NCERT Solutions for Class 7 Science Chapter 9 Soil
You will find NCERT Solutions for Class 7 Science Chapter 9 Soil will help every students in passing exams with flying colours. These are helpful in building a great foundation of concepts and make easy for the students to understand basics. You develop the ability to effectively respond to the high end questions that you’re confronted with. It will allow students to cover the entire syllabus effectively without any frustration.
Detailed explanation provided under each NCERT solutions for Class 7 Science will help in understanding the concepts better. In the examinations, you will can come up with better answers and lay out the main point effectively. Chapter 9 Soil Class 7 Science NCERT Questions and Answers is very challenging to score good marks in tests that is why we have prepared NCERT Solutions.
NCERT Solutions for Class 7 Science Chapter 9 Soil
Through these NCERT Solutions for Chapter 9 Soil Class 7 Science, students should not waste time and adopt a strategy that helps them operate and learn at maximum efficiency. These NCERT Solutions are prepared as per the accordance of latest CBSE guidelines so you can score maximum marks. It will be useful in expanding student's horizon as it cover variety of questions.
| Study Material for Class 7 Science Chapter 9 Soil |
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Page No: 105
Tick the most suitable answer in questions 1 and 2.
1. In addition to the rock particles, the soil contains
(i) air and water
(ii) water and plants
(iii) minerals, organic matter, air and water
(iv) water, air and plants
Answer
✓ (iii) minerals, organic matter, air and water
2. The water holding capacity is the highest in
(i) sandy soil
(ii) clayey soil
(iii) loamy soil
(iv) mixture of sand and loam
Answer
✓ (ii) clayey soil
3. Match the items in Column I with those in Column II:
| Column I | Column II |
| (i) A home for living organisms | (a) Large particles |
| (ii) Upper layer of the soil | (b) All kinds of soil |
| (iii) Sandy soil | (c) Dark in colour |
| (iv) Middle layer of the soil | (d) Small particles and packed tight |
| (v) Clayey soil | (e) Lesser amount of humus |
Answer
| Column I | Column II |
| (i) A home for living organisms | (b) All kinds of soil |
| (ii) Upper layer of the soil | (c) Dark in colour |
| (iii) Sandy soil | (a) Large particles |
| (iv) Middle layer of the soil | (e) Lesser amount of humus |
| (v) Clayey soil | (d) Small particles and packed tight |
4. Explain how soil is formed.
Answer
The soil is formed by the process of weathering in which the rocks break down by the action of wind, water and climate. It is a very slow process and big rocks get converted into soil.
5. How is clayey soil useful for crops?
Answer
Clayey soil is very useful for crops because:
(i) It has very good water retaining capacity.
(ii) This soil is rich in humus and is very fertile.
(iii) It contains useful organic minerals.
These properties of loamy soil is very suitable for growing crops.
6. List the differences between clayey soil and sandy soil.
Answer
| Clayey Soil | Loamy Soil |
| (i) It has much smaller particles. | (i) It has much larger particles. |
| (ii) It can hold good amount of water. | (ii) It cannot hold water. |
| (iii) It is fertile. | (iii) It is not fertile. |
| (iv) Air content is low. | (iv) Air get trapped between the particles. |
| (iv) Particles are tightly packed | (iv) Particles are loosely packed |
| (iv) Good for growing various crops. | (iv) Not suitable for growing crops. |
7. Sketch the cross section of soil and label the various layers.
Answer
8. Razia conducted an experiment in the field related to the rate of percolation. She observed that it took 40 min for 200 mL of water to percolate through the soil sample. Calculate the rate of percolation.
Answer
Amount of water taken = 200 mL
Time taken by water to percolate = 40 min
∴ Rate of percolation = Amount of water taken/Time taken by water to percolate
= 200 mL/40 min = 5 mL/min
Page No: 106
9. Explain how soil pollution and soil erosion could be prevented.
Answer
Steps for preventing soil pollution and soil erosion:
(i) Plantation should be encouraged because plant roots firmly bind the soil and help in preventing erosion.
(ii) Methods like crop rotation and mixed farming should be followed.
(iii) Use of organic fertilizers and manure instead of synthetic.
(iv) Pesticides and insecticides should be used in limited quantity and find natural way to prevent it.
(v) Plastic bags should b banned and it doesn't decompose and gives rise to soil pollution.
(vi) Industrial waste shouldn't be dumped directly as it kill necessary micro organisms of soil.
10. Solve the following crossword puzzle with the clues given:
2. Plantation prevents it.
5. Use should be banned to avoid soil pollution.
6. Type of soil used for making pottery.
7. Living organism in the soil.
Down
1. In desert soil erosion occurs through.
3. Clay and loam are suitable for cereals like.
4. This type of soil can hold very little water.
5. Collective name for layers of soil.
Answer
Across
2. Plantation prevents it. → Erosion
5. Use should be banned to avoid soil pollution. → Polythene
6. Type of soil used for making pottery. → Clay
7. Living organism in the soil. → Earthworm
Down
1. In desert soil erosion occurs through. → Wind
3. Clay and loam are suitable for cereals like. → Wheat
4. This type of soil can hold very little water. → Sandy
5. Collective name for layers of soil. → Profile
Go Back To NCERT Solutions for Class 7 Science
Chapter 9 Soil Class 7 Science NCERT Solutions
These Class 7 Science NCERT Solutions has been prepared by experts faculty of Studyrankers who have large experience in teaching and successfully helped students in cracking examinations with good marks. NCERT Solutions for Class 7 will help you in building basic skills through which you can prepare yourselves for exams.
Class 7 Science Chapter 9 Soil NCERT Questions and Answers - Topics
• Soil Teeming With Life
• Soil Profile
• Properties of Soil
→ Percolation rate of water in soil
• Moisture in Soil
• Absorption of Water By Soil
• Soil and Crops
Class 7 Science Chapter 9 Soil NCERT Questions and Answers - Notes
• Soil is one of the most important natural resources. It provides anchorage to the plants and supplies water and nutrients. It is the home for many organisms. Soil is essential for agriculture.
• Soil is composed of distinct layers. The rotting dead matter in the soil is called humus.
→ The soil is formed by the breaking down of rocks by the action of wind, water and climate. This process is called weathering.
→ A vertical section through different layers of the soil is called the soil profile. Each layer differs in feel (texture), colour, depth and chemical composition. These layers are referred to as horizons.
→ This layer is generally soft, porous and can retain more water. It is called the topsoil or the A-horizon.
→ The next layer has a lesser amount of humus but more of minerals. This layer is generally harder and more compact and is called the B-horizon or the middle layer.
→ The third layer is the C-horizon, which is made up of small lumps of rocks with cracks and crevices.
→ Below C-horizon, bedrock is present which is hard and difficult to dig with a spade.
• The mixture of rock particles and humus is called the soil. Living organisms, such as bacteria, plant roots and earthworm are also important parts of any soil.
→ If soil contains greater proportion of big particles it is called sandy soil.
→ If the proportion of fine particles is relatively higher, then it is called clayey soil.
→ Loamy soil is a mixture of sand, clay and another type of soil particle known as silt.
• Amount of water drained through water in unit time is known as percolation rate of water in soil. Percolation rate of water can be calculated using the formula: amount of water (mL)/percolation time (min).
• Amount of water present in soil is called moisture present in soil. The amount of moisture present in clayey soil is highest and that in sandy soil is lowest.
• Different soil absorbs different amount of water. Clayey soil absorbs the highest amount of water because of its higher water retention capacity while, sandy soil absorbs the least amount of water because of its lower water retention capacity.
• Soil is affected by wind, rainfall, temperature, light and humidity.
→ Clayey and loamy soils are both suitable for growing cereals like wheat, and gram.
→ For paddy, soils rich in clay and organic matter and having a good capacity to retain water are ideal.
→ For lentils (masoor) and other pulses, loamy soils, which drain water easily, are required. For cotton, sandy-loam or loam, which drain water easily and can hold plenty of air, are more suitable.
→ Crops such as wheat are grown in the fine clayey soils, because they are rich in humus and are very fertile.
Chapter 9 Soil Class 7 Science Questions and Answers - MCQ Questions with answers
1. Alluvial soil is found in
(a) Planes of western ghat
(b) Kuchh of Gujarat
(c) Deserts of Rajasthan
(d) Planes of north India
► (d) Planes of north India
2. Weathering is breaking down of rock by the action of:
(a) Wind
(b) Water
(c) Climate
(d) Wind, water and climate
► (d) Wind, water and climate
3. A well-developed soil profile is the result of:
(a) Physical process
(b) Chemical process
(c) Organic process
(d) All of the above
► (d) All of the above
4. Soils are classified according to their:
(a) colour and type of mineral content
(b) colour and texture
(c) texture and type of mineral content
(d) colour, texture and type of mineral content
► (b) colour and texture
5. Humus refers to the:
(a) Top most layer
(b) Bottom layer
(c) Rotting dead matter in soil
(d) None of the above
► (c) Rotting dead matter in soil
6. Soil erosion is a process of
(a) Soil formation
(b) Soil pollution
(c) Weathering
(d) Removal of top soil
► (d) Removal of top soil
7. Laterite soil is not found in
(a) Karnataka
(b) Kerala
(c) Rajasthan
(d) Tamil Nadu
► (c) Rajasthan
8. Which layer is formed of decayed organic matter?
(a) Air
(b) Humus
(c) Clay
(d) Minerals
► (b) Humus
9. Series of layer in soil profile are called
(a) Longitudinal section
(b) Transverse section
(c) Sphere
(d) Horizons
► (d) Horizons
10. Which top soil is best for growing plants?
(a) Sandy soil
(b) Clayey soil
(c) Loamy soil
(d) All of the above
► (c) Loamy soil
With the help of NCERT Solutions for Class 7 Science Chapter 9, you can figure out the latest marking scheme and prepare your answers as per the demand. Students can cross check their answers and also whether they learned it properly or not. These Class 7 Science NCERT Solutions will be quite helpful in making learning process and effortless and more effective.