India.
97. On which date is the International Day for Biological Diversity observed?
Answer: 22 May. It marks the adoption of the agreed text of the Convention on Biological Diversity in 1992. World Forestry Day (International Day of Forests) is observed on 21 March.
98. Which global mass movement for sustainable living did India launch in 2022?
Answer: Mission LiFE (Lifestyle for Environment). The idea was put forward by India at COP26 in Glasgow in 2021, and the mission was launched in October 2022 at Ekta Nagar in Gujarat with the UN Secretary-General.
99. By which year has India pledged to reach net-zero emissions?
Answer: 2070. The net-zero target was announced at COP26 in Glasgow in 2021 as part of India’s five-point “Panchamrit” climate action plan.
100. Which institution publishes the India State of Forest Report every two years?
Answer: The Forest Survey of India, Dehradun. The report uses satellite data to estimate forest and tree cover. Madhya Pradesh has the largest forest cover by area among Indian states.
Quick Revision Tips
- Make one table of national parks and the animals they are famous for: Kaziranga (one-horned rhinoceros), Gir (Asiatic lion), Keibul Lamjao (sangai deer), Kuno (cheetah), Sundarbans (Royal Bengal tiger in mangroves) and Silent Valley (lion-tailed macaque). Park-and-animal matches are among the most common questions.
- Keep a timeline of environmental laws in India: Wildlife (Protection) Act 1972, Water Act 1974, Forest (Conservation) Act 1980, Air Act 1981, Environment (Protection) Act 1986, Biological Diversity Act 2002 and National Green Tribunal Act 2010.
- Learn international conventions as pairs of name and subject: Ramsar (wetlands), CITES (trade in endangered species), Montreal (ozone layer), Kyoto and Paris (climate change), Basel (hazardous waste), Stockholm 2001 (persistent organic pollutants) and Cartagena (biosafety).
- Revise pollutants with the diseases they cause: mercury (Minamata), cadmium (itai-itai), nitrate (blue baby syndrome), fluoride (fluorosis) and arsenic (skin lesions and cancer). Examiners often give the disease and ask for the pollutant.
- Write down important environment days in calendar order: World Wetlands Day 2 February, World Wildlife Day 3 March, International Day of Forests 21 March, Earth Day 22 April, Biodiversity Day 22 May, World Environment Day 5 June and Ozone Day 16 September.
Conclusion
Environment and Ecology questions are mostly direct and factual, so steady revision brings quick marks. If you can recall these 100 questions, you will have covered a large share of the static environment portion asked in NDA, CDS, AFCAT, UPSC, SSC and state PSC papers. Read this list along with the ecology chapters of NCERT Biology, keep a separate note of new Ramsar sites, tiger reserves and climate conferences from current affairs, and come back to the sections where you made mistakes.
FAQs
1. How many Environment and Ecology questions are asked in NDA, CDS and AFCAT?
The number changes from paper to paper, so it is better not to prepare for a fixed count. Environment questions appear regularly in the NDA General Ability Test, the CDS General Knowledge paper and AFCAT general awareness, often mixed with geography and general science.
2. Which NCERT books are useful for Environment and Ecology GK?
The ecology chapters of Class 12 Biology (Organisms and Populations, Ecosystem, Biodiversity and Conservation) are the most useful, along with the Class 8 and Class 10 science chapters on natural resources and our environment, and the Class 11 geography chapters on biodiversity.
3. Which topics of Environment are most important for defence exams?
Ecosystems and food chains, national parks and their famous animals, biosphere reserves, endangered species, pollution and its effects, the ozone layer, climate change, environmental laws of India and international conventions are the most frequently asked areas.
4. How should I prepare current affairs related to the environment?
Keep a monthly note of new Ramsar sites, tiger reserves, newly discovered species, climate conferences (COP meetings) and new environment rules. Link each new fact to the static fact you already know, such as the convention or law behind it.
5. How should I revise these 100 Environment GK questions?
Read one section at a time, cover the answers and test yourself, then mark the questions you got wrong. Revise the marked questions again after two or three days, and use the Quick Revision Tips tables for last-minute revision before the exam.
