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UPSC Prelims 2010 · Agriculture · Soils
When you travel in certain parts of India, you will notice red soil. What is the main reason for this color?
- (a) Abundance of magnesium
- (b) Accumulated humus
- (c) Presence of ferric oxides
- (d) Abundance of phosphates
Show the answer and explanation
Answer: (c) Presence of ferric oxides
Iron oxides (ferric oxide) give red soil its colour; hydrated, it turns yellow.
Why the others are wrong
(a) Magnesium doesn’t give red colour.
(b) Humus makes soil dark, not red.
(d) Red soils are actually poor in phosphate.
The trap
None.
🔒 Red soil: iron oxide, poor in N, P, humus; Tamil Nadu, Karnataka, Odisha, Chhattisgarh.