Glossary: ECO-02 Key Terms

Term	Definition	Context/Example
Biodiversity	Variety of life forms at genetic, species, and ecosystem levels	Earth has ~1.5M described species; true total ~8.7M
Genetic diversity	Variation in genes within a species	Rauwolfia vomitoria — different reserpine levels in Himalayan populations
Species diversity	Variety and abundance of species in a region	India: ~45,000 plants, ~100,000 animals
Ecological diversity	Variety of ecosystems/biomes in a region	India: deserts, rainforests, mangroves, wetlands, alpine meadows
Latitudinal gradient	Increase in species richness from poles to equator	Tropics > Temperate > Arctic
Species-area relationship	Mathematical relationship between area and species richness: log S = log C + Z log A	Z = 0.1–0.2 continents; 0.6–1.2 islands
Z value	Slope of species-area log-log curve	Low Z = gentle; High Z = steep
Biodiversity hotspot	Region with ≥1,500 endemic vascular plants AND ≥70% habitat loss	India has 4 (WISH)
Endemic species	Species found only in a specific geographic area	Lion-tailed macaque — Western Ghats only
IUCN Red List	Global database of species extinction risk	EX → EW → CR → EN → VU → NT → LC → DD → NE
In-situ conservation	Protection in natural habitat	National parks, wildlife sanctuaries, sacred groves
Ex-situ conservation	Protection outside natural habitat	Zoos, seed banks, cryopreservation
Cryopreservation	Storage of biological material at −196 °C in liquid nitrogen	Indefinite genetic preservation
HIPPO	Framework for biodiversity loss causes	Habitat, Invasive, Population, Pollution, cO-extinction
Invasive alien species	Non-native species disrupting native ecosystems	Nile perch, Lantana, water hyacinth
Co-extinction	Extinction of dependent species when host species goes extinct	Fig tree extinct → fig wasp extinct
Biophilia	Innate human affiliation with nature (E.O. Wilson)	Ethical basis for biodiversity conservation
Ecosystem services	Benefits ecosystems provide to humans (direct + indirect)	~$33 trillion/year (Costanza 1997)
CBD	Convention on Biological Diversity — 1992, Rio de Janeiro	3 goals: conservation, sustainable use, benefit-sharing
Biosphere reserve	UNESCO-designated zone with 3 zones: core, buffer, transition	India: 18 biosphere reserves; Nilgiri is first/largest
Sacred grove	Forest patch protected by local community on religious grounds	Meghalaya, Rajasthan, Western Ghats; IN-SITU conservation
Megadiverse country	One of 17 nations with disproportionately high biodiversity	India covers 2.4% land but has 8% of described species
Ramsar site	Wetland of international importance under Ramsar Convention	Chilika Lake (India's first, 1981)