Direct (Economic) Value — Tangible, Marketable
| Category | Examples | Economic Significance |
|---|---|---|
| Food crops | Rice (Oryza sativa), wheat, maize | Global food security |
| Timber | Teak, sal, rosewood | Construction, furniture |
| Medicinal plants | Cinchona (quinine), Digitalis (digoxin), Rauwolfia (reserpine) | ~25% of pharmaceuticals derived from plants |
| Fibres | Cotton, jute, hemp | Textiles industry |
| Genetic resources | Wild crop relatives for breeding | Disease-resistant/drought-tolerant cultivar development |
Indirect (Ecological) Value — Ecosystem Services
| Service | Mechanism | Estimated Value |
|---|---|---|
| Nutrient cycling | Decomposers, nitrogen fixers | Essential — no substitute |
| Pollination | Insects, birds, bats | ~$235 billion/year globally |
| Carbon sequestration | Forests absorb CO₂ | 100/tonne CO₂ |
| Water purification | Wetlands filter pollutants | $billions saved in water treatment |
| Flood control | Mangroves, wetlands | Protects coastal communities |
| Soil formation | Earthworms, root systems | Irreplaceable on human timescales |
| Climate regulation | Forest transpiration, albedo | Global climate stability |
| TOTAL (Costanza 1997) | All ecosystem services combined | ~$33 trillion/year |
Ethical (Intrinsic) Value
- E.O. Wilson's "biophilia": humans have evolutionary affiliation with nature
- Every species has intrinsic right to existence — independent of human utility
- Intergenerational equity: we must preserve biodiversity for future generations
- Deep ecology argument: nature has value in itself, not just as a resource
Practical Application Questions for NEET
- "Honey bees provide pollination services — what value category is this?" → Indirect/Ecological
- "Cinchona provides quinine — what value?" → Direct/Economic
- "Biophilia refers to what kind of value?" → Ethical/Intrinsic
- "Nutrient cycling in an ecosystem represents what type of biodiversity value?" → Indirect