Ecology & Biodiversity

Biodiversity & Conservation

Species diversity indices, hotspots and in-situ vs ex-situ conservation strategies.

PART 1

Topic Breakdown & Traps

The Engineering Principle

Biodiversity spans genetic, species and ecosystem levels. Species diversity combines *richness* (number of species) and *evenness* (relative abundances), captured by indices such as Shannon–Wiener (H) and Simpson's. Conservation is in-situ (protecting species in their habitat — national parks, sanctuaries, biosphere reserves) or ex-situ (zoos, seed/gene banks). Biodiversity hotspots are biologically rich, highly threatened regions.

The Core Formula Matrix

Shannon–Wiener index:

H = - \sum_{i} p_{i} ln p_{i}

(

p_{i}

= proportion of species

i

)

Simpson's index:

D = 1 - \sum p_{i}^{2}

In-situ: national parks, wildlife sanctuaries, biosphere reserves.

Ex-situ: zoos, botanical gardens, gene/seed banks, cryopreservation.

The ‘IIT Traps’

⚠
Higher H means greater diversity (richness *and* evenness).
⚠
In-situ ≠ ex-situ. In-situ protects within the natural habitat; ex-situ removes organisms from it.
⚠
A hotspot must be both species-rich and threatened, not merely diverse.

📚 Standard references

Conservation Biology — Richard B. Primack
Environmental Studies — Erach Bharucha · Biodiversity

PART 2

Progressive 3-Tier Question Suite

Q1MEDIUM2 Marks · NAT

A community has two species in equal proportions (

p_{1} = p_{2} = 0.5

). Its Shannon–Wiener index H (using ln) is _____.

Q2BASIC1 Mark · MCQ

Conservation of a species in its natural habitat (e.g. a national park) is termed:

Q3HARD1 Mark · MCQ

To qualify as a biodiversity hotspot, a region must be: