Soils

Question 1

Define soil

Answer 1

Soil is the thin surface layer on the earth, comprising mineral particles formed by the breakdown of rocks, decayed organic material, living organism, soil water and soil atmosphere

Question 2

What forms the organic matter of the soil. Define it

Answer 2

Humus forms the organic matter of the soil. It is the decaying plant remains that is mixed with the soil.

Question 3

Do all soils have soil profile? Which soils have soil profile

Answer 3

No, all soils don’t have a soil profile..only soils formed by insitu have soil profile e.g.- black soil

Question 4

Define soil profile

Answer 4

The soil profile is a vertical section of the soil from the surface down the the bedrock showing their individual horizons, often of different colours and textures, sometimes grading into each other, sometimes changing sharply.

Question 5

Define the A-horizon or top soil.

Answer 5

The uppermost layer of the soil which consists of all the organic matter and humus is known as the top soil or the A-Horizon.
▪︎ The upper part of the horizon contains more humus whereas the lower part contains more organic matter.

Question 6

What is the other name for B-Horizon?

Answer 6

▪︎ The other name for B- Horizon is sub-soil.
▪︎ it consists weather rock materials, sand, silt and clay.
▪︎ also known as zone of illuviation
▪︎ upper part - transitional zone
▪︎ lower part - colloids

Question 7

What are the 5 types soil can be divided into depending upon their texture?

Answer 7

1] Clay - 45% silt, 45% clay and 10% sand

2] Clay loam: 25% Clay, 42% silt and 33% sand

3] loam - 18% Clay, 42% silt and 40% sand

4] silt - 13% Clay, 82% silt and 5% sand

5] sandy loam - 11% Clay, 14%silt and 75% sand