Natural Resources — Class 10 Biological Science
"We do not inherit the Earth from our ancestors. We BORROW it from our children."
1. Resources — The Foundation of Life
Renewable Resources
Can be REPLENISHED naturally over time. Solar energy. Wind. Water. Forests. 'RENEWABLE ≠ UNLIMITED. Groundwater is renewable — but if you pump FASTER than it recharges, it DEPLETES. Forests are renewable — but if you cut FASTER than they regrow, they DISAPPEAR. Sustainable use = use at a rate ≤ rate of renewal.'
Non-Renewable Resources
FINITE. Once used, GONE — on human timescales. Coal. Petroleum. Natural gas. Minerals (iron, copper, gold). 'Fossil fuels formed over MILLIONS of years. We are burning them in DECADES. This is the most one-sided trade in history.'
2. Forests and Wildlife
Why Forests Matter
- Produce OXYGEN. Absorb CO₂ (carbon sink — climate regulation). Home to 80% of terrestrial BIODIVERSITY. Regulate WATER CYCLE. Prevent SOIL EROSION. Provide: timber, medicine, food, livelihood for MILLIONS of people.
Biodiversity Hotspots in India
India has 4 of the world's 36 biodiversity hotspots: WESTERN GHATS (one of the world's 8 "hottest" biodiversity hotspots — incredible endemic species). HIMALAYAS (eastern Himalayas especially rich). INDO-BURMA (includes Northeast India). SUNDALAND (Nicobar Islands).
Conservation — Protected Areas
| Type | Description | India Count | Example |
|---|---|---|---|
| National Park | STRICTEST protection. No human activity allowed (except sanctioned tourism/research). | 106 | Jim Corbett (Uttarakhand — India's FIRST, 1936). Kaziranga (Assam — one-horned rhino). Gir (Gujarat — Asiatic lion). |
| Wildlife Sanctuary | Some human activities allowed (grazing, collection of minor forest produce). | 565+ | Bharatpur Bird Sanctuary (Keoladeo — Rajasthan). |
| Biosphere Reserve | LARGE areas. Multiple use zones (core, buffer, transition). | 18 | Nilgiri (first). Sundarbans. Nanda Devi. Gulf of Mannar. |
Project Tiger (1973) — India's Flagship Conservation Programme
Launched from Jim Corbett National Park. 54 tiger reserves across India. 'India is home to ~75% of the world's wild tigers. Project Tiger is the reason they still EXIST. In 1973: tiger population had crashed to ~1,800 (from ~40,000 a century earlier). Today: ~3,100+ (2022 census). The tiger is RECOVERING. But poaching and habitat loss remain SERIOUS threats.'
Endangered Species in India
Bengal Tiger. Asiatic Lion (ONLY in Gir forest, Gujarat — ~600 individuals). One-horned Rhinoceros (Kaziranga). Great Indian Bustard (Rajasthan — critically endangered. ~150 left). Gharial (rivers of North India). Olive Ridley Turtles (mass nesting on Odisha coast).
Red Data Book
The International Union for Conservation of Nature (IUCN) maintains the RED LIST — classifying species by extinction risk: Extinct → Extinct in the Wild → Critically Endangered → Endangered → Vulnerable → Near Threatened → Least Concern.
3. Water Resources
The Scarcity Paradox
India: 4% of world's freshwater. ~18% of world's population. RESULT: chronic WATER STRESS. 'Water scarcity is not just about LOW RAINFALL. It's about: uneven DISTRIBUTION (Cherrapunji gets 11,000 mm. Jaisalmer gets 200 mm). OVER-EXPLOITATION (Punjab's groundwater — dropping 1 METRE PER YEAR). POLLUTION (70% of surface water is polluted — unfit for drinking). WASTAGE (leaking taps, flood irrigation).'
Dams — Benefits and Costs
Benefits: Irrigation (dry season farming). Hydropower (clean energy). Flood control. Drinking water supply. Costs: DISPLACEMENT of people (millions displaced — many inadequately rehabilitated). Submergence of forests and farmland. Ecological disruption (fish migration blocked. River ecology changed). Siltation (reservoirs fill up over time).
Rainwater Harvesting
CATCH rain where it FALLS. Rooftop harvesting: collect rain from roof → filter → store in tank or RECHARGE groundwater. Compulsory in TAMIL NADU (first state to mandate it). Traditional systems: Rajasthan (tankas, khadins). Himachal (kuls). 'Rainwater harvesting is DECENTRALISED. Every building — home, school, office — can do it. It costs LITTLE. It transforms water security.'
4. Coal and Petroleum — Fossil Fuels
How They Formed
MILLIONS of years ago: plants (coal) and marine organisms (petroleum) died → buried under sediment → subjected to HIGH PRESSURE and TEMPERATURE → transformed over geological time. 'The energy in fossil fuels is ANCIENT SUNLIGHT — captured by photosynthesis millions of years ago, compressed and stored underground.'
Coal
Formed from BURIED PLANT MATTER (Carboniferous period — ~300 million years ago). Uses: Thermal power plants (electricity). Iron and steel industry. India: 2nd largest producer (after China). Major coalfields: Jharia, Raniganj (Jharkhand/West Bengal).
Petroleum
Formed from MARINE ORGANISMS. Uses: Transport fuels (petrol, diesel, aviation fuel). Petrochemicals (plastics, synthetic fibres, fertilisers). India IMPORTS ~85% of its crude oil. Major domestic fields: Mumbai High (offshore). Digboi, Assam (OLDEST oil well in India — 1867).
Why We Must Transition
- Fossil fuels are FINITE — they WILL run out. 2. Burning them releases CO₂ → GLOBAL WARMING → climate change. 3. Air pollution (Delhi's air quality among the world's worst — largely from fossil fuel combustion). 'The answer: RENEWABLES. Solar. Wind. Hydro. India's target: 500 GW renewable capacity by 2030. The TRANSITION has BEGUN. It must ACCELERATE.'
5. The 3 R's — Reduce, Reuse, Recycle
REDUCE: The MOST important R. Use LESS. Refuse single-use plastic. Walk or cycle instead of driving short distances. REUSE: Use again. Cloth bags (not plastic). Glass bottles. Donate old clothes, books, electronics instead of throwing. RECYCLE: Convert waste into NEW products. Paper. Glass. Metal. E-waste (contains precious metals — gold, silver, copper — AND toxic materials — lead, mercury. Must be recycled by SPECIALISED recyclers).
6. AP Context — Natural Resources in Andhra Pradesh
- Forests: Nallamala Hills (part of Eastern Ghats — teak, red sanders). Mangroves in Godavari-Krishna delta (Coringa Wildlife Sanctuary — second largest mangrove forest on India's east coast).
- Water: Godavari and Krishna rivers — lifelines of AP. Groundwater in Rayalaseema is SCARCE. Rayalaseema Drought — chronic water shortage. Check dams and watershed programmes are critical.
- Energy: AP is a LEADER in solar energy (Anantapur district — one of India's largest solar parks). Wind energy (near Kadapa, Anantapur).
7. Common Mistakes
- 'Renewable = unlimited' — Renewable ≠ unlimited. Groundwater and forests are renewable but CAN be depleted through overuse.
- 'Fossil fuels formed from dinosaurs' — Coal formed from PLANTS (peat bogs). Petroleum from MARINE MICROORGANISMS (plankton). Not dinosaurs.
- 'Recycling solves everything' — Recycling is the THIRD R — after Reduce and Reuse. Reducing consumption is MORE effective.
8. AP SSC Exam Focus
| Topic | Marks |
|---|---|
| Renewable vs Non-Renewable | 2-3 |
| Forests — conservation, hotspots | 3-4 |
| Water — scarcity, rainwater harvesting | 3-4 |
| Fossil fuels — coal and petroleum | 2-3 |
| 3 R's | 2-3 |
9. Biogeochemical Cycles — Detailed Study
'MATTER CYCLES through ecosystems. Unlike energy (which flows one way), matter is RECYCLED. This is why Earth has the same carbon, nitrogen, and water that it had billions of years ago.'
Water Cycle (Hydrological Cycle)
Evaporation (Sun heats water → water vapour) → Transpiration (plants release water vapour) → Condensation (vapour forms clouds) → Precipitation (rain, snow) → Runoff (water flows into rivers, lakes, oceans) → Seepage (water percolates into groundwater).
'Only ~0.024% of Earth's water is readily available for human use. The rest is salt water (97%) or frozen in glaciers (2%). This is why water CONSERVATION is so critical.'
Carbon Cycle
Photosynthesis (plants absorb CO₂ from atmosphere → convert to glucose and other organic compounds) → Respiration (all organisms release CO₂ when they break down glucose) → Decomposition (decomposers break down dead matter → release CO₂) → Combustion (burning fossil fuels and biomass → releases CO₂) → Ocean absorption (oceans absorb CO₂ from atmosphere).
'Human activity has BROKEN the carbon cycle. By burning fossil fuels, we release carbon that was locked underground for millions of years. The atmosphere now has ~50% MORE CO₂ than before the Industrial Revolution. This is the PRIMARY driver of CLIMATE CHANGE.'
Nitrogen Cycle
The atmosphere is 78% nitrogen (N₂). But MOST organisms cannot use N₂ directly. It must be 'FIXED' into usable forms (ammonia, nitrates).
- Nitrogen Fixation: Rhizobium bacteria (in root nodules of legumes) and free-living bacteria (Azotobacter) convert N₂ → AMMONIA (NH₃). Lightning also fixes small amounts of nitrogen.
- Nitrification: Nitrosomonas converts ammonia → NITRITES. Nitrobacter converts nitrites → NITRATES (usable by plants).
- Assimilation: Plants absorb nitrates → use them to make PROTEINS and nucleic acids (DNA). Animals eat plants → get nitrogen.
- Ammonification: Decomposers convert dead organisms and waste → AMMONIA.
- Denitrification: Denitrifying bacteria (Pseudomonas) convert nitrates → N₂ gas → released back to atmosphere.
'The nitrogen cycle is COMPLEX but ESSENTIAL. Without nitrogen-fixing bacteria, plants cannot grow. Without plants, animals cannot survive.'
Oxygen Cycle
Photosynthesis (plants release O₂) → Respiration (all organisms consume O₂) → Combustion (burning consumes O₂) → Ozone formation (O₂ → O₃ in stratosphere).
10. Fossil Fuels — Formation and Impact
Coal Formation — Step by Step
Step 1: Millions of years ago — lush swamp forests with giant ferns and trees (Carboniferous period). Step 2: Plants died → fell into SWAMPS → partially decomposed in OXYGEN-POOR water → formed PEAT. Step 3: Peat buried by sediment → subjected to HIGH PRESSURE and TEMPERATURE → transformed over millions of years. Step 4: Peat → Lignite (soft brown coal) → Bituminous (soft coal) → Anthracite (hard coal — highest carbon content, burns hottest).
'Coal is graded by CARBON CONTENT. Anthracite has ~86-97% carbon. Lignite has only ~60-70%. India has mainly BITUMINOUS coal.'
Petroleum Formation — Step by Step
Step 1: Marine MICROORGANISMS (plankton, algae) died → sank to ocean floor. Step 2: Buried by sediment → subjected to high pressure and temperature. Step 3: Organic matter transformed into KEROGEN → then into CRUDE OIL and NATURAL GAS. Step 4: Oil migrates through porous rock → gets trapped under IMPERMEABLE rock (cap rock) → forms OIL RESERVOIR.
'Petroleum is a MIXTURE of hydrocarbons. It is separated into different fractions by FRACTIONAL DISTILLATION at refineries: Petrol (gasoline), Diesel, Kerosene, Aviation fuel, LPG, Naphtha (for plastics), Lubricants, Bitumen (for roads).'
Environmental Impact of Fossil Fuels
Air Pollution: Burning coal releases SO₂ and NOₓ → ACID RAIN. PM 2.5 particles → respiratory diseases. Climate Change: CO₂ is a GREENHOUSE GAS → traps heat → global warming. Oil Spills: Catastrophic for marine ecosystems (Exxon Valdez, Deepwater Horizon). Mining Damage: Coal mining destroys forests, pollutes water, displaces communities.
11. Management of Natural Resources
'The Constitution of India directs the state to PROTECT and IMPROVE the environment (Article 48A). Citizens have a FUNDAMENTAL DUTY to protect the natural environment (Article 51A(g)).'
Forest Management
- Participatory Forest Management: Involving LOCAL COMMUNITIES in forest protection. The Joint Forest Management (JFM) programme involves village committees (VSS — Vana Samrakshana Samithi in AP).
- Social Forestry: Planting trees on COMMON lands — roadsides, railway lines, canal banks, village commons.
- Sacred Groves: Patches of forest protected by TRADITIONAL RELIGIOUS BELIEFS. In AP: Devarkadu, Pavitrakavanalu in the Eastern Ghats.
Water Management
- Watershed Management: Treating a WATERSHED as a unit. Building check dams, contour bunding, afforestation → RECHARGES groundwater, reduces soil erosion.
- Drip Irrigation: Water delivered DIRECTLY to plant roots through tubes. Reduces water use by 50-70%.
- Neeru-Meeru ('Water and You'): A PEOPLE'S MOVEMENT for water conservation in Andhra Pradesh. Involves building check dams, desilting tanks, and planting trees.
12. Chipko Movement — India's Most Famous Conservation Movement
'In 1973, in the Himalayan village of Mandal (Uttarakhand), villagers RESISTED the auction of forests to a sports goods company. They HUGGED the trees — refusing to let loggers cut them. This was the CHIPKO MOVEMENT.'
Leaders: Chandi Prasad Bhatt (founded Dasholi Gram Swarajya Mandal — organised the protest). Gaura Devi (led the women of Reni village in a CHIPKO action in 1974 — faced armed loggers and REFUSED to move).
Impact: The movement FORCED the government to ban commercial logging in the Uttarakhand Himalayas for 15 years. It INSPIRED conservation movements across India. 'Chipko means "to HUG" — the women of Reni village hugged the trees to protect them. This was a NON-VIOLENT, WOMEN-LED movement that showed the world that ordinary people CAN protect their environment.'
13. AP-Specific Conservation
- Coringa Wildlife Sanctuary: Second largest MANGROVE forest on India's east coast. Located in Godavari-Krishna delta. Home to fishing cats, otters, and migratory birds (flamingos, storks, pelicans).
- Kolleru Lake: Largest FRESHWATER lake in India (between Krishna and Godavari deltas). A Ramsar site (internationally important wetland). Home to migratory birds from Siberia and Eastern Europe. Threats: encroachment for AQUACULTURE (fish and shrimp ponds).
- Nallamala Forest: Part of the Eastern Ghats. Rich in biodiversity. Teak, red sanders (endemic to AP — highly valuable, often illegally logged). Nagarjuna Sagar-Srisailam Tiger Reserve — the LARGEST tiger reserve in India (3,728 km²).
- Sri Venkateswara National Park (Tirumala hills): Home to the endangered SLENDER LORIS and many endemic plant species.
14. Common Mistakes (Additional)
- 'Coal and petroleum are minerals' — They are FOSSIL FUELS, not minerals. Minerals have a DEFINITE CHEMICAL COMPOSITION (e.g., iron ore, bauxite). Fossil fuels are organic remains.
- 'All forests absorb equal amounts of CO₂' — TROPICAL rainforests absorb the MOST. Old-growth forests are NET ZERO (absorb as much as they release). Plantations of single species are LESS effective than natural forests.
- 'Rainwater harvesting is only for rural areas' — Urban areas in India face CRITICAL water shortages. Rooftop rainwater harvesting is increasingly MANDATORY in Indian cities (Chennai was the first).
15. Self-Test Questions
- Differentiate between RENEWABLE and NON-RENEWABLE resources with TWO examples each.
- Draw a simple diagram of the CARBON CYCLE. Explain how human activities have affected it.
- What is NITROGEN FIXATION? Name the bacteria responsible.
- Explain the CHIPKO MOVEMENT. Who were its leaders?
- Describe the formation of COAL. Name the different types of coal.
- What are the environmental impacts of burning FOSSIL FUELS?
- What is WATERSHED MANAGEMENT? How does it help in water conservation?
- Name THREE biodiversity hotspots in India. Why are they important?
- What is PROJECT TIGER? When was it launched? What has been its impact?
- Explain the 3 R's — REDUCE, REUSE, RECYCLE. Which is the most important and why?
Answers to Selected Questions: Q3: Nitrogen fixation is the conversion of atmospheric N₂ gas into AMMONIA (NH₃). Bacteria: Rhizobium (in root nodules of legumes), Azotobacter (free-living in soil). Q9: Project Tiger was launched in 1973 from Jim Corbett National Park to protect the Bengal tiger. India's tiger population has grown from ~1,800 in 1973 to ~3,100+ in 2022. India now has 75% of the world's wild tigers.
