NCERT Solutions for Class 7 Science Chapter 9 Soil
Tick the most suitable answer in questions 1 and 2.
Que. In addition to the rock particles, the soil contains
- air and water
- water and plants
- minerals, organic matter, air and water
- water, air and plants
Que. The water holding capacity is the highest in
- sandy soil
- clayey soil
- loamy soil
- mixture of sand and loam
Que. Match the items in Column I with those in Column II:
Column I | Column II |
1. A home for living organisms | a. Large particles |
2. Upper layer of the soil | b. All kinds of soil |
3. Sandy soil | c. Dark in colour |
4. Middle layer of the soil | d. Small particles and packed tight |
5. Clayey soil | e. Lesser amount of humus |
Answers:- 1 – b , 2 – c , 3 – a , 4 – e , 5 – d
Que. Explain how soil is formed.
Wind, water, and climate break down rocks to form soil. This process is called weathering. The characteristics of any soil are determined by the rocks that form it and the types of vegetation that grows there.
Que. How is clayey soil useful for crops?
A clayey soil contains tiny particles packed tightly and able to hold water due to its small size. Clayey soils are rich in organic matter. Soil that is good at retaining water and rich in organic matter is good for growing crops such as wheat, gram, and paddy. Due to these characteristics, clayey soils are suitable for growing such crops.
Que. List the differences between clayey soil and sandy soil.
Clayey soil | Sandy soil |
Majority of Fine particles | Majority of large particles |
Particles are packed tightly | Particles are loosely packed. |
hold good amount of water | cannot hold water |
less aie is trapped | more air is trapped |
rich in organic matter | not rich in organic matter |
Que. Explain how soil pollution and soil erosion could be prevented.