Nature’s Treasures

Natural resources are materials and sources of energy obtained from nature. Air, water, sunlight, forests, soil, rocks, minerals and fossil fuels support life and human activities. They are connected: a crop uses sunlight, water, air and soil rather than one isolated resource.

Human-made resources are things people produce using materials, energy and knowledge. A bicycle, electric bulb, piece of furniture or solar panel is human-made; the metals, wood and energy used to make it have natural sources. Calling a product human-made does not mean it is independent of nature.

Ask two questions about an object: what is used directly, and what was needed earlier to produce it? This makes resource use visible beyond the water coming out of a tap or the fuel entering a vehicle.

The oxygen in air supports human respiration and that of many other organisms. Activity 11.1 draws attention to breathing; ordinary comfortable breathing is enough for this observation. Do not turn breath-holding into a competition or deliberately continue until uncomfortable.

NCERT represents air with 100 squares: approximately78 parts nitrogen,21 parts oxygen and1 part argon, carbon dioxide and other gases. These are rounded proportions for dry air. Real air also contains variable water vapour, so the diagram is not a fixed account of humidity.

A percentage means parts per100. The gases are mixed; the grid does not mean nitrogen and oxygen occupy separate layers of the atmosphere. A change in smell alone cannot identify a pollutant or measure air quality.

Wind is moving air. Rustling leaves, swaying clothes and a fluttering book page show its effects. A breeze and a storm differ in strength, but both involve moving air.

Activity 11.2 makes a paper firki from a square of paper: cut towards the centre along the diagonals without cutting through the centre, fold alternate corners in, and fix them loosely to a support so the wheel can rotate. Use scissors and the pin with suitable supervision. Compare a gentle airflow with still air; the activity is not a measurement of electricity output.

Wind can turn blades to do mechanical work, such as pumping water or milling grain, or drive a generator to produce electricity. A wind farm contains many wind turbines. NCERT names Muppandal in Tamil Nadu, Jaisalmer in Rajasthan and Brahmanvel in Maharashtra; these are examples, not a current ranking of installed capacity.

Water is used for drinking, cooking, cleaning, washing, growing crops, livestock and industry. It covers much of Earth’s surface, mostly as saline oceans and seas. Freshwater also occurs as ice and snow, surface water and groundwater, with very different accessibility.

Saline water is unsuitable for ordinary drinking and many other uses without appropriate treatment or a suitable process. It is too broad to say it has no industrial uses at all. Likewise, freshwater is not automatically safe to drink: pollution and treatment matter.

Water availability differs between places and seasons. Access also depends on infrastructure, distance, quality and cost. Water cycling through nature does not guarantee an equal or unlimited local supply.

Household waste, litter and untreated discharges from homes or industry can pollute water. Reducing use and preventing contamination are complementary actions. Keeping rubbish out of a river is different from merely collecting some floating litter after it enters.

Activity 11.3 lists hand washing, laundry, utensil washing, showers, cooking, gardening and brushing teeth. For each, identify actual avoidable waste and a suitable remedy. Turn off unnecessary running taps, report leaks and use amounts appropriate to the task; do not reduce water needed for hygiene or safe food preparation.

Rainwater harvesting collects rainfall for later use. Rooftop systems direct runoff to storage; traditional systems such as Rajasthan’s bawadis and Gujarat’s vavs can store rainwater and receive seepage. The exact water source and design of a particular stepwell need local evidence, not an assumption that every structure works identically.

Harvesting or reusing water does not by itself establish drinking-water safety. Keep catchments and storage maintained, protect stored water from contamination, and match any treatment to its intended use. World Water Day is observed on 22 March; the chapter uses it as an opportunity to discuss water care.

1. 1

   Record the starting situation

   Choose a small home or school area. Record the task, visible waste, leaks and available evidence. If you measure volume, use the same method and period each time; do not invent a total.

2. 2

   Choose a practical action

   Repair or report a leaking tap, close taps when not needed, improve watering practice, or propose a suitable collection system with responsible staff. Decide who will act and what resources are needed.

3. 3

   Check the result fairly

   Repeat observations over a comparable period after the action. Note changes in attendance, weather or activities that could affect water use, rather than attributing every difference to the intervention.

4. 4

   Keep it working

   Assign maintenance and review dates. Report failures, protect hygiene and water quality, and explain what reduced demand or pollution could mean for the local environment.

Sunlight provides heat and light and supports photosynthesis in green plants. A cow gains energy by eating grass; the grass used sunlight to make food. The immediate food source and the earlier energy source are both relevant. Standing in sunshine does not supply the cow’s food energy in the same way.

Solar heat can dry clothes, chillies or mango pieces and can be used in solar cookers and water heaters. Photovoltaic panels produce electricity from light. A solar water heater and an electricity-generating panel perform different jobs.

The solar cooker in end question10 uses energy from sunlight. A benefit is reduced need for a fuel while cooking; a limitation is dependence on adequate sunshine, timing and equipment. Stored food or energy is not instantly lost during a few cloudy days.

For the family in question13, low sunlight would reduce solar-panel generation according to conditions; a gas stove can still use its stored fuel, and a wind-driven pump can still work if suitable wind is available. Darkness does not automatically stop wind. Distinguish a cloudy week from the hypothetical disappearance of the Sun, and do not assume an unmentioned battery or backup system.

Forests include trees, shrubs, herbs and many other organisms. They provide habitats, food and materials such as wood, fruits, fibres, gums and other plant products. Organisms depend on one another; removing trees can affect much more than the harvested wood.

Roots and vegetation help hold soil, while leaf litter and other organic material decompose and return nutrients. The forest floor can store moisture and support decomposers. This links habitat protection to the condition of soil and water.

Regrowing trees is not the same as immediately restoring a mature forest. Soil, species relationships, habitat structure and the time needed for growth all matter. Leave resources for wildlife and manage harvesting so regeneration can occur.

NCERT discusses sacred groves, the Chipko movement of the early 1970s and women’s participation in protecting trees in what is now Uttarakhand. It also introduces Van Mahotsav, a forest festival celebrated in July. These examples support conservation; no current forest-cover trend or quantified plantation outcome is asserted here.

Soil can include mineral particles, organic matter, water, air and living organisms. Spaces between particles help roots access air and grow. Earthworms can help mix and loosen some soils; an absence of visible worms in a small sample does not mean that the sample contains no life.

Weathering breaks rocks down through physical, chemical and biological processes; organic material and other processes also contribute to soil development. Productive soil can take a long time to develop and can be lost much faster through erosion or degradation. Different soils support different uses.

Rocks are made of minerals. The book gives slate roofing, laterite building blocks, granite, sandstone, marble and historical stone tools as examples of uses. Metals such as iron, copper, aluminium and gold can be obtained from suitable mineral deposits; not every rock is an economically usable source of each metal.

Electronic devices use many mineral-derived materials. Their exact number and composition depend on the device, so the book’s phone example is not a fixed count for every model. Reuse and responsible material recovery reduce demand, while extraction and construction choices also affect land.

1. 1

   Choose and label safe samples

   For Activity 11.4, compare small samples from suitable accessible sites with permission. Record where each came from. Avoid visibly contaminated areas and wash hands after handling.

2. 2

   Write the initial expectation

   Record what you expect to find before close observation. Keep this separate from the observations in Table 11.2.

3. 3

   Inspect without inventing identification

   Compare colour, visible particles, texture and organisms with the unaided eye and a magnifying lens. A lens can reveal more detail but does not show every microorganism or establish soil chemistry.

4. 4

   Explain the comparison and its limits

   Record actual differences. Colour alone does not prove fertility, pollution or a specific mineral. Note sample size and conditions; do not fill the table with guessed results.

Coal, petroleum and natural gas are fossil fuels formed from ancient biological material over geological time. Petrol, diesel and kerosene are petroleum products. Their formation is far too slow to replace the amounts consumed during ordinary human timescales.

Coal is used to generate electricity; natural gas can be used for cooking, power generation and, as CNG, in vehicles. LPG is another gaseous domestic fuel. CNG and LPG are not identical products, and neither is renewable merely because it is a gas.

Activity 11.5 surveys local vehicles and records their actual fuel or energy source in Table 11.3. Petrol is a common answer for the book’s scooter example, but not every two-wheeler uses it: electric models exist. Ask or use reliable information instead of guessing fuel solely from appearance.

Burning fuels can release carbon dioxide and other air pollutants; the pollutant mix depends on fuel, equipment and combustion. “Cleaner than” is a comparison, not a claim of no emissions. All-electric vehicles have no tailpipe exhaust, but electricity production, manufacturing and disposal can still have environmental impacts.

Reduce unnecessary fuel use through suitable walking, cycling, public transport, efficient use and maintenance. The chapter also asks for a map of coal-producing states: use dated official statistics for that extension rather than treating an unverified list or ranking as current.

Renewable resources are replenished by natural processes within a relevant period. Non-renewable resources are finite stocks that are not replaced on comparable human timescales. Availability, quality and rate of use matter as well as the category.

A renewable label does not mean unlimited or indestructible. A forest can be cleared faster than it regrows, and water or air can become polluted. Soil continues to form in nature, but productive soil lost through degradation is very slow to replace, which is why this chapter classifies it as non-renewable.

Electricity is an energy carrier produced from sources that can be renewable or non-renewable. A turbine, panel or machine is a human-made resource; its manufacture still uses natural materials and energy.

Use the sixteen end questions and further-learning prompts to explain a link between a resource, a use and a consequence. The following applications consolidate the remaining tasks without duplicating every definition.

1. Trace five everyday activities

   For Activity 11.6, washing clothes uses water; clay toys use soil-derived clay; collecting firewood uses plant material; making a kite can use paper from plant fibres and mineral-derived materials; breakfast uses food plus the resources needed to produce and cook it. Suggest a specific way to reduce avoidable use in each case.

2. Complete names and classifications

   The jumbled resource names are rock, forest, wind and water. Explain their classification using the timescale table. Machines are human-made. Nature supplies the underlying resources, but this does not imply that every human demand can be met without limits.

3. Give four roles for air

   Examples include human breathing, airflow turning a windmill, winnowing grain, and wind moving a sail or drying clothes. For each, identify the relevant process rather than treating every role as oxygen use. Smoke from combustion and dust-generating activities can degrade air quality; propose an action tied to the source.

4. Make planting a maintained activity

   Choose appropriate species and sites with responsible local guidance, permissions, water and space. Plan planting, protection and aftercare, then record survival and growth. Counting planted saplings alone does not establish a restored forest or permanent green cover.

5. Assess timber demand without ignoring costs

   For industrial or housing demand, consider necessity, reuse, alternatives, responsible sourcing and protection of habitats and soil. Large-scale removal can expose soil to erosion and disrupt nutrient return. Weigh these effects explicitly instead of assuming either that every cut is justified or that new planting instantly cancels the loss.

6. Keep extension work evidence-based

   Investigate an actual local water-harvesting practice and the uses of nearby rocks and minerals. For air-pollution interviews, distinguish reported experiences from measured pollution or a medical diagnosis. Record sources and dates. Propose two feasible actions and review results rather than inventing survey findings.

These are original learning questions. Choose the answer that explains the process or qualification; they are not claimed UPSC previous-year questions.