*India: The Land of Diversities*
India Physiographic divisions
1๏ธโฃ Northern Mountain Ranges
2๏ธโฃ Northern Great Plains
3๏ธโฃ Peninsular plateau
4๏ธโฃ Coastal plain -Islands
๐ Northern Mountain Ranges
๐ In Northern mountain region there are three mountain ranges
They are:-
A) Trans Himalayas
B) Himalayas
C) Eastern Highlands
A) Trans Himalayas
โ๐ป Trans Himalayas include *Karakoram, Ladakh, and Zaskar* mountain ranges.
โ๐ป Mount K2 (8661m) also known as Godwin Austin, the highest peak in India, is in the Karakoram range. -The average height of the Trans Himalayas is 6000 meters.
B) Himalayas
โ๐ป The Himalayan mountain range forms an are shaped physical division extending between the north-west trans himalayas and the south-east eastern highlands.
โ๐ป These mountain ranges have a length of about 2400 kilometers.
โ๐ป Many of the world's highest peaks are situated here.
โ๐ป The height of these mountains tend to decrease towards the east.
๐ Himalayan ranges are divided in to three. They are:-
โป๏ธHimadri,
โป๏ธHimachal,
โป๏ธSiwaliks.
๐ *Himadri*
โป๏ธ The highest mountain range.
โป๏ธ Average altitude is 6000 meters.
โป๏ธ Origin of the rivers Ganga and Brahmaputra.
.
โป๏ธHas a number of peaks above 8000 meters (Eg: Kanchenjunga, Nandadevi)
๐ *Himachal*
โป๏ธSituated to the south of the Himadri.
โป๏ธAverage altitude is 3000 meters.
โป๏ธThe hill stations like Shimla, Darjeeling, etc. are situated in the southern slopes of this range.
๐ *Siwaliks*
โป๏ธ Situated to the south of the Himachal.
โป๏ธAverage altitude is 1220 meters.
โป๏ธ As the Himalayan rivers cut across this range, its continuity breaks at many places.
โป๏ธBroad flat valleys seen along these ranges are called Duns. (Eg: Dehradun).
๐ *Human life in the lap of the Himalayas*
โ๐ป The major means of livelihood is animal rearing that depends purely on the grasslands here.
โ๐ป Sheep are commercially reared in Kashmir and Himachal.
โ๐ป Potato, barley, and saffron, fruits like apple and orange are cultivated in Siwalik valleys.
โ๐ป The largest production of tea in India comes from Assam mountain ranges.
โ๐ป Hill stations like Shimla, Darjeeling, Kulu, Manali, etc. are situated here.
*Eastern Highlands*
โป๏ธThis region which is at an altitude of 500 to 3000 meters is also known as Purvachal.
โป๏ธCherrapunji, the place receiving the highest rainfall in the world is situated here.
โป๏ธThis region is covered by dense tropical rain forests.
Major mountains in Eastern Highlands.
(1) Patkai Bum-Nagaland
(2) Naga hills-Nagaland
(3) Garo, Khasi, and Jaintia hills-Meghalaya
(4) Mizo hills-Mizoram
*Significance of the Northern Mountains*
โป๏ธHave been protecting us from foreign invasions from the north since ancient times.
โป๏ธ Block the monsoon winds and cause rainfall throughout North India.
โป๏ธ Caused the emergence of diverse flora and fauna.
โป๏ธSource region of rivers.
Indian rivers.
*Northern Great Plains*
โฝDuring the formation of the Himalayas, a huge depression of more than 2000 metre depth took shape along the south parallel to the Himalayas.
โฝThis extensive plain took shape as a result of the continuous deposition by the rivers flowing down from the Himalayas for thousands of years.
โฝThis plain, extending over seven lakh square kilometres and with kilometres of thick sediments, is one among the few extensive alluvial plains of the world.
โฝThis plain is generally known as the Indus-Ganga-Brahmaputra plain.
โฝThe highly fertile alluvial soil is a characteristic feature of this plain.
โฝThe granary of India.
โฝA variety of crops such as wheat, maize, rice, sugar cane, cotton, pulses, etc. Cultivated in Northern Great Plains.
โฝThis region is known as the granary of India.
โฝThe Northern Great Plain is one of the most densely populated regions in the world.
๐ *Thar Desert*
โ๐ป Rainfall is scarce along the western parts of the northern plains.
โ๐ป That is why most regions in Rajasthan are deserts.
โ๐ป This desert is known as Thar Desert.
โ๐ป River Luni and the long vanished river Saraswathy have had significant role in the formation this portion of the plain.
โ๐ป Dry and salty desert soil is found in this Region.
โ๐ป Thorns and bushes form the natural vegetation here.
What are the main crops cultivated in Rajasthan.
-Bajra,
-Jowar,
โ๐ป These crops require very little amount of water to grow.
โ๐ป Here cultivation is done mainly with the help of irrigation.
๐ *The Peninsular Plateau*
๐ Entire portions of Madhya Pradesh, Jharkhand and Chhattisgarh as well as parts of Maharashtra, Karnataka, Tamil Nadu, Telengana, Odisha and West Bengal together form a plateau known as the *peninsular plateau*.
๐ The peninsular plateau made of hard crystalline rocks forms the oldest and the most extensive physical division of India.
๐ It extends about 15 lakh square kilometres.
๐ The highest peak in this region is the Anamudi (2695 m) situated in the Idukki district of Kerala.
๐ As the peninsular plateau holds numerous deposits of diverse minerals, this region can be termed as the *Store house of minerals*.
๐ The trees found in this region are teak, sal, sandalwood, bamboo, etc.
๐ Black soil is extensively found in this region made of igneous rocks, named basalt.
๐ As this soil is best suited for cotton cultivation, it is also called *black cotton soil*.
๐ *Red soil also formed by the weathering of igneous and metamorphic rocks is comparatively less fertile*.
๐ The presence of iron gives red colour to this soil.
๐ *Peninsular Rivers*
โฝThe rivers originating from the elevated regions of the peninsular plateau are known as peninsular rivers.
โฝPeninsular Rivers are divided in to two:-
โฝWest flowing rivers- Narmada & Tapti.
โฝEast flowing rivers-Mahanadi, Godavari, Krishna & Cauvery.
โฝGodavari is the longest among the peninsular rivers.
โฝWaterfalls are common in most of the peninsularrivers.
โฝThe highest among these is the Jog Falls (225 metres).
โฝCotton, pulses, groundnut, sugarcane, maize, ragi, chilli, etc., are the major agricultural crops of this region.
โฝIron ore, coal, manganese, bauxite, limestone, etc. are the major minerals found here.
โฝHence agriculture, mining, and mineral based industries are the major economic activities.
๐ *Coastal plain of India*
โ๐ป The approximate length of this coast line is 6100 kilometres extending from the Rann of Kutchh in Gujarat to the Ganga-Brahmaputra delta.
โ๐ป The coastal plain of India can be divided into two.
They are:
โ
*Western coastal plain*
โฝWestern coastal plain
Between the Arabian Sea and the
Western Ghats.
โฝFrom the Rann of Kutchh to Kanyakumari.
โฝComparatively narrow
Can be divided into Gujarat coast, Konkan coast, and Malabar coast.
โฝBackwaters and esturies are seen.
โ
*Eastern coastal plain*
โฝBetween the Bay of Bengal and theEastern Ghats.
โฝFrom the Sundarban delta region to Kanyakumari.
โฝComparatively wide.
โฝCan be divided into north Zircar plain and Coromandal coast.
โฝDelta formation takes place.
โMain occupation of the
people in the coastal plains.
โฝFishing
โฝTourism
โฝRice and coconut are the major agricultural crops along the west coast.
๐ *Major islands in India*
1๏ธโฃ *The Lakshadweep islands*
2๏ธโฃ *The Andaman and Nicobar islands* .
*The Lakshadweep islands*
โฝ The Lakshadweep islands are situated in the Arabian Sea at a distance of about 300 kilometers off shore from Kochi.
โฝ There are 36 islands in this island group, of which only 11 are inhabited.
โฝ Kavarathi is the capital of Lakshadweep.
โฝ Lagoons, sandy beaches and coral reefs are the specialities of the Lakshadweep island group.
โฝ Fishing and tourism are the major sources of income.
*The Andaman and Nicobar islands*
โฝ The Andaman and Nicobar islands include about 200 islands of Andaman group and 19 islands of Nicobar group.
โฝ Most of these islands are not inhabited.
โฝ Many of them have dense forests.
โฝ The only volcano in India is situated in the Barren Island here.
โฝ Port Blair is the capital of Andaman and Nicobar islands.
*Himalayan rivers*
โป๏ธHimalayan rivers
Originate from the Himalayan mountain
ranges.
โป๏ธExtensive catchment area.
โป๏ธIntensive erosion
โป๏ธHigh irrigation potential.
โป๏ธNavigable along the plains.
*Peninsular rivers*
๐ธOriginate from the mountain ranges in the peninsular plateau.
๐ธComparatively smaller catchment area.
๐ธIntensity of erosion is less.
๐ธLess irrigation potential.
๐ธ Potential for inland navigation is low
โ๏ธ The factors influencing the climate of India.
โป๏ธLatitude
โป๏ธPhysiography
โป๏ธNearness to sea
โป๏ธAltitude
โป๏ธMountains
โป๏ธWinds
๐ธThe seasons in India can be generally classified into four.
1๏ธโฃ *Cold weather season In India* (Winter)
โป๏ธIndia experiences winter when the position of the sun is over the southern hemisphere.
โป๏ธMost places in India experience intense fog and snowfall occurs in the valleys of the Himalayas during this season.
โป๏ธThe months of December, January, and February experienced cold weather in India.
โป๏ธDuring the cold weather season days are generally warm and nights are severely cold in North India.
โป๏ธSnowfall is a common phenomenon in the hill stations like Manali and Shimla.
โWhat is Western Disturbance.
โป๏ธThe cyclones originating in the Mediterranean Sea during winter, gradually shifts towards the east and reaches India.
This causes winter rainfall in the northern plains, especially in the Punjab region.
The phenomenon is called *western disturbance* .
2๏ธโฃ *Hot weather season* (Summer)
โป๏ธIndia experiences hot weather when the sun is over the northern hemisphere.
โป๏ธIn the months of March, April and May experienced Summer season in India.
โป๏ธIt is in Barmer in western Rajasthan that the highest temperature of summer is felt.
โป๏ธLoo, mango showers, etc. are some local winds experienced in India during this season.
3๏ธโฃ *South west monsoon season*
โป๏ธWhen the sun is over the northern hemisphere, North Indian regions experience intense low pressure.
โป๏ธIn the months of June, July, August and September India experience south west monsoon season.
โป๏ธOwing to the high pressure over the oceans, wind blows from high pressure to low pressure regions, that is, from the Indian Ocean to the Indian sub-continent.
โป๏ธAs the winds deflect towards right due to coriolis effect, they reach India as southwest monsoon winds.
โป๏ธBecause of the peculiar shape of the Indian peninsula, the southwest monsoon winds bifurcate into two branches on entering the land.
๐ *Arabian Sea branch*
๐ *Bay of Bengal branch*
โป๏ธThe Arabian Sea branch that reaches the coast of Kerala by early June causes heavy rainfall here.
โป๏ธThe Arabian Sea branch of south west monsoon that reaches the coast of Kerala by early June causes heavy rainfall here.
โป๏ธThen it advances to the states of Karnataka, Goa, Maharashtra, and Gujarat and causes rainfall in the western parts.
โBy what name is the southwest monsoon rain known in Kerala?
- *Edavappaathi*
๐ *Bay of Bengal branch*
โป๏ธThe Bay of Bengal branch of the monsoon advances northward by absorbing more moisture from the Bay of Bengal.
โป๏ธOn reaching West Bengal, crossing the Sundarban delta, it bifurcates into two branches.
โป๏ธOne branch reaches the northeastern states through the Brahmaputhra plains and causes heavy rainfall there.
โป๏ธThe other branch enters the Ganga plains and causes rainfall in West Bengal, Bihar, Uttar Pradesh, etc.
โป๏ธThis branch merging with the Arabian Sea branch in the Punjab plains advances north further and causes heavy rainfall along the foothills of the Himalayas.
4๏ธโฃ *Retreating monsoon season* (North East Monsoon)
โป๏ธBy the end of September, as the sun apparently shifts towards the southern hemisphere, intense high pressure develops over the northern plains.
โป๏ธComparatively low pressure over the Indian Ocean causes wind to blow from the northern part of India towards the Indian Ocean.
โป๏ธThese winds known as north-east monsoon winds are dry winds that do not generally cause any rain in India.
โป๏ธThis season termed as north east monsoon.
โป๏ธThis season is actually a transition period between the rainy season and the forth coming winter
โป๏ธThis season experienced during the months of October and November.
โป๏ธThis season termed as north east monsoon.
โป๏ธThis season is actually a transition period between the rainy season and the forth coming winter.
โป๏ธThis season experienced during the months of October and November.
โป๏ธThis is the main rainy season of Tamil Nadu.
๐ *October heat*
โป๏ธThe days in October and November unbearable due to high temperature and humidity.
โป๏ธThis phenomenon is known as October heat.
โBy what name is the northeast monsoon rain known in Kerala?
*Thulaavarsham*