Soil Types, Properties and Conservation

Attempt the quiz above first, then review every question with its correct answer and a short explanation below.

1. Q1.Which is the most widespread soil group in India?

   • A.black soil
   • B.red soil
   • C.alluvial soil✓ Correct Answer
   • D.laterite soil

   Explanation: Alluvial soil covers about 40 per cent of India, mainly in the Northern Plains.

2. Q2.Black soil is best suited for the cultivation of:

   • A.cotton✓ Correct Answer
   • B.jute
   • C.tea
   • D.rubber

   Explanation: Black soil is also called "black cotton soil" because it suits cotton.

3. Q3.The red colour of red soil is due to the presence of:

   • A.calcium carbonate
   • B.iron oxide✓ Correct Answer
   • C.aluminium silicate
   • D.organic humus

   Explanation: Iron oxide in crystalline and metamorphic rocks gives the soil its red colour.

4. Q4.Laterite soil is formed under conditions of:

   • A.very cold and dry climate
   • B.volcanic eruptions
   • C.high temperature and heavy rainfall with leaching✓ Correct Answer
   • D.glacial deposition

   Explanation: Heavy rain washes silica and nutrients away, leaving iron and aluminium compounds.

5. Q5.Arid (desert) soils in India are found mainly in:

   • A.Kerala
   • B.Rajasthan✓ Correct Answer
   • C.Assam
   • D.West Bengal

   Explanation: Western Rajasthan has sandy, low-humus arid soils.

6. Q6.Soil is formed mainly by the:

   • A.melting of glaciers only
   • B.weathering of rocks along with organic matter✓ Correct Answer
   • C.deposits from volcanoes only
   • D.tides of the sea

   Explanation: Parent rock, climate, relief, organisms and time together form soil.

7. Q7.Black soil (regur) is derived from:

   • A.basalt of the Deccan Trap✓ Correct Answer
   • B.granite of the Himalaya
   • C.river alluvium
   • D.coral limestone

   Explanation: Weathering of volcanic basalt over the Deccan Plateau forms black soil.

8. Q8.Black soil is known as "self-ploughing" because it:

   • A.is very sandy
   • B.contains no clay
   • C.is always waterlogged
   • D.develops deep cracks when dry that aerate the soil✓ Correct Answer

   Explanation: The clay swells when wet and shrinks into cracks when dry, mixing the soil.

9. Q9.Alluvial soil is generally rich in potash and lime but poor in:

   • A.nitrogen and phosphorus✓ Correct Answer
   • B.potash only
   • C.calcium only
   • D.iron only

   Explanation: Farmers add nitrogen and phosphatic fertilisers to alluvial soils.

10. Q10.Red soils are generally poor in:

    • A.nitrogen, humus and lime✓ Correct Answer
    • B.iron
    • C.sand
    • D.potash

    Explanation: Red soils are porous and need fertilisers and irrigation for good yields.

11. Q11.Peaty and marshy soils, rich in organic matter, are found in:

    • A.the Thar Desert
    • B.Kuttanad in Kerala and the Sundarbans✓ Correct Answer
    • C.the Deccan Plateau
    • D.Ladakh

    Explanation: Waterlogged, humid areas accumulate organic matter to form peaty soils.

12. Q12.Saline and alkaline soils are locally known as:

    • A.Regur and Bhangar
    • B.Khadar and Bhabar
    • C.Reh, Kallar and Usar✓ Correct Answer
    • D.Terai and Duar

    Explanation: These soils contain excess salts and are common in dry areas and canal-irrigated tracts.

13. Q13.The Indian Council of Agricultural Research (ICAR) was established in:

    • A.1905
    • B.1947
    • C.1929✓ Correct Answer
    • D.1966

    Explanation: ICAR was set up in 1929 and is headquartered in New Delhi.

14. Q14.The word "laterite" comes from the Latin word "later", meaning:

    • A.sand
    • B.salt
    • C.clay pot
    • D.brick✓ Correct Answer

    Explanation: Laterite hardens on drying and has been used as a building brick.

15. Q15.Laterite soils are suitable for crops such as:

    • A.wheat and barley
    • B.jute and sugarcane only
    • C.cashew, tea and coffee✓ Correct Answer
    • D.cotton only

    Explanation: With manure and fertiliser, laterite soils support plantation crops.

16. Q16.Forest soils are mostly found in:

    • A.the Thar Desert
    • B.the river deltas
    • C.the coastal sand dunes
    • D.hilly and mountainous areas with forest cover✓ Correct Answer

    Explanation: They are rich in humus on valley sides and acidic on high slopes.

17. Q17.The ravines of the Chambal valley are an example of:

    • A.sheet erosion
    • B.wind erosion
    • C.coastal erosion
    • D.gully erosion✓ Correct Answer

    Explanation: Running water cuts deep channels into soft soil, forming ravines called badlands.

18. Q18.The Central Soil Salinity Research Institute is located at:

    • A.Nagpur
    • B.Karnal✓ Correct Answer
    • C.Dehradun
    • D.Pusa

    Explanation: CSSRI at Karnal, Haryana works on salt-affected soils.

19. Q19.Layers of nodular limestone (kankar) commonly occur in the lower horizons of the soils of:

    • A.arid regions✓ Correct Answer
    • B.rainforests
    • C.glacial valleys
    • D.mangrove swamps

    Explanation: In arid soils, calcium carbonate accumulates as kankar layers that restrict water infiltration.

20. Q20.Which method is used to check soil erosion on hill slopes by ploughing across the slope?

    • A.shifting cultivation
    • B.monoculture
    • C.overgrazing
    • D.contour ploughing✓ Correct Answer

    Explanation: Contour ploughing slows down runoff and holds soil on slopes.