3. Physiography and Drainage/ Class 10 Geography
Video Explanation : Drainage of Brazil
Video Explaination: Physiography of Brazil Video Explaination: Physiography of India part 1Class 10th Subject: Geography
3. Physiography and Drainage
(NOTES)
• Another term for physical geography is Physiographic.
• Its a branch of Geography dealing with natural features.
• For example: Valleys plateaus, Mountains, hills, plains, coastal plains, peninsula,island etc.
3. Physiography and Drainage
(NOTES)
• Another term for physical geography is Physiographic.
• Its a branch of Geography dealing with natural features.
• For example: Valleys plateaus, Mountains, hills, plains, coastal plains, peninsula,island etc.
[Visit the YouTube channel for better understanding:
https://youtu.be/oExJoH0qOTY ]
Five Major Physiographic Divisions of India:
1. The Himalayas
2. The North Indian Plains
3. The Peninsula
4. The Coastal Plain
5. The Island Groups
1. The Himalayas:
1. The young fold mountain.
2. It comprises of many of the highest peaks of the world.
3. It also comprises of many large rivers like Ganga, Brahmaputra, Yamuna and Indus rivers.
5. It formed only a few million ( 40 – 50 Million) years ago.
6. Fold mountains are formed when two or more of earth’s tectonic plates are pushes together.
7. At this point of collision, the compressing boundaries, rocks and debris are warped and folded into rocky outcrops, hills, mountains and entire mountain range.
The extend of Himalayas:
• Extend from Pamir Knot in Tajikistan to the east.
• Tajikistan is a landlocked country.(the smallest country in the Asia)
• It stretches across the Northeastern portion of India.( From Jammu-Kashmir to Aruna chal Pradesh.)
• It covers approximately 2400 km and pass through the nation’s of India, Pakistan, Afghanistan, China, Bhutan and Nepal.
• Parallel Ranges: It isnot a single mountain but it is a series of range of mountains.
There are many parallel ranges in the system.
1. Transhimalayan ranges to the North.
• Consists of the highest mountains above 6000 metres and mostly snow capped.
• It is a 1600km mountain range.
• It includes Karakoram range, Ladhak range etc.
2. The Greater Himalaya/ Humadri:
• The highest mountain range.
• The world’s highest peak, Mount Everest (8848 m, Nepal) as well as the highest peaks such as Kanchenjunga, Lhotse and Nanga Parbat are the part of the Greater Himalaya.
• Average elevation is 6000 m.
• Consists of Glacier; Gangotri glacier Satopanth Glacier.
3.Lesser Himalayas:
• It is also called the Inner Himalayas or Lesser Himalayas or Himachal with 3700 to 4500 m .
• The Himachal range also parallels the lower Shiwalik or Churia Range to the south.
• The Pir Panjal is the largest range of the lesser Himalayas.
Shiwaliks:
• It stretches from the Indus River about 2400 km eastwards close to the Brahmaputra River, spanning across the northern parts of the Indian Sub Continent.
• It is 10 – 50 km wide with an average elevation of 1500-2000m.
• Sivalik literally means ‘tresses of Shiva’. ( A long lock of a woman’s hair)
• These ranges are young to old respectively.
2: NORTH INDIAN PLAINS:
• MEANING: A large area of flat land with few trees (0-150m)
• These plains lie in between Himalaya Mountains in the North and the Peninsula in the south.
• Extend:
• It extends from Rajasthan and Punjab in the west to Assam in the east.
• It is mostly a flat low lying area at the altitude of 0 – 150 meters.
1.The Highlands:
• An area of high or mountainous land / plateaus.
• The Brazilian Highlands or plateaus are extensive geographical region, covering most of the eastern, southern and central part of Brazil, in all approximately half of the country’s land area or some 4,500,00 km2, Elevation- 2891 m .
• The Southern Brazil is occupied by an extensive plateau.
THE CORE PART:
• Brazilian Highlands and Guyana highlands together form the Core of South American Continent.
• The main part of Guyana highlands is in Venezuela.
• It extends upto French Guiana.
• It covers the states of Roraima, Para and Amapa in the North.
LOWER PART OF THE HIGHLANDS:
• The highest peak of Brazil, Pico de Neblina is 3014 m high and lies on the borders between Brazil and Venezuela.
ALTITUDE:
• Regions to the east and south of the Brazilian highlands have an altitude of more than 1000m.
• But in other parts, the altitude is between 500-1000m.
• SLOPE:
• It gradually slopes towards North and slpoes are not very steep.
THE TRIBUTARIES OF AMEZON:
• Flowing through this region make rapids and waterfalls.
• The slopes are steep but not abrupt.
RIVERS:
• A number of rivers take off from the terminal portion of the highlands and flow northwards to meet Atlantic Ocean.
• Major rivers like Uruguay, Paraguay and Parana from the Southern slopes of highlands and enter Argentina.
• Its slope towards the east is steep and it appears in the form of an escarpment.
2. THE GREAT ESCARPMENT:
• Escarpment: a long, steep, slope, especially one at the edge of a plateau/ separating areas of land at different heights.
• It occupies a very small area.
• But the nature of its slope and the effect it has on the Climate makes a separate physiographic region.
• Because of the escarpment, the eastern side of the highlands is demarcated/ separated.
ALTITUDE:
• The altitude of the escarpment is 790m.
• The hight decreases in some regions.
• It is very steep from Sao Paulo to Porto Alegre.
• The escarpment acts as a barrier to the southeast Trade winds giving rise to the rainshadow area in the northeastern part of the highlands.
• The region to the north this area is called ‘Drought Quadrilateral.
3) THE COASTS:
• It has a coastline of about 7400 km.
• It is divided in to two parts namely Northern and eastern coasts.
EXTEND:
• The northern coast extends from Amapa province in the north to Rio Grande do Norte in the east.
• This is called as the North Atlantic Coast.
• The eastern coast extends towards the south.
CHARACTERISTICS:
• The Northern Coast is characterized by Mouths of many rivers including Amazon.
• This is low lying region.
• On this coast lie the Marajo island and Sao Marcos Bays.
• Marajo is a large coast island located between the mouths of River Amazon and River Tocantins.
• The eastern coast receives large number of smaller rivers.
• The only major river which meets the Atlantic ocean here is Sao Francisco.
• The Brazilian coast is characterized by a large number of beaches and sand dune (bank) complexes.
• The Brazilian coast is protected in some area by Coral reef [ an underwater ecosystem characterized by reef building corals.( marine invertebrates) reef sand bar / bank] and atoll islands (ring shaped islands)
4. THE PLAINS:
• The plains are restricted/limited/confined to two areas namely the Amazon basin in the north and Paraguay-Parana Source region in the southwest.
• Amazon plains are lying between the two highlands form the largest plain land ( Guyana and Brazilian Highlands)
• Its lying in the Northern parts of Brazil generally slope eastward.
EXTENSION:
• Amazon basin is quite wide in the west (about 1300 km) and it narrows eastwards.
• WIDTH: Its width is minimum where the Guyana Highlands and Brazilian highlands come closer. (240 km)
• As the river reaches Atlantic, the width increases.
CHARACTERISTICS:
1.These are mostly forested areas and largely inaccessible due to frequent flooding and dense undergrowth.
2. Most of the Amazon plains are covered by tropical rainforests. (tropical rainforests are rainforests that occur in areas of tropical rainforests climate in which there is no dry season – all months have an average precipitation of at least 60 mm.)
3. It is the world’s largest tropical rainforest, famed for its biodiversity.
It’s crisscrossed by thousands of rivers, including the powerful Amazon.
OTHER PLAINS:
• The other plains are located to the Southwestern part of the highlands.
• They form the source region of Paraguay and Parana rivers.
• The source region of Paraguay slopes towards the South and the source region of Parana slopes towards the Southwest.
PANTANAL:
• Pantanal is one of the world’s largest wetland ( land consisting of marshes/swams, saturated land)
• It lies towards the southwest part of the highland areas.
• It is a region of swamps ( A swamp is a forested wetland. Swamps are considered to be transition zone because both land and water play a role in creating this environment. Swams are vary in size and are located all around the world. The water of a swamp may be fresh water, brackish water or sea water) and marshes in north western Mato Grosso do Sul in Brazil and it extends in to Argentina too.
5. ISLANDS OF BRAZIL:
• The islands in Brazil can be classified into coastal islands and marine islands.
• Most of them have formed due to deposition.
• Marine islands were a part of the mainland.
• They are more than 300 km away from the mainland in the Atlantic Ocean.
• These are mostly rocky and they are the top of submerged mountains.
• The islands near the coast of the South Atlantic ocean are coral islands and they are called atolls.
[ ] DRAINAGE:
• The system of water or waste liquids flowing from somewhere into the ground of down pipes.
A COMPARATIVE NOTE ON THE BASINS OF GANGA AND AMAZON RIVER:
DRAINAGE OF BRAZIL:
Three major river Basins:
1. Amazon Basin
2. Paraguay -Parana system in the southwest.
3. Sao Francisco in the eastern part of Highland and others rivers at the coasts.
1. AMAZON BASIN:
1. Size of catchment area ( the area from which rainfall flows into river, lake or reservoir) of Amazon river is 70,50,00 sq.km.
2. It collects it headwaters ( a trubutary stream of a river close to or forming part of its source) from the eastern slopes of Andes Mountain in Peru.
3. Amazon river receives huge discharge (River discharge is the volume of water flowing through a river channel;measured at any given point in cubic meters per second)Its about 2 lakhs m3/S.
4. The result of huge water discharge is Amazon cleans, removes or washes off the load supplied to it doesn't deposit and sediments at the river mouth.
5. Generally, a dense network of distributaries ( a branch of river that doesn't return to the main stream after leaving it. ( as in delta) dound at the mouth of river but such distributaries are not found at the mouth of Amazon.
6. Instead of it, a series of islands developed/ formed along the mouth of Amazon beyond the coast line into the Atlantic Ocean.
7. The width of Amazon channel at its mouth is 150 km.
8. Most of the course ( the route/ direction followed by ships or river) is suitable for navigation.
2. PARAGUAY- PARANA SYSTEM:
1. LOCATION:
• Rivers Paraguay and Parana are located in the Southwestern part of Brazil.
2. CATCHMENT:
• Both the rivers form the catchment of river Rio-de-la Plata in Argentina. [ River Plata includes areas of Southeastern Bolivia, Southern and central Brazil, the entire country of Paraguay, most of Uruguay and Northern Argentina.
3. HEADWATERS:
• River Paraguay, river Parana and river Uruguay in Extreme south of the highlands collect their headwaters from the southern portion of the highlands.
3. SAO FRANCISCO:
• It is the third important river of Brazil.
• It is a large river in Brazil, with a length of 2914 km.
• It is the longes river that runs entirely in Brazilian territory and the fourth longest in South America overall in Brazil.
• The entire basin of this river is within Brazil.
• It originates in the Canastra mountain range.
• It occupies the eastern portion of the highlands.
• It flows toward north for a distance of about 1000 km over the plateau and then takes a sharp eastward turn to enter the coastal strip along the Atlantic Ocean.
• The river is navigable for a distance od about 250 km in its downstream reaches.
COASTAL RIVERS:
• It has a number of short coastal rivers attain significance because the coastal area is densely populated.
• River Paraniba and River Itapecury flowing northward meet the North Atlantic Ocean.
• The river that enter South Atlantic Ocean collect their headwaters along the escarpment.
• River Paraguaco enters the Atlantic Ocean near Salvador town.
[ ] INDIA
[ ] DRAINAGE OF INDIA:
• Rivers are classified according to their source region into Himalayan and Peninsular rivers.
• HIMALAYAN DRAINAGE
• Major rivers in the Himalayas originate from various glaciers.
• The discharge of water increases in summer due to glaciers melt.
• It floods during monsoons too.
• These are perennial (everlasting, continuing) rivers.
• The Himalayas are drained by 19 rivers, of which Indus river system and Ganga river system cover the drainage.
• THE RIVER INDUS:
• Indus and its tributaries Jhelum, Chenab, Ravi and Satluj drain the Western Himalayas.
• They flow through the state of Jammu and Kashmir.
• They flow almost parallel to each other.
• A major tributary of river Indus is the Satluj originates near Man Sarover and flows westwards.
• Punjab plains have formed due river and its tributaries.
• Indus further flows through Pakistan and then meets the Arabian sea.
• The indus is a transboundary river of Asia and trans- Himalayan river of South and Central Asia.
• The 3,180 km (1980 miles) river rises in Western Tibet, flows north west through the disputed region of Kashmir.
• THE RIVER GANGA:
• It originates from the Gangotri glacier and crosses the Himalayas to become and east flowing river.
• Thw Ganges is transboundary river of Asia which flows through India and Bangladesh (Padma).
• The 2525 km (1569 mi) river rises in the western in the Indian State Uttarakhand.
• It flows south and east through the Gangetic plain of North India, receiving the right bank tributary, the Yamuna..
• YAMUNA: It originates at Yamunotri, is a mojor tributary of Ganga.
• BRAHMAPUTRA:
• Another major tributary of the Ganga flows through the northern part of the Greater Himalayas, crosses the Himalaya to enter India.
• When it flows through the Himalaya it is called Tsang Po.
• When it crosses the Himalayas, it is called Fihang and its eastward flow thereafter is called as Brahmaputra.
• Ganga meets its tributaries, hence its discharge increases.
• Ganga receives Brahmaputra as its tributary in its lower reaches in Bangladesh.
• Ganga delta: The huge volume of water and huge deposition has led to the formation of a large delta.
• Tributaries: Besides these Himalayan rivers, Ganga receives a number of tributaries from Peninsula like Chanbal, Ken, Betawa, Shon, Damodar etc.
• PENINSULA RIVERS:
• Its divided into east-flowing meeting the Bay of Bengal and west-flowing meeting thw Arabian Sea.
• The western Ghats are called water divide in Peninsula.
• The western Ghats are called a water divide because they act as a divide between the west flowing rivers meeting the Arabian sea and east flowing rivers meeting the Bay of Bengal.
• The peninsular rivers are rainfed ( relies on rainfall water) rivers so rarely face the problem of floods.
• They are seasonal in nature.
• In Peninsular India, the west-flowing rivers are smaller and less in number campared to east-flowing rivers.
• THE WEST FLOWING:
• The major west-flowing rivers in Peninsular India are the Narmada and Tapi.
• The west flowing rivers occupying the area between the Western Ghats and the Arabian Coastline are short in length but swift.
• This condition of short and swift river system exists in the states of Kerala, Karnataka, Maharashtra and Southern Gujrat.
• NORTHWARD FLOWING RIVERS:
• Northward flowing river system flowing in to the Gulf Of Khambhat.
• These river systems are Tapi, Narmada, Mahi and Sabarmati.
• Tapi and Narmada flow slowly through rift
valleys.
• Mahi River flows from North East to South West direction whereas River Sabarmati collecting its headwaters from the southern slopes of Aravali ranges flows in somewhat North-South direction.
• Another noteworthy river forming the catchment of Arabian Sea is River Luni.
• It originates along the western slopes of Aravali range and flows in somewhat northeast to southwest direction and flows into Gulf of Kutchch.
[ ] Rivers meeting the Bay of Bengal :
• Most of the area of the Peninsula is drained
• by the rivers flowing towards Bay of Bengal.
• The important river systems of this group are
• Mahanadi, Godavari, Krishna and Kaveri.
• Mahanadi basin occupies the northeastern
• part of the Peninsula.
• Godavari, Krishna and Kaveri originate in the eastern slopes of the Western Ghats.
• River Godavari is the second largest river system of India in terms of the catchment area.
• The Godavari is India's second longest river after the Ganga and third largest in India, drains about 10% of India's total Geographical area. Its source is in Trimbakeshwar, Nashik, Maharashtra.
• It flows east for 1465 km, draining the stated of Maharashtra, Telangana, Andhra Pradesh, Chhatisgarh and Odisha.
• To the south of Godavari is located the
basin of River Krishna.
• The Krishan River is a river in Deccan Plateau, and the third longest river of India, after Ganga &Godavari and the fourth largest in terms of water inflows and river basin area in India after The Gangs Indus and Godavari. IT IS 1400 KM (870MI ) Long. Its length in Maharashtra is 282 km.
• It major tributaries are Bhima and Tungbhadra.
• River Kaveri Basin flows through the states of Karnataka and Tamil Nadu.
• It is one of the major rivers of Peninsula. It is a river
• that has been harnessed for irrigation since a long time.
1. The Himalayas
2. The North Indian Plains
3. The Peninsula
4. The Coastal Plain
5. The Island Groups
1. The Himalayas:
1. The young fold mountain.
2. It comprises of many of the highest peaks of the world.
3. It also comprises of many large rivers like Ganga, Brahmaputra, Yamuna and Indus rivers.
5. It formed only a few million ( 40 – 50 Million) years ago.
6. Fold mountains are formed when two or more of earth’s tectonic plates are pushes together.
7. At this point of collision, the compressing boundaries, rocks and debris are warped and folded into rocky outcrops, hills, mountains and entire mountain range.
The extend of Himalayas:
• Extend from Pamir Knot in Tajikistan to the east.
• Tajikistan is a landlocked country.(the smallest country in the Asia)
• It stretches across the Northeastern portion of India.( From Jammu-Kashmir to Aruna chal Pradesh.)
• It covers approximately 2400 km and pass through the nation’s of India, Pakistan, Afghanistan, China, Bhutan and Nepal.
• Parallel Ranges: It isnot a single mountain but it is a series of range of mountains.
There are many parallel ranges in the system.
1. Transhimalayan ranges to the North.
• Consists of the highest mountains above 6000 metres and mostly snow capped.
• It is a 1600km mountain range.
• It includes Karakoram range, Ladhak range etc.
2. The Greater Himalaya/ Humadri:
• The highest mountain range.
• The world’s highest peak, Mount Everest (8848 m, Nepal) as well as the highest peaks such as Kanchenjunga, Lhotse and Nanga Parbat are the part of the Greater Himalaya.
• Average elevation is 6000 m.
• Consists of Glacier; Gangotri glacier Satopanth Glacier.
3.Lesser Himalayas:
• It is also called the Inner Himalayas or Lesser Himalayas or Himachal with 3700 to 4500 m .
• The Himachal range also parallels the lower Shiwalik or Churia Range to the south.
• The Pir Panjal is the largest range of the lesser Himalayas.
Shiwaliks:
• It stretches from the Indus River about 2400 km eastwards close to the Brahmaputra River, spanning across the northern parts of the Indian Sub Continent.
• It is 10 – 50 km wide with an average elevation of 1500-2000m.
• Sivalik literally means ‘tresses of Shiva’. ( A long lock of a woman’s hair)
• These ranges are young to old respectively.
2: NORTH INDIAN PLAINS:
• MEANING: A large area of flat land with few trees (0-150m)
• These plains lie in between Himalaya Mountains in the North and the Peninsula in the south.
• Extend:
• It extends from Rajasthan and Punjab in the west to Assam in the east.
• It is mostly a flat low lying area at the altitude of 0 – 150 meters.
MAIN TWO PARTS OF NORTH INDIAN PLAINS:
1.EASTERN PART/ GANGA PLAINS:
• The part lying to the east of the Aravalis is the basin of the river Ganga and therefore known as Ganga plains.
• Its slope is towards East side.
DELTA:
• Most of the West Bengal State of India & Bangladesh together constitute the delta of Ganga & Brahmaputra system.
• Its known as Sunderban.
2. WESTERN PART:
• The western part of North Indian Plains is occupied by desert.
• It is also know as Thar Desert or Marusthali.
• It is also known as The Great Indian Desert, is a large arid region in the North western part of the Indian subcontinent that covers an area of 200000 km2 & forms a natural boundary between India & Pakistan.
• Most of Rajasthan is occupied by this desert.
3. PLAINS OF PUNJAB:
• This regon is spread to the west of Aravalis and Delhi ranges.
• To the north of the desert lie the plains of Punjab.
• These plains have formed as a result of the depositional work by river Sutlaj & its tributaries.
• The slope is towards the west.
• Agriculture is largely practised in this region because the soil here is very fertile.
3. THE PENINSULA:
• Peninsula is a landform that extends from a mainland & is surrounded by water on most, but not all of its borders.
• It can be defined as a piece of land bordered by water on three sides.
• The Indian Peninsula lies to the South of North Indian Plains and narrower/ tapering towards the Indian Ocean is called Indian peninsula.
• It consists of many plateaus ( fairly level land/ tableland) and hill ranges.
• The large Deccan Plateau in southern India is located between the Western Ghats and the Eastern Ghats & loosely defined as the peninsular region between these ranges that is south of the Narmada river.
• To the north, it is bounded by the Satpuda and Vindhya Ranges.
• The Aravalis in the north are the oldest fold mountain here.
• Aravali range: It’s a line of peaks the Aravali range is a mountain range in Northern India running approximately 670 km in a South-West direction.
4. THE COASTAL PLAINS:
1.EASTERN PART/ GANGA PLAINS:
• The part lying to the east of the Aravalis is the basin of the river Ganga and therefore known as Ganga plains.
• Its slope is towards East side.
DELTA:
• Most of the West Bengal State of India & Bangladesh together constitute the delta of Ganga & Brahmaputra system.
• Its known as Sunderban.
2. WESTERN PART:
• The western part of North Indian Plains is occupied by desert.
• It is also know as Thar Desert or Marusthali.
• It is also known as The Great Indian Desert, is a large arid region in the North western part of the Indian subcontinent that covers an area of 200000 km2 & forms a natural boundary between India & Pakistan.
• Most of Rajasthan is occupied by this desert.
3. PLAINS OF PUNJAB:
• This regon is spread to the west of Aravalis and Delhi ranges.
• To the north of the desert lie the plains of Punjab.
• These plains have formed as a result of the depositional work by river Sutlaj & its tributaries.
• The slope is towards the west.
• Agriculture is largely practised in this region because the soil here is very fertile.
3. THE PENINSULA:
• Peninsula is a landform that extends from a mainland & is surrounded by water on most, but not all of its borders.
• It can be defined as a piece of land bordered by water on three sides.
• The Indian Peninsula lies to the South of North Indian Plains and narrower/ tapering towards the Indian Ocean is called Indian peninsula.
• It consists of many plateaus ( fairly level land/ tableland) and hill ranges.
• The large Deccan Plateau in southern India is located between the Western Ghats and the Eastern Ghats & loosely defined as the peninsular region between these ranges that is south of the Narmada river.
• To the north, it is bounded by the Satpuda and Vindhya Ranges.
• The Aravalis in the north are the oldest fold mountain here.
• Aravali range: It’s a line of peaks the Aravali range is a mountain range in Northern India running approximately 670 km in a South-West direction.
4. THE COASTAL PLAINS:
• The Coastal Plains of India lie on either side of the Deccan Plateau along the western and eastern Coasts of India.
• It extends fŕom Rann of Kutch in the west to West Bengal in the East.
• Its divided into the Western and Eastern coastal Plains.
• India is blessed with a long coastline extending for approximately 7500 km.
• It lies to the Western and eastern part of the peninsula.
THE WESTERN COAST:
• The western coast borders the Arabian Sea.
• It is by & large a rocky coast.
• Characteristics Western Ghats:
• It rises steeply from the west coast.
• It orginates from Tapti river till Kanyakumari.
• Western Ghats are higher than the Eastern Ghats and have an average height of 900 to 1100 m.
• Originating rivers: Godavari, Kaveri, Krishna, Thamiraparani & Tungabhadra rivers.
THE WESTERN COAST:
• The western coast borders the Arabian Sea.
• It is by & large a rocky coast.
• Characteristics Western Ghats:
• It rises steeply from the west coast.
• It orginates from Tapti river till Kanyakumari.
• Western Ghats are higher than the Eastern Ghats and have an average height of 900 to 1100 m.
• Originating rivers: Godavari, Kaveri, Krishna, Thamiraparani & Tungabhadra rivers.
5. The Island group:
• India has many small and large islands along the coast of the mainland.
• These are included in the coastal island group.
• India has two large group of islands, one each in Arabian sea and in the Bay of Bengal.
• The islands in the Arabian Sea are known as Lakshadweep whereas the islands in the Bay of Bengal are called the Andaman and Nicobar Islands.
•
• Most of the islands in Lakshadweep are atoll islands.
• They are small in extent and not very high.
• Islands in the Andaman group are mainly volcanic islands.
• They are large with hills in their interior parts of includes an island called Barren Island which has only active volcano in India.
• There are atolls in the Nicobar group too.
[ ] PHYSIOGRAPHY OF BRAZIL
• It extends fŕom Rann of Kutch in the west to West Bengal in the East.
• Its divided into the Western and Eastern coastal Plains.
• India is blessed with a long coastline extending for approximately 7500 km.
• It lies to the Western and eastern part of the peninsula.
THE WESTERN COAST:
• The western coast borders the Arabian Sea.
• It is by & large a rocky coast.
• Characteristics Western Ghats:
• It rises steeply from the west coast.
• It orginates from Tapti river till Kanyakumari.
• Western Ghats are higher than the Eastern Ghats and have an average height of 900 to 1100 m.
• Originating rivers: Godavari, Kaveri, Krishna, Thamiraparani & Tungabhadra rivers.
THE WESTERN COAST:
• The western coast borders the Arabian Sea.
• It is by & large a rocky coast.
• Characteristics Western Ghats:
• It rises steeply from the west coast.
• It orginates from Tapti river till Kanyakumari.
• Western Ghats are higher than the Eastern Ghats and have an average height of 900 to 1100 m.
• Originating rivers: Godavari, Kaveri, Krishna, Thamiraparani & Tungabhadra rivers.
5. The Island group:
• India has many small and large islands along the coast of the mainland.
• These are included in the coastal island group.
• India has two large group of islands, one each in Arabian sea and in the Bay of Bengal.
• The islands in the Arabian Sea are known as Lakshadweep whereas the islands in the Bay of Bengal are called the Andaman and Nicobar Islands.
•
• Most of the islands in Lakshadweep are atoll islands.
• They are small in extent and not very high.
• Islands in the Andaman group are mainly volcanic islands.
• They are large with hills in their interior parts of includes an island called Barren Island which has only active volcano in India.
• There are atolls in the Nicobar group too.
[ ] PHYSIOGRAPHY OF BRAZIL
[Visit the YouTube channel for better understanding: https://youtu.be/tHrYCVcXEo4]
• A large part is occupied by Highlands, plateaus and small mountains.
• No high and extending mountains.
• No wide plains except for the northern Amazon basin and in Southwest along the upper parts of Paraguay basin.
• Costal plains are also restricted in their expanse.
1. The Highlands
2. The Great Escarpment
3. The Coastal region
4. The plains
5. The Islands groups
• A large part is occupied by Highlands, plateaus and small mountains.
• No high and extending mountains.
• No wide plains except for the northern Amazon basin and in Southwest along the upper parts of Paraguay basin.
• Costal plains are also restricted in their expanse.
1. The Highlands
2. The Great Escarpment
3. The Coastal region
4. The plains
5. The Islands groups
1.The Highlands:
• An area of high or mountainous land / plateaus.
• The Brazilian Highlands or plateaus are extensive geographical region, covering most of the eastern, southern and central part of Brazil, in all approximately half of the country’s land area or some 4,500,00 km2, Elevation- 2891 m .
• The Southern Brazil is occupied by an extensive plateau.
THE CORE PART:
• Brazilian Highlands and Guyana highlands together form the Core of South American Continent.
• The main part of Guyana highlands is in Venezuela.
• It extends upto French Guiana.
• It covers the states of Roraima, Para and Amapa in the North.
LOWER PART OF THE HIGHLANDS:
• The highest peak of Brazil, Pico de Neblina is 3014 m high and lies on the borders between Brazil and Venezuela.
ALTITUDE:
• Regions to the east and south of the Brazilian highlands have an altitude of more than 1000m.
• But in other parts, the altitude is between 500-1000m.
• SLOPE:
• It gradually slopes towards North and slpoes are not very steep.
THE TRIBUTARIES OF AMEZON:
• Flowing through this region make rapids and waterfalls.
• The slopes are steep but not abrupt.
RIVERS:
• A number of rivers take off from the terminal portion of the highlands and flow northwards to meet Atlantic Ocean.
• Major rivers like Uruguay, Paraguay and Parana from the Southern slopes of highlands and enter Argentina.
• Its slope towards the east is steep and it appears in the form of an escarpment.
2. THE GREAT ESCARPMENT:
• Escarpment: a long, steep, slope, especially one at the edge of a plateau/ separating areas of land at different heights.
• It occupies a very small area.
• But the nature of its slope and the effect it has on the Climate makes a separate physiographic region.
• Because of the escarpment, the eastern side of the highlands is demarcated/ separated.
ALTITUDE:
• The altitude of the escarpment is 790m.
• The hight decreases in some regions.
• It is very steep from Sao Paulo to Porto Alegre.
• The escarpment acts as a barrier to the southeast Trade winds giving rise to the rainshadow area in the northeastern part of the highlands.
• The region to the north this area is called ‘Drought Quadrilateral.
3) THE COASTS:
• It has a coastline of about 7400 km.
• It is divided in to two parts namely Northern and eastern coasts.
EXTEND:
• The northern coast extends from Amapa province in the north to Rio Grande do Norte in the east.
• This is called as the North Atlantic Coast.
• The eastern coast extends towards the south.
CHARACTERISTICS:
• The Northern Coast is characterized by Mouths of many rivers including Amazon.
• This is low lying region.
• On this coast lie the Marajo island and Sao Marcos Bays.
• Marajo is a large coast island located between the mouths of River Amazon and River Tocantins.
• The eastern coast receives large number of smaller rivers.
• The only major river which meets the Atlantic ocean here is Sao Francisco.
• The Brazilian coast is characterized by a large number of beaches and sand dune (bank) complexes.
• The Brazilian coast is protected in some area by Coral reef [ an underwater ecosystem characterized by reef building corals.( marine invertebrates) reef sand bar / bank] and atoll islands (ring shaped islands)
4. THE PLAINS:
• The plains are restricted/limited/confined to two areas namely the Amazon basin in the north and Paraguay-Parana Source region in the southwest.
• Amazon plains are lying between the two highlands form the largest plain land ( Guyana and Brazilian Highlands)
• Its lying in the Northern parts of Brazil generally slope eastward.
EXTENSION:
• Amazon basin is quite wide in the west (about 1300 km) and it narrows eastwards.
• WIDTH: Its width is minimum where the Guyana Highlands and Brazilian highlands come closer. (240 km)
• As the river reaches Atlantic, the width increases.
CHARACTERISTICS:
1.These are mostly forested areas and largely inaccessible due to frequent flooding and dense undergrowth.
2. Most of the Amazon plains are covered by tropical rainforests. (tropical rainforests are rainforests that occur in areas of tropical rainforests climate in which there is no dry season – all months have an average precipitation of at least 60 mm.)
3. It is the world’s largest tropical rainforest, famed for its biodiversity.
It’s crisscrossed by thousands of rivers, including the powerful Amazon.
OTHER PLAINS:
• The other plains are located to the Southwestern part of the highlands.
• They form the source region of Paraguay and Parana rivers.
• The source region of Paraguay slopes towards the South and the source region of Parana slopes towards the Southwest.
PANTANAL:
• Pantanal is one of the world’s largest wetland ( land consisting of marshes/swams, saturated land)
• It lies towards the southwest part of the highland areas.
• It is a region of swamps ( A swamp is a forested wetland. Swamps are considered to be transition zone because both land and water play a role in creating this environment. Swams are vary in size and are located all around the world. The water of a swamp may be fresh water, brackish water or sea water) and marshes in north western Mato Grosso do Sul in Brazil and it extends in to Argentina too.
5. ISLANDS OF BRAZIL:
• The islands in Brazil can be classified into coastal islands and marine islands.
• Most of them have formed due to deposition.
• Marine islands were a part of the mainland.
• They are more than 300 km away from the mainland in the Atlantic Ocean.
• These are mostly rocky and they are the top of submerged mountains.
• The islands near the coast of the South Atlantic ocean are coral islands and they are called atolls.
[ ] DRAINAGE:
• The system of water or waste liquids flowing from somewhere into the ground of down pipes.
A COMPARATIVE NOTE ON THE BASINS OF GANGA AND AMAZON RIVER:
DRAINAGE OF BRAZIL:
Three major river Basins:
1. Amazon Basin
2. Paraguay -Parana system in the southwest.
3. Sao Francisco in the eastern part of Highland and others rivers at the coasts.
1. AMAZON BASIN:
1. Size of catchment area ( the area from which rainfall flows into river, lake or reservoir) of Amazon river is 70,50,00 sq.km.
2. It collects it headwaters ( a trubutary stream of a river close to or forming part of its source) from the eastern slopes of Andes Mountain in Peru.
3. Amazon river receives huge discharge (River discharge is the volume of water flowing through a river channel;measured at any given point in cubic meters per second)Its about 2 lakhs m3/S.
4. The result of huge water discharge is Amazon cleans, removes or washes off the load supplied to it doesn't deposit and sediments at the river mouth.
5. Generally, a dense network of distributaries ( a branch of river that doesn't return to the main stream after leaving it. ( as in delta) dound at the mouth of river but such distributaries are not found at the mouth of Amazon.
6. Instead of it, a series of islands developed/ formed along the mouth of Amazon beyond the coast line into the Atlantic Ocean.
7. The width of Amazon channel at its mouth is 150 km.
8. Most of the course ( the route/ direction followed by ships or river) is suitable for navigation.
2. PARAGUAY- PARANA SYSTEM:
1. LOCATION:
• Rivers Paraguay and Parana are located in the Southwestern part of Brazil.
2. CATCHMENT:
• Both the rivers form the catchment of river Rio-de-la Plata in Argentina. [ River Plata includes areas of Southeastern Bolivia, Southern and central Brazil, the entire country of Paraguay, most of Uruguay and Northern Argentina.
3. HEADWATERS:
• River Paraguay, river Parana and river Uruguay in Extreme south of the highlands collect their headwaters from the southern portion of the highlands.
3. SAO FRANCISCO:
• It is the third important river of Brazil.
• It is a large river in Brazil, with a length of 2914 km.
• It is the longes river that runs entirely in Brazilian territory and the fourth longest in South America overall in Brazil.
• The entire basin of this river is within Brazil.
• It originates in the Canastra mountain range.
• It occupies the eastern portion of the highlands.
• It flows toward north for a distance of about 1000 km over the plateau and then takes a sharp eastward turn to enter the coastal strip along the Atlantic Ocean.
• The river is navigable for a distance od about 250 km in its downstream reaches.
COASTAL RIVERS:
• It has a number of short coastal rivers attain significance because the coastal area is densely populated.
• River Paraniba and River Itapecury flowing northward meet the North Atlantic Ocean.
• The river that enter South Atlantic Ocean collect their headwaters along the escarpment.
• River Paraguaco enters the Atlantic Ocean near Salvador town.
[ ] INDIA
[ ] DRAINAGE OF INDIA:
• Rivers are classified according to their source region into Himalayan and Peninsular rivers.
• HIMALAYAN DRAINAGE
• Major rivers in the Himalayas originate from various glaciers.
• The discharge of water increases in summer due to glaciers melt.
• It floods during monsoons too.
• These are perennial (everlasting, continuing) rivers.
• The Himalayas are drained by 19 rivers, of which Indus river system and Ganga river system cover the drainage.
• THE RIVER INDUS:
• Indus and its tributaries Jhelum, Chenab, Ravi and Satluj drain the Western Himalayas.
• They flow through the state of Jammu and Kashmir.
• They flow almost parallel to each other.
• A major tributary of river Indus is the Satluj originates near Man Sarover and flows westwards.
• Punjab plains have formed due river and its tributaries.
• Indus further flows through Pakistan and then meets the Arabian sea.
• The indus is a transboundary river of Asia and trans- Himalayan river of South and Central Asia.
• The 3,180 km (1980 miles) river rises in Western Tibet, flows north west through the disputed region of Kashmir.
• THE RIVER GANGA:
• It originates from the Gangotri glacier and crosses the Himalayas to become and east flowing river.
• Thw Ganges is transboundary river of Asia which flows through India and Bangladesh (Padma).
• The 2525 km (1569 mi) river rises in the western in the Indian State Uttarakhand.
• It flows south and east through the Gangetic plain of North India, receiving the right bank tributary, the Yamuna..
• YAMUNA: It originates at Yamunotri, is a mojor tributary of Ganga.
• BRAHMAPUTRA:
• Another major tributary of the Ganga flows through the northern part of the Greater Himalayas, crosses the Himalaya to enter India.
• When it flows through the Himalaya it is called Tsang Po.
• When it crosses the Himalayas, it is called Fihang and its eastward flow thereafter is called as Brahmaputra.
• Ganga meets its tributaries, hence its discharge increases.
• Ganga receives Brahmaputra as its tributary in its lower reaches in Bangladesh.
• Ganga delta: The huge volume of water and huge deposition has led to the formation of a large delta.
• Tributaries: Besides these Himalayan rivers, Ganga receives a number of tributaries from Peninsula like Chanbal, Ken, Betawa, Shon, Damodar etc.
• PENINSULA RIVERS:
• Its divided into east-flowing meeting the Bay of Bengal and west-flowing meeting thw Arabian Sea.
• The western Ghats are called water divide in Peninsula.
• The western Ghats are called a water divide because they act as a divide between the west flowing rivers meeting the Arabian sea and east flowing rivers meeting the Bay of Bengal.
• The peninsular rivers are rainfed ( relies on rainfall water) rivers so rarely face the problem of floods.
• They are seasonal in nature.
• In Peninsular India, the west-flowing rivers are smaller and less in number campared to east-flowing rivers.
• THE WEST FLOWING:
• The major west-flowing rivers in Peninsular India are the Narmada and Tapi.
• The west flowing rivers occupying the area between the Western Ghats and the Arabian Coastline are short in length but swift.
• This condition of short and swift river system exists in the states of Kerala, Karnataka, Maharashtra and Southern Gujrat.
• NORTHWARD FLOWING RIVERS:
• Northward flowing river system flowing in to the Gulf Of Khambhat.
• These river systems are Tapi, Narmada, Mahi and Sabarmati.
• Tapi and Narmada flow slowly through rift
valleys.
• Mahi River flows from North East to South West direction whereas River Sabarmati collecting its headwaters from the southern slopes of Aravali ranges flows in somewhat North-South direction.
• Another noteworthy river forming the catchment of Arabian Sea is River Luni.
• It originates along the western slopes of Aravali range and flows in somewhat northeast to southwest direction and flows into Gulf of Kutchch.
[ ] Rivers meeting the Bay of Bengal :
• Most of the area of the Peninsula is drained
• by the rivers flowing towards Bay of Bengal.
• The important river systems of this group are
• Mahanadi, Godavari, Krishna and Kaveri.
• Mahanadi basin occupies the northeastern
• part of the Peninsula.
• Godavari, Krishna and Kaveri originate in the eastern slopes of the Western Ghats.
• River Godavari is the second largest river system of India in terms of the catchment area.
• The Godavari is India's second longest river after the Ganga and third largest in India, drains about 10% of India's total Geographical area. Its source is in Trimbakeshwar, Nashik, Maharashtra.
• It flows east for 1465 km, draining the stated of Maharashtra, Telangana, Andhra Pradesh, Chhatisgarh and Odisha.
• To the south of Godavari is located the
basin of River Krishna.
• The Krishan River is a river in Deccan Plateau, and the third longest river of India, after Ganga &Godavari and the fourth largest in terms of water inflows and river basin area in India after The Gangs Indus and Godavari. IT IS 1400 KM (870MI ) Long. Its length in Maharashtra is 282 km.
• It major tributaries are Bhima and Tungbhadra.
• River Kaveri Basin flows through the states of Karnataka and Tamil Nadu.
• It is one of the major rivers of Peninsula. It is a river
• that has been harnessed for irrigation since a long time.
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