Class 6 Social Science Chapter 3 Notes Landforms and Life
Landforms :
- A landform is a physical feature on the surface of our planet Earth.
- The landforms take shape over millions of years and have a significant connection with the environment and life.
- Landforms have different climates and are home to a variety of flora and fauna.
- Humans are similar to most of the mammals that live on land. They have adapted to all landforms, but the number of people living on different kinds of landforms varies throughout the world.
- Human adaptation and resilience to the landforms are represented by the various ways in which people have settled on different landforms.
- Landforms can broadly be divided into three categories i.e., mountains, plateaus and plains. However, there are few more landforms according to experts such as deserts.
Mountains :
- The landforms that are much higher than the surrounding land are considered as mountains. Mountains can be recognised by a broad base, steep slopes and a narrow summit.
- The features of mountains vary according to their altitude (height). The high-altitude mountains are generally covered with snow while, at lower altitudes, the snow melts every summer and turns into water.
- This water flows down towards the plain as rivers. Therefore, many rivers originate from mountainous regions.
- The Ganga is the largest river in India. It originates from the Himalayas. The Ganga is nearly 2,500 km long. The Ganga has numerous tributaries. Some of them are the Yamuna and the Ghagara.
- These two tributaries also originated from the . Himalayas. Other tributaries like the Son or Sone, originate from the Vindhya Range to the South of the Ganga plain.
- Highlands with lower heights, less steep slopes and rounded tops are called hills.
- Most of the world’s mountains are grouped in mountain ranges, such as the Himalayas in Asia, the Alps in Europe and the Andes in South America. Some of these ranges stretch for thousands of kilometres.
What is Snow?
In most of India, precipitation is in the form of rain and hail. But at higher altitudes, precipitation is in the form of snow. It covers the landscape in a soft and beautiful white blanket. Snow and hailstones are precipitation of water in a solid state.
Some Major Mountains of the World :
- Mount Everest between Tibet (China) and Nepal, and Kanchenjunga between Nepal and the Indian state of Sikkim are the two highest peaks of the Himalayan range.
- Mount Aconcagua in South America is the highest peak of the Andes.
- Mount Kilimanjaro in Eastern Africa is an isolated mountain that is not part of any range.
- Mont Blanc in Western Europe is the highest mountain of the Alps.
- Anamudi in Kerala, also known as Anai Peak, is the highest mountain in South India.
Young and Older Mountains :
- Mountains with tall and sharp peaks, like the Himalayas, are relatively young. They were formed recently in Earth’s history. They are called young because they are still in the developmental stage and their height is increasing continuously.
- Mountains that are short and have rounded tops, like the Aravallis are considered ‘old mountains’. Due to continuous erosion, their peaks are rounded.
Mountain Environment :
- Mountain slopes are often covered with a type of forest called montane forests. In these forests, conifer trees such as pines, firs, spruce and deodar are common.
- Conifer trees are tall and cone-shaped, with thin, pointed leaves. At higher altitudes, only grasses, mosses and lichens are found.
- Deep forests, flowing rivers, lakes, grasslands and caves in the mountains are home to diverse fauna, for example, the golden eagle, the peregrine falcon, the Canadian lynx, the mountain hare, etc.
Life in the Mountains :
Agriculture:
- The mountain terrain is usually rugged or rough and has steep slopes. Hence, agriculture can be practised only in a few valley regions in the mountains.
- Cultivation is practised on the slopes by cutting steps into the slope. This is called terrace farming.
- In many mountainous regions of the world, herding is preferred as an occupation over agriculture.
Tourism :
- Tourism is an important source of income for the people living in the mountains.
- The scenic beauty of the mountains attracts numerous tourists. Some tourists also go to the mountains for sports such as skiing, hiking, mountaineering and paragliding.
- However, when more tourists visit the mountains, it puts pressure on the environment of the mountains.
Culture :
- For many centuries, people have also travelled to the mountains for pilgrimages to holy sites. Mount Kailash in Tibet is believed to be sacred by followers of Hinduism, Buddhism, Jainism and Bon (an ancient Tibetan religion).
- Most traditional communities worldwide consider the mountains as sacred places and worship them.
- Mount Everest is the highest mountain in the world at $8,849 m. It is known by many names like ‘Chomolungma’ in Tibet, which means Mother Goddess of the World.
- It is also known as Sagarmatha in Nepal which means Goddess of the Sky. Thus, it is worshipped by Tibetans and Nepalis.
Women Climbers of India :
- Bachendri Pal was the first Indian woman to climb Mount Everest in 1984. She was awarded Padma Shri in 1984 and Padma Bhushan in 2019. She started climbing mountains from a young age and led many women’s climbing expeditions.
- Arunima Sinha lost a leg in an accident when she was 31. With Bachendri Pal’s encouragement and training, she managed to climb Mount Everest in 2013.
- She has climbed the highest peak of every continent, including Mount Vinson in Antarctica. She was awarded Padma Shri in 2015.
Plateaus :
- A plateau is a landform that is higher from the surrounding land and has a flat surface. Some of its sides are often steep slopes.
- The height of plateaus can vary from a few hundred metres to several thousand metres.
- Like mountains, plateaus can be young or old in terms of the Earth’s history.
Two examples of plateaus are –
- Tibetan Plateau It is the world’s largest plateau. The average altitude of the Tibetan plateau is 4,500 m , therefore it has been nicknamed the Roof of the World. From East to West, it is nearly 2,500 km long, which is equal to the distance from Chandigarh to Kanyakumari.
- Deccan Plateau The Deccan Plateau of Central and South India is one of the oldest plateaus in the world. It was formed through volcanic activity millions of years ago.
Minerals :
- Just like mountains, plateaus are rich in mineral deposits. They are called storehouses of minerals. Therefore, mining is a major activity on plateaus.
- For example, the East African Plateau is famous for gold and diamond mining. In India, huge reserves of iron, coal and manganese are found in the Chhota Nagpur Plateau.
- The plateau environment is very diverse across the world. Many plateaus have rocky soil and they are less fertile than plains. Hence, plateaus are less favourable to farming. However, farming can be done in lava plateaus (that is, formed through volcanic activity), as they are often rich in black soil.
Waterfall :
- Numerous waterfalls can be seen in the plateau regions.
- The Victoria Falls on the Zambezi River in Southern Africa, the Hundru Falls on the Subarnarekha River in the Chhota Nagpur Plateau and the Jog Falls on the Sharavati River in the Western Ghats are some examples of waterfalls.
- The Nohkalikai Falls in Cherrapunji Plateau (Meghalaya) has a height of 340 meters.
Plains :
- Plains are areas of land that are mostly flat or have very gentle slopes. They do not have any large hills or deep valleys.
- The height of plains is generally not more than 300 metres above sea level. Plains also support a variety of flora and fauna.
- Floodplains are a type of plains which is formed by rivers originating in mountain ranges.
- Floodplains are formed where the rivers collect particles of rock, sand and silt called sediments. These sediments make the soil very fertile. Therefore, these plains are ideal for growing all kinds of crops.
Life in the Plains :
- A large population of the world resides within the plain areas.
- About 40 crore people of the total population in India, live in Ganga plain (often called the Gangetic plain). Thus, it is affected by the problems of high population and pollution.
Agriculture :
- Cultivation was developed in the fertile regions of plains thousands of years ago. In most of the plains of the world, the major occupations of people are river fishing and agriculture.
- In Gangetic plains, agriculture is the major occupation. Food crops such as rice, wheat, maize, barley and millet are grown in this region. Fibre crops such as cotton, jute and hemp are also grown in the Gangetic plain.
- Traditionally agriculture is mostly rainfed (land is irrigated by rainfall) but in recent decades, irrigation facilities like networks of canals or groundwater are used to water the fields.
- Irrigation has increased agricultural production, but it has also contributed to the depletion (or decrease) of groundwater. This is a challenge for the future of agriculture in the region.
Culture and Economy :
Rivers in mountain ranges or plains around the world have immense cultural value. Many communities have considered a river’s source and its confluence with one or two other rivers to be sacred. In India, many festivals, ceremonies and rituals are conducted at such locations.
As plains have a gentle slope, transportation by rivers is easy and supports a lot of economic activities. In earlier days, people also used rivers to travel from one place to another. Even today, there are stretches along the Ganga where people prefer to use boats to move from one place to another.
Deserts :
- Deserts are considered to be large and dry landforms with very little precipitation. They also have a unique flora and fauna.
- There are two types of deserts- hot and cold. Examples of hot deserts are the Sahara Desert in Africa or the Thar Desert in the North-West of the Indian subcontinent. Examples of cold deserts include the Gobi Desert in Asia. Some experts also consider the Antarctica continent as a desert.
- Humans have adapted to most of the deserts irrespective of their harsh living conditions.
- In India, communities living in the Thar Desert, or migrating through it, have rich cultural traditions related to the desert such as folk songs and legends.
Five Tinais :
In ancient Tamil Sangam poetry, there are five tinais. These tinais are five landforms that are related to specific gods, and lifestyles, moods or emotions. The following table shows the main occupation of the five landforms
Tinal | Landform | Main Occupation |
Kurinji | Mountainous regions | Hunting and gathering |
Mullai | Grassland and forests | Cattle rearing |
Marudam | Fertile agricultural plains | Farming |
Neydal | Coastal region | Fishing and seafaring |
Palai | Desert region | Journeying and fighting |
Glossary :
→ Altitude: The height of an object above sea level. Examples: the altitude of a mountain, the altitude of a bird or plane in flight, and the altitude of a satellite.
→ Montane forest: A type of forest that grows in mountainous regions.
→ Moss: A small green plant without flowers or true roots, often spreading in a cushion-like cover.
→ Lichen: A plant-like organism that generally clings to rocks, walls or trees.
→ Terrain: A piece or stretch of land, from the point of view of its physical features.
→ Adaptation: Adaptation is a change or evolution in an animal or plant that helps it survive better in its environment.
→ Valley: A valley is a low area of land between hills or mountains, often where a river or stream flows.
→ Flash floods: A sudden local flood, often caused by a cloudburst.
→ Landslides: The sudden collapse of a mass of Earth or rock from a mountainside.
→ Avalanche: The sudden fall of snow, ice or rocks from a mountainside often occurs when the snow starts melting.
→ Cloudburst: A sudden violent rainstorm.
→ Tributaries: The rivers and streams that join the other larger rivers.
→ Erosion: it is the process by which natural forces like wind, water, and ice break the rocks and soil, gradually moving them from one place to another.
→ Precipitation: Precipitation is any form of water that falls from the sky. It includes rain, snow, sleet and hail.
→ Confluence: It is the place where two or more rivers or streams meet and combine into one.
→ Expedition: A journey that is meant for a specific reason, like adventure, research, etc.
→ Undulating surface: Such a surface is identified as one that has a smooth, wavy shape with gentle rises and falls.
→ Sea level: It is the average height of the ocean’s surface, used as a standard to measure the elevation of land and the depth of the sea.
→ Sediments: Sediments are small particles of rock, soil and other materials that are carried by wind, water, or ice.
→ Resilience: It is the capacity to meet challenges and difficulties, adapt to them or overcome them.
Free from the burden of human beings, may the Earth with many heights, slopes and great plains, bearing plants endowed with varied powers, spread out for us and show us her riches!… The Earth is my mother and I am her child.
Atharva Veda, Bhumi Sukta (‘Hymn to the Earth’)
Introduction
Humans, like most mammals, live on land. Land, as you may have noticed, has many forms and features; its appearance changes a lot from one region to another. Suppose that you are travelling by road from the region known as Chhota Nagpur in Jharkhand, reach Prayagraj in Uttar Pradesh, and go on to Almora in Uttarakhand. On the way, you will see very different landscapes. In fact, you will encounter three major landforms, which we will now explore.
LET’S EXPLORE
- As a class activity, form groups of four or five students and observe the school’s surroundings. What kind of landscape do you see? Will the landscape change a few kilometres away? Or within some 50 kilometres? Compare with other groups.
- In the same groups, discuss a journey that any of you has made through a region of India. List the different landscapes seen on the way. Compare with other groups.
A landform is a physical feature on the surface of our planet Earth. Landforms take shape over millions of years and have a significant connection with the environment and life. They can broadly be divided into three categories
– mountains, plateaus and plains (Fig. 3.1).
These landforms have different climates and are home to a variety of flora and fauna. Humans have adapted to all landforms, but the number of people living on different kinds of landforms varies throughout the world.
Mountains
Mountains are landforms that are much higher than the surrounding landscape. They can be recognised by a broad base, steep slopes and a narrow summit. Depending on their height, some mountains are covered with snow. At lower altitudes, the snow melts every summer and turns
into water that feeds rivers. At high altitudes, the snow may never melt, leaving the mountain permanently snowcapped.
Other highlands with a lower height, less steep slopes and rounded tops are called hills.
THINK ABOUT IT
What is snow? Unless you live in a Himalayan region (such as Kashmir, Ladakh, Himachal Pradesh, Uttarakhand, Sikkim, Arunachal Pradesh), you may never have seen snow! In the rest of India, most precipitation is in the form of rain and hail. But at higher altitudes, if it is cold enough, snow will fall, covering the landscape in a soft and beautiful white blanket. Snow and hailstones are nothing but precipitation of water in a solid state.
Most of the world’s mountains are grouped in mountain ranges, such as the Himalayas in Asia, the Alps in Europe and the Andes in South America. Some of these ranges stretch for thousands of kilometres.
Fig. 3.2 shows pictures of six mountains of the world. Fig. 3.3 brings them together to give a visual impression of their relative heights from top to bottom. Mount Everest (between Tibet (China) and Nepal) and Kanchenjunga (between Nepal and the Indian state of Sikkim) are the two highest peaks of the Himalayan range. Mount Aconcagua (in South America) is the highest peak of the Andes. Mount Kilimanjaro in eastern Africa is an isolated mountain that is not part of any range. Mont Blanc in Western Europe is the highest mountain of the Alps. Anamudi (in Kerala, also known as ‘Anai Peak’) is the highest mountain in south India.
Mountains with tall and sharp peaks, like the Himalayas, are relatively ‘young’, which means that they were formed recently in the Earth’s history – but that is still millions of years ago! Shorter and more rounded mountains and hills, like the Aravalli Range, are much older and have been rounded by erosion. Sometimes, as with the Himalayas, upliftment as well as erosion continue to this day. (You will learn more in Science about such processes and their causes; let us just say here that some mountains of the world, like the Himalayas, are still growing in height.)
Mountain environment
Mountain slopes are often covered with a type of forest called montane forest, where conifer trees such as pines, firs, spruce and deodar are common. These conifer trees grow tall and cone-shaped, with thin, pointed leaves. At higher altitudes, the trees give way to grasses, mosses and lichen.
Here are two verses from a long poem by Kalidasa, who lived at least 1,500 years ago and is often considered to be the greatest poet of ancient India. The poem, Kumdrasambhava, begins with an invocation to the Himalayas. (This is a simplified translation from the Sanskrit.)
In the north rises Himalaya, the Lord of mountains, like a living god, who measures the Earth and stretches from the western to the eastern oceans….
From it the wind comes down, carrying spray from descending Ganga, shaking the deodar trees, opening the peacocks’ tail feathers and cooling the mountain people after they hunt deer.
Discuss the verses and the following questions in class.
- What are the ‘western to the eastern oceans’? Can you locate them as well as the ‘Lord of mountains’ on Fig. 5.2?
- Why is Ganga mentioned? (Hint: There could be several reasons.)
Deep forests, flowing rivers, lakes, grasslands and caves in the mountains are home to diverse fauna, for instance, the golden eagle, the peregrine falcon, the Canadian lynx, the snow leopard, the ibex, the Himalayan tahr, the mountain hare, the yak, the grey fox and the black bear (Fig. 3.4).
DON’T MISS OUT
Ganga’ is the Indian name of the largest river originating in the Himalayas. In English, ‘Ganges’ is also used. Nearly 2,500 km long, this river has numerous tributaries (that is, other rivers joining it). Some of them, like the Yamuna and the Ghagara, also originate in the Himalayas. Others, like the Son or Sone, originate from the Vindhya Range to the south of the Ganga plain.
Life in the mountains
The mountain terrain is usually rugged or rough, and has steep slopes. This means that regular farming can only be practised in some valleys. Cultivation is practised on the slopes by cutting steps into the slope (Fig. 3.5). This is called terrace farming. In many mountainous regions of the world, herding is the preferred occupation over agriculture.
Tourism is often an important source of income for the people living in the mountains. The crisp mountain air and scenic beauty attract many tourists. Some tourists also go to the mountains for sports such as skiing, hiking, mountaineering and paragliding. For many centuries, people have also travelled to these uplands for pilgrimages to holy sites. But an excessive inflow of visitors can also put the fragile mountain environment under pressure; it is often difficult to find the right balance.
DON’T MISS OUT
- Bachendri Pal started climbing mountains from a young age and led many women’s climbing expeditions. She was the first Indian woman to climb Mount Everest in 1984 and was awarded Padma Shri the same year (and Padma Bhushan in 2019).
- Arunima Sinha lost a leg in an accident when she was 31. With Bachendri Pal’s encouragement and training, she managed to climb Mount Everest in 2013, and went on to climb the highest peak of every continent, including Mount Vinson in Antarctica! She was awarded Padma Shri in 2015.
LET’S EXPLORE
These images (Fig. 3.6 on page 50) depict a few challenges that people living in the mountains may face. Discuss them in groups in the class and write one paragraph on each. Also discuss why, despite many such challenges, people still choose to live in the mountains.
DON’T MISS OUT
Many traditional communities around the world consider mountains to be sacred places and worship them. Mount Everest, the highest mountain in the world at 8,849 m, has many names. Tibetans call it ‘Chomolungma’, which means ‘Mother Goddess of the World’ and worship the mountain as such. Nepalis call it ‘Sagarmatha’, meaning ‘Goddess of the Sky’. Similarly, Mount Kailash in Tibet is held sacred by followers of Hinduism, Buddhism, Jainism and Bon (an ancient Tibetan religion). Such reverence for mountain summits is also found elsewhere in India, as well as in other parts of the world.
Plateaus
A plateau is a landform that rises up from the surrounding land and has a more or less flat surface; some of its sides are often steep slopes. Like mountains, plateaus can be young or old in terms of the Earth’s history. Two examples of plateaus are the Tibetan Plateau, the largest and highest plateau in the world, and the Deccan Plateau. The height of plateaus can vary from a few hundred metres to several thousand metres.
DON’T MISS OUT
- The Tibetan Plateau has an average altitude of 4,500 m, which explains why it has been nicknamed the ‘Roof of the World’! From east to west, it is nearly 2,500 km long – the distance from Chandigarh to Kanyakumari.
- The Deccan Plateau of central and south India is one of the oldest plateaus in the world, formed through volcanic activity millions of years ago.
Like mountains, plateaus are rich in mineral deposits; they have been called ‘storehouses of minerals’. As a result, mining is a major activity on plateaus, where many of the world’s largest mines are found. For example, the East African Plateau is famous for gold and diamond mining. In India, huge reserves of iron, coal and manganese are found in the Chhota Nagpur Plateau.
The plateau environment is very diverse across the world. Many plateaus have a rocky soil, which makes them less fertile than plains (see next section) and therefore less favourable to farming. An exception is that of lava plateaus (that is, formed through volcanic activity), as they often have a rich black soil.
Plateaus are also home to many spectacular waterfalls. The Victoria Falls on the Zambezi River in southern Africa, the Hundru Falls on the Subarnarekha River in the Chhota Nagpur Plateau and the Jog Falls on the Sharavati River in the Western Ghats are a few such waterfalls. The Nohkalikai Falls (Fig. 3.7) drop down 340 metres from the Cherrapunji Plateau (in Meghalaya).
Plains
Plains are landforms that have an extensive flat or gently undulating surface. They do not have any large hills or deep valleys. They are generally not more than 300 metres above sea level.
Floodplains are one type of plains formed by rivers originating in mountain ranges, where they collect particles of rock, sand and silt called ‘sediments’. These sediments are carried all the way to the plains, where the rivers deposit them, making the soil very fertile. As a result, these plains are ideal for growing crops of all kinds, and agriculture is a major economic occupation in this landform. Plains also support a variety of flora and fauna.
LET’S EXPLORE
Use the colour code in Fig. 3.8 to add a landform to each name. For instance, ‘Tibetan plateau’, ‘Rocky range’, ‘Nile plain’. (You do not have to remember the names in this map.)
LET’S EXPLORE
The picture in Fig. 3.9 has been taken from a satellite. It captures a portion of north India from a high altitude. Observe and discuss the image as a class activity.
- Which colour is the Ganga plain?
- What does the white expanse represent?
- What does the brown expanse at the bottom left of the image represent?
Life in the plains
Thousands of years ago, the first civilisations developed around rivers in fertile plains. In our times too, a large part of the world’s population lives in plains.
About 40 crore people, more than one-fourth of the total Indian population, live in India’s Ganga plain (often called the ‘Gangetic plain’). As with many other plains of the world, the major occupations of people in this region include river fishing and agriculture. Food crops such as rice, wheat, maize, barley and millets are grown. Fibre crops such as cotton, jute and hemp are also grown in the Gangetic plain. Traditional agriculture has been mostly rainfed (that is, watered through rainfall). In recent decades, however, agriculture has turned to irrigation, with water brought to the fields through networks of canals or pumped from groundwater. While irrigation has increased agricultural production, it has also contributed to the depletion (or decrease) of groundwater. This presents a challenge for the future of agriculture in the region. Some of the other problems affecting the Ganga plains include high population and pollution.
Whether in mountain ranges or plains, rivers around the world have carried immense cultural value. In particular, many communities have considered a river’s source and its confluence with one or two other rivers to be sacred. In India, numerous festivals, ceremonies and rituals are conducted at such locations.
Because plains have a gentle slope, river navigation is easy and supports a lot of economic activities. In earlier days, people also used rivers extensively to travel from one place to another. Even today (Fig. 3.10 on page 56), there are stretches along the Ganga where people prefer to use boats to move around!
LET’S EXPLORE
→ Can you give examples of river sources or confluences from your region that are regarded sacred by any community?
→ Visit a nearby river and observe all activities there, whether economic or cultural. Note them down and discuss with your classmates.
→ Name some popular tourist destinations in India and identify the category of landform they are associated with.
In this chapter, we explored the three main landforms. But its surface is very complex and experts often define a few more landforms. One such landform is the desert. Deserts are considered to be large and dry expanses with very little precipitation. Their flora and fauna are also unique. Some deserts are hot, like the Sahara Desert in Africa or the Thar Desert in the northwest of the Indian Subcontinent. Others are cold, like the Gobi Desert in Asia. (Some experts also describe the Antarctica continent as a desert.)
Despite harsh living conditions, humans have adapted to most of the deserts. In India, communities living in the Thar Desert, or migrating through it, hold rich cultural traditions, such as folk songs and legends, related to the desert.
The diverse ways in which humans have made all landforms their home is a testimony to our adaptability and resilience.
The five tinais of ancient Tamil Sangam poetry are five landscapes associated with certain specific deities, lifestyles, moods or emotions (such as love, longing, separation, quarrel, etc.). This table only lists the characteristics of the five landscapes and the main human occupations in each:
Tinai | Landscape | Main occupation |
Kurihji | mountainous regions | hunting and gathering |
Mullai | grassland and forests | cattle rearing |
Marudam | fertile agricultural plains | farming |
Neydal | coastal regions | fishing and seafaring |
Palai | arid, desert-like regions | journeying and fighting |
These five tinais constitute a different classification of landforms than the one we have seen, but they reflect a keen awareness of the diverse regions and their characteristics. They also illustrate the deep connection between humanity and the natural environment. (You do not need to remember the details of the tinais, but the concepts they reflect need to be understood.)
Before we move on …
- Landforms are classified into three main types – mountains, plateaus and plains. They have very different physical characteristics and environments.
- Throughout history, people’s lives and activities have been much impacted by the type of landform they have lived in. These landforms are an integral part of culture across the world. Indian culture, in particular, has celebrated them in diverse ways.
- Each landform offers different challenges as well as opportunities.