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Every NCERT book that matters for UPSC — open a book, then a chapter. Learn each chapter's concepts, then how UPSC tests them — with diagrams, flowcharts and the past questions to attempt.
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← Fundamentals of Physical Geography — all chaptersBiodiversity and Conservation
Start here: why this chapter matters
In simple wordsImagine a library where every book is a kind of living thing — some we have read, most we have not, and some are burning before anyone opened them. Biodiversity is that library of life. This chapter asks: how big is it, where is it richest, why does it matter, why is it shrinking, and how can we save it?
This is the last chapter of the book and the only one in Unit VI, ‘Life on the Earth’. It ties the book together: NCERT reminds you of Chapter 5's weathering mantle (Figure 5.2) — deepest where sunshine and water are plentiful — which supports the richest vegetation and hence the richest biodiversity. Solar energy and water are the basic inputs; areas rich in both have the widest spectrum of life.
- Builds on Chapter 5 (weathering mantle and soils) and the climate chapters (Unit IV).
- Links to Class 11 India: Physical Environment (natural vegetation, protected areas, biosphere reserves) and to environment and ecology for GS3.
- UPSC: one of the most-asked areas. Prelims tests hotspots, threats to biodiversity, the latitudinal gradient, IUCN and the Red List, in-situ conservation and biosphere reserves. Mains: biodiversity variation in India and the Biological Diversity Act (GS3 2018), vegetation diversity and wildlife sanctuaries (GS1 2023), the Kunming–Montreal framework (GS3 2026).
| Word | What it means here |
|---|---|
| Species | A group of organisms with similar physical characteristics that breed among themselves |
| Gene | The basic building block of inherited characteristics |
| Ecosystem | Living things plus their physical surroundings, working together |
| Habitat | The natural home of a species |
| Endemic | Found naturally in one place and nowhere else |
| Exotic species | A species introduced into a habitat where it is not a natural inhabitant |
| Extinction | The disappearance of a species for ever |
| Hotspot | An area very rich in species (and, in the modern definition, in endemic species under threat) |
| Agro-biodiversity | Crop diversity — the variety of crops and their varieties |
At a glance — the six ideas to carry away
- Biodiversity = variety of life — genes, species and ecosystems; ~10 million species is the best estimate.
- Three levels: genetic (within a species), species (number and variety), ecosystem (habitats and processes).
- Richest in the tropics; towards the poles, larger populations of fewer species.
- Roles: ecological, economic, scientific — and an ethical duty to let species exist.
- Loss: population pressure, deforestation, calamities, pollutants, exotic species, poaching. IUCN: endangered, vulnerable, rare.
- Conservation: Wild Life (Protection) Act 1972, CBD (Rio, 1992), 12 megadiversity countries, hotspots.
1. What is biodiversity, and where is it richest?
In simple words‘Bio’ = life, ‘diversity’ = variety. Walk through a rain forest and you may see hundreds of kinds of trees in a few hectares; walk across the Arctic tundra and you may see the same few kinds of moss and the same herd of reindeer for kilometres. That contrast is the heart of this chapter.
Biodiversity is the number and variety of organisms found within a specified region — the varieties of plants, animals and micro-organisms, the genes they contain and the ecosystems they form; it covers variability within and between species and within and between ecosystems. It is our living wealth, the result of hundreds of millions of years of evolution.
| Fact (NCERT) | Value |
|---|---|
| Biodiversity today is the result of | 2.5–3.5 billion years of evolution |
| Number of species on earth | 2 million to 100 million; 10 million is the best estimate |
| Unclassified species example | About 40% of South America's freshwater fishes are not yet classified |
| Average ‘half-life’ of a species | 1 to 4 million years |
| Species that ever lived and are now extinct | 99% |
| Before humans | The earth supported more biodiversity than in any other period; since the emergence of humans it has declined rapidly |
Biodiversity is not even: it is consistently richer in the tropics, and tropical forests are very rich. As one approaches the poles, one finds larger and larger populations of fewer and fewer species.
Beyond NCERTBiodiversity also usually falls with altitude along mountain slopes, for the same reasons — less energy and harsher conditions (UPSC 2011: both latitude and altitude statements were correct). India has only about 2.4% of the world's land but about 7–8% of its recorded species.
Exam trapBiodiversity is richer in tropical regions (exercise Q1-iv), not polar, temperate or ocean regions. UPSC 1993 picked NCERT's ‘about ten million species’ as the best estimate.
2. Three levels of biodiversity
In simple wordsThink of a city. Within one family, children look different from each other (genetic diversity). The city has many different families and communities (species diversity). And the city has many kinds of neighbourhood — markets, parks, riversides, old town (ecosystem diversity).
| Level | Meaning (NCERT) | Example |
|---|---|---|
| Genetic diversity | Variation of genes within a species; essential for healthy breeding of populations | Humans (Homo sapiens) differ in height, colour and appearance |
| Species diversity | Variety and number of species in a defined area; measured by richness, abundance and types. Areas rich in species are hotspots | A tropical forest vs a pine plantation |
| Ecosystem diversity | Broad differences between ecosystem types and the diversity of habitats and ecological processes within each; boundaries of communities and ecosystems are not rigid, so demarcation is difficult | Grasslands and sholas side by side (Figure 14.1) |
Reading NCERT Figure 14.1 — Grasslands and sholas, Indira Gandhi National Park, Annamalai (page 116)
- A black-and-white photo of rolling, smooth, grass-covered hills, with dark, dense patches of shola forest tucked into the folds and valleys between them, and a forested slope in the foreground.
- The point: two quite different ecosystems — grassland and forest — sit side by side in one landscape, with a sharp edge between them. That is ecosystem diversity.
- Beyond NCERT: sholas are stunted tropical montane evergreen forests found in sheltered valleys of the high hills of the southern Western Ghats (Nilgiris, Anamalai, Palani), surrounded by montane grasslands. The park is now part of the Anamalai Tiger Reserve, Tamil Nadu.
Exam trapDifferences in height and colour among humans are genetic diversity (within one species), not species diversity. NCERT points to ‘Figure 14.5’ for hotspots and to ‘the ecosystem chapter’ — neither exists in the current book (see the inconsistencies box in section 6).
3. Why biodiversity matters
In simple wordsAn aeroplane wing is held together by thousands of rivets. Pop out one and nothing happens; pop out a hundred and the wing may fail. Each species is a rivet in the ecosystem — we rarely know which one is holding things together until it is gone.
Biodiversity has shaped human culture, and human communities have shaped nature's diversity at genetic, species and ecological levels. NCERT names three roles — ecological, economic and scientific — and adds an ethical argument.
| Role | What NCERT says |
|---|---|
| Ecological | Every species performs some function: species capture and store energy, produce and decompose organic matter, cycle water and nutrients, fix atmospheric gases and help regulate climate. Every organism, besides taking, contributes something to others. The more diverse an ecosystem, the better its species survive adversities, the more productive and more stable it is — loss of species reduces its ability to maintain itself |
| Economic | A reservoir of resources for food, pharmaceuticals and cosmetics: food crops, livestock, forests, fish, medicinal resources. Crop diversity = agro-biodiversity. This ‘resource’ view also drives deterioration of biodiversity and creates conflicts over sharing and appropriating natural resources |
| Scientific | Each species gives clues to how life evolved and will evolve, how life functions and each species' role in sustaining ecosystems — of which we are also a species |
| Ethical | Every species has an intrinsic right to exist; it is morally wrong to cause extinction voluntarily. The level of biodiversity indicates the state of our relationship with other species; it is part of many human cultures |
⤵ Why diversity means stability
Many species, each with a roleenergy capture, decomposition, nutrient and water cycling
Several species can do similar jobsif one fails, another can partly take over
The ecosystem survives shocksadversities, attacks, environmental change
More stable and more productiveNCERT: the more variety, the more stable
Loss of species → weaker systemless able to maintain itself
NCERT's question: how do humans contribute to ecosystems?Positively, through planting and protecting forests, managing sacred groves and community forests, traditional farming that conserves seed varieties (agro-biodiversity), recycling nutrients through manure and composting, and conservation laws and protected areas. NCERT's point is that, like every species, we should give back as well as take.
Exam trapBiodiversity underpins human existence through soil formation, prevention of soil erosion, recycling of waste and pollination of crops — all four (UPSC 2011). Conservation of biodiversity matters for all organisms (exercise Q1-i), not just plants or animals.
4. Loss of biodiversity
In simple wordsA house can fall because of an earthquake (a natural blow), because termites eat its beams slowly (pollution and invasive species), because the family keeps selling bricks (over-use), or because burglars strip it (poaching). Biodiversity is losing to all four at once — and humans drive most of them.
| Cause (NCERT) | How it destroys biodiversity |
|---|---|
| Population growth and consumption | Faster use of natural resources has accelerated loss of species and habitats; tropics bear the heaviest pressure |
| Over-exploitation and deforestation | Rampant in the tropics; since tropical rain forests hold about half of all species, habitat destruction is disastrous for the whole biosphere |
| Natural calamities | Earthquakes, floods, volcanic eruptions, forest fires, droughts damage flora and fauna and change local biodiversity |
| Pesticides and pollutants | Hydrocarbons and toxic heavy metals destroy weak and sensitive species |
| Exotic species | Species introduced into a habitat where they are not natural inhabitants; many natural communities have been badly damaged by them (e.g. Hawaii's unique species) |
| Poaching | Tigers, elephants, rhinoceros, crocodiles, minks and birds hunted for horns, tusks and hides — pushing them into the endangered category |
⤵ From pressure to extinction
More people, more consumptionespecially in the species-rich tropics
Habitat destroyed or broken updeforestation, farming, settlements
Species directly harmedpoaching, pollutants, exotic species
Populations shrinkrare → vulnerable → endangered
Genetic diversity fallsless healthy breeding
Extinctionand weaker, less stable ecosystems
Beyond NCERT
- Indian examples of harmful exotic (invasive) species: Lantana camara, water hyacinth, Parthenium and Prosopis juliflora (UPSC 2018 asked why Prosopis is in the news — it reduces local biodiversity).
- Scientists speak of a ‘sixth mass extinction’ driven by human over-exploitation, habitat fragmentation and climate change (UPSC 2018). Global warming and habitat fragmentation are also counted as threats (UPSC 2012).
- India's vultures crashed in the 1990s–2000s after eating carcasses of cattle treated with the painkiller diclofenac — a pollutant example.
Exam trapAn exotic species is one introduced from elsewhere (exercise 2-v) — not necessarily rare or beautiful. Creating biosphere reserves protects biodiversity; destruction of habitats and shifting cultivation threaten it (UPSC 1993).
5. IUCN categories and the Red List
In simple wordsA hospital sorts patients by how serious their condition is, so that the sickest get help first. The IUCN does the same for species — sorting them by how close they are to extinction.
The International Union for Conservation of Nature and Natural Resources (IUCN) has classified threatened species of plants and animals into three categories for conservation:
| NCERT category | Meaning |
|---|---|
| Endangered | In danger of extinction. IUCN publishes worldwide information on them as the Red List of threatened species |
| Vulnerable | Likely to be in danger of extinction in the near future if threats continue; survival not assured as population has fallen greatly |
| Rare | Very small world population; confined to limited areas or thinly scattered over a wide area |
Reading NCERT Figure 14.2 — Red Panda, an endangered species (page 117)
- A photo of two red pandas resting on a tree trunk and branches: cat-sized, with pale white face markings, rounded ears, dense fur and a long, thick, ringed tail.
- They live in trees — showing why loss of forest habitat is the main threat to such species.
- Beyond NCERT: the red panda lives in the temperate forests of the eastern Himalaya (in India: Sikkim, Arunachal Pradesh, northern West Bengal); it is the state animal of Sikkim and is listed as Endangered on the IUCN Red List. UPSC 2007 tested that it is not found only in the western Himalaya.
Beyond NCERT — IUCN and CITESIUCN (founded 1948, headquarters Gland, Switzerland) is not a UN organ; it is a union of governments and civil-society organisations that runs field projects and sets the global Red List standard. CITES (signed 1973) is a treaty between governments regulating international trade in wild animals and plants — exactly NCERT's step (vi) — and it is legally binding on its parties (UPSC 2015).
Exam trapThreatened species are those in danger of extinction (exercise Q1-ii). The Red Data Book/Red List lists threatened species — not endemic species of hotspots, nor protected sites (UPSC 2011).
6. Conservation, megadiversity and hotspots
In simple wordsIf your house is on fire, you save the most precious things first and call the neighbours to help. Conservation works the same way: protect the richest and most threatened places first (hotspots), and involve the local people who live there.
Biodiversity is vital for human existence: all forms of life are so linked that disturbing one unbalances others. Endangered species mean a degraded environment that may threaten our own existence. NCERT stresses education for environment-friendly, sustainable living, and that conservation with sustainable use is possible only with local communities and local institutions — the real problem is keeping the process of conservation going.
India, with 155 other nations, signed the Convention on Biological Diversity at the Earth Summit, Rio de Janeiro, Brazil, June 1992. The World Conservation Strategy suggests these steps:
⤵ World Conservation Strategy — six steps (NCERT)
(i) Preserve endangered speciesmake efforts to save those in danger
(ii) Plan and manage to prevent extinction
(iii) Preserve varieties and wild relativesfood crops, forage plants, timber trees, livestock, animals
(iv) Identify and protect habitats of wild relativeseach country
(v) Safeguard feeding, breeding, resting and nursing habitats
(vi) Regulate international trade in wild plants and animals
In India, the Wild Life (Protection) Act, 1972 was passed to protect, preserve and propagate species within natural boundaries: national parks and sanctuaries were established and biosphere reserves declared (details in India: Physical Environment).
Reading NCERT Figure 14.3 — Humboldtia decurrens (page 118)A close-up photo of a cluster of pale flowers with long, curving petals and stamens among dark leaves on a branch. The caption calls it a highly rare endemic tree of the southern Western Ghats — an example of a rare and endemic species: found nowhere else and in small numbers, so the loss of its small forest habitat could wipe it out. (The caption misspells the genus as ‘Humbodtia’; it is Humboldtia.)
Megadiversity centres. Some countries, mostly in the tropics, hold a large share of the world's species. NCERT lists 12: Mexico, Colombia, Ecuador, Peru, Brazil, Democratic Republic of Congo, Madagascar, China, India, Malaysia, Indonesia and Australia.
Hotspots. To concentrate resources where they are most needed, certain areas were identified as biodiversity hotspots. They are defined by their vegetation, because plants determine an ecosystem's primary productivity. Most hotspots support people who depend on species-rich ecosystems for food, firewood, cropland and timber income. In Madagascar, about 85% of plants and animals are found nowhere else. Hotspots in wealthy regions face other pressures: Hawaii's unique species are threatened by introduced species and land development.
Reading NCERT Figure 14.4 — Some ecological ‘hotspots’ in the world (page 119)
- A world map (scale bar 0–2,000–6,000 km) with shaded patches and labels for 17 areas: Central American Highland Forests, Central American Lowland Forests, Western Ecuador and Colombian Chocó, Tropical Andes, Atlantic Forest (Brazil), Upper Guinean Forests, Eastern Arc Mountains (Tanzania), Eastern Madagascar, Western Ghats (India), Sinharaja Forest (Sri Lanka), Eastern Himalaya, Peninsular Malaysia, Philippines, Northern Borneo, Indonesia, Queensland, Melanesia (New Caledonia).
- Almost every patch lies between the tropics, with a dotted equator running through the middle — the map backs up ‘biodiversity is richer in the tropics’.
- Two of the patches are in India (Western Ghats, Eastern Himalaya) and one is just south of it (Sinharaja).
- The map shows an early list of hotspots, of the kind first drawn up around 1990; today's official list is longer and the boundaries are different (see the Beyond NCERT box).
Beyond NCERT — the modern hotspot and megadiversity lists
- The hotspot idea came from the British ecologist Norman Myers (1988) and was taken up by Conservation International. A hotspot must have at least 1,500 endemic vascular plant species and have lost at least 70% of its original habitat — so the key criteria are species richness, endemism and threat (UPSC 2011).
- There are 36 recognised hotspots worldwide — some outside the tropics, e.g. the Mediterranean Basin (UPSC 2010: hotspots are not only tropical).
- India has 4: the Himalaya, Indo-Burma, Western Ghats and Sri Lanka, and Sundaland (which includes the Nicobar Islands). UPSC 2010's list with ‘Western Himalayas’ and ‘Andaman and Nicobar Islands’ was wrong.
- The commonly cited list of megadiverse countries (Conservation International) has 17 countries, including India and the USA.
- India's Biological Diversity Act, 2002 (National Biodiversity Authority, State Biodiversity Boards, local Biodiversity Management Committees) implements the CBD. The CBD's three objectives: conservation, sustainable use and fair and equitable sharing of benefits from genetic resources. Its Kunming–Montreal Global Biodiversity Framework (2022) includes the ‘30 by 30’ target — protecting 30% of land and sea by 2030.
- Biosphere reserves combine conservation with the traditional life of local people (core, buffer and transition zones) — UPSC 2014 called them the most important strategy for conserving biodiversity together with traditional human life.
NCERT inconsistencies to know
- The text sends you to ‘Figure 14.5’ (species diversity) and to ‘Figure 14.1’ (hotspots) — the hotspot map is actually Figure 14.4; Figure 14.1 is the shola photo and there is no Figure 14.5.
- NCERT says IUCN identified the hotspots; the concept is Norman Myers's and the list is maintained by Conservation International.
- NCERT's ‘rare’ category is from IUCN's older system; today's Red List uses CR, EN, VU and others.
- The text refers to ‘the ecosystem chapter’ studied earlier — that chapter has been removed from the current book.
- Spellings: ‘Columbia’ should be Colombia; ‘Humbodtia’ should be Humboldtia.
Exam trapThe Earth Summit (1992) was held in Rio de Janeiro, Brazil (exercise Q1-v); national parks and sanctuaries exist for conservation (Q1-iii). A botanical garden is ex-situ, not in-situ (UPSC 2011). The Eastern Himalaya is a hotspot region; north-western Australia is not (UPSC 2009).
NCERT exercise — answer outlines
The five multiple-choice questions are in the Self-check below. Try each written question yourself first, then open the outline to compare.
2(i) What is biodiversity? (30 words)
The number and variety of organisms — plants, animals, micro-organisms — in a region, the genes they carry and the ecosystems they form; variability within and between species and ecosystems.
2(ii) What are the different levels of biodiversity? (30 words)
Genetic (variation of genes within a species), species (number and variety of species in an area) and ecosystem diversity (variety of ecosystems, habitats and ecological processes).
2(iii) What do you understand by ‘hotspots’? (30 words)
Areas exceptionally rich in species, identified to concentrate conservation where most needed; defined by their vegetation; usually with many endemic species under threat — e.g. Western Ghats, Eastern Himalaya, Madagascar.
2(iv) Discuss briefly the importance of animals to human kind. (30 words)
Food (meat, milk, fish, eggs), draught power and transport, wool, leather and other raw materials, medicines, pollination and seed dispersal, pest control, soil fertility (earthworms, manure), ecological balance, cultural and religious value, and tourism.
2(v) What do you understand by ‘exotic species’? (30 words)
Species that are not natural inhabitants of a habitat but are introduced into it; they often spread unchecked and damage natural communities — e.g. Lantana, water hyacinth in India (Beyond NCERT examples).
3(i) What are the roles played by biodiversity in the shaping of nature? (150 words)
Intro: biodiversity is our living wealth from billions of years of evolution; it and human culture have shaped each other.
Ecological: species capture and store energy, produce and decompose organic matter, cycle water and nutrients, fix gases, regulate climate; diverse ecosystems are more productive, stable and resilient.
Economic: food crops (agro-biodiversity), livestock, forests, fish, medicines, cosmetics — but over-use and conflicts over appropriation follow.
Scientific: clues to evolution and how life functions.
Ethical/cultural: each species' intrinsic right to exist; biodiversity in human cultures.
Conclude: nature's balance depends on diversity; losing species weakens the whole system. A small diagram of the four roles helps.
Ecological: species capture and store energy, produce and decompose organic matter, cycle water and nutrients, fix gases, regulate climate; diverse ecosystems are more productive, stable and resilient.
Economic: food crops (agro-biodiversity), livestock, forests, fish, medicines, cosmetics — but over-use and conflicts over appropriation follow.
Scientific: clues to evolution and how life functions.
Ethical/cultural: each species' intrinsic right to exist; biodiversity in human cultures.
Conclude: nature's balance depends on diversity; losing species weakens the whole system. A small diagram of the four roles helps.
3(ii) What are the major factors responsible for the loss of biodiversity? What steps are needed to prevent them? (150 words)
Factors: population growth and consumption (tropics: ¼ of land, ¾ of people, ½ of species in rain forests); over-exploitation and deforestation; natural calamities (earthquakes, floods, fires, droughts); pesticides and pollutants (hydrocarbons, heavy metals); exotic species; poaching for horns, tusks, hides.
Steps (World Conservation Strategy): preserve endangered species; plan and manage to prevent extinction; preserve crop, forage, timber and livestock varieties and wild relatives; protect habitats of wild relatives and where species feed, breed, rest and nurse young; regulate international wildlife trade.
India: Wild Life (Protection) Act 1972 — national parks, sanctuaries, biosphere reserves; CBD (Rio 1992).
Also: education, sustainable use, local community participation and institutions; focus on hotspots and megadiversity centres.
Steps (World Conservation Strategy): preserve endangered species; plan and manage to prevent extinction; preserve crop, forage, timber and livestock varieties and wild relatives; protect habitats of wild relatives and where species feed, breed, rest and nurse young; regulate international wildlife trade.
India: Wild Life (Protection) Act 1972 — national parks, sanctuaries, biosphere reserves; CBD (Rio 1992).
Also: education, sustainable use, local community participation and institutions; focus on hotspots and megadiversity centres.
Project work: national parks, sanctuaries and biosphere reserves of your state on a map
List them from your state forest department or India: Physical Environment; mark each on an outline map of India with a legend (national park, sanctuary, biosphere reserve); note one flagship species for each; check whether any lies in a hotspot (Western Ghats, Himalaya, North-East, Nicobar).
What to remember
Numbers
Years of evolution behind today's biodiversity2.5–3.5 billion
Estimated number of species2–100 million; best estimate 10 million
Unclassified South American freshwater fishes~40%
Average half-life of a species1–4 million years
Species that ever lived, now extinct99%
Levels of biodiversity3
Tropics: share of world area~one-fourth
Tropics: share of human population~three-fourths
Tropical rain forests: share of species~50%
NCERT's IUCN categories3 — endangered, vulnerable, rare
Madagascar species found nowhere else~85%
Megadiversity countries (NCERT)12
Nations signing the CBD with India at Rio155 others
Earth SummitRio de Janeiro, June 1992
Wild Life (Protection) Act1972
World Conservation Strategy steps6
Hotspots marked in Figure 14.417
One-liners
- Biodiversity = genes + species + ecosystems.
- Tropics: many species; poles: larger populations of fewer species.
- Genetic diversity is essential for healthy breeding.
- The more diverse an ecosystem, the more stable and productive.
- Agro-biodiversity = crop diversity.
- Exotic species = introduced, not native.
- IUCN publishes the Red List of threatened species.
- Hotspots are defined by their vegetation.
- Conservation needs local communities.
Traps to avoid
- Biodiversity is richest in the tropics, not the oceans or temperate zones.
- Human differences in height and colour = genetic diversity.
- Rain forests hold about half the species on only part of the land.
- Botanical gardens and zoos are ex-situ; national parks, sanctuaries and biosphere reserves are in-situ.
- The Red List covers threatened species, not protected sites.
- Hotspots are not only tropical (Beyond NCERT: the Mediterranean Basin is one).
- India's hotspots: Himalaya, Indo-Burma, Western Ghats–Sri Lanka, Sundaland — not ‘Western Himalaya’ or ‘Andaman and Nicobar’.
- IUCN is not a UN body; CITES is a treaty between governments.
- NCERT's hotspot map is Figure 14.4, though the text says 14.1 and 14.5.
How to strategise
Prelims — what UPSC asks
- Hotspots are the single most-asked item: which Indian region is a hotspot (1996), which regions are hotspots (2009), whether hotspots are only tropical and how many India has (2010), the criteria — richness, endemism, threat (2011). Learn India's four and the definition.
- NCERT lines turn into options: ‘about ten million species’ (1993); biodiversity richer at lower latitudes (and lower altitudes) (2011); habitat destruction threatens biodiversity (1993); threats include global warming, fragmentation and invasive species (2012); the ‘sixth extinction’ (2018).
- Conservation tools: botanical gardens are not in-situ (2011); biosphere reserves conserve biodiversity together with traditional human life (2014); the Red List contains threatened species (2011); IUCN vs CITES (2015).
- Roles of biodiversity: soil formation, erosion control, waste recycling, pollination (2011).
- Beyond this chapter, UPSC asks many species-in-news and protected-area-location questions — prepare those from current affairs and the India geography book; they are not linked here.
Mains — where it appears and how to answer
- GS3: how biodiversity varies in India and how the Biological Diversity Act, 2002 helps conserve it (2018); the aims of the Kunming–Montreal Global Biodiversity Framework and India's commitments (2026).
- GS1: factors behind the diversity of natural vegetation in India and the significance of wildlife sanctuaries in rainforest regions (2023).
- Answer frame: define (three levels) → distribution (tropics, hotspots, megadiversity; India's share) → importance (four roles) → threats (NCERT's six causes + climate change) → conservation (in-situ, ex-situ, laws, CBD, community participation) → way forward.
- Use a small map of India's hotspots or a levels diagram; quote NCERT's numbers (¼ area, ¾ people, ½ species).
Self-check
Tap an option. NCERT's own exercise questions come first; the rest test the figures and common confusions.
1. Conservation of biodiversity is important for:
2. Threatened species are those which:
3. National parks and sanctuaries are established for the purpose of:
4. Biodiversity is richer in:
5. In which one of the following countries was the ‘Earth Summit’ held?
6. Variation in height and skin colour among human beings is an example of…
7. Which one of the following is NOT an in-situ method of conservation?
8. According to NCERT, tropical rain forests contain about what share of the earth's species?
UPSC questions from this chapter
Open any question to attempt it in the Question bank — your attempt is saved to your progress.