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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL

UNIT: I - LAND RESOURCES CONTENT  Land as a resource, land use , land utilization patterns  Land degradation and conservation methods  Soil formation, soil types , causes of soil degradation , soil conservation

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UNIT: I - LAND RESOURCES INTRODUCTION Earth is a unique planet in our solar system. It has many favourable conditions suitable for the growth and development of humans’, animals and plants. Anything on earth that is necessary for human survival and satisfies human needs is called a resource Natural resources are the resources that we get from nature Land, soil and water are the three important natural resources. The entire system depends on these resources directly or indirectly. All these resources are finite – that is they are limited in supply. Therefore we need to utilise these resources in the best possible way, ensuring maximum benefits with minimal waste. If we overuse or misuse them, a time soon will come when life on earth will be impossible. Let us see how these resources are distributed on the surface of the earth and their pattern of use. LAND RESOURCES Land resources meet many human needs. In fact, they provide the base for life and are the building blocks for development Let us outline why land is considered such a major resource 

Land is used to build homes , transportation lines and other requirements of a human settlement

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Agriculture, forestry, animal rearing, mining industrial and other economic activities all develop on land, therefore, land yields food, raw materials and gives us a source of income

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Land provides us with many scenic spots that humans utilise for recreation and enjoyment.

Only 30 percent of the earth’s surface is land. Of this land, only a fraction is habitable by humans, the rest is made of vast deserts, dense forests and rugged mountains. The rocky slopes of the mountains , low-lying areas prone to flooding during rainy seasons, dry and sandy desert areas, regions covered by continental and mountain glaciers and thick forested

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL areas are generally sparsely populated or uninhabited . In fact 90 percent of the world’s population lives on just 30 percent of the land area. Explore some more........ 30 % of the earth’s land is occupied by 90 % of its people. Can you think just where this is? CLASSIFICATION OF LAND Land can be classified in many ways 

On the basis of relief– as plains, plateaus, and mountains

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On the basis of soil fertility – as barren and fertile land

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On the basis of development of that area – as rural and urban land

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On the basis of ownership of land – as private land and community or government land.

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On the basis of the use we put it to – arable land (i.e., land which is suitable for crop production), pasture land (land used for grazing animals) , forest (land connected with forest), fallow (land which can be cultivated , but has been left unused for the season), cultivable waste – (land which can be cultivated but which has been lying fallow for more than five years)

LAND USE Land as we know is used for different purposes such as cultivation of crops, forestry, grazing livestock, construction of buildings, houses, canals and for mining and manufacturing. The different uses that land is put to are commonly referred to as land use. The pattern of land use varies from one region to another. It may also vary within region overtime. Increase in the population in many parts of the world has converted large parts of the forests into croplands, agricultural lands into urban residential areas, commercial complexes and industrial areas. Different factors are responsible for the changes in the land use pattern of a country or a region at a given time. The land use, in any part of the world, depends on Physical factors and Human factors

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL PHYSICAL FACTORS

Topography

Climate

Soil

Physical Factors Distribution of rocks and minerals

Water

These also include aspects like 

slope of the land,

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elevation and extent of temperature and precipitation,

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Presence or absence of soil cover,

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availability of surface and ground water,

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Nature of rocks and minerals.

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL HUMAN FACTORS

Population distribution

Government Policy

Human Factors

Land Tenure

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Development in Science & Technology

CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL After observing the table we understand the pattern of land utilization is different in different parts of the world, if we observe Brazil has 66 percent of forest cover whereas India has 57 percent under cropland. Now let us study the map below on land utilization in the world.

It is observed that fertile river valleys and plains are the most populated areas of the world especially in tropical and subtropical regions of the world because they are suited to agriculture. Over 66 percent of the world population is concentrated in subtropical and multitude zones. 50 percent of the world’s population lives in the urban areas and the figure is expected to go up. These urban areas need more land for settlements, setting up of industries and other purposes which increase the pressure on the land. As a result, more and more agricultural land is getting converted into urban colonies. The exploration of minerals and forest resources, oil and natural gases, development of canal irrigation etc have dramatically affected land- use.

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL LAND DEGRADATION Land degradation refers to the decline in productivity of cultivated land. Generally, land degradation results from unsuitable and unscientific land use.

FACTORS RESPONSIBLE FOR LAND DEGRADATION  Overgrazing is the grazing of natural pastures at shocking intensities above the livestock carrying capacity; the resulting decrease in the vegetation cover is a leading cause of wind and water erosion. It is a significant factor in Afghanistan.

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL  Agricultural activities that can cause land degradation include Shifting cultivation without adequate fallow periods, absence of soil conservation measures, fertilizer use, and a host of possible problems arising from faulty planning or management of irrigation. They are a major factor in Sri Lanka, Bangladesh, and in north-eastern parts of India.  Establishment of industries and urbanization

URBANIZATION

INDUSTRIALIZATION

 In recent years industrial effluents and wastes have become causes of land and water pollution in several parts of India.

 Mining and industry are two important activities of man which cause degradation of land. Mining leads to degradation of land.

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With geometric precision, a Maryland mining operation works to extract minerals. Mining takes place on the Earth's surface, as seen here, as well as underground. While technology has improved mining technology, there are still human and environmental costs involved.

 The mineral processing like grinding of lime stone for cement industry and calcite and soapstone for ceramic industry generates heavy amount of dust and releases it in the atmosphere. It latter on settles down in the surrounding areas affecting infiltration of water and crop cultivation.  Deforestation and careless management of forests.

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL  Over irrigation is responsible for land degradation due to water logging, leading to increase in salinity and alkalinity in the soil.

 Desertification - is the degradation of land in any dry lands. Caused by a variety of factors, such as climate change and human activities, desertification is one of the most significant global environmental problems.

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CAUSES FOR LAND DEGRADATION IN ASIA-PACIFIC

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL CONSERVATION OF LAND RESOURCES

With a land area of 29.2 percent all over the earth, we humans need to plan our land use very carefully and skilfully. We need to conserve our lands for the future generations. Land must be planned properly to provide best results. Suitable methods should be adopted:  Check soil erosion  Check desertification  Control water logging of soil  Aforestation  Land reclamation  Regulated use of chemical pesticides and fertilizers  Check on overgrazing  Reclaim wastelands so that they are bought back to other uses

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL  Increase productivity of the land with improved farming methods such as balanced use of manures and fertilizers, organic farming, regulated irrigation, crop rotation and multiple cropping.  Every bit of land must be utilised in the best possible way, with the least harm to the natural environment. We must ensure that this delicate resource does not get converted in to badlands.

NOT ONLY A TREE IS CUT DOWN

HUMUS represents the very dark organic material that is noticeable at the surface of most soils. It is renewed by leaf fall and root decay. SOIL RESOURCE Of all the land resources, soil is our prime resource. The plants that grow on the Earth’s land areas could not exist without the thin, loose, surface layer that we call soil. It is important to us because: 

Plant, animal and human life, are directly dependent on soil.

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Besides food, fibres that provide us with clothing and other products of daily life are also grown on soil.

It takes but a moment for us to dig up a spade full of garden soil, but it has taken the processes of nature countless centuries to create it. The first step in soil building is the weathering of rocks to form the regolith- an accumulation of rock debris above the bedrock. Once living organisms like mosses and lichens become active in this layer, they combine with the mineral matter in the rock debris to form soil. Soils are therefore composed of 13

CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL minerals and organic substances. As the soil develops, more and more living organisms especially plants grow on the upper layer and then die. They decompose within the soil and layer of humus develops. Soil contains not only organic but also inorganic substances. Organic materials include plant and animal decay, which is the humus, the higher the amount of organic material or humus, the higher is the fertility of the soil. Inorganic materials include varieties of salts such as nitrogen, potassium, magnesium, sulphur, phosphorous, calcium, and iron derived from the bedrock. SOIL PROFILE Suppose you cut a slice of soil like you would cut a slice of a cake, you will see various layers in the soil. These layers are called soil horizons. The manner in which these horizons are arranged in soil is known as a soil profile. The soil profile is different in different places. The main layers or horizons in the soil are – 

Top soil (A): This layer is dark in colour, has a fine texture, has a high content of organic matter (or humus) and is vital for plant growth.

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Sub soil (B): This layer is just below the top soil. It consists of sand, silt and clay, but has only minor amounts of organic matter.

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Parent material (C): This horizon usually consists of unconsolidated rock a trial from which the A and B Layers have been formed. This zone has no humus nor does it have any soil structures.

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Bedrock (D): This layer lies at the depth below the C Horizon and consists of a solid rock. Soil formation is controlled by the following factors

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Factors affecting soil formation

NATURE OF THE PARENT ROCK

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TIME

TOPOGRAPHY

CLIMATE

LIVING ORGANISMS

Nature of the parent rock: The parent rock determines the basic characteristics of Soil. The inorganic elements and minerals a soil contains will be similar to those contained in the parent rock. For example, if sandstone was the parent rock, the soil will be sandy, while shale gives rise to clayey soil.

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Time: The nature of the soil depends on the length of time that the parent materials have been exposed to weathering and have supported vegetation. The longer the time a soil takes to form, the more mature it will be.

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Topography: Third factor influencing soil formation is the topography. If the land is hilly, the soil will be washed down as fast as it forms. Such areas have thin, immature soils. Low flat plains in contrast, promote soil formation and development. These areas have a thick, mature soil cover; a good drainage system also brings about chemical changes in the soil.

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Climate: Developing soils are influenced most by climate. Temperature and moisture influence the rate of physical and chemical weathering and so determine the rate of soil formation. Decomposition of organic matter in the soil is also influenced by climate .The climate also dictates the kind of vegetation that will contribute to the organic constituents of the soil.

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL Living organisms: like earthworms, are important in aerating the soil they burrow through it. Roots of plants also aerate the soil, while holding it in place thereby checking soil erosion.

SOIL TYPES Soils are classified on the basis of colour, texture, fertility, mineral content, etc. Climate and vegetation mainly determine the distribution of soil types in the world. 

Regions of Perpetual snow and ice are characterised by infertile tundra soils. The frozen subsoil makes the topsoil shallow and poorly drained.

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South of the tundra , in the cool , humid coniferous forest belt , the needles from the trees fall to the ground and decay slowly to create an acidic , greyish soil, known as PODSOLS or PODZOL , Russian for ‘alkaline ashes’, they become fertile with careful management .

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In the warm temperate lands with more humid climates, grey, brown, forest pod sol soils develop, these are fertile soils

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Red and yellow pod sol soils are found in milder climates. They have limited matter and are less fertile.

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Prairie soils are blackened by the mass of grass roots and are called black earths or Chernozems in the Russian steppes. They are extremely fertile.

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Soils are called Latsols or laterites occur in the tropics and subtropics, where they are high temperatures and heavy rains. Iron in these soils causes it to have a red or yellow colour.

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Sandy desert soils are typical of arid regions. Containing little organic matter, they are light yellowish and not fertile.

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Mountain and hilly areas show no fixed pattern of soil. Here soils are generally thin and immature. 16

CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL INDIA has a variety of soil types due to the varied topography, rainfall and differences in parent rock. In India we have alluvial soil, Red soil, Laterite soils Black soil ‘desert soil and mountain soil. The map illustrates where each is found.

D0 YOU KNOW? The Alluvial soil is the most fertile soil in the world. SOIL DEGRADATION Soil degradation is an evolution that occurs when soil losses its quality and productivity. Human activities and natural disasters are primarily responsible for soil degradation. The main cause of soil degradation is soil erosion. Soil erosion is the removal of soil by running water, wind or other agents of erosion. It represents the physical loss of a layer of soil. Soil exhaustion or soil impoverishment, on the other hand, is the deterioration of the soil that becomes deficient in nutrients due to improper cultivation techniques. Running water is a major agent of soil erosion, especially on slopes, or when rivers are in flood. Wind is also a powerful erosion agent, as it erodes soil which is dry, loose and with no vegetation cover.

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL Over cropping, multi-cropping, shifting agriculture, over – grazing, deforestation, slope cultivation, dry farming and over – irrigation all exhaust the soil of its potential to yield a good crop.

Contour ploughing

Terracing

Windbreaks and Shelterbelts

Strip farming

Aforestation SOIL CONSERVATION Soil conservation is an effort made by humans to prevent soil erosion and thereby retain the soil fertility of the soil. Soil conservation is possible if it is managed properly using soil management techniques and adopting the following measures:  Contour ploughing – ploughing at right angles to the slope, following the contour of land, prevents excessive soil loss and reduces run off by water. 18

CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL  Terracing: slopes cut into series of step like terraces which allow the soil to remain stable and retain water. This is especially important in mountainous areas  Strip farming – crops may be cultivated in alternate strips , some of which may be kept fallow while others are sown with different crops .as these crops ripen at different times, there is no time when the entire area is left bare or exposed to the agents of erosion  Crop rotation – the same crop must not be grown in a field for more than two years as it exhausts soil fertility. It is best to alternate nitrogen fixing crops with grains and fibre crops so that fertility is returned to the soil.  Wind breaks and Shelterbelts - tall growing crops and trees planted on the margins of fields act as wind breaks and help to slow runoff

by water. Earth bunds

or

embankments also help check soil erosion  Aforestation –areas which are left bare experience maximum soil erosion. Aforestation and reforestation schemes prevent this from happening as tree roots bind soil together and protect it. Trees absorb the impact of falling rain  Overgrazing by animals – this must be checked and grass should be allowed to regrow so that it protects the topsoil from wind and rain  Use of fertilizers – continuous cultivation exhausts soil nutrients. Soil fertility must be maintained by the application of manures or fertilisers. Phosphates, potash and nitrates must be added to the soil. However , a balance of organic and chemical fertilizers must be used, as excessive use of chemical fertilisers damages the soil, and gets absorbed into the crops  Proper water management and balanced irrigation techniques allow even marginal and useless dry lands to be bought under cultivation.

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL WORKSHEET 1 Class : VII Section : ___ 1 What percentage of the earth’s surface is land? a) 50 % b) 30%

c) 60% d) 40%

2 Land is generally used for a) Cultivation of crops b) Construction of buildings c) Grazing of livestock d) All of these 3 Land which can be cultivated ,but has been left unused for the season is called a) Fallow

b) cultivable waste c) arable land d) pasture land

4 Everything available in our environment which can be used to satisfy our needs , provided , it is technologically accessible , economically feasible and culturally acceptable can be termed as a) Development b) resource c) planning d) product

5 Explain the term ‘land use’ or land use pattern. ___________________________________________________________________ ___________________________________________________________________ 6 Land is considered to be an important and limited resource. Justify __________________________________________________________________________ __________________________________________________________________________ 7 State the physical factors that determine the changes in the land use pattern of a country. __________________________________________________________________________ _________________________________________________________________________ 20

CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL 8 How does mining play an important role in determining the land use pattern of a region? __________________________________________________________________________ __________________________________________________________________________ 9 Draw a rough plan of your immediate neighbourhood. Try to depict through it the land use pattern of your area (e.g. parks. Shopping centres, roads, dwellings )

10 Study the above given diagram and answer the following question. 10.1.Write any two categories under which the land use area has increased. __________________________________________________________________________ __________________________________________________________________________ 10.2.What do you think is the cause for the increase? __________________________________________________________________________ __________________________________________________________________________ 10.3.Write two categories under which the land use area has decreased. Mention the cause for the decrease. __________________________________________________________________________ __________________________________________________________________________ 11. Study the data and answer the given questions 21


11.1Name the country which has the highest percentage of cropland. Why? _____________________________________________________________________ _____________________________________________________________________ 11.2 Which country has the lowest percentage of cropland? Why _________________________________________________________________________ _________________________________________________________________________ 11.3Which country has the highest percentage of forests? Why? __________________________________________________________________________ __________________________________________________________________________ 12 Identify the type of land use pattern shown in the pictures given below marked by A,B,C,D,E and F.

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13. The following picture shows different types of land use

On the basis of your understanding mention few benefits and harmful effects for each of these types of land use.

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL Worksheet No-2 : VII Div : Name Class : 1 Which of the following factors are responsible for land degradation a) Excessive exploitation of land b) Deforestation c) Untreated industrial effluents d) All of the above 2 Some of the common methods of land conservation are a) Deforestation b) Uncontrolled use of chemical pesticides c) Controlled mining d) Overgrazing 3 Which agent is responsible for maximum land degradation? a) Wind

b) water

c) glaciers

d) overgrazing

4 The factor responsible for maximum land degradation is a) Human activities

b) Wind c) Salinity d) Soil erosion

5 land degradation can be controlled by a) Deforestation b) Checking soil erosion c) Desertification d) None of the above 6 Explain the following : 6.1.Land degradation. ________________________________________________________________________ ______________________________________________________________________ _______________________________________________________________________

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL 6.2.Desertification _____________________________________________________________________ _____________________________________________________________________ 7 Explain any four human activities which are mainly responsible for land degradation in India _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ 8 Complete the following Graphic organizer The land under permanent pasture has decreased over the years. What are its consequences? _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ 9 Mention certain agricultural activities that cause land degradation in different areas. _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL WORK SHEET_3 1 The layer of soil that has the maximum amount of humus is called. a) Parent material b) The bedrock c) Top- soil d) The subsoil 2 Soil is formed by the process of a) Denudation b) Deposition c) Weathering d) Erosion 3 Which of the following is an important factor in the formation of soil? i)

Relief

ii)

Parent rock

iii)

Climate

iv)

Vegetation

a) Only i) and ii) b) Only ii) and iii) c) Only iii) and iv) d) All of the above. 4 Time taken for the formation of one cm. of soil is a) One year b) Hundred years c) Five hundred years d) Thousands of years

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL 5 Soil type that occurs in the tropical area is known as a) Latsols or laterites b) Prairie soils c) Blackearths d) Podzol 6 Explain the following Soil profile ________________________________________________________________________ _________________________________________________________________________ 7 Soil is considered to be a primary resource. Explain. _________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ 8 Mention the criteria on the basis of which soils can be classified in the Indian subcontinent. _________________________________________________________________________ _________________________________________________________________________ 9 Mention the types of soil found in our country India. _________________________________________________________________________ _________________________________________________________________________

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL 10 Complete the following

Organic substances found in soil Inorganic substances found in soil 11 Complete the following ( any four factors responsible for soil formation)

factors affecting soil formation

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL 12 What is hummus and why is it useful for soil? _________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ 13 O, A, B C and R signify different layers of soil. Identify.

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14 On the political map of India identify the soil types in I, II, III, IV.

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL WORKSHEET 4 Class : VII Div : 1. Terrace farming and contour ploughing are practiced to a) Bring rainfall b) Conserve soil c) Erode soil d) Rear animals 2. Carrying away of the top soil by wind , water or human action a) Soil degradation b) Soil erosion c) Soil conservation d) Land degradation 3. Contour ploughing and terrace cultivation is common along a) River valleys b) Steep slopes c) Deltas d) Plains 4. Carrying away of the top soil by wind , water or human action e) Soil degradation f) Soil erosion g) Soil conservation h) Land degradation 5. State in detail some factors that exhaust the soil of its potential to yield a good crop. __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL 6. When does degradation of soil occur? __________________________________________________________________________ _________________________________________________________________________ __________________________________________________________________________ 7. How does aforestation help control soil erosion? __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ 8. Distinguish between contour ploughing and terrace farming

9. Soil erosion has become a pressing problem in the world. Justify __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL 10. Observe the picture and answer the questions that follow

What does the picture depict? _________________________________________________________________________ 11. How does this method help in conserving the soil on a large scale? _________________________________________________________________________ __________________________________________________________________________ _________________________________________________________________________ 12. Observe the given picture and answer the questions that follow

12.1.Which type of soil erosion is depicted in the picture? __________________________________________________________________________ __________________________________________________________________________

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CBSE – i CLASS VII GEOGRAPHY STUDENTS’ MANUAL 12.2.Name the agent responsible for this type of soil erosion. __________________________________________________________________________ __________________________________________________________________________ 12.3.What is the name given to these lands that are extensively eroded? _________________________________________________________________________ _________________________________________________________________________

RESOURCES 1. Frank CCE middle school by Kripal Singh 2. Time space and people by Chitra Srnivas 3. Getting ahead with social science by Vijay Sridharan 4. The unique planet by llela Sachdev 5. Cornerstone – integrated social science by Mrs. Kanchan sood , Mrs. Meera Sharma 6. Gosse geography in focus by Widdowson smith knill Links:  http://moef.nic.in/soer/2001/ind_land.pdf  http://en.wikipedia.org/wiki/Land_degradation  http://www.pon.nic.in/citizen/science/ppcc-new/ppcc/chapter7.pdf

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