Soil Formation

Question 1

What are the six major factors affecting soil formation?

Answer 1

1. Nature of parent bedrock
2. Climatic conditions
3. Topography
4. Agents of erosion
5. Humus
6. Time

Question 2

How does nature of parent rock affect soil formation?

Answer 2

• material of the soil as well as the minerals present in it depend on parent bedrock
• clayey soil is derived from shale
• sandy soil is derived from sandstone

Question 3

How do climatic conditions affect soil formation?

Answer 3

• climatic conditions, especially temperature and precipitation affect soil formation
• greater variation in climate and more moisture accelerates soil formation by increasing the rate of weathering

Question 4

How does topography affect soil formation?

Answer 4

Weathered rock particles get accumulated more easily in flat land and gentle slopes and slides down steep slopes due to the force of gravity.

Question 5

How does humus affect soil formation?

Answer 5

Humus or dead and decaying plants and animals provide organic matter, thus increasing fertility of the soil.

Question 6

How does time affect soil formation?

Answer 6

• time gives maturity to the soil
• soil which has taken more time to form will be deeper and will have more layers than newly formed soil.

Question 7

How do agents of erosion affect soil formation?

Answer 7

• agents of erosion such as wind and water contribute to soil formation by depositing eroded materials carried by them
• eg. Fertile alluvial soil in plains carried by water and loess carried by wind

Question 8

What is the classification of soil based on color?

Answer 8

Red, black, brown, grey

Question 9

What is the classification of soil based on texture?

Answer 9

Sandy, clayey, loamy. Sandy soil contains 60% sand and clayey soil contains 60% clay