Soils of India — Set 4
Geography · भारत की मिट्टी · Questions 31–40 of 50
Which is the second most common soil group in India after Alluvial soil?
Correct Answer: B. Red Soil
• **Red soil** = second largest soil group in India after alluvial, covering ~18% of the country, in Tamil Nadu, Karnataka, and Odisha. • **~18% of India's area** — red soil's significant coverage making it the second most extensive soil type. • 💡 Wrong-option analysis: Black soil: covers ~15%, third after alluvial and red; Laterite soil: smaller area, high-rainfall zones; Arid soil: western Rajasthan desert, smaller coverage.
Soil erosion caused by the removal of a uniform thin layer of soil by water is called?
Correct Answer: B. Sheet Erosion
• **Sheet Erosion** = uniform removal of a thin top layer of soil by rainwater over a large area, often unnoticed but highly damaging. • **Most fertile layer removed** — sheet erosion removes the nutrient-rich topsoil, reducing agricultural productivity significantly. • 💡 Wrong-option analysis: Gully Erosion: deep channel cutting by concentrated water flow; Rill Erosion: small channel formation, less severe than gully; Wind Erosion: removal by wind, not water, common in arid areas.
Which soil is mostly found in the Rann of Kutch and Sunderban areas?
Correct Answer: D. Saline Soil
• **Saline soil in Rann of Kutch and Sunderbans** = high sodium chloride due to seawater influence in both the tidal marshes of Sunderbans and the salt flats of Rann of Kutch. • **Seawater influence** — the primary reason for the high salinity in both these coastal/marshy regions. • 💡 Wrong-option analysis: Laterite soil: found on Western/Eastern Ghats summits, not Rann/Sunderbans; Black soil: Deccan Trap volcanic origin, not coastal areas; Desert soil: dry sandy Rajasthan, not these coastal marshy regions.
In which state is the laterite soil found most extensively?
Correct Answer: B. Kerala
• **Kerala** = has the most extensive laterite soil coverage due to the state's heavy rainfall and high temperature promoting intense leaching. • **Used for brick making** — laterite's hardening property when dry makes it a popular construction material in southern India. • 💡 Wrong-option analysis: Uttar Pradesh: alluvial soil state, no laterite; Rajasthan: arid/desert soils, no laterite; Punjab: alluvial Indo-Gangetic plains, no laterite.
The term 'Reh' is associated with which type of soil in India?
Correct Answer: D. Saline-Alkaline Soil
• **Reh/Kallar = Saline-Alkaline soil** = white efflorescent salt crust on the surface of saline-alkaline soils in semi-arid areas with poor drainage. • **White salt crust on surface** — the distinctive visual appearance of Reh, like white ash, indicating land rendered unfit for crops. • 💡 Wrong-option analysis: Alluvial soil: fertile, no salt crust; Mountain soil: forest-based, no salinity; Black soil: calcium/magnesium-rich but no Reh formation; that is Deccan plateau soil.
Which mineral is Black Soil notably rich in?
Correct Answer: B. Iron and Lime
• **Black soil rich in Iron and Lime** = also rich in calcium, potassium, and magnesium from its basaltic parent rock, but deficient in nitrogen, phosphorus, and organic matter. • **Basaltic rock parent material** — the volcanic basalt of the Deccan Trap that provides black soil's unique mineral composition. • 💡 Wrong-option analysis: Humus: black soil is actually deficient in organic matter/humus; Nitrogen: black soil is deficient in nitrogen; Phosphorus: black soil is also deficient in phosphorus.
The fertile soil called 'Tarai' is found in which region?
Correct Answer: A. Foothills of Himalayas
• **Tarai soil at Himalayan foothills** = marshy and fertile alluvial belt at the base of Himalayas, now cleared for sugarcane and paddy cultivation. • **Sugarcane and paddy cultivation** — the two major crops grown in the productive Tarai alluvial belt. • 💡 Wrong-option analysis: Coastal Plains: alluvial but not called Tarai; Deccan Plateau: black/red soil, not Tarai; Thar Desert: arid sandy soil, opposite of fertile Tarai.
Which color is the Laterite soil usually?
Correct Answer: C. Reddish
• **Reddish colour** = laterite soil's characteristic colour due to iron oxide content; name 'Laterite' comes from Latin 'Later' meaning brick. • **Extremely hard when dry** — laterite becomes stone-hard when dry, which is why it is used as building bricks in southern India. • 💡 Wrong-option analysis: Gray: mountain/forest soil appearance; Deep Black: black/cotton soil colour; White: saline soil (Reh) surface appearance.
Which of the following describes 'Desert Soil' texture?
Correct Answer: D. Sandy
• **Sandy texture** = desert/arid soil is generally sandy with high salt content and low water-holding capacity. • **High salt + low water retention** — the two key limitations of arid soil that restrict crop growth without irrigation. • 💡 Wrong-option analysis: Loamy: describes alluvial/forest soils; Silty: fine particle soil of river deposits; Clayey: describes black soil's high moisture-retaining heavy texture.
Which soil type is most prevalent in the Indo-Gangetic Plains?
Correct Answer: A. Alluvial Soil
• **Alluvial soil in Indo-Gangetic Plains** = the world's largest tract of alluvial soil, brought by Himalayan rivers, making the region India's 'Granary'. • **World's largest alluvial tract** — the Indo-Gangetic plain's global distinction as the most extensive alluvial deposit. • 💡 Wrong-option analysis: Red soil: found in peninsular/Deccan India; Black soil: Deccan Trap volcanic region; Laterite soil: Western/Eastern Ghats summits, not the plains.