RBSE Class 11 Geography Important Questions Chapter 6 Soils

Rajasthan Board RBSE Class 11 Geography Important Questions Chapter 6 Soils Important Questions and Answers. 

RBSE Class 11 Geography Important Questions Chapter 6 Soils

Multiple Choice Questions

1. Which soil is called Regur?
(A) Red 
(B) Laterite
(C) Black 
(D) Alluvial
Answer:
(C) Black 

2. Which layer of soils has mostly organic matter?
(A) ‘A’ Horizon 
(B) B’ Horizon
(C) ‘C’ Horizon 
(D) Rocks
Answer:
(A) ‘A’ Horizon 

3. ‘Self ploughing’ soil is .
(A) Alluvial 
(B) Blacks
(C) Laterite 
(D) Red
Answer:
(B) Blacks

4. What is the meaning of Laterite word?
(A) Clay 
(B) Brick
(C) Sediments 
(D) Potash
Answer:
(B) Brick

5. Which valley has most of Ravines?
(A) Ganga 
(B) Chambal
(C) Assam 
(D) Narmada
Answer:
(B) Chambal

6. What is the main cause of soil erosion in shivaliks?
(A) Rainfall 
(B) Over Grazing
(C) Deforestation 
(D) River Dams
Answer:
(B) Over Grazing

7. Which soil has more expansion in Maharastra states?
(A) Black soil 
(B) Red soil 
(C) Alluvial soil 
(D) Laterite soils
Answer:
(A) Black soil 

8. When was the first soil survey in India?
(A) 1936 
(B) 1946
(C) 1956 
(D) 1966
Answer:
(C) 1956 

9. The new alluvium soil is called.
(A) Lowland 
(B) Khadar
(C) Bhabar 
(D) Banger
Answer:
(B) Khadar

10. What is self ploughing soil?
(A) Alluvial
(B) Black
(C) Laterite 
(D) Red
Answer:
(B) Black

Very Short Answer Type Questions

Question 1. 
Name the four main elements found in soils.
Answer: 
Silica, clay, chalk and humus.

Question 2. 
What is the function of clay in soils? 
Answer:
It absorbs water.

Question 3. 
Name the three layers (horizons) of soils. 
Answer: 

• A Horizon-Top soil
• B Horizon-Sub-soil
• C Horizon-Mantle.

Question 4. 
Define the term Soil.
Answer: 
Soil is a thin layer of loose material.

Question 5. 
State the factors on which the formation of soils depend.
Answer: 

• Parent material
• Topography
• Climate.

Question 6. 
Name three broad regional divisions of soils in India.
Answer: 

• Soils of the Peninsula
• Soils of the Northern plains
• Soils of the Himalayas.

Question 7. 
Which is the most widespread soil in India?
Answer: 
Alluvial soils.

Question 8. 
Name two main types of alluvial soils found in Northern India.
Answer: 
Khadar and Bangar soils.

Question 9. 
Which soil is spread over large area of northern plains?
Answer: 
Alluvial soils.

Question 10. 
Which soils are found on the periphery of Deccan plateau?
Answer: 
Red soils.

Question 11. 
Which soil is most widespread over Peninsular India?
Answer: 
Red soil.

Question 12. 
Name two states where red soils are mostly found.
Answer: 
Tamil Nadu and Chhattisgarh.

Question 13. 
Name two states where black soils are found.
Answer: 
Maharasthra and Madhya Pradesh.

Question 14. 
Name the crop for which black soil is best suited.
Answer: 
Cotton.

Question 15. 
In which type of climate, are laterite soils formed?
Answer: 
Tropical monsoon climate.

Question 16. 
State the two types of laterite soils.
Answer: 
Upland laterites and lowland laterites.

Question 17. 
Name an area in India where desert soils are found.
Answer: 
Thar Desert (Rajasthan and Sind).

Question 18. 
What are Chos?
Answer: 
Chos are seasonal streams in the foothills of Shiwaliks.

Short Answer Type Questions

Question 1. 
What is the process of Pedogenesis?
Answer: 
Soil formation is a complex process. Soil is formed under specific natural conditions. All the physical, chemical, biological and cultural elements of the environment act and react together to form the soils. Soil is the end product of these processes. The process of soil formation is known as process of pedogenesis.

Question 2. 
What is Parent Material?
Answer: 
All the materials derived from the weathering and erosion of the exposed rocks are called parent material. Parent material is generally composed of minerals. Soils are formed by these parent materials. The colour, texture, fertility of the soil depend upon parent material.

Question 3. 
What is Soil? How is it formed?
Answer: 
The loose and unconsolidated material which forms the upper layer of the crust is called soil. It is found in layers or horizons. Its thickness varies from some cms. to metres. It consists of many mineral and organic particles, humus, bacteria, etc. Soil formation is a slow process. Soil is formed through the chemical and mechanical weathering of rock cover. Parent materials derived from rock cover and humus together lead to soil formation. Soil is the end product of the physical, chemical, biological and cultural factors which act and react together.

Question 4 
What are the major factors in the formation of Soil?  
Answer: 
The formation of soil depends upon many factors. The major factors are :

1. Parent Material.
2. Climate.
3. Surface features of relief.
4. Slope of the land.
5. Natural vegetation.

Question 5. 
Describe the formation of Laterite soils, giving two reasons in support of your answer. Name two areas where such soils may be found.
Answer: 
Laterite soils. Laterite soils are found on the highland areas of the plateau. These are found in Karnataka, Kerala, Tamil Nadu and hilly regions of Assam, Rajamahal hills and Chhota Nagpur plateau. Due to monsoonal climate (wet and dry seasons alternately occurring), there is the leaching of soils. It washes away the silica current in soils. These are shallow, acidic and less fertile soils. The lowland laterite soils are useful for cultivation of foodgrains and other crops. The upland laterites are thin, coarse and infertile. These soils are poor in nitrogen and lime, but rich in iron. So these are suitable for plantation of crops like tea, rubber, coffee, etc.

Question 6. 
What are the characteristics of Alluvial Soils?
Answer: 

1. Alluvial soils are deposited by rivers.
2. These soils are limited to river basins and plains.
3. These are very fertile soils.
4. It consists of fine grained clay and sand.
5. These soils are rich in potash, but poor in phosphorus.
6. These are generally deep soils.

Question 7. 
What is Contour Ploughing? How can; we guard against the danger of Soil Exhaustion? 
Answer: 
Contour Ploughing. In hilly slopes, terraced farming is practised along the contour lines. These terraced fields break the flow of surface run off. Along steep slopes, small bunds are constructed on a contour to act as a barrier. Contour ploughing helps in protecting soil.
The following methods are adopted to guard against soil exhaustion :

1. Afforestation and Reforestation.
2. Controlled grazing.
3. Terraced ploughing.
4. Contour bunding.
5. Rotation of crops.

Question 8. 
Which type of soils are formed as a result of wide diffusions of iron in the rocks? Explain two important characteristics of these soils of India.
Answer: 
Red Soils are formed as a result of wide diffusion of iron in the rocks. Characteristics of Red Soils. These soils are found in Tamil Nadu, Karnataka, Andhra Pradesh and areas on periphery of Deccan Plateau. These soils have been formed due to decomposition of underlying igneous rocks. The red colour of these soils is due to oxidation and diffusion of iron in hard crystalline rocks. These are given to the cultivation of millets, pulses, linseed, tobacco etc. These soils cover the largest area in Peninsular India. These soils are poor in lime, nitrogen and humus. Fertilizers are added to make these fertile.

Question 9. 
What methods should be used to improve the fertility of the soils?
Answer: 
The following methods should be used to improve the fertility of the soils :

1. Methods should be adopted to check soil erosion.
2. Manures and chemical fertilizers should be used to maintain the fertility of soils.
3. Crop rotation should be practised.
4. Scientific methods of cultivation be used.
5. Land should be kept fallow to retain its fertility.
6. Suitable combination of crops should be cultivated.

Question 10. 
Explain the importance of soils.
Answer: 
Many human and economic activities depend upon soils. All our food comes directly or indirectly from soils. Livestock farming depends upon raising of grass on different soils. Soils have affected the march of civilisations. Ancient civilisations developed in fertile river valleys. Fertile soils attract human settlements. Density of population depends upon soil fertility and productivity.

Question 11. 
Name any five methods to check Soil Erosion.
Answer: 
The following methods are adopted to guard against soil erosion:

1. Afforestation and Re-afforestation.
2. Controlled grazing.
3. Terraced ploughing.
4. Contour bunding.
5. Rotation of crops.

Question 12. 
What are the characteristics of Laterite Soils? Name one region where it is found.
Answer: 

1. The laterite soils are of brick colour.
2. These are shallow, acidic and less fertile.
3. These are less fertile due to leaching of soil.
4. These are poor in nitrogen, potash but rich in iron.
5. These are found in Tamil Nadu.

Question 13. 
What are Ravines? Where are these found in India?
Answer: 
Due to gully erosion, channels form deep gullies. These deep troughs are called ravines. These are found in Chambal valley. 

Comparison Questions

Question 1. 
Compare Black soils and Red soils of India.
Answer:
table 1

Essay Type Questions

Question 1. 
What is soil erosion? Explain the formation and distribution of Ravine in India?
Answer: 
SOIL EROSION
Causes of soil erosion-So long a cause of soil erosion balance exists between the processes of soil formation and soil erosion, there is no problem. When the balance is disturbed, the soil erosion becomes a menace. Indiscriminate felling of trees, careless overgrazing of pasture lands, unscientific drainage operations and improper land use are some of the important causes which upset this balance. Soil erosion has been a problem in West Bengal, Uttar Pradesh, Madhya Pradesh, Maharashtra.

Tamil Nadu, Karnataka, Delhi, Rajasthan and many other parts of India. Excessive grazing by cattle on the slopes of hills cause rapid soil erosion. Potato cultivation in Meghalaya and in the Nilgiri hills, clearing of forests in the Himalayas and on the Western Ghats, and jhuming by the tribal population in different parts of the country have resulted in considerable depletion of the soils.
Ravines. 
(1) Ravines are wide spread in the Chambal basin. They cover over 6 lakh hectares of land in Gwalior, Morena and Bhind districts of Madhya Pradesh, and Agra, Etawah and Jalaun districts of Uttar Pradesh. 

(2) In Tamil Nadu, ravines are common in South Arcot, North Arcot, Kanniyakumari, Tiruchirapalli, Chingleput, Salem and Coimbatore districts. 

(3) In West Bengal numerous gullies and ravines exist in the upper catchment areas of the Kangsabati river in Purulia district. The country is losing about 8,000 hectares to ravines every year.

Effects of Soil Erosion. 

(1) It is estimated that over 80,000 hectares of cultivated land of India have already been lost and a much larger area is rendered less productive by soil erosion every year. 

(2) Soil erosion is a national menace for the Indian agriculture and its bad effects are seen in other spheres also. 

(3) Eroded materials are carried down to rivers and they lower down their carrying capacity, and cause frequent floods and damage to agricultural lands. 

(4) The bed of the Kaveri river in Tiruchirapalli and Tanjavur districts of Tamil Nadu, for example, has gradually risen and many of the old irrigation sluices and drainage inlets have got blocked. The shallowing of the Brahmaputra causes flood every year. 

(5) Silting of tanks is another serious consequence of soil erosion. A large number of tanks in different parts of the country get silted every year.
Types of Soil Erosion. The two most active agents of soil erosion in India are wind and running water. Wind erosion is common in arid and semi- arid areas of Gujarat, Rajasthan and Haryana. Light soils are more susceptible to wind erosion than heavier soils. Sands removed by wind spread over adjoining cultivated lands and destroy their fertility. Water erosion which is more serious and occurs extensively in different parts of India takes place mainly in the form of sheet and gully erosion. Sheet erosion takes place on level lands after heavy shower and the soil removal is not easily noticeable. Gully erosion is common on steep slopes. Gullies deepen with rainfall, cut the agricultural lands into small fragments and make them unfit for cultivation. 

Several factors contribute to soil deterioration. For example, when the forests are cut, the supply of humus to the soil stops, and the capacity of running water to remove its top layer grows. If drainage system is disturbed, water logging or loss of soil moisture takes place; and if it is overused, it loses its fertility. The removal of the soil by running water in wet areas and wind in dry areas is referred to as soil erosion and the removal of its organic and mineral content is referred to as soil exhaustion. Soil degradation results from its misuse.

Question 2. 
What is Soil Erosion? In what different ways does it occur?
Answer: 
Soil Erosion. It is the destruction and removal of top soil by running water, wind, etc. Soil erosion has become a serious problem in many areas. Soil formation is a slow process and takes thousands of years to develop soil, but it may be removed in a matter of a few years. Soil erosion results from the following causes :
Causes of Soil Erosion :
(1) Steep slopes. Steep slopes affect the rapidity of running water. On steep slopes, intensity of soil- erosion increases.

(2) Torrential rainfall. Heavy rainfall loosens the soil particles and scoops out the soil forming gullies and ravines. This gives rise to a dissected surface called badland as in Chambal Valley of India.

(3) Strong winds. Winds and dust storms blow away soil in dry areas. This process is known as deflation.

(4) Over-grazing. Due to over-grazing, the vegetation becomes too thin to protect the soil. Rain and wind can easily erode the loose soil.

(5) Over-cropping. Crop rotation maintains soil fertility. But over-cropping and shifting cultivation renders soil infertile.

(6) Deforestation. Deforestation means the removal of forest cover and it exposes the area to soil-erosion. Reckless cutting of trees has resulted in soil erosion by chos along the Siwalik hills. Human misuse of the land through wrong farming practices, deforestation, etc. leads to the removal of soil cover.

Source Based Questions

1. Read the following paragraph and answer the questions given below:
Soil is the loose material which forms the layer of mantle rock. India is primarily an agricultural country. The success of agriculture depends upon the fertility of soils. The soils of India are classified into three main groups depending upon the rock cover and climatic conditions. Black soils are mainly found over the Deccan Lava tract including Maharashtra, Madhya Pradesh, Gujarat and Andhra Pradesh. These soils are found in river valleys of Narmada, Tapti, Godavari and Krishna.

These soils have been formed due to weathering of lava rocks. These soils cover an area of about 5 lakh sq. km. These soils are rich in lime, iron, magnesia and alumina. But these lack in phosphorus, nitrogen and organic matter. These are also called Regur soils. These soils are most suitable for cotton cultivation and are most known as Black cotton soils. These soils are compared with Chernozem soils of Russia and Prairie soils of U.S.A. These soils can hold water. These soils are suitable for rice, wheat, jowar, sugarcane, tobacco and oil seeds.

(i) Regur soil is another name for the
(a) Saline soil 
(b) Arid soil
(c) Black soil 
(d) Laterite soil
Answer: 
(c) Black soil

(ii) In how many groups Indian soils can be classified according to climatic conditions?
(a) 2 
(b) 3
(c) 4 
(d) 5
Answer: 
(b) 3

(iii) Self-ploughing soil is-
(a) Alluvial 
(b) Black
(c) Laterite 
(d) Red
Answer: 
(b) Black

(iv) How much area is covered by black soils?
(a) 3 lakh sq. km 
(b) 4 lakh sq.km
(c) 5 lakh sq. km 
(d) None of these
Answer: 
(c) 5 lakh sq. km
 
2. Read the following paragraph and answer the questions given below:
Alluvial soils have been deposited by the rivers in river valleys of Mahanadi, Godavari, Krishna and their deltas. These are deep and fertile soils. These are dark soils. These soils are suitable for cultivation of jute, rice, sugarcane, etc. These soils are the most widespread soils, covering an area of 8 lakh sQuestion km. from Punjab to Assam. These cover about 43.7% area of India. These soils have been deposited by sediments brought by rivers. These are found in river, flood plains and coastal areas. These are deep soils rich in potash, but poor in nitrogen. These are of two types- Khadar (the new alluvium) and Bangar (a system of older alluvium).

(i) Which one of the following is the most widespread and most productive category of soil?
(a) Alluvial soil 
(b) Laterite soil
(c) Black soil 
(d) Forest soil
Answer: 
(a) Alluvial soil

(ii) The extent of which soil expands from Punjab to Assam?
(a) Black soil 
(b) Red soil
(c) Alluvial soil 
(d) Laterite soil
Answer: 
(c) Alluvial soil

(iii) How many types of alluvial soils are there in India?
(a) 2 
(b) 3
(c) 4 
(d) 5
Answer: 
(a) 2 

HOTS QUESTIONS 

Question 1
Which types of soils are derived from Deccan Lavas? Describe three important characteristics of these soils.
Answer: 
Black soils or Regur soils are derived from Deccan Lavas. These are called cotton soils also. The three important characteristic of these soils are : Black soils are mainly found over the Deccan Lava tract including Maharashtra, Madhya Pradesh, Gujarat and Andhra Pradesh. These soils have been formed due to weathering of lava rocks. These soils cover an area of about 5 lakh sQuestion km. These soils are rich in lime, iron, magnesia and alumina. But these lack in phosphorous, nitrogen and organic matter. These are called ‘Regur Soils’. These soils are most suitable for cotton cultivation and are known as ‘Black Cotton Soils’.  

SELF EVALUATION TEST

1. Name the layers of soils.
2. Which is the most widespread soil in India? 
3. Name two states where black soil is found. 
4. What are Chos? 
5. How is soil formed? 
6. Whate is Contour Ploughing? 
7. What is soil erosion? 
8. What are characteristics of Alluvial Soils? 
9. State methods to check soil erosion. 
10. How are Ravines formed?