CAPF AC 2020 Q87: Environment & Ecology – Ecosystems & Ecology Concepts

CAPF AC 2020, Paper I (General Ability and Intelligence) · Environment & Ecology

Transition zone of varied natural vegetation occupying the boundary between two adjacent and differing plant communities is known as

Answer: (b) ecotone

Explanation

Ecotone

How to think: the question describes a place, a zone between two communities.

Succession and climax are about time.

A niche is a role.

Only an ecotone is a zone.

Term	Meaning	Verdict
Ecological succession	Slow change of a community over time	Incorrect
Ecotone	Transition zone between two different communities	Correct
Ecological niche	The role of a species in its ecosystem	Incorrect
Climax	The final stable community of a succession	Incorrect

Examples of ecotones:

An ecotone often has more species than either community beside it.

This is called the edge effect.

Answer: (b) ecotone.

(a) Incorrect. Succession is a change over time, not a zone on the ground.
(b) CORRECT. An ecotone is the transition zone between two differing plant communities.
(c) Incorrect. A niche is the functional role of a species.
(d) Incorrect. The climax is the last, stable stage of succession.

Ecotone = transition zone between two communities (mangrove, estuary, grassland); richer in species because of the edge effect.

Ecotone = boundary zone between two communities; edge effect.

Mixing up ecotone (a zone) with niche (a role).
Thinking an ecotone has fewer species; the edge effect usually gives it more.
Confusing ecotone with ecotype, a local variety of a species.

Educated guess: tone comes from a Greek word for tension. An ecotone is where two communities pull against each other.