Sustainable Management of Natural Resources

Why this chapter matters for UPSC: This was Chapter 16 of NCERT's Class X Science in the 2020-21 edition (pp. 266-280). It is not in the current book: Reprint 2026-27 has 13 chapters, and this one was dropped in NCERT's 2022 rationalisation. It is still one of the most useful short texts for GS1 resource geography and GS3 environment, because it frames resource questions the way Mains asks them: who has a stake in a forest, why large dams draw criticism, why a check dam is built to fill the ground rather than a pond, and why coal and petroleum must be used carefully even before they run out. The chapter's cases (Chipko, Arabari, the Bishnois, the kulhs of Himachal Pradesh, Rajendra Singh's johads) are standard examples in answers on participation and local control.

Contemporary hook: Groundwater is where the chapter's argument is tested today. The Central Ground Water Board's 2025 national assessment puts India's annual groundwater extraction at 247.22 billion cubic metres, 60.63% of the extractable resource, and classifies 730 of 6,762 assessment units as over-exploited (CGWB, November 2025). On 10 March 2026 the Union Cabinet extended the Jal Jeevan Mission up to December 2028; on that date 15.80 crore of 19.36 crore rural households (81.61%) were reported to have tap water connections.

🧠 First Principles — Read This First

1. Everything we use comes from the earth's resources; only energy comes from outside. NCERT lists food, clothes, books, toys, furniture, tools and vehicles, and notes that even the Sun's energy is processed by living organisms and physical and chemical processes before we use it (p. 269).
2. Resources are limited while demand keeps rising. With population rising "at a tremendous rate due to improvement in health-care", demand for all resources is "increasing at an exponential rate" (p. 269). So management needs a long-term perspective, equitable distribution, and a plan for the wastes that extraction creates (pp. 269-270).
3. The five R's are a ladder, not a list. Refuse, Reduce, Reuse, Repurpose, Recycle. NCERT ranks reuse above recycling because recycling itself uses energy (p. 268).
4. A forest has four stakeholders with different needs. Local people, the Forest Department, industrialists, and wildlife and nature enthusiasts (p. 271). Most of the chapter's forest argument follows from asking which of them depends on one particular forest.
5. Local control is the chapter's recurring lesson. Chipko, Arabari, the kulhs and the johads all show that when people control a local resource, it is used and maintained better (pp. 274-277).
6. Water stored underground beats water stored in the open. It does not evaporate, it spreads to recharge wells, it does not breed mosquitoes, and it is relatively protected from contamination (pp. 277-278).
7. Coal and petroleum are exhaustible and polluting. They were formed from bio-mass millions of years ago, will be exhausted however carefully we use them, and burning them releases poisonous gases and carbon dioxide (pp. 278-279).

PART 1 — Quick Reference

Table 1: The five R's (introduction)

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, introduction (pp. 268-269).

Table 2: Why we need to manage resources (16.1)

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, introduction and section 16.1 (pp. 269-270).

Table 3: Tradition and conservation in the chapter

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, introduction and section 16.1 (pp. 266, 270-271).

Table 4: The four stakeholders of a forest (16.2.1)

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, sections 16.2.1 (pp. 271-273).

Table 5: People and forests, the chapter's cases (16.2)

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, sections 16.2.1-16.2.2 and box (pp. 273-275).

Table 6: Large dams, the case for and against (16.3.1)

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, sections 16.3-16.3.1 (pp. 275-277).

Table 7: Traditional water harvesting structures named by NCERT (16.3.2)

NCERT calls these ancient water harvesting, "including water conveyance", structures still in use today, and its Fig. 16.4 shows "an ideal setting of the khadin system".

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, section 16.3.2, box and Fig. 16.4 (pp. 277-278).

Table 8: Kulhs, check dams and groundwater (16.3.1 box, 16.3.2)

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, sections 16.3.1-16.3.2 (pp. 276-278).

Table 9: Coal and petroleum (16.4)

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, section 16.4 (pp. 278-279).

Table 10: Activities in the chapter

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, Activities 16.1-16.12 (pp. 266-279).

Table 11: Questions and exercises, with answers drawn from the chapter

The 2020-21 book's Answers pages end with Chapter 15, so Chapter 16 has no printed key. Most of these questions are open-ended; the answers below show what the chapter's own text supports.

Source: NCERT, Science Class X, 2020-21 edition, ch. 16, Questions (pp. 271, 275, 278) and Exercises (p. 280); the Answers pages of that edition (pp. 281-282) end with Chapter 15.

Table 12: NCERT lines to read with care

Source: NCERT, Science Class X, 2020-21 edition, ch. 16 (pp. 266-279); NCERT, Biology Class XII, Reprint 2025-26, ch. 13 (p. 224); NCERT, India: Physical Environment, Class XI, Reprint 2026-27, ch. 3 (p. 21); Rajasthan Foundation, "Aapno Sanskriti"; MoEF notice, Amrita Devi Bishnoi Wildlife Protection Award, 2007; THDC India Limited, Tehri Dam; NMCG, Namami Gange Programme; Uttarakhand Biodiversity Board, Chipko Movement; IGNOU, Block 3; PIB, 9 December 2019 (PRID 1595507) and 7 October 2019 (PRID 1587407).

PART 2 — Concepts & Narrative

Why the chapter opens with tradition (introduction)

The chapter begins with a claim about culture before it says anything about science: "'Living in harmony with nature' is not new to us." NCERT says sustainable living has been part of India's traditions, customs, art and crafts, festivals, food, beliefs, rituals and folklore, and points to the Sanskrit phrase 'Vasudhaiv kutumbakam', "the entire earth is one family" (p. 266). It then links the chapter to what came before: Class IX introduced soil, air and water and how components are cycled in nature, and the previous chapter dealt with their pollution. This chapter turns to forests, wildlife, water, coal and petroleum, and to "the issues at stake in deciding how these resources are to be managed for sustainable development along with the input from our traditional practices" (p. 266).

The opening also answers a feeling many readers have: environmental problems seem global and we feel helpless. NCERT notes that there are international laws and regulations, national laws and acts, and national and international organisations working to protect the environment (p. 266), and Activities 16.1 and 16.2 send the reader to find them. Its second answer is personal. "We need not feel powerless or overwhelmed by the scale of the problems because there are many things we can do to make a difference" (p. 268), and those things are the five R's.

Awareness, NCERT says, has been "a fairly recent phenomenon in our society", and action usually follows awareness. Its example is the Ganga Action Plan, a "multi-crore project" that "came about in 1985 because the quality of the water in the Ganga was very poor" (p. 267). The page carries a graph of total coliform levels along the river (Fig. 16.1, CPCB data for 2012), and the chapter defines the term.

Activity 16.3 shows how a pollution question can be partly answered at home. Some pollutants are harmful even in very small quantities and need sophisticated equipment to measure, but "the pH of water is something that can easily be checked using universal indicator" (p. 268), as the reader learnt in Chapter 2.

The five R's (introduction)

NCERT gives the five R's as "Refuse, Reduce, Reuse, Repurpose and Recycle" (p. 268). The order matters. Refusing and reducing stop a resource being used at all. Reusing keeps an object in use without any processing, and NCERT says this "is actually even better than recycling because the process of recycling uses some energy" (p. 268). Repurposing gives a worn-out object a second job. Recycling comes last because it needs collection, segregation and energy, but it still beats "synthesising or extracting fresh plastic, paper, glass or metal" (p. 269).

The chapter's summary repeats the maxim and explains its purpose: "We can reduce pressure on the environment by sincerely applying the maxim of 'Refuse, Reduce, Reuse, Repurpose and Recycle' in our lives" (p. 280).

Why do we need to manage our resources? (16.1)

Section 16.1 makes four arguments in quick succession. First, everything we use, "food, clothes, books, toys, furniture, tools and vehicles", comes from resources on this earth; the only thing from outside is energy from the Sun (p. 269). Second, these resources "are not unlimited", while demand rises at an exponential rate as population grows. Third, management needs a long-term perspective "so that these will last for the generations to come and will not merely be exploited to the hilt for short-term gains" (pp. 269-270). Fourth, management "should also ensure equitable distribution of resources so that all, and not just a handful of rich and powerful people, benefit from the development of these resources" (p. 270).

A fifth point is easy to miss: the damage done while a resource is extracted or used. Mining "causes pollution because of the large amount of slag which is discarded for every tonne of metal extracted", so sustainable management "demands that we plan for the safe disposal of these wastes too" (p. 270).

The section ends with tradition again. NCERT says present-day global concern for sustainable development is "of recent origin as compared to the long tradition and culture of nature conservation in our country" (p. 270), and its box quotes two hymns of the Atharva Veda in Devi Chand's 1997 translation. The second carries the principle of regeneration: "Whatever I dig out of you, O Earth! May that have quick regeneration again; may we not damage thy vital habitat and heart" (p. 270). In the Vedic period "both productive as well as protective aspect of forest vegetation were emphasised", and in the later Vedic period, as agriculture became dominant, the cultural landscape of "sacred forests and groves, sacred corridors and a variety of ethno-forestry practices" evolved (pp. 270-271).

Forests and wildlife (16.2)

NCERT opens the forest section with biodiversity. One measure of an area's biodiversity is the number of species found there, but "the range of different life forms (bacteria, fungi, ferns, flowering plants, nematodes, insects, birds, reptiles and so on) found, is also important" (p. 271). One of the main aims of conservation is to preserve the biodiversity we have inherited, because "Experiments and field studies suggest that loss of diversity may lead to loss of ecological stability" (p. 271).

The section's first line calls forests "'biodiversity hotspots'". In UPSC usage the term has a narrower technical meaning, set out in Class XII Biology and in Table 12 above; for Class X, read it simply as a way of saying that forests are very rich in biodiversity.

Stakeholders (16.2.1)

NCERT's key move is to ask who depends on a forest, and how much. "We all use various forest produce. But our dependency on forest resources varies. Some of us have access to alternatives, some do not" (p. 271). It names four stakeholders.

Local people. They need "large quantities of firewood, small timber and thatch". Bamboo makes hut slats and baskets for collecting and storing food; implements for agriculture, fishing and hunting are largely made of wood; forests are themselves sites for fishing and hunting; people gather fruits, nuts and medicines; cattle graze in the forest or eat fodder collected from it (p. 272). NCERT asks whether such use would exhaust the forest, and answers with history: "before the British came and took over most of our forest areas, people had been living in these forests for centuries. They had developed practices to ensure that the resources were used in a sustainable manner" (p. 272). After the British took control, which NCERT says they "exploited ruthlessly for their own purposes", these people were forced to depend on much smaller areas, and resources "started becoming over-exploited to some extent" (p. 272).

The Forest Department. In independent India it "took over from the British but local knowledge and local needs continued to be ignored in the management practices" (p. 272). Vast tracts became "monocultures of pine, teak or eucalyptus". Huge areas are first cleared of all vegetation, which "destroys a large amount of biodiversity", and the plantations cannot meet the varied needs of local people for "leaves for fodder, herbs for medicines, fruits and nuts for food". They serve industry and are "an important source of revenue for the Forest Department" (p. 272).

Industrialists. A short count of forest-based industries "reveals timber, paper, lac and sports equipment" (p. 272). Industry treats the forest "as merely a source of raw material for its factories", and "huge interest-groups lobby the government for access to these raw materials at artificially low rates" (p. 272). Because industries have a greater reach than local people, they have no stake in one forest: "after cutting down all the teak trees in one area, they will get their teak from a forest farther away" (p. 272).

Nature and wildlife enthusiasts. They are "in no way dependent on the forests, but ... may have considerable say in their management" (p. 273). Conservationists "were initially taken up with large animals like lions, tigers, elephants and rhinoceros. They now recognise the need to preserve biodiversity as a whole" (p. 273).

NCERT then asks: "shouldn't we recognise people as forming part of the forest system?" (p. 273). Its examples are the Bishnois and the Great Himalayan National Park. The Bishnois live in western Rajasthan on the border of the Thar desert; for them "Conservation of forest and wildlife has been a religious tenet", and they live by the philosophy "that all living things have a right to survive and share all resources" (p. 273). In the Great Himalayan National Park, alpine meadows were grazed by sheep every summer until the park was formed and the practice ended; "Now it is seen that without the regular grazing by sheep the grass first grows very tall, and then falls over preventing fresh growth" (p. 273). NCERT's conclusion: "the prejudice against the traditional use of forest areas has no basis" (p. 273).

It does not let anyone off lightly. "Management of protected areas by keeping the local people out or by using force cannot possibly be successful in the long run", and damage to forests cannot be attributed to local people only, when there is "deforestation caused by industrial needs or development projects like building roads or dams", and damage by tourists and the arrangements made for them (p. 273). The aim is use that is "both environmentally and developmentally sound", in which "the benefits of the controlled exploitation go to the local people, a process in which decentralised economic growth and ecological conservation go hand in hand" (p. 273). The section closes with a line worth quoting in Mains: "The environment must not be regarded as a pristine collection of plants and animals. It is a vast and complex entity that offers a range of natural resources for our use" (p. 273).

Management of forest: Chipko and Arabari (16.2.2)

The stakeholders' goals are not the same, and NCERT names the conflict directly: "Forest resources are often made available for industrial use at rates far below the market value while these are denied to the local people" (p. 274).

Chipko. The Chipko Andolan ("'Hug the Trees Movement'") was, in NCERT's words, "the result of a grassroot level effort to end the alienation of people from their forests" (p. 274). NCERT traces it to "an incident in a remote village called Reni in Garhwal, high-up in the Himalayas during the early 1970s". A logging contractor had been allowed to fell trees near the village; his workers came while the men were absent; "Undeterred, the women of the village reached the forest quickly and clasped the tree trunks thus preventing the workers from felling the trees", and the contractor withdrew (p. 274).

NCERT's analysis is the part to remember. The dispute was about "the conservation of a replenishable resource", and specifically "the method of use". The contractor would have felled the trees for ever; "The communities traditionally lop the branches and pluck the leaves, allowing the resource to replenish over time" (p. 274). The movement "quickly spread across communities and media, and forced the government, to whom the forest belongs, to rethink their priorities in the use of forest produce" (p. 274). People had learnt that destroying forests affected "not just the availability of forest products, but also the quality of soil and the sources of water" (p. 274).

Arabari. NCERT's box "An Example of People's Participation in the Management of Forests" is precise and Prelims-friendly. In 1972 the West Bengal Forest Department recognised its failures in reviving degraded sal forests in the south-western districts of the state. Surveillance and policing had led to "'complete alienation of the people from the administration'", with frequent clashes, and forest and land conflicts were "a major factor in fuelling the militant peasant movements led by the Naxalites" (p. 274). The Department changed strategy in the Arabari forest range of Midnapore district, where, "at the insistence of a far-seeing forest officer, A.K. Banerjee", villagers were involved in protecting "1,272 hectares of badly degraded sal forest" (p. 274). In return they got "employment in both silviculture and harvesting operations, 25 per cent of the final harvest", and fuelwood and fodder collection "on payment of a nominal fee". The result: "by 1983, a previously worthless forest was valued Rs 12.5 crores" (p. 275).

Activity 16.8 tests the argument against the chapter's own list of damage: rest houses for tourists, grazing of domestic animals, and tourists' litter in national parks (p. 275). Grazing is the interesting case, because the Great Himalayan National Park example shows that some grazing helps.

Water for all (16.3)

"Water is a basic necessity for all terrestrial forms of life" (p. 275). Human intervention pollutes waterbodies, as Class IX showed, but it "also changes the availability of water in various regions" (p. 275). Activity 16.9 makes the point sharply: villages with chronic water shortage surround a water theme park in Maharashtra.

Activity 16.10 asks the reader to map rainfall and water scarcity, and then asks whether it would be surprising "that regions of water scarcity are closely correlated to the regions of acute poverty" (p. 275). Rainfall alone does not explain scarcity. Rains in India come largely from the monsoons, so "most of the rain falls in a few months of the year" (p. 275). And despite the monsoon, "failure to sustain water availability underground has resulted largely from the loss of vegetation cover, diversion for high water demanding crops, and pollution from industrial effluents and urban wastes" (p. 275).

Dams, tanks and canals are old in India. NCERT says they "have been used in various parts of India since ancient times", were "generally local interventions managed by local people", and assured that basic needs for agriculture and daily use were met throughout the year (p. 275). Use of stored water was strictly regulated, cropping patterns were set by "decades/centuries of experience", and maintenance "was also a local affair" (p. 276).

Dams (16.3.1)

Large dams store "adequate water not just for irrigation, but also for generating electricity", and canals carry it over great distances; "the Indira Gandhi Canal has brought greenery to considerable areas of Rajasthan" (p. 276). The trouble is distribution. "There is no equitable distribution of water, thus people close to the source grow water intensive crops like sugarcane and rice while people farther downstream do not get any water" (p. 276). Their grievance adds to that of people displaced by the dam and its canals.

NCERT names three criticisms of large dams (pp. 276-277):

1. Social: they "displace large number of peasants and tribals without adequate compensation or rehabilitation";
2. Economic: they "swallow up huge amounts of public money without the generation of proportionate benefits";
3. Environmental: they "contribute enormously to deforestation and the loss of biological diversity".

The displaced are "largely poor tribals who do not get any benefits from these projects", and "The oustees of the Tawa Dam built in the 1970s are still fighting for the benefits they were promised" (p. 277). The chapter mentions the Tehri Dam and the Narmada Bachao Andolan's protest against raising the height of the Sardar Sarovar Dam on the Narmada (p. 276).

NCERT also gives the history. Large dams and long canals were "first conceived and implemented by the British and carried on with no less gusto by our newly formed independent government" (p. 276). These mega-projects led to the neglect of local irrigation methods, and the government took over the administration of local systems, "leading to the loss of control over the local water sources by the local people" (p. 276).

Water harvesting (16.3.2)

NCERT defines watershed management with care: it "emphasises scientific soil and water conservation in order to increase the biomass production. The aim is to develop primary resources of land and water, to produce secondary resources of plants and animals for use in a manner which will not cause ecological imbalance" (p. 277). It "not only increases the production and income of the watershed community, but also mitigates droughts and floods and increases the life of the downstream dam and reservoirs" (p. 277).

Organisations have worked on "rejuvenating ancient systems of water harvesting as an alternative to the 'mega-projects' like dams". Communities have "dug small pits and lakes, put in place simple watershed systems, built small earthen dams, constructed dykes, sand and limestone reservoirs, set up rooftop water-collecting units", and this "has recharged groundwater levels and even brought rivers back to life" (p. 277).

"Water harvesting is an age-old concept in India" (p. 277). NCERT's list of structures is in Table 7. Two lines carry the chapter's argument: water harvesting techniques "are highly locale specific and the benefits are also localised", and "Giving people control over their local water resources ensures that mismanagement and over-exploitation of these resources is reduced/removed" (p. 277).

On level ground, the structures are "crescent shaped earthen embankments or low, straight concrete-and-rubble 'check dams' built across seasonally flooded gullies". Monsoon rains fill ponds behind them, but "Only the largest structures hold water year round; most dry up six months or less after the monsoons. Their main purpose, however, is not to hold surface water but to recharge the ground water beneath" (p. 277).

The chapter's box on Rajendra Singh gives a human face to all this. NCERT calls him India's "waterman" and quotes that in "two decades of efforts of Dr. Rajendra Singh, 8,600 johads and other structures to collect water have been built in Rajasthan," and "Water had been brought back to a 1,000 villages across the state." It adds: "In 2015, he won the Stockholm Water Prize" (p. 277). The beyond-the-textbook box below gives SIWI's own record of the prize.

Coal and petroleum (16.4)

Forests, wildlife and water "can meet our needs perpetually if we were to use them in a sustainable manner" (p. 278). Coal and petroleum are different. "Since the industrial revolution", energy needs have been "largely met by the reserves of coal and petroleum" (p. 278). Because "Coal and petroleum were formed from the degradation of bio-mass millions of years ago", they are "resources that will be exhausted in the future no matter how carefully we use them" (p. 278). NCERT quotes estimates that known petroleum resources "will last us for about forty years and the coal resources will last for another two hundred years" (p. 279), while noting that "Various estimates exist"; the book gives no base year for them.

Exhaustion is not the only reason for care. Because coal and petroleum come from bio-mass, "in addition to carbon, these contain hydrogen, nitrogen and sulphur" (p. 279).

Activity 16.11 turns the section into everyday choices: a bus, a personal vehicle, or walking and cycling; LED bulbs or fluorescent tubes; the lift or the stairs; an extra sweater or a heater or 'sigri' (p. 279). NCERT also points to machines: fuel is most used in internal combustion engines for transport, and "recent research in this field concentrates on ensuring complete combustion in these engines in order to increase efficiency and also reduce air pollution" (p. 279). Activity 16.12 asks about the Euro I and Euro II emission norms; India's own standards today are the Bharat Stage norms (Table 12).

An overview of natural resource management (16.5)

The closing section is short and candid. "Sustainable management of natural resources is a difficult task", and it needs an open mind about the interests of various stakeholders (p. 280). NCERT accepts "that people will act with their own best interests as the priority", but says the realisation that selfish goals will lead to misery for many and "a total destruction of our environment is slowly growing". Its last sentence is the chapter's thesis: "Going beyond laws, rules and regulations, we need to tailor our requirements, individually and collectively, so that the benefits of development reach everyone now and for all generations to come" (p. 280).

The summary compresses the chapter into five lines: resources need sustainable use; the five R's reduce pressure on the environment; forest management must take all stakeholders into account; dams have social, economic and environmental implications and "Alternatives to large dams exist. These are locale-specific and may be developed so as to give local people control over their local resources"; and coal and petroleum "will ultimately be exhausted", so, because their combustion also pollutes, they must be used judiciously (p. 280).

What happened to this chapter?

This chapter was printed as Chapter 16 (pp. 266-280) in the 2020-21 edition of NCERT's Class X Science. It is absent from the current book: Reprint 2026-27 lists 13 chapters, and its imprint records a "Revised Edition October 2022". It was dropped in NCERT's 2022 rationalisation of textbooks; the front matter explains the rationalisation in general terms and gives no reason chapter by chapter.

Two threads survive in the current book. The pH test that Activity 16.3 relies on is still taught in Chapter 2, Acids, Bases and Salts, and Chapter 4 keeps the box "Formation of coal and petroleum" (p. 70) with the bio-mass origin that section 16.4 builds on. The chapter's forests, dams and water-harvesting material is not carried forward anywhere in the current Class X book.

Source: NCERT, Science Class X, 2020-21 edition (whole-book zip, Wayback Machine capture of 9 October 2021); NCERT, Science Class X, Reprint 2026-27, front matter (Contents and imprint) and ch. 4 (p. 70).

PART 3 — UPSC Integration

Frames for Mains Answers

1. Who should manage a forest? Open with NCERT's four stakeholders and the test of dependence. Show the failure of exclusion (British control, monocultures of pine, teak or eucalyptus, industry lobbying for raw material at artificially low rates). Use Chipko for why people resist, Arabari (1972, 1,272 ha, 25 per cent of the harvest, Rs 12.5 crores by 1983) for how partnership works, and the Great Himalayan National Park for why traditional use is not automatically harmful. Close with NCERT's "environmentally and developmentally sound" principle and the 2023 amendment of forest law as the current legal frame.

2. Large dams or local harvesting? State the case for dams (irrigation, power, the Indira Gandhi Canal), then NCERT's three criticisms (social, economic, environmental) and the equity problem upstream and downstream. Contrast with locale-specific systems (kulhs, khadins, johads, check dams) that recharge groundwater. Bring in CGWB 2025 (60.63% stage of extraction; 730 over-exploited units) to show why recharge matters. Conclude that the two are complements: watershed work "increases the life of the downstream dam and reservoirs".

3. Sustainable development as equity. Define it with Brundtland, then add NCERT's equity within the present generation ("all, and not just a handful of rich and powerful people"). Use the five R's for individual action, slag disposal for the hidden cost of extraction, and the closing line of 16.5 ("the benefits of development reach everyone now and for all generations to come") as the conclusion. This frame fits the 2020 GS3 question on intra- and inter-generational equity.

4. Fossil fuels: exhaustible and polluting. Two separate reasons for care: they will run out, and burning them releases poisonous gases and carbon dioxide. Add the efficiency route (complete combustion), BS-VI from 1 April 2020, E20, and the difference between India's COP26 announcement (500 GW) and its NDC commitments (about 50% non-fossil capacity by 2030; 60% by 2035).

Exam Strategy

Prelims fact-traps:

• NCERT has five R's, not three: Refuse, Reduce, Reuse, Repurpose, Recycle. Reuse is ranked above recycling because recycling uses energy.
• Arabari is in Midnapore district, West Bengal; the forest was sal; villagers got 25 per cent of the final harvest; the area was 1,272 hectares; the officer was A.K. Banerjee.
• NCERT's Chipko village is Reni in Garhwal; the landmark Reni event is dated 26 March 1974 by the Uttarakhand Biodiversity Board (Reni is in Chamoli district).
• Tehri stands on the Bhagirathi, not on the Ganga proper (THDC).
• Match structures to states: kulhs (Himachal Pradesh), bandharas and tals (Maharashtra), bundhis (MP and UP), ahars and pynes (Bihar), eris (Tamil Nadu), surangams (Kerala), kattas (Karnataka), khadins and nadis (Rajasthan), ponds of the Kandi belt (Jammu).
• In a kulh, the farthest village takes water first.
• Check dams are built mainly to recharge groundwater, not to hold surface water; most dry up within six months of the monsoon.
• Burning in insufficient air gives carbon monoxide; NCERT calls oxides of sulphur and nitrogen and carbon monoxide poisonous at high concentrations and carbon dioxide a greenhouse gas.
• India went from BS-IV to BS-VI (from 1 April 2020); Euro I and II in the NCERT activity are historical.
• 500 GW by 2030 is the COP26 announcement; the NDC targets are about 50% non-fossil capacity by 2030 and 60% by 2035.

Mains:

• The chapter's cases are compact and verifiable. One line each on Chipko, Arabari, kulhs and Rajendra Singh will support most answers on participation.
• Use NCERT's three criticisms of large dams as a ready structure, then balance them with the benefits.
• For groundwater, quote CGWB 2025 figures with the year; they change with every assessment.
• Keep the equity argument in both dimensions: across generations (Brundtland) and within the present one (NCERT 16.1).

Practice Questions

Chapter 16's exercises have no multiple-choice questions, so every question below is Practice (UPSC-pattern, not past papers).

1. According to NCERT, which of the five R's is "even better than recycling", and why?
(a) Refuse, because it avoids buying harmful products
(b) Reduce, because it saves electricity and water
(c) Reuse, because the process of recycling uses some energy
(d) Repurpose, because it finds a new use for broken things

Answer: (c). NCERT ranks reuse above recycling because recycling itself uses energy (NCERT 2020-21, p. 268).

2. Consider the following statements about the Arabari experiment:
1. It began in the Midnapore district of West Bengal.
2. Villagers were given 25 per cent of the final harvest.
3. It covered 1,272 hectares of degraded teak forest.
Which of the statements given above is/are correct?
(a) 1 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3

Answer: (b). The forest was sal, not teak (NCERT 2020-21, p. 274).

3. Which one of the following pairs of traditional water harvesting structure and state is not correctly matched as per NCERT?
(a) Kulhs : Himachal Pradesh
(b) Surangams : Kerala
(c) Bandharas : Bihar
(d) Eris : Tamil Nadu

Answer: (c). Bandharas and tals are listed for Maharashtra; Bihar's structures are ahars and pynes (NCERT 2020-21, p. 277).

4. The Tehri Dam is built across which river?
(a) Alaknanda
(b) Bhagirathi
(c) Mandakini
(d) Yamuna

Answer: (b). THDC describes it as an earth and rockfill dam across the River Bhagirathi.

5. NCERT describes which of the following products of burning coal and petroleum as poisonous at high concentrations?
1. Oxides of sulphur
2. Oxides of nitrogen
3. Carbon monoxide
4. Carbon dioxide
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 1, 2 and 3 only
(c) 2, 3 and 4 only
(d) 1, 2, 3 and 4

Answer: (b). NCERT calls carbon dioxide a greenhouse gas, not a poison (NCERT 2020-21, p. 279).

6. Consider the following statements about check dams on level terrain, as described by NCERT:
1. Their main purpose is to recharge the ground water beneath.
2. Most of them hold water throughout the year.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Answer: (a). Only the largest hold water year round; most dry up six months or less after the monsoons (NCERT 2020-21, p. 277).

7. In the kulh system of Himachal Pradesh described by NCERT, during the planting season water was used first by:
(a) the village nearest the source
(b) the village farthest from the source
(c) the largest village
(d) villages chosen by the Irrigation Department

Answer: (b). Then by villages progressively higher up (NCERT 2020-21, p. 276).

8. According to CGWB's 2025 national assessment, the stage of groundwater extraction for India as a whole is about:
(a) 45 per cent
(b) 61 per cent
(c) 80 per cent
(d) above 100 per cent

Answer: (b). 60.63% (CGWB, National Compilation on Dynamic Ground Water Resources of India, 2025).

9. Consider the following statements:
1. India's target of 500 GW of non-fossil energy capacity by 2030 was announced at COP26.
2. The NDC for 2031-35 targets 60 percent cumulative electric power installed capacity from non-fossil sources by 2035.
3. The NDC for 2031-35 targets a 47 percent reduction in the emissions intensity of GDP by 2035 from the 2005 level.
Which of the statements given above are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

Answer: (d). PIB, 1 November 2021 and 25 March 2026.

10. The definition "development that meets the needs of the present without compromising the ability of future generations to meet their own needs" comes from:
(a) Our Common Future
(b) The Limits to Growth
(c) The Stockholm Declaration
(d) Agenda 21

Answer: (a). The Brundtland Commission's report, ch. 2, para. 1.

11. In March 2026 the Union Cabinet extended the Jal Jeevan Mission up to:
(a) March 2026
(b) December 2026
(c) December 2028
(d) March 2030

Answer: (c). Cabinet decision of 10 March 2026, with total outlay raised to Rs 8.69 lakh crore.

12. Which one of the following is not among the three biodiversity hotspots that NCERT Class XII Biology names for India?
(a) Western Ghats and Sri Lanka
(b) Indo-Burma
(c) Himalaya
(d) Thar Desert

Answer: (d). NCERT Class XII Biology, ch. 13 (p. 224).

13. Consider the following statements about vehicle emission norms in India:
1. BS-VI was mandated for vehicles throughout the country from 1 April 2020.
2. India moved to BS-VI directly from BS-IV.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Answer: (c). PIB, 9 December 2019 and 7 October 2019.

📦 Revision Capsule

Sources

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