Prelims 2011 · archive
MediumThe 2004 Tsunami made people realize that mangroves can serve as a reliable safety hedge against coastal calamities. How do mangroves function as a safety hedge?
Answer & explanation
Answer: (d) The mangrove trees do not get uprooted by storms and tides because of their extensive roots.
Mangroves protect the coast physically. Their tangled, extensive roots hold the trees firmly in place during storms and tides. The standing root-and-branch thicket then absorbs the force of incoming waves. Only option (d) describes this mechanism. The other options describe a buffer zone, post-disaster products or shelter, none of which is how mangroves act as a hedge.
- ✓ (d) Extensive, anchoring roots let mangroves stay standing in storms and tides. That standing thicket of roots and branches reduces wave height and energy. Trees protect only as long as they are not uprooted or snapped; uprooted trees become destructive debris.
- ✗ (a) Mangroves do not work by creating an empty zone between people and the sea. They protect by absorbing wave force, whether or not anyone lives behind them.
- ✗ (b) Food and medicines are useful mangrove products, but they help only after a disaster. They do not reduce the damage of a cyclone or tsunami.
- ✗ (c) Mangroves do not protect by acting as tall shelters for people. Protection comes from their roots and branches at and near water level, which break the waves.
Remember · Mangroves are natural bio-shields. Their stilt and prop roots anchor the trees and absorb wave energy, blunting storm and tsunami waves, though an exceptionally large tsunami can still overwhelm them.
📘 Read it in NCERT: Class 11 Fundamentals of Physical Geography, Ch 6 (practise this chapter)
Sources
- NCERT Class 11 · Fundamentals of Physical Geography, Chapter 6 “Then come the barriers, beaches, beach dunes and mangroves, if any, to absorb the destructive force of storm and tsunami waves.”
- UNESCO-IOC Tsunami Programme: Mangroves, nature's shield against coastal hazards ↗ “When swell waves pass through mangrove forests, the tangled, above-ground roots and branches of the trees reduce wave height and energy.”
- FAO: The role of coastal forests and trees in tsunami protection (Ch. 6 of the post-tsunami mangrove volume) ↗ “Trees are thus effective as long as they are not uprooted or snapped, in which case they form debris that may destroy human lives and property.”
Question: UPSC Civil Services (Preliminary) 2011, General Studies paper. Explanation: Minimalist IAS, checked 25 Oct 2026 (how we verify). ·