Quick Revision

The three R's are Reduce, Reuse, Recycle. Reduce: Use less (avoid unnecessary purchases, reduce electricity usage). Reuse: Use items again without processing (refill bottles, donate clothes). Recycle: Process waste materials to make new products (paper recycling, plastic recycling). Reduce is the most effective strategy.

Rainwater harvesting is the collection and storage of rainwater for future use instead of letting it run off. Methods: 1. Rooftop harvesting — collecting rainwater from roofs into storage tanks. 2. Check dams — small barriers across streams to store water. 3. Recharge pits — allowing rainwater to seep into ground to recharge groundwater. 4. Khadin, johads, bandharas — traditional water harvesting structures in India. Importance: (1) Recharges groundwater. (2) Reduces flood risk. (3) Provides water during dry seasons. (4) Reduces dependence on borewells. (5) Cost-effective and sustainable.

The Chipko Movement (1974) was a forest conservation movement in the Garhwal Himalayas (Uttarakhand). Villagers, especially women led by Gaura Devi, hugged trees to prevent contractors from cutting them. 'Chipko' means 'to hug'. The movement successfully stopped deforestation and raised awareness about the importance of forests for local communities (fuel, fodder, soil conservation, water).

Forests and wildlife should be conserved because: 1. Biodiversity — forests harbour a vast variety of plants, animals, and microorganisms. 2. Ecological balance — forests regulate climate, rainfall, and water cycle. 3. Economic value — timber, medicinal plants, honey, resin, latex. 4. Soil conservation — tree roots prevent soil erosion. 5. Carbon sink — forests absorb CO₂, reducing global warming. 6. Livelihood — tribal and local communities depend on forests. 7. Water conservation — forests act as natural watersheds. Wildlife conservation maintains food chains and ecological balance. Loss of one species can affect the entire ecosystem.

Exhaustible resources: Available in limited quantity, will get depleted if used continuously. Examples: coal, petroleum, natural gas, minerals, forests. Inexhaustible resources: Available in unlimited quantity, cannot be depleted by human activity. Examples: solar energy, wind energy, tidal energy, geothermal energy. Note: Some resources like water and forests are renewable but can become exhaustible if overused faster than they regenerate.