Class 7 Social Science Life In Desserts Exam Notes

Class 7 Social Science Life In Desserts Exam Notes Please refer to the examination notes which you can use for preparing and revising for exams. These notes will help you to revise the concepts quickly and get good marks.

Class 7 Social Science – Life in the Deserts (Exam Notes)

Introduction

Desert: A desert is an arid region characterised by low rainfall, scanty vegetation and extreme temperatures. Depending on the temperature, there can be hot deserts or cold deserts.

The Hot Desert – Sahara

The Sahara is the world's largest desert. It has an area of around 8.54 million sq. km. It touches eleven countries: Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Sudan, Tunisia and Western Sahara. Besides vast stretches of sand, the Sahara has gravel plains and elevated plateaus with a bare rocky surface. These rocky surfaces may be more than 2500 m high at some places.

Climate

1. The climate of the Sahara is scorching hot and parched dry.
2. It has a short rainy season.
3. The sky is cloudless and clear.
4. Moisture evaporates faster than it accumulates.
5. Days are unbelievably hot. The temperature during the day may soar as high as 50°C, heating up the sand and the bare rocks, which in turn radiate heat and make everything around hot.
6. The nights may be freezing cold, with temperatures nearing zero degrees.

Flora and fauna

1. The vegetation of the Sahara includes cactus, date palms and acacia.
2. In some places there are oases – green islands with date palms around them.
3. Camels, hyenas, jackals, foxes, scorpions and many varieties of snakes and lizards are the prominent animals living there.

People

1. Despite its harsh climate, the Sahara has been inhabited by various groups of people who pursue different activities.
2. Among them are the Bedouins and the Tuaregs.
3. These groups are nomadic tribes who rear livestock such as goats, sheep, camels and horses.
4. These animals provide them with milk, and hides from which they make leather for belts, slippers and water bottles. The hair is used for mats, carpets, clothes and blankets.
5. They wear heavy robes as protection against dust storms and hot winds.
6. The oases in the Sahara and the Nile Valley in Egypt support a settled population.
7. Since water is available, people grow date palms.
8. Crops such as rice, wheat, barley and beans are also grown. Egyptian cotton, famous worldwide, is grown in Egypt.
9. The discovery of oil, a product in great demand throughout the world, in Algeria, Libya and Egypt is constantly transforming the Sahara.
10. Other minerals of importance found in the area include iron, phosphorus, manganese and uranium.
11. The cultural landscape of the Sahara is undergoing change. Gleaming glass-cased office buildings tower over mosques, and superhighways crisscross the ancient camel paths. Trucks are replacing camels in the salt trade. Tuaregs are seen acting as guides to foreign tourists. More and more nomadic herdsmen are taking to city life, finding jobs in oil and gas operations.

The Cold Desert – Ladakh

1. Ladakh is a cold desert lying in the Great Himalayas, on the eastern side of Jammu and Kashmir.
2. The Karakoram Range in the north and the Zanskar Mountains in the south enclose it.
3. Several rivers flow through Ladakh, and the Indus is the most important of them.
4. The rivers form deep valleys and gorges. Several glaciers are found in Ladakh, for example the Gangri glacier.

Climate

1. The altitude in Ladakh varies from about 3000 m in Kargil to more than 8000 m in the Karakoram.
2. Because of the high altitude, the climate is extremely cold and dry.
3. The air at this altitude is so thin that the heat of the sun can be felt intensely.
4. The day temperatures in summer are just above zero degrees, and the night temperatures are well below −30°C.
5. It is freezing cold in the winters, when the temperature may remain below −40°C for most of the time.
6. As it lies in the rain shadow of the Himalayas, there is little rainfall, as low as 10 cm every year.
7. The area experiences freezing winds and burning hot sunlight.
8. If you sit in the sun with your feet in the shade, you may suffer from sunstroke and frostbite at the same time.

Flora and fauna

1. Due to high aridity, the vegetation is sparse.
2. There are scanty patches of grasses and shrubs for animals to graze.
3. Groves of willows and poplars are seen in the valleys.
4. During the summers, fruit trees such as apples, apricots and walnuts bloom.
5. Several species of birds are sighted in Ladakh. Robins, redstarts, the Tibetan snowcock, ravens and hoopoes are common. Some of these are migratory birds.
6. The animals of Ladakh are wild goats, wild sheep, yaks and special kinds of dogs.
7. The animals are reared for milk, meat and hides. Yak's milk is used to make cheese and butter.
8. The hair of sheep and goats is used to make woollens.

People

1. The people here are either Muslims or Buddhists. Several Buddhist monasteries dot the Ladakhi landscape with their traditional gompas. Some famous monasteries are Hemis, Thiksey, Shey and Lamayuru.
2. In the summer season, people are busy cultivating barley, potatoes, peas, beans and turnip.
3. The climate in the winter months is so harsh that people keep themselves engaged in festivities and ceremonies.
4. The women are very hardworking. They work not only in the house and the fields, but also manage small businesses and shops.
5. Leh, the capital of Ladakh, is well connected by both road and air.
6. National Highway 1A connects Leh to the Kashmir Valley through the Zoji La Pass.

Tourism

1. Tourism is a major activity, with many tourists streaming in from within India and abroad.
2. Visits to the gompas, treks to see the meadows and glaciers, and witnessing ceremonies and festivities are the important activities.

Change in life

The life of the people is undergoing change due to modernisation. But the people of Ladakh have learned over the centuries to live in balance and harmony with nature. Because resources like water and fuel are scarce, they are used with reverence and care. Nothing is discarded or wasted.

1.The climate of the Sahara desert is scorching hot and parch dry.

9. The hair of the sheep and goat is used to make woollens.