CHAPTER 2: Structure and Physiography NCERT SOLUTION CLASS 11TH Indian Physical Environment | EDUGROWN NOTES

SHORT ANSWER TYPE QUESTION:

Q1.If a person is to travel to Lakshadweep, from which coastal plain does he prefer and why?
Answer
The person will prefer to travel from the western coastal plains because the Lakshdweep islands are situated in Arabian Sea which distance is lowest from this coast. Therefore, it will take the least time to reach the Lakshadweep.

Q2. Where in India will you find a cold desert? Name some important ranges of this region.

Answer

The cold desert in India is located in the north eastern part of the Kashmir Himalayas, which lies between the Greater Himalayas and the Karakoram ranges.

Q3.Why is the western coastal plain is devoid of any delta?

Answer

The western coastal plains are narrow and have steep slope. The rivers flow rapidly in one part and hence they don’t form any deltas. Therefore, the western coastal plain is devoid of any delta.

Q4.Make a comparison of the island groups of the Arabian Sea and the Bay of Bengal.

Answer

Island groups of the Arabian Sea	Island groups of the Bay of Bengal
This island group consists of about 36 islands of which 11 are inhabited.	This island groups consist of about 572 islands/islets.
These are situated between 8°N-12°N and 71°E -74°E longitude.	These are situated roughly between 6°N-14°N and 92°E -94°E.
The entire group of islands is broadly divided by the Eleventh degree channel, north of which is the Amini Island and to the south of the Canannore Island.	The entire group of island is divided into two broad categories – the Andaman in the north and the Nicobar in the south.
The entire island group is built of coral deposits.	These islands are an elevated portion of submarine mountains.
Minicoy is the largest island with an area of 453 sq. km.	The two principal groups of islands include the Ritchie’s archipelago and the Labrynth island.

Q5.What are the important geomorphological features found in the river valley plains?

Answer

The river valley plains are formed by the alluvial deposits brought by the rivers. The important geomorphological features found in the river valley plains are:

• Bhabar is a narrow belt ranging between 8-10 km parallel to the Shiwalik foothills at the break-up of the slope.

• Terai: South of the Bhabar is the Tarai belt, with an approximate width of 10-20 km where most of the streams and rivers re-emerge without having any properly demarcated channel, thereby, creating marshy and swampy conditions known as the Tarai.
→ This has a luxurious growth of natural vegetation and houses a varied wild life.

• Bhangar: It is composed of old alluvium. These areas are less prone to flooding and less fertile as well.

• Khadar: It is composed of new alluvial deposits. These areas are prone to flooding and are very fertile

• Delta:  A river delta is a landform that occurs at the mouth of a river near where the river flows into the ocean. For example, the famous Sunderbans delta.

Q6. If you move from Badrinath to Sunderbans delta along the course of the river Ganga, what major geomorphological features will you come across?

Answer

Badrinath is situated along Ganga river. The Sunderban delta is on the mouth of Ganga and Brahmaputra in Bay of Bengal. If we are moving from Badrinath to Sunderbans delta along the course of the river Ganga, we will come across various of geomorphological features. As we start moving we will come across gorges, V-shaped valleys, rapids, waterfalls, etc. We will also see places where tributaries meet main river Ganga. After sometime, we will enter into northern plains. We will see various erosional and depositional landforms such as sand bars, meanders, oxbow lakes and braided channels. At last, we will reach our destination, swampy and marshy area known as Sunderbans delta formed by the Ganga and Brahmaputra river.

Long Answer Type Questions:

Q1.Write a detailed on Kashmir or north-western Himalayas.
Answer:
Kashmir or North-western Himalayas:

• Region extents over Jammu and Kashmir, Himachal Pradesh and Uttaranchal.
• It comprises of Ladakh, Zaskar and Pir Panjal.
• The north-eastern parts of Kashmir Himalayas is a cold desert which lies between greater Himalayas and Karakoram ranges.
•  Between Pir Panjal and Great Himalayas in Dal Lake and Valley of Kashmir.
• Important Glaciers here are:
  • Siachen
  • Baltora
  • Babura
  • Hispar.
• Kashmir valleys are known for Karewas. Karewas are thick deposits of glacial clay and other material embedded with moraines (Zafran-Saffron is cultivated here):
• Important passes: Zoji La on the Great Himalayas, Banihal on Pir Panjal range, Photu La-Zaskar range, Kharaung La on Ladakh range. Thadala, Nitila, Lepulekh in Uttaranchal Nathula in Sikkim in Himachal Pradesh.
• Himalayas are spread between river Indus to river Mahi. The total extent of western Himalayas is 700 km and 400 km in width.
• Kashmir Himalayas, Punjab Himalayas and Kumaon Himalayas are its sub¬division.
• The important lakes are: Dal lake and Wular lake (in Jammu and Kashmir and they are freshwater lakes), Pangong Tso, Tso Moriri ( they are salt water lakes and they are situated in Jammu and Kashmir.
• Important rivers: Indus, Jhelum and Chenab.
• Important pilgrimages Vaishno Devi, Amaranth and Charar-e-Sharif.
• The southernmost part of the region has longitudinal valleys known as Duns, e.g. Jammu Dun and Pathankot Dun.

Q2.Explain the characteristics or features of Northern plains?
Answer:
The Northern Plains-

• These plains extend approximately 3,200 from the east to the west.
• The average width of these plains varies between 150-300 km.
• The maximum depth of alluvium deposits varies between 1,000-2,000 m.
• The area covered by northern plains is 7 lakhs square km and is most densely populated region of country.
  From north to South, these plains can be divided into three sub divisions: Bhabar, Tarai and Alluvial Plains. The alluvial plains can be further divided into the Khadar and the Bhangar.

Bhabar

• It is a narrow belt ranging between 8-16 km parallel to the Shiwalik foothills at the breaking of the slopes.
• The streams and rivers coming from the mountain deposit heavy materials of rocks and boulders and at times, disappear in this zone.

Tarai

• Its approximate width is of 20-30 km where most of the streams and river re-emerge without having any properly demarcated channel, thereby, creating marshy and swampy condition known as the Tarai.
• It has a luxurious growth of natural vegetation and houses a varied wild life.

Alluvial Plains

• These plains have characteristic features of mature stage of fluvial erosional and depositional landforms such as sand bars, meanders, ox- bow lakes and braided channels. The Brahmaputra plains are known for their riverine islands and sand bars.
• The mouths of these mighty rivers also form some of the largest deltas of the world, for example, the famous Sunderbans delta.
• These river valley plains have a fertile alluvial soil cover which supports a variety of crops like wheat, rice, sugarcane and jute, and hence supports a large population.

Q3.Explain the physical features of coastal plains.
Answer:
On the basis of the location and active geomorphological processes, it can be broadly divided into two:

• The western coastal plains;
• The eastern coastal plains.

The western coastal plains are an example of submerged coastal plain. It is a narrow belt and provides natural conditions for the development of ports and harbours. Kandla, Mazagaon, JLN port. Navha Sheva, Marmagao, Mangalore, Cochin, etc. are some of the important natural ports located along the west coast.

Extending from the Gujarat coast in the north to the Kerala coast in the south, the western coast may be divided into following divisions – the Kachchh and Kathiawar coast in Gujarat, Konkan coast in Maharashtra, Goan coast and Malabar coast in Karnataka and Kerala respectively. As compared to the western coastal plain, the eastern coastal plain is broader and is an example of an emergent coast.

There are well- developed deltas here, formed by the rivers flowing eastward in to the Bay of Bengal. These include the deltas of the Mahanadi, the Godavari, the Krishna and the Kaveri. Because of its emergent nature, it has less number of ports and harbours. The continental shelf extends up to 500 km into the sea, which makes it difficult for the development of good ports and harbours.

It is believed that the city of Dwaraka which was once a part of the Indian mainland situated along the west coast is submerged under water. Because of this submergence it is a narrow belt and provides natural conditions for the development of ports and harbours. Kandla, Mazagaon, JLN port Navha Sheva, Marmagao, Mangalore, Cochin, etc. are some of the important natural ports located along the west coast.

Q4.How are Arunachal, Himachal, Purvachal and Uttaranchal Himalayas different from each other?
Answer
Arunachal Himalayas

• These extend from east of Bhutan to Diphu pass in East.
• Important peaks are- Kangtu and Namcha Barwa.
• They are bisected by fast flowing rivers forming deep gorges.
• Brahmaputra flows through deep a gorge after crossing Namcha Barwa.
• Subansiri, Dihang, Dibang and Lohit are the important rivers. Perennial rivers have high rate of fall which helps to generate hydro-electricity.

The Himachal and Uttarakhand Himalayas-

• It lies between river Ravi and Kali in the east.
• Northernmost part is the extension of the Ladakh desert.
• All these ranges Nimadi, Himachal and Chivalric are prominent here.
• Hill stations are Dharamshala, Mussoorie, Shimla, Ranikhet and Almora.
• Shiwaliks are important for dun formation. For example- Kalka dun, Nalagarh dun (Dehradun is the largest- dun, its length is 35-45 km and width is 22-25 km.)
• Tribes common are Dhotia’s which migrates to higher region in summer.
• Valley of flowers- Nanda devi is also situated here.
• Gail’s, the Manipur Pilgrimages common are Kedarnath, Badrinath, Hemkund Sahib.

The Eastern Hills and mountains or Purvachal.

• General alignment from the north to south direction.
• In north, they are known as Patkai Bum, Naga hills, the Manipur hills and in the south, as Mizo or Lushai Hills. This forms Purvanchal range.
• Most of these ranges are separated from each other by numerous small rivers.
• The barak is an important river in Manipur and Mizoram.
• Mizoram has a large lake known as ‘loktak lake is made up of soft unconsolidated deposits.
• Mizoram and Manipur are tributary of Barak river, which is the turn tributary of Meghna rivers in eastern part of Manipur are tributaries of Chindwin which is in turn is a tributary of Ireawady of Myanmar.

Q5.Differentiate between:
(i) Bhabar and Tarai
Answer:
Difference between Bhabar and Tarai.

Bhabar	Basis	Tarai
It lies along the foot of shiwalik from Indus to Tista	Location	It lies to the south of Bhabar and runs parallel to it.
It is 8 to 16 km wide.	Width	It is 20-30 km wide.
It comprises of pebbles studded rocks in the shape of porous bed.	Composition	It is composed of firmer alluvial particles and is covered by forests.
Due to the porousity of rocks the stream disappear and flow underground.	Appearance	The underground streams of Bhabar reappear here giving rise to a wet marshian.
It is not suitable for agriculture.	Suitability	It is reclaimed for agriculture purpose.

(ii) Bhangar and Khadar
Answer:
Difference between Bhangar and Khadar

Bhangar	Basis	Khadar
It is a highland composed of old alluvium.	Composition	It’s a lowland composed of new alluvium.
It is always above the level of flood plains.	Flood	It is flooded almost every year.
It comprises of canvanious nodules	Fertility	It comprises of clay soil which is normally fertile
It is not much suited for agriculture.	Suitability	It is suited for agriculture. Intensive agriculture is practiced.
It is known as dhaya in Punjab.	Other name	It is known as bate in Punjab.

(iii) Western Ghats and Eastern Ghats
Answer:
Difference between Western Ghats and Eastern Ghats;

Western Ghats	Basis	Eastern Ghats
They form continuous chain from Gulf of Combay to Kanniyakumari.	Location	They form a discontinuous chain of low hills from Odisha to Coromandel coast.
They are having an elevation of 900-1100m.	Peaks	They are denuded peaks and have lesser elevation than 900 km.
They are divided as four regions or the four hills Sahyadri hills in Maharashtra, Nilgiri in Karnataka and Tamil Nadu, Anaimalai hills and Cardamom hills in Kerala.	Hills	Some of the important ranges include the Javadi hills, the Palconda range, the Nallamala hills, the Mahendragiri hills, etc.
The western ghats get southward monsoon.	Rainfall	The eastern ghat gets rainfall from north-east monsoon.
The highest peak in western ghat is Anamudi (2695 m)	Highest Peak	Highest peak of eastern ghat is Mahendragiri (1501 m)
The height of the mountain increases from north to south.	Change in height	Height increases from south to north.
The westward flowing river are Narmada and Tapi.	Rivers	Eastward flowing rivers are Godavari Krishna, Kaveri, Mahanadi, etc.

(iv) Peninsular Plateau and Indo-Gangetic Plateau
Answer:
Difference between Peninsular Plateau and Indo-Gangetic Plateau

Peninsular Plateau	Basis	Indo-Gangnetic Plateau
It is triangular plateau bounded by Vindhyas western ghats, and eastern ghats.	Stretch	It is alluvial plain stretching from Punjab to Assam valley.
The relief of this plateau is uneven. Its average height is more than 600 m above the sea level.	Level	This is a level plain for about 200 m in height above the sea level.
The climate is hot and humid.	Climate	The summers are hot and winters are cold.
Kaveri, Krishna, Godavari, Mahanadi, Narmada, Tapi are seasonal rivers.	Rivers	Ganga, Yamuna, Brahmaputra are perennial rivers.
Area has black soil.	Soil	Alluvial soil is found.
Known as storehouse of minerals and important for industries.	Known for	Known for agriculture and provide employment to people.

(v) Western Coastal Plains and Eastern Coastal Plains
Answer:
Difference between Western Coastal Plains and Eastern Coastal Plains

Western coastal plain	Basis	Eastern coastal plain
They lie between western ghats and Arabian sea.	Location	They lie between eastern ghats and bay of Bengal.
They are narrow alluvial plain which are separate by hilly terrains.	Width	They are wider plain (80-120 km) with well developed deltas of the rivers.
The western coastal plains are further divided into two parts: Konkan coast, Malabar coast	Furtherclassification	They are further divided as northern circus and Coromandel coast.
They are known for lagoons estuary and kayals (backwater), which are known for fishing and Inland transportation.	Known For	They are known for deltas formed by the rivers and is more suitable for agriculture.
They receive rainfall from south­west monsoons.	Rainfall	They receive rainfall by retreating or north-west monsoon.
The important rivers are Narmada, Tapi	Rivers	The important rivers are Krishna, Kaveri, Mahanadi, etc.
They are submerged coast.	Merging	They are emergent coast.

(vi) Northern Plains and Coastal Plains
Answer:
Difference between Northern Plains and Coastal Plains

Northern Plains	Basis	Coastal Plains
They are located on foot hills of Himalayas and above peninsular plateau.	Location	They lie between Arabian Sea, Western Ghats and Eastern Ghats and Bay of Bengal.
They spread between the area of 3200 square km and the width is 240-320 km.	Stretch	They are spread from Gujarat to Kanniyakumari and Odisha to Kanniyakumari.
Rivers originating from Himalayas and peninsular plateau has form these plains by depositing sediments brought by rivers.	Rivers	Most of the rivers originating from peninsular plateau like Krishna, Kaveri, Godavari, Mahanadi move eastward and form delta whereas Narmada and Tapi move westward from Estuaries.
Due to fertile alluvial soil and water supply they are known for agriculture.	Suitability	They are drained by perinial rivers and are important for fishing, lagoons, and harbours.
They are divided as Indus plains, Ganga plains and Brahmaputra plains.	Divisions	They are divided as Konkan coast and Malabar coast, Northern Circar on eastern side and Coromandel coast.
They are important for riverine features like natural leaves, sand bars, etc.	Known for	They are important for ports, harbours, kayals and backwaters.

(vii) Himalayas and Central Highlands
Answer:
Difference between Himalayas and Central Highlands

Himalayas	Basis	Central Highlands
They are the young fold mountains of comparatively recent origin.	Young vs. Old	They are part of oldest structure of Indian subcontinents.
They are the world’s highest mountains and the Mount Everest is the highest peak of the world.	Height	They are formed of low hills and no high peak is there worth mentioning in the area.
The mighty rivers like Indus, Ganga, Brahmaputra originate beyond the Himalayas.	Rivers	Quite a few rivers like Tapi, Chambal, Betwa, Narmada, originate from these highland.
They are made up of sedimentary rocks.	Composition	They are formed by Igneous and metamorphic rocks.
They are formed at the edge of northern plains.	Location	They are formed at the edge of Deccan Plateau.
Important hill stations are Srinagar, Shimla, Dhalauzi, Dharamshala, Mussoorie, etc.	Hill stations	They are no well-known hill stations.
Himalayas are known for glaciers and perennial rivers.	Glaciers and rivers	No glaciers and non- perennial river are there.
They have beautiful passes and river valleys.	Scenicbeauty	They are low-lying hills with less common features.