Home › PYQs › Environment › All questions › 2026 · Mangroves
UPSC Prelims 2026 · Environment · Nature’s Machinery
Which of the following best explain(s) the rationale for protecting mangrove ecosystems in the context of climate resilience?
- Mangroves reduce tidal energy and store freshwater, making them ideal sites for paddy cultivation in saline estuarine belts.
- Their salt-sensitive roots filter seawater, making mangroves key to converting coastal land into freshwater aquaculture zones.
- By withstanding tidal surges and offering biomass resources, mangroves function both as natural bio-shields and livelihood bases for rural communities.
- (a) 1 only
- (b) 1 and 2
- (c) 2 and 3
- (d) 3 only
Show the answer and explanation
Answer: (d) 3 only
Only 3 names what mangroves really do: a bio-shield plus livelihoods.
Statement by statement
1. ✗ WRONG — no freshwater store, and paddy means clearing them Mangroves do cut wave and tidal energy. But they live in salty water and do not store freshwater, and turning them into paddy destroys the very buffer we want. A half-true start with a wrong ending makes the statement wrong.
2. ✗ WRONG — the roots are salt-TOLERANT Mangrove roots are built to handle salt: they filter it out at the root, some species push it out through leaf glands, and breathing roots (pneumatophores) poke out of the mud. Clearing mangroves for shrimp and fish ponds is one of the biggest causes of their loss, so it can’t be a reason to protect them.
3. ✓ CORRECT — shield + livelihood A study of the 1999 Odisha super cyclone found fewer deaths in villages behind wider mangrove belts (Kendrapara, near Bhitarkanika). Mangroves also give fish and crab nurseries, honey (Sundarbans), fodder and fuelwood.
The idea
Mangroves are trees built for salty, waterlogged, tide-washed mud. Their tangled roots slow down waves and trap silt. That gives a coast a living wall which also grows upward as the sea rises.
Storm surge reaches the coast → Dense trunks and roots slow the water → Wave energy drops → Villages behind are less damaged → The same trees shelter fish and crabs for local people
Why the others are wrong
(a) Statement 1 ends in paddy conversion, which destroys mangroves.
(b) Both 1 and 2 are wrong: no freshwater storage, and the roots are salt-tolerant.
(c) Statement 2 is wrong, because the roots are salt-tolerant and aquaculture conversion kills mangroves.
The trap
Statements 1 and 2 open with a true-sounding fact (they reduce tidal energy, the roots filter seawater) and end in a land use that destroys mangroves. Read every sentence to the end.
Also know
India has about 4,990 km² of mangroves (ISFR), and over 40% of it is in West Bengal’s Sundarbans. The MISHTI scheme (2023) plants new mangroves along the coast.
🔒 Mangroves = bio-shield + livelihood. Salt-tolerant, not salt-sensitive. Paddy or aquaculture conversion destroys them.