Soils and Natural Vegetation of the World - Practice Test 3

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

1. Q1.The 'Campos' are tropical grasslands found in which country?

   • A.Argentina
   • B.Brazil✓ Correct Answer
   • C.Venezuela
   • D.Mexico

   Explanation: Campos are the tropical savanna grasslands located in the Brazilian Highlands.

2. Q2.Which specific soil type in Brazil is famous for coffee cultivation?

   • A.Terra Rossa
   • B.Terra Roxa✓ Correct Answer
   • C.Chernozem
   • D.Loess

   Explanation: Terra Roxa (Purple Earth) is a fertile red-purple volcanic soil in Brazil, ideal for growing coffee.

3. Q3.Permafrost (permanently frozen ground) is a characteristic feature of which biome?

   • A.Taiga
   • B.Tundra✓ Correct Answer
   • C.Alpine
   • D.Temperate Forest

   Explanation: In the Tundra biome, the subsoil remains frozen throughout the year, a condition known as permafrost.

4. Q4.Valuable hardwood trees like Mahogany, Ebony, and Rosewood are found in:

   • A.Tropical Deciduous Forests
   • B.Tropical Evergreen Forests✓ Correct Answer
   • C.Coniferous Forests
   • D.Temperate Broadleaf Forests

   Explanation: These hardwood species are typical of Tropical Evergreen Rainforests, where high rainfall supports dense growth.

5. Q5.Which soil horizon is often called the 'Zone of Eluviation' (washing out)?

   • A.Horizon O
   • B.Horizon A (or E)✓ Correct Answer
   • C.Horizon B
   • D.Horizon C

   Explanation: The E horizon (often part of A) is where minerals and organic matter are leached (washed out) downwards to the B horizon.

6. Q6.Which agricultural method is most effective in preventing soil erosion on steep hill slopes?

   • A.Strip Cropping
   • B.Terrace Farming✓ Correct Answer
   • C.Crop Rotation
   • D.Shelter Belts

   Explanation: Terrace farming creates flat steps on the slope, reducing the speed of water runoff and preventing soil erosion.

7. Q7.The 'Sahel' is a semi-arid transition zone located between which two regions?

   • A.Sahara Desert and Savanna✓ Correct Answer
   • B.Amazon Rainforest and Andes
   • C.Tundra and Taiga
   • D.Kalahari Desert and Veld

   Explanation: The Sahel extends across Africa, separating the dry Sahara Desert to the north from the humid Savannas to the south.

8. Q8.Which group of plants is famous for fixing atmospheric nitrogen in the soil?

   • A.Cacti
   • B.Legumes✓ Correct Answer
   • C.Conifers
   • D.Epiphytes

   Explanation: Leguminous plants (like peas, beans) have root nodules containing bacteria that fix nitrogen, enriching the soil.

9. Q9.Temperate Deciduous forests shed their leaves in winter primarily to protect against:

   • A.Heavy Rainfall
   • B.Freezing temperatures and water loss✓ Correct Answer
   • C.Grazing animals
   • D.Excessive sunlight

   Explanation: In temperate zones, broadleaf trees shed leaves in winter to prevent water loss (as frozen water is unavailable) and tissue damage.

10. Q10.Soil texture is determined by the relative proportions of:

    • A.Humus and Water
    • B.Sand, Silt, and Clay✓ Correct Answer
    • C.Nitrogen, Phosphorus, and Potassium
    • D.Rocks and Minerals

    Explanation: Soil texture refers to the size of the particles that make up the soil, specifically the percentage of sand, silt, and clay.

11. Q11.Which forest region is the world's largest source of softwood timber?

    • A.Tropical Rainforest
    • B.Temperate Deciduous Forest
    • C.Coniferous Forest (Taiga)✓ Correct Answer
    • D.Mediterranean Forest

    Explanation: Coniferous forests contain tall, straight trees with softwood, making them ideal for lumber, paper, and pulp industries.

12. Q12.'Fynbos' is the unique shrubland vegetation found in:

    • A.South Africa✓ Correct Answer
    • B.Australia
    • C.California
    • D.Central Asia

    Explanation: Fynbos is a belt of natural shrubland vegetation located in the Western Cape of South Africa (Mediterranean climate).

13. Q13.Andisols are soils that are primarily formed from:

    • A.River deposits
    • B.Volcanic ash and debris✓ Correct Answer
    • C.Glacial till
    • D.Decayed organic matter

    Explanation: Andisols are soils formed in volcanic ash and are characterized by high fertility and water-holding capacity.

14. Q14.What are 'Gallery Forests'?

    • A.Forests maintained for tourism
    • B.Forests growing along river banks in grasslands✓ Correct Answer
    • C.Forests on mountain tops
    • D.Underground forests

    Explanation: Gallery forests are corridors of trees growing along rivers or wetlands in landscapes that are otherwise dominated by sparse grass (savannas).

15. Q15.A soil with a pH value of 4.5 is considered:

    • A.Neutral
    • B.Strongly Alkaline
    • C.Strongly Acidic✓ Correct Answer
    • D.Slightly Alkaline

    Explanation: pH 7 is neutral. Values below 7 are acidic. A pH of 4.5 indicates strongly acidic soil, common in humid regions.

16. Q16.Humus, the organic component of soil, is formed by the decomposition of:

    • A.Rocks
    • B.Plant and animal residues✓ Correct Answer
    • C.Plastic waste
    • D.Chemical fertilizers

    Explanation: Humus is the dark organic matter that forms in soil when dead plant and animal matter decays.

17. Q17.Podzolization is a soil-forming process that typically occurs in which climate?

    • A.Hot and Dry
    • B.Cool and Humid✓ Correct Answer
    • C.Tropical Wet
    • D.Equatorial

    Explanation: Podzolization occurs in cool, humid climates (like Taiga) where acid leaching removes iron and aluminum from the topsoil.

18. Q18.In arid regions, what is the primary cause of soil salinization in agricultural lands?

    • A.Heavy Rainfall
    • B.Over-irrigation and poor drainage✓ Correct Answer
    • C.Use of organic manure
    • D.Crop rotation

    Explanation: Over-irrigation in dry areas raises the water table; as water evaporates, it leaves behind dissolved salts, making the soil saline.

19. Q19.'Lianas' are thick woody vines typically found in:

    • A.Tundra
    • B.Tropical Rainforests✓ Correct Answer
    • C.Deserts
    • D.Grasslands

    Explanation: Lianas are characteristic of tropical rainforests; they root in the soil and climb trees to reach the sunlight in the canopy.

20. Q20.The scientific study of soils is known as:

    • A.Geology
    • B.Pedology✓ Correct Answer
    • C.Petrology
    • D.Ecology

    Explanation: Pedology is the branch of science concerned with the formation, nature, ecology, and classification of soils.