📌 Chapter Snapshot
3
Levels of Biodiversity
4
India's Biodiversity Hotspots
101
Ramsar Sites in India (Aug 2026)
1948
IUCN Established
- Biodiversity is the variety of life on Earth at all levels — from genes and species to entire ecosystems.
- This chapter covers genetic, species and ecosystem diversity, plus alpha/beta/gamma spatial diversity, biodiversity hotspots, in-situ & ex-situ conservation methods, IUCN Red List categories, and the Ramsar Convention with India's 101 wetland sites as of August 2026 (state-wise).
⚡ QUICK RECALL
Biodiversity decreases from equator to poles — tropical regions (rainforests, coral reefs, islands) hold the highest biodiversity on Earth.
🧬 Types / Levels of Biodiversity
| Type | Measurement | Description |
|---|---|---|
| Genetic Diversity | Genes/alleles within a species | Variation within and among populations |
| Species Diversity | Species richness and evenness | Variety and relative abundance of species |
| Ecosystem Diversity | Variety of ecosystems, habitats and ecological processes | Distinct from alpha/beta/gamma spatial species diversity |
⚠ EXAM TRAP
Whittaker framework: alpha = local species diversity; beta = species turnover among communities; gamma = total regional species diversity. These are not synonyms for genetic, species and ecosystem diversity.
⚡ QUICK RECALL
Highest Biodiversity zones: Tropical Rainforests, Coral Reefs, Islands, Tropical Marine Zones. Largest Coral Reef → Great Barrier Reef (Australia), nicknamed "Rainforest of the Ocean".
🔥 Biodiversity Hotspots
- Hotspot criteria: at least 1,500 endemic vascular plant species and 30% or less of original natural vegetation remaining.
- Given by → Norman Myers (1988 AD).
India's Biodiversity Hotspots (4)
| # | Hotspot |
|---|---|
| 1 | Western Ghats, Sri Lanka region |
| 2 | Himalaya |
| 3 | Indo-Burma region |
| 4 | Sundaland, Nicobar Island group |
🏞 In-situ Conservation (On-site)
- National Parks
- Wildlife Sanctuaries
- Sacred Groves
- Biosphere reserves (natural-habitat conservation)
🧪 Ex-situ Conservation (Off-site)
- Biological Parks
- Zoos
- DNA Banks
- Cryopreservation and captive-breeding programmes
- Seed Banks, etc.
⚡ QUICK RECALL
In-situ = conservation "in the natural habitat" | Ex-situ = conservation "outside the natural habitat" — the Latin roots (in vs ex) directly hint at the meaning.
📕 Red Data Book / Endangered Species — IUCN
Full FormInternational Union for Conservation of Nature (IUCN)
Established1948
HeadquartersGland, Switzerland
ObjectiveConservation of rare species, nature and natural resources
Plant Red Data Book (historical)1978
Threatened Animals publication (historical)1988
IUCN Red List categories (evaluated risk sequence)
Extinct (EX)→Extinct in the Wild (EW)→
Critically Endangered→
Endangered→
Vulnerable→
Near Threatened (NT)→Least Concern (LC)
Examples of IUCN status differences
- Great Indian Bustard and White-rumped Vulture: Critically Endangered; Nilgai: Least Concern. Do not call every listed animal Endangered.
⚠ EXAM TRAP
The Red List system began in 1964. Plant Red Data Book (1978) and Red List of Threatened Animals (1988) are historical publications; threatened categories are CR, EN and VU. DD and NE are not ordered risk levels.
💧 Ramsar Convention — Conservation of Wetlands
PurposeConservation and wise use of all wetlands and their resources
Ramsar Convention signed2nd February, 1971 — Ramsar, Iran
Related observanceWorld Wetlands Day (2nd February)
Entry into force for India1 February 1982
Total Ramsar Sites in India101 (as of August 2026)
Highest Ramsar Sites — StateTamil Nadu (20)
Largest Ramsar SiteSundarbans (West Bengal)
Smallest Ramsar SiteRenuka (Himachal Pradesh)
⚠ EXAM TRAP
Ramsar Convention was signed in 1971 but India only joined in 1982 — an 11-year gap frequently tested as a standalone MCQ.
🗺 Ramsar Wetland Sites in India — State-wise (101 Sites, August 2026)
| State / UT | Ramsar Sites |
|---|---|
| Jammu & Kashmir | Hokera Wetland; Surinsar-Mansar Lakes; Wular Lake; Hygam Wetland Conservation Reserve; Shallbugh Wetland Conservation Reserve |
| Ladakh | Tso Kar Wetland Complex; Tsomoriri Lake |
| Himachal Pradesh | Chandertal Wetland; Pong Dam Lake; Renuka Wetland |
| Punjab | Beas Conservation Reserve; Harike Lake; Kanjli Lake; Ropar Lake; Keshopur-Miani Community Reserve; Nangal Wildlife Sanctuary |
| Haryana | Bhindawas Wildlife Sanctuary; Sultanpur National Park |
| Uttarakhand | Asan Conservation Reserve |
| Uttar Pradesh | Upper Ganga River; Nawabganj Bird Sanctuary; Parvati Arga Bird Sanctuary; Saman Bird Sanctuary; Samaspur Bird Sanctuary; Sandi Bird Sanctuary; Sarsai Nawar Jheel; Sur Sarovar; Haiderpur Wetland; Bakhira Wildlife Sanctuary; Patna Bird Sanctuary; Shekha Jheel Bird Sanctuary; Jai Prakash Narayan Bird Sanctuary (Surha Tal) |
| Sikkim | Khachoedpalri Wetland |
| Assam | Deepor Beel |
| Chhattisgarh | Kopra Jalashay |
| Arunachal Pradesh | Glaw Lake |
| Manipur | Loktak Lake |
| Tripura | Rudrasagar Lake |
| Mizoram | Pala Wetland |
| Rajasthan | Keoladeo Ghana National Park; Sambhar Lake; Menar Wetland Complex; Khichan Wetland; Siliserh Lake |
| Gujarat | Nalsarovar; Thol Lake Wildlife Sanctuary; Wadhvana Wetland; Khijadia Wildlife Sanctuary; Chhari Dhand |
| Madhya Pradesh | Bhoj Wetlands; Sakhya Sagar; Sirpur Wetland; Yashwant Sagar; Tawa Reservoir |
| Maharashtra | Lonar Lake; Nandur Madhameshwar; Thane Creek |
| Goa | Nanda Lake |
| Karnataka | Ranganathittu Bird Sanctuary; Ankasamudra Bird Conservation Reserve; Aghanashini Estuary; Magadi Kere Conservation Reserve |
| Kerala | Ashtamudi Wetland; Sasthamkotta Lake; Vembanad-Kol Wetland |
| Jharkhand | Udhwa Lake Bird Sanctuary |
| Bihar | Kabartal Wetland; Nagi Bird Sanctuary; Nakti Bird Sanctuary; Gokul Jalashay; Udaipur Jheel; Gogabil Lake |
| West Bengal | East Kolkata Wetlands; Sundarban Wetland |
| Odisha | Bhitarkanika Mangroves; Chilika Lake; Satkosia Gorge; Tampara Lake; Hirakud Reservoir; Ansupa Lake |
| Andhra Pradesh | Kolleru Lake |
| Tamil Nadu | Point Calimere Wildlife and Bird Sanctuary; Koonthankulam Bird Sanctuary; Chitrangudi Bird Sanctuary; Karikili Bird Sanctuary; Pichavaram Mangrove; Pallikaranai Marsh Reserve Forest; Gulf of Mannar Marine Biosphere Reserve; Vembannur Wetland Complex; Vellode Bird Sanctuary; Udhayamarthandapuram Bird Sanctuary; Vedanthangal Bird Sanctuary; Suchindram Theroor Wetland Complex; Vaduvur Bird Sanctuary; Kanjirankulam Bird Sanctuary; Karaivetti Bird Sanctuary; Longwood Shola Reserve Forest; Kazhuveli Bird Sanctuary; Nanjarayan Bird Sanctuary; Sakkarakottai Bird Sanctuary; Therthangal Bird Sanctuary |
⚡ QUICK RECALL
Tamil Nadu alone has 20 Ramsar sites — the highest of any state — mostly bird sanctuaries clustered in the state's wetland belt.
📋 Master Quick-Revision Table
| Topic | Key Fact |
|---|---|
| Biodiversity — Definition | Variety of life at all levels from genes to ecosystem |
| Alpha (α) Diversity | Local species diversity within a community |
| Beta (β) Diversity | Species turnover/compositional differences among communities |
| Gamma (γ) Diversity | Total regional species diversity | Whittaker framework |
| Highest Biodiversity | Tropical Rainforests, Coral reefs, Islands, Tropical marine zones |
| Largest Coral Reef | Great Barrier Reef (Australia) |
| Biodiversity Hotspots — Concept | Norman Myers (1988 AD) |
| India's Hotspots (4) | Western Ghats+Sri Lanka | Himalaya | Indo-Burma | Sundaland+Nicobar |
| In-situ Conservation | National parks, Wildlife sanctuaries, Sacred groves, Biosphere reserves |
| Ex-situ Conservation | Biological parks, Zoos, DNA banks, Seed banks |
| IUCN | 1948 | Gland, Switzerland | Red List system: 1964; historical publications: plants 1978, animals 1988 |
| Red List categories | EX → EW → CR → EN → VU → NT → LC; threatened = CR/EN/VU |
| Ramsar Convention | 2 February 1971 | Ramsar, Iran | World Wetlands Day |
| India joined Ramsar | 1 February 1982 (entry into force) |
| Ramsar Sites in India | 101 (as of August 2026) |
| Most Ramsar Sites — State | Tamil Nadu — 20 |
| Largest Ramsar Site | Sundarbans (West Bengal) |
| Smallest Ramsar Site | Renuka (Himachal Pradesh) |