The earth will not continue to offer its harvest, except with faithful stewardship. — John Paul II
14.1 What Is Biodiversity?
Biodiversity (biological diversity) refers to the variety of life at three levels:
- Genetic diversity — variation within species
- Species diversity — number of different species
- Ecosystem diversity — variety of habitats and ecological communities
India is one of 17 megadiverse countries, hosting ~7–8% of world's species despite covering only 2.4% of land area.
14.2 Importance of Biodiversity
- Ecological — nutrient cycling, pollination, soil formation, climate regulation
- Economic — food, medicine, timber, tourism
- Scientific — research and genetic resources
- Cultural — sacred groves, tribal traditions, aesthetic value
Ecosystem services from forests, wetlands, and coral reefs sustain human livelihoods.
14.3 Threats to Biodiversity
| Threat | Example in India |
|---|---|
| Habitat loss | Deforestation in Western Ghats |
| Pollution | Industrial effluents in rivers |
| Climate change | Coral bleaching in Lakshadweep |
| Invasive species — Lantana, water hyacinth | |
| Overexploitation — poaching of tigers, rhinos |
Hotspots — regions with high endemism and threat (Western Ghats, Himalayas, Indo-Burma, Sundaland).
14.4 Conservation Strategies
- In-situ — protecting species in natural habitats: national parks, wildlife sanctuaries, biosphere reserves (e.g. Sundarbans, Kaziranga, Nilgiri Biosphere Reserve)
- Ex-situ — outside natural habitat: zoos, botanical gardens, seed banks
- Legal — Wildlife Protection Act (1972), Forest Conservation Act, Biodiversity Act (2002)
- International — CITES, Convention on Biological Diversity
Community conservation: Chipko movement, sacred groves of Meghalaya, Bishnoi tradition.
Chapter Summary
- Biodiversity exists at genetic, species, and ecosystem levels
- India is megadiverse; biodiversity supports ecology, economy, and culture
- Habitat loss, pollution, and climate change are major threats
- In-situ and ex-situ conservation; legal and community-based protection
- Sustainable use ensures resources for future generations
Exercises (NCERT)
- Exercise 1 — levels and importance of biodiversity
- Exercise 2 — threats to biodiversity in India
- Exercise 3 — in-situ vs ex-situ conservation; protected area examples