Land, Soil and Water Resources

Question 1

What is soil?

Answer 1

Soil is the loose covering of fine rock particles that covers the surface of the earth.

Question 2

What does soil consist of?

Answer 2

It consists of weathered particles of rocks brought down by agents of erosion (water, wind, glaciers). It also consists of decaying organic matter and minerals.

Question 3

What is “fertility of soil”?

Answer 3

Fertility of soil refers to its ability to produce vigorous growth in plants.

Question 4

What determines the fertility of soil?

Answer 4

The right mix of minerals and organic matter, and the ability to retain the correct amount of moisture determines the fertility of soil.

Question 5

How long does it take for soil to form?

Answer 5

The time taken for soil to form can range from 200 to several thousands of years.

Question 6

What are soil horizons?

Answer 6

The various layers of soil are known as soil horizons.

Question 7

What is soil profile?

Answer 7

The manner in which soil horizons are arranged is called soil profile. The soil profile is different in different places.

Question 8

What are the main layers of soil?

Answer 8

Topsoil (A)
Subsoil (B)
Parent Material (C)
Bedrock (R/D)

Question 9

Describe topsoil.

Answer 9

Topsoil is dark in colour, has fine texture, a high content of organic matter/humus and is vital for plant growth.

Question 10

Describe subsoil.

Answer 10

Subsoil is the layer below topsoil; it consists of sand, silt and clay but has only minor amounts of organic matter.

Question 11

Describe parent material.

Answer 11

The parent material consists of unconsolidated rock material from which layers A and B are formed. This layer has no humus or soil structures.

Question 12

Describe bedrock.

Answer 12

Bedrock lies below the C horizon and consists of soild rock.

Question 13

What is the ICAR?

Answer 13

ICAR is the Indian Council of Agricultural Research.

Question 14

What is alluvial soil?

Answer 14

Rich and fertile soil formed by the depositional action of rivers. Rivers transport eroded material from their higher reaches and deposit this material on their banks as they reach the plains.

Question 15

Where is alluvial soil found in India?

Answer 15

Indo-Gangetic Plains and deltaic regions of the peninsular belt. It covers almost 24% of India’s land area.

Question 16

What is black soil also known as? Why does it develop wide cracks during summer?

Answer 16

Regur soil or cotton soil. The deep and clayey soil swells when wet and contracts when dry. Therefore it develops wide cracks during summer.

Question 17

What is black soil used for?

Answer 17

It is ideal for the growth of cotton. It is also good for cultivation of cereals, pulses, oil seeds, citrus fruits and vegetables.

Question 18

Where is black soil found in India?

Answer 18

In the basaltic Deccan Plateau in the states of Maharashtra, Madhya Pradesh, parts of Gujarat and Karnataka, Telengana, Tamil Nadu, Andhra Pradesh, Uttar Pradesh and Rajasthan.

Question 19

“Red soil is sandy and red in colour” True/False? Why?

Answer 19

True. Red soil is sandy and red in colour, and the redness is due to the presence of iron oxides.

Question 20

Is red soil fertile? Which crops is it suitable for?

Answer 20

Red soil is usually fertile in the lowlands, but in the dry uplands they are less fertile. Red soil is suitable for growth of cotton, millets, onions, potatoes and wheat.

Question 21

Where is red soil found in India?

Answer 21

In the periphery of black soil regions - Odisha, Madhya Pradesh, Kerala, Andhra Pradesh, Telangana and Tamil Nadu.

Question 22

How is laterite soil formed?

Answer 22

Laterite soil is formed due to intense leaching (water washes out soil nutrients) in areas with heavy rainfall.

Question 23

Is laterite soil naturally fertile? Why?

Answer 23

Laterite soil is not naturally fertile since the topsoil and humus is washed away by heavy rainfall. To make this soil cultivable it has to be treated with fertilisers.

Question 24

What are the uses of laterite soil?

Answer 24

Growing of jute, millets and fodder crops etc. It is also used in brickmaking.

Question 25

Where is laterite soil found in India?

Answer 25

Coastal Maharashtra, Kerala, Karnataka, Odisha, Tamil Nadu and West Bengal.

Question 26

Describe arid and sandy soil.

Answer 26

Arid and sandy soil is found in the dry regions. The colour varies from dark shades of reddish brown to pastel brown. It has very low moisture and humus content as it is found in the dry deserts.

Question 27

Can arid and sandy soil be made cultivable? Where is it found in India?

Answer 27

Arid and sandy soil can be made cultivable with the sufficient irrigation. It is found in Western Rajasthan in India.

Question 28

Describe peaty and forest soil.

Answer 28

Peaty and forest soil is found in regions of dense vegetation. This soil is rich in humus as the organic matter that accumulates in forests decomposes to provide the same.

Question 29

Where is peaty and forest soil found in India?

Answer 29

Forests of Jharkhand, Bihar, Uttaranchal and evergreen forests of Western Ghats.

Question 30

What is soil erosion and soil degradation.

Answer 30

Soil erosion is the removal of topsoil. If unchecked it can lead to the depletion of soil or soil degradation.

Question 31

What is mulching?

Answer 31

Bare ground between plants is covered with a layer of organic matter (straw/peat) to prevent loss of moisture from soil. The process of conserving soil by retaining moisture in soil is mulching.

Question 32

What is contour bunding?

Answer 32

On hill sides, stones are used to build barriers across the slope following contours. Contours are imaginary lines connecting places that lie at the same altitude. Trenches are made in front of the barriers to collect water.

Question 33

What is plugging?

Answer 33

Rocks are piled up to slow down the flow of water. This prevents erosion by plugging the gullies to prevent soil loss.

Question 34

What is terrace farming?

Answer 34

Terraces are made on steep slopes so that flat surfaces are available to grow crops. Terraces reduce run-off and soil erosion. Method of conserving soil+utlilising hill slopes is terrace farming.

Question 35

Define intercropping.

Answer 35

Intercropping - Growing different crops in alternate rows and sown at different times to protect soil from rain wash.

Question 36

Define crop rotation.

Answer 36

Crop Rotation - Growing different crops in same field one after the other to conserve soil.

Question 37

What are shelter belts?

Answer 37

In coastal and dry regions, where winds of high speed can blow away top soil, rows of trees are planted around farms. These check the wind, prevent soil erosion and act as shelter belts.

Question 38

What are the other methods to prevent soil erosion?

Answer 38

Afforestation, increased use of organic manures, sprinkler and drip irrigation in place of flood irrigation can help prevent soil erosion.

Question 39

Why do large parts of our country suffer from water scarcity?

Answer 39

This is because water resources in India are unequally distributed both seasonally and spatially.

Question 40

The rivers of the Deccan and the south are __________ rivers.

Answer 40

The rivers of the Deccan and the south are seasonal rivers. They flood during the monsoons and have hardly any water during the hot summer months.

Question 41

Why were multi-purpose projects started by Indian government?

Answer 41

To control annual summer floods of northern rivers and to put the water to better use, multi-purpose projects like dams were built on rivers.

Question 42

Which purposes are served by dams?

Answer 42

flood control
providing water for irrigation
generation of hydroelectricity
providing drinking water and recreation

Question 43

Mention 5 multi-purpose projects in India.

Answer 43

Bhakra-Nangal Project, Damodar Valley Project, Hirakud Project, Nagarjunasagar Project and Narmada Valley Project.

Question 44

Main sources of irrigation in India are?

Answer 44

irrigation canals, wells, tanks and tubewells