Study this in the app →

English · हिन्दी · తెలుగు · தமிழ் · മലയാളം · मराठी · ಕನ್ನಡ

What biodiversity is and where it is found

తెలుగులో వివరణ

Biodiversity · Part 1 / 2 · Fact-checked on · how we check

Written with AI from the sources listed at the bottom of this page, then fact-checked by a separate AI.

The CBD definition and the three levels of biodiversity; species richness and evenness, alpha, beta and gamma diversity; the latitudinal gradient and the species–area relationship; India as a megadiverse country; biodiversity hotspots and India's four; the ten biogeographic zones; endemic species.

Each idea is explained first in Telugu (తెలుగు), ending with the English and Hindi exam terms, followed by the same point in exam English. UPSC Prelims is in English or Hindi, so understand it in Telugu and revise it in English.

పర్యావరణ వ్యవస్థలు ఎలా పనిచేస్తాయో చూశాం. ఇప్పుడు వాటిలో ఎంత జీవం ఉంది, ఎక్కడ ఎక్కువ, ఎందుకు ప్రమాదంలో ఉంది అనేది. జీవవైవిధ్యం అంటే మన చుట్టూ ఉన్న రకరకాల ప్రాణుల సంపద. ఈ భాగంలో: దాని అర్థం, మూడు స్థాయిలు, కొలవడం, ఎక్కడ ఎక్కువ, భారతదేశం ఎందుకు సంపన్న దేశం, హాట్‌స్పాట్లు, జీవ భౌగోళిక మండలాలు. (→ English: biodiversity · हिन्दी: जैव विविधता)

In exam EnglishThe ecology chapter showed how ecosystems work. This chapter asks how much life they hold, where it is concentrated and why it is in danger. biodiversity is a word the Prelims returns to almost every year, through hotspots, endemic species, the IUCN Red List, protected areas and the treaties that protect nature. This first part builds the base: what biodiversity means and its three levels, how ecologists measure it, why it is spread so unevenly over the globe, why India counts among the richest countries, which parts of India are global hotspots, and how the country is divided into biogeographic zones. Part 2 turns to the value of biodiversity, the threats it faces, the Red List and the ways it is conserved.

జీవవైవిధ్యానికి మూడు స్థాయిలు. జన్యు వైవిధ్యం: ఒకే జాతిలో రకాలు, మన ఊళ్ళో ఎన్నో రకాల వరి, ఎన్నో జాతుల ఆవులు ఉన్నట్టు. జాతుల వైవిధ్యం: ఒక చోట ఎన్ని వేర్వేరు జాతులు ఉన్నాయి. పర్యావరణ వ్యవస్థల వైవిధ్యం: అడవి, గడ్డి మైదానం, చిత్తడి నేల, మడ అడవి, పగడపు దిబ్బలు. ఒక పెట్టెలో చిన్న పెట్టెలు ఉన్నట్టు, ఇవి ఒకదానిలో ఒకటి ఉంటాయి. (→ English: genetic diversity; species diversity; ecosystem diversity · हिन्दी: आनुवंशिक विविधता; प्रजाति विविधता; पारिस्थितिकी तंत्र विविधता)

In exam EnglishBiodiversity is short for biological diversity, the variety of all life on Earth. The Convention on Biological Diversity (1992), in its Article 2, defines it as "the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems." Those last words give the three levels that every textbook and every exam uses. genetic diversity is the variety of genes within one species, which is why one crop can exist in hundreds of local varieties and one animal in many breeds. Species diversity is the variety of different species in an area. Ecosystem diversity is the variety of habitats and communities, such as forests, grasslands, wetlands, deserts, mangroves and coral reefs. The three levels are nested: many ecosystems, each with many species, each species carrying many forms of its genes.

జన్యు వైవిధ్యం మార్పును తట్టుకునే సామర్థ్యం ఇస్తుంది. ఒకే రకం పంట వేస్తే ఒక్క తెగులు వచ్చినా మొత్తం పోతుంది; 1840లలో ఐర్లాండ్‌లో కొన్ని రకాల బంగాళాదుంపలపైనే ఆధారపడితే తెగులుతో పంట అంతా నాశనమై కరువుకు దారి తీసింది. అందుకే మన పాత దేశవాళీ విత్తనాలు విలువైనవి. చిత్తడి నేలలు వరద నీటిని పట్టుకుంటాయి, మడ అడవులు తీరాన్ని కాపాడతాయి. (→ English: genetic diversity · हिन्दी: आनुवंशिक विविधता)

In exam EnglishEach level matters for its own reason. Genetic variety is the raw material for adapting to change: a population whose members differ can survive a new disease or a hotter climate because some individuals happen to cope. Its loss can be costly. In Ireland in the 1840s, most of the poor depended on potatoes of very few varieties, and when a blight arrived almost the whole crop failed together, contributing to a famine. For the same reason plant breeders value the wild relatives of crops and old farmers' varieties, which carry genes for resistance and hardiness. India is one of the regions where crops such as rice, many pulses, mango and citrus have long been grown and varied, so its traditional varieties are a genetic treasury. Ecosystem diversity matters because each kind of ecosystem supplies its own services: wetlands store floodwater, mangroves shield coasts, forests protect catchments.

వైవిధ్యాన్ని లెక్కించడం: ఒక చోట ఎన్ని జాతులు అనేది జాతుల సంపన్నత. ఒకే చెట్టు జాతి అడవంతా ఉంటే వైవిధ్యం తక్కువ, అందుకే సమానత కూడా చూస్తారు. ఆల్ఫా: ఒక్క తోటలోని వైవిధ్యం. బీటా: ఒక తోట నుంచి పక్క తోటకి వెళ్తే ఎంత మారుతుంది, కొండ ఎక్కుతుంటే చెట్లు మారినట్టు. గామా: మొత్తం ప్రాంతం అంతా కలిపి. (→ English: species richness; alpha, beta and gamma diversity · हिन्दी: प्रजाति समृद्धि; अल्फ़ा, बीटा और गामा विविधता)

In exam EnglishCounting diversity is harder than it sounds. The simplest measure is species richness, the number of species in a place. But two forests with twenty species each are not equally diverse if in one forest a single species makes up almost every tree; so ecologists also look at evenness, how equally individuals are shared among species. The American ecologist Robert Whittaker separated diversity by scale. Alpha diversity is the diversity within one habitat or community, such as one patch of forest. Beta diversity is the change in species from one habitat to another, for example as one climbs a mountain or moves from a dry to a wet slope; high beta diversity means neighbouring communities share few species. Gamma diversity is the total diversity of a whole landscape or region, combining the first two. A region like the Western Ghats scores high on all three: rich individual forests, sharp changes over short distances, and a very large overall total.

భూమి మీద జీవం సమానంగా లేదు. భూమధ్యరేఖ దగ్గర ఉష్ణ మండలంలో జాతులు ఎక్కువ, ధ్రువాల వైపు వెళ్ళేకొద్దీ తగ్గుతాయి. కారణాలు: అక్కడ చాలా కాలం నుంచి వాతావరణం స్థిరంగా ఉంది, ఏడాదంతా పెద్ద మార్పు లేదు, ఎండ ఎక్కువ. రెండోది: ప్రాంతం పెద్దదైతే జాతులు ఎక్కువ, కానీ రెట్టింపు ప్రాంతానికి రెట్టింపు జాతులు రావు. అందుకే అడవిని ముక్కలు చేస్తే జాతులు పోతాయి. (→ English: latitudinal gradient; species–area relationship · हिन्दी: अक्षांशीय प्रवणता; प्रजाति-क्षेत्र संबंध)

In exam EnglishLife is not spread evenly over the planet. The clearest pattern is the latitudinal gradient: for most groups of plants and animals, the number of species is highest in the tropics and falls steadily towards the poles. A few hectares of Amazon or South-East Asian rainforest can hold more tree species than the whole of a temperate country. Several reasons are offered. The tropics have had a long and relatively stable history, so species have had more time to evolve; their climate varies less through the year, which favours specialists; and they receive more solar energy, which supports higher productivity and so more life. A second pattern links diversity to area. The naturalist Alexander von Humboldt noticed that larger areas hold more species, but not in proportion: richness rises quickly at first and then more slowly. Plotted on logarithmic scales the relationship becomes a straight line, which is why breaking a habitat into small pieces is expected to lose species.

ప్రపంచంలోని 17 మహావైవిధ్య దేశం జాబితాలో భారత్ ఒకటి. మన దగ్గర ప్రపంచ భూమిలో సుమారు 2.4 శాతమే ఉంది, కానీ నమోదైన జాతుల్లో 7 నుంచి 8 శాతం. ఎందుకంటే మన దేశంలో దీవులు, హిమాలయాలు, తడి ఈశాన్యం, ఎడారి అన్నీ ఉన్నాయి; మూడు వేర్వేరు జీవ ప్రాంతాల జీవులు ఇక్కడ కలుస్తాయి. మూడు రాష్ట్రాల సరిహద్దు ఊరిలో మూడు భాషలూ వినిపించినట్టు. (→ English: megadiverse country · हिन्दी: महाविविधता वाला देश)

In exam EnglishIndia is one of the world's 17 megadiverse country group, a list drawn up by Conservation International in 1998 of the countries that together hold most of the planet's species. Measured against its size, India is crowded with life: by the figures of the Ministry of Environment, Forest and Climate Change, its share of the planet's recorded species, some 7 to 8 per cent, is about three times its share of land, roughly 2.4 per cent. The reasons lie in its geography. India stretches from tropical islands to the high Himalaya and from the wet north-east to the Thar desert, so it contains almost every major type of ecosystem. It also sits where three great biological realms meet, the Indo-Malayan, the Palaearctic to the north and the Afro-tropical to the west, so its plants and animals have mixed origins. Long isolation of the Peninsula and of islands such as the Andaman and Nicobar group has added species found nowhere else. India is also a member of the Like-Minded Megadiverse Countries group formed in 2002 to coordinate positions in international talks on biodiversity.

సంరక్షణకు డబ్బు తక్కువ కాబట్టి ఎక్కడ కాపాడితే ఎక్కువ జాతులు బతుకుతాయో గుర్తించారు, అవే జీవవైవిధ్య హాట్ స్పాట్. రెండు షరతులు: ఎక్కడా లేని 1,500 మొక్కల జాతులు అక్కడ ఉండాలి, అసలు అడవిలో 70 శాతం ఇప్పటికే పోయి ఉండాలి. అంటే చాలా విలువైనది, చాలా ప్రమాదంలో ఉన్నది. ఇంట్లో మంటలు వస్తే ముందు అరుదైన, ఎక్కువ ప్రమాదంలో ఉన్న వస్తువును కాపాడినట్టు. ప్రపంచంలో 36 ఉన్నాయి. (→ English: biodiversity hotspot · हिन्दी: जैव विविधता हॉटस्पॉट)

In exam EnglishSince money and effort for conservation are limited, scientists have tried to identify the places where protection would save the most species. The British ecologist Norman Myers proposed the idea of biodiversity hotspots in 1988, and Conservation International later adopted it with two fixed tests. A region qualifies only if it holds at least 1,500 species of vascular plants found nowhere else in the world, and only if it has already lost at least 70 per cent of its original natural vegetation. The first test measures how irreplaceable the region is; the second measures how threatened it is. Both must be met, so a region that is very rich but still largely intact, such as much of the Amazon, is not a hotspot. There are now 36 hotspots. Together they cover only about 2.5 per cent of the Earth's land surface, yet more than half of the world's plant species are endemic to them, which is why they are seen as the best value for conservation effort.

భారతదేశంలో నాలుగు హాట్‌స్పాట్లు: హిమాలయాలు; ఈశాన్య రాష్ట్రాలు ఉన్న ఇండో-బర్మా; శ్రీలంకతో కలిసిన పశ్చిమ కనుమలు; నికోబార్ దీవులు ఉన్న సుండాలాండ్. తూర్పు కనుమలు, థార్ ఎడారి, సుందర్‌బన్స్ ముఖ్యమైనవే కానీ జీవవైవిధ్య హాట్ స్పాట్ జాబితాలో లేవు, ఇక్కడే చాలామంది పొరపడతారు. (→ English: biodiversity hotspot · हिन्दी: जैव विविधता हॉटस्पॉट)

In exam EnglishFour of the 36 hotspots reach into India, and the exam often asks which. The Himalaya hotspot covers the mountain arc from the north-west to the east, with steep changes in climate over short distances. The Indo-Burma hotspot takes in much of India's north-east and runs through Myanmar and South-East Asia; it is rich in orchids, bamboos, primates and freshwater fish. The Western Ghats and Sri Lanka hotspot is a single unit shared with the island across the Palk Strait; the Ghats run parallel to the west coast and stand out for their many endemic amphibians, reptiles and flowering plants. The Sundaland hotspot centres on Malaysia and western Indonesia, and India's share is the Nicobar Islands. A common error is to name the Eastern Ghats, the Thar or the Sundarbans as hotspots: they are important ecosystems but none of them is on the list.
India's four biodiversity hotspots
HotspotIndia's partShared with
HimalayaThe Himalayan arc, north-west to eastNepal, Bhutan and neighbours
Indo-BurmaMuch of the north-eastMyanmar and South-East Asia
Western Ghats and Sri LankaWestern Ghats along the west coastSri Lanka
SundalandNicobar IslandsMalaysia and western Indonesia

భారతదేశాన్ని పది జీవ భౌగోళిక మండలం లుగా విభజించారు: ట్రాన్స్-హిమాలయ, హిమాలయ, ఎడారి, పాక్షిక శుష్క, పశ్చిమ కనుమలు, దక్కన్ ద్వీపకల్పం, గంగా మైదానం, ఈశాన్యం, తీరాలు, దీవులు. అన్నిటికంటే పెద్దది దక్కన్. ఎందుకంటే ప్రతి మండలంలోనూ కొంత భాగం కాపాడాలి; ఒక ఊరి పంచాయతీలో ప్రతి వీధికీ ఒక ప్రతినిధి ఉండాలి కదా, అలాగే. (→ English: biogeographic zone · हिन्दी: जैव-भौगोलिक क्षेत्र)

In exam EnglishTo plan protected areas sensibly, India also needed a map of its own natural regions. The Wildlife Institute of India, in a classification prepared by W. A. Rodgers and H. S. Panwar, divided the country into ten biogeographic zones, each with a distinct mix of climate, landform, plants and animals, and subdivided them further into provinces. The ten are the Trans-Himalaya, the Himalaya, the Indian Desert, the Semi-Arid zone, the Western Ghats, the Deccan Peninsula, the Gangetic Plain, the North-East, the Coasts and the Islands. The Deccan Peninsula is by far the largest. The point of the scheme is representation: a good network of protected areas should include samples of every zone, not just the scenic mountains or famous tiger forests, so that grasslands, deserts and coasts are protected too. The zones also help explain the hotspots, since the Himalaya, the Western Ghats, the North-East and the Islands are the zones richest in species found only there.
India's ten biogeographic zones (Wildlife Institute of India)
ZoneWhere
Trans-HimalayaCold desert of Ladakh and Lahaul–Spiti
HimalayaThe main mountain ranges
Indian DesertThar and Kachchh
Semi-AridPunjab plains to Gujarat and the drier Deccan edge
Western GhatsHills along the west coast
Deccan PeninsulaThe central and southern plateau; the largest zone
Gangetic PlainPlains of the Ganga and its tributaries
North-EastBrahmaputra valley and north-eastern hills
CoastsThe west and east coastal belts
IslandsAndaman and Nicobar, Lakshadweep

ఒకే ప్రాంతంలో మాత్రమే, ఇంకెక్కడా లేని జాతులు స్థానిక జాతులు. దీవులు, ఒంటరి కొండలు వీటికి నిలయం. పశ్చిమ కనుమల్లో నీలగిరి తార్, సింహపు తోక కోతి, ఊదా కప్ప; మణిపూర్‌లో సంగాయ్ జింక; గిర్‌లో ఆసియా సింహం. ఊరిలో ఒక్క ఇంట్లోనే ఉన్న పాత వంటకం లాంటిది: ఆ ఇల్లు పోతే ఆ వంటకం ప్రపంచంలోనే పోతుంది. (→ English: endemic species · हिन्दी: स्थानिक प्रजाति)

In exam EnglishAn endemic species is one that occurs naturally in a single area and nowhere else; endemism is the share of a region's species that are endemic. Isolation breeds endemics, which is why islands, isolated mountain ranges and old, stable landscapes have many. India's main centres of endemism are the Western Ghats, the north-east, the Himalaya and the Andaman and Nicobar Islands. Examples that the exam likes include the Nilgiri tahr and the lion-tailed macaque of the Western Ghats, the purple frog that spends most of its life underground in the same hills, the Sangai or brow-antlered deer of Manipur's Keibul Lamjao, and the Narcondam hornbill confined to a single small island in the Andaman Sea. The Asiatic lion now survives in the wild only in the Gir landscape of Gujarat. Endemic species carry a special risk: if their small home is damaged there is no other population to fall back on, so a local loss becomes a global extinction.

మొత్తం భాగం ఒక గొలుసు: జీవవైవిధ్యం మూడు స్థాయిల్లో ఉంటుంది, దాన్ని లెక్కిస్తారు, ఉష్ణ ప్రాంతాల్లో, పెద్ద ఒంటరి ప్రాంతాల్లో ఎక్కువ. అందుకే భారత్ సంపన్నం. హాట్‌స్పాట్లు విలువైనవి, ప్రమాదంలో ఉన్నవి; మండలాలు ప్రతి రకమైన ప్రకృతినీ కాపాడేలా చూస్తాయి; స్థానిక జాతులు చిన్న చోటు పోతే జాతే పోతుందని గుర్తు చేస్తాయి. తర్వాతి భాగం: ఎందుకు నశిస్తోంది, ఎలా కాపాడుతున్నాం. (→ English: biodiversity · हिन्दी: जैव विविधता)

In exam EnglishThe ideas in this part fit together as a chain. Biodiversity exists at three nested levels, genes, species and ecosystems, and each level gives life a different kind of insurance. It is measured by richness and evenness and compared within habitats, between them and across regions. It is concentrated in the tropics and in large, varied, isolated areas, which is why India, with its range of climates and its meeting of biological realms, ranks among the megadiverse countries. Hotspots single out regions that are both irreplaceable and badly damaged, and India shares four of them; the ten biogeographic zones make sure that conservation covers every kind of Indian landscape, and endemic species show why losing a small area can mean losing a species for ever. With this map of where life is, Part 2 asks why it is being lost and what is being done to save it.

Exam traps

Recap

Practice questions

Q1. The existence of many traditional varieties of rice in India is an example of

  1. species diversity
  2. genetic diversity
  3. ecosystem diversity
  4. gamma diversity
Show answer

Answer: B. genetic diversity

All rice varieties belong to one species, so their variety is genetic diversity. Species diversity needs different species, ecosystem diversity needs different habitats, and gamma diversity is the total diversity of a region, not variation within a crop.

Q2. The change in species composition as one moves from one habitat to another along an environmental gradient is called

  1. alpha diversity
  2. beta diversity
  3. gamma diversity
  4. species evenness
Show answer

Answer: B. beta diversity

Beta diversity measures turnover between habitats. Alpha is diversity within one habitat, gamma is the total for a region, and evenness describes how equally individuals are spread among species.

Q3. Consider the following statements:
1. A region must have lost at least 70 per cent of its original natural vegetation to qualify as a biodiversity hotspot.
2. Any region with very high species richness qualifies as a hotspot even if its habitat is largely intact.
Which of the statements given above is/are correct?

  1. 1 only
  2. 2 only
  3. Both 1 and 2
  4. Neither 1 nor 2
Show answer

Answer: A. 1 only

Statement 1 is one of the two required tests. Statement 2 is wrong because the threat test must also be met; a rich but intact region is not a hotspot. So '2 only', 'both' and 'neither' are wrong.

Q4. Which one of the following is NOT a biodiversity hotspot that includes any part of India?

  1. Indo-Burma
  2. Sundaland
  3. Eastern Ghats
  4. Himalaya
Show answer

Answer: C. Eastern Ghats

The Eastern Ghats are not a hotspot. Indo-Burma includes much of the north-east, Sundaland includes the Nicobar Islands, and the Himalaya hotspot covers the Indian Himalaya, so those three options all include India.

Q5. Consider the following statements:
1. India is one of the 17 megadiverse countries.
2. India has about 2.4 per cent of the world's land area.
3. India accounts for about a quarter of the world's recorded species.
Which of the statements given above is/are correct?

  1. 1 and 2 only
  2. 2 and 3 only
  3. 1 and 3 only
  4. 1, 2 and 3
Show answer

Answer: A. 1 and 2 only

Statements 1 and 2 are correct. Statement 3 is wrong: India's share is about 7 to 8 per cent, not a quarter. So every option containing statement 3 is wrong.

Q6. Which is the largest of India's ten biogeographic zones?

  1. Western Ghats
  2. Gangetic Plain
  3. Deccan Peninsula
  4. Himalaya
Show answer

Answer: C. Deccan Peninsula

The Deccan Peninsula covers the vast central and southern plateau and is the largest zone. The Western Ghats are a narrow hill belt, and the Gangetic Plain and the Himalaya, though large, are smaller than the Deccan.

Q7. Match the endemic species with their regions:
A. Sangai (brow-antlered deer) 1. Western Ghats
B. Lion-tailed macaque 2. Andaman Sea island
C. Narcondam hornbill 3. Gujarat
D. Asiatic lion 4. Manipur
Select the correct answer using the code given below:

  1. A-4, B-1, C-2, D-3
  2. A-1, B-4, C-2, D-3
  3. A-4, B-1, C-3, D-2
  4. A-2, B-1, C-4, D-3
Show answer

Answer: A. A-4, B-1, C-2, D-3

The Sangai lives in Manipur's Keibul Lamjao, the lion-tailed macaque in the Western Ghats, the Narcondam hornbill on Narcondam island and the wild Asiatic lion in Gir, Gujarat. The second code swaps the deer and the macaque, the third swaps the hornbill and the lion, and the fourth swaps the deer and the hornbill.

Q8. Which one of the following best explains why species richness is generally highest in the tropics?

  1. Tropical regions have the largest human populations
  2. A long, relatively stable history, less seasonal climate and more solar energy
  3. Tropical soils are always the most fertile in the world
  4. The tropics were repeatedly covered by ice sheets
Show answer

Answer: B. A long, relatively stable history, less seasonal climate and more solar energy

The usual explanations are a long stable history, a less seasonal climate and more solar energy. Human numbers do not create species richness, many tropical rainforest soils are in fact poor, and ice sheets covered high latitudes, not the tropics, which is one reason the tropics had longer undisturbed time.

All partsNext: Part 2 →

Study this in the Upscore app to keep notes, save it for revision, track your practice scores and follow a plan to the exam date. It's free.

Study this in the app →

Sources