India: Relief Features

India, the 7^th largest country in the world and it has a vast longitudinal extent. India is located between 687’E and 9725’E. The longitudinal difference between the easternmost (Arunachal Pradesh) and westernmost (Gujarat) limits is approximate 30

As we know that the sun takes 4 minutes to cross 1 longitude. (One rotation completed by earth in 24 hours (1440 min). Total no. of longitudes is 360. Therefore 1440 ÷ 360= 4min)

So, to cross 30 longitudes, it will take 120 minutes or 2 hours.

To avoid confusion of time difference along the longitudes 8230’E is considered as the Standard Meridian of India. Therefore, all the places in India have the same time.

The Great Himalayas are the great climatic moderator for the Indian subcontinent. They act as a barrier against the chilling Arctic winds. They deflect the Arctic winds back to China and Siberia. They also prevent Jetstreams from interfering the climatic conditions of India. Hence, they prevent North India from becoming a cold desert. It also traps the rain-bearing monsoon winds from escaping to the Asia continent and forcing them to rain in India.

The Himalayan ranges run in the west-east direction with a distance of about 2400 kms. The Himalayas comprise three parallel ranges. These ranges are separated with deep valleys and extensive plateaus. They extend from Jammu and Kashmir, Himachal radish, Uttarakhand, Sikkim, Arunachal Pradesh, Meghalaya, Nagaland, Manipur, Mizoram, Tripura.

Following are the major physiographic divisions of India-

i) The Great Himalayas

ii) The Northern Plains

iii) The Western Desert

iv) The Peninsular Plateau

v) The Coastal Plains

vi) The Island groups

The contrasting features of the Himalayan region and of the Peninsular plateau are as follows-

The Himalayas has a profound influence on Indian agriculture. Following are the ways in which the Himalayas influence Indian agriculture –

a. Rivers – Agriculture is the mainstay of many people living in the northern region. The Himalayas are the source of water to the three major river systems namely, the Indus river system, the Ganga river system and the Brahmaputra river system. These three river systems altogether with numerous tributaries and distributaries have a large catchment area that they drain and provide life-giving water to the people living in the region. The agricultural lands are irrigated by the water of these rivers.

b. Rains – the Himalayas prevent the rain-bearing monsoon winds from escaping to Asia continent by obstructing its path and forcing them to rain in India. Monsoons are the main source of water/irrigation in India. Its failure results in drought and famine in many parts of India.

c. Fertile soil –River originating in the Himalayas carry loads of fertile alluvium while sculpting the valleys in its upper course. These sediments are deposits on the banks of the river when the river enters the plain and thus each year fertile soil deposited by the river which promotes agricultural production in the plain and delta region.

Indo-Gangetic plains are the most populated region of India. There are many factors responsible for it, they are –

a. Perennial supply of water- Availability of water throughout the year make agricultural activities possible all through the year and more than one crop cycle in a year possible to support the population.

b. A strong network of road and rail - Gangetic plains have a strong network of road and rail network that connect it to all the parts of the country. The comparatively flat surface of the Indo-Gangetic plains provides the ideal conditions to construct roads and lay railway lines.

c. Many agro-based industries are located in this region. Providing work to the people and attracting people from other parts in the region.

(i) Barren Islands (India)

(ii) Pakistan, Srilanka, Nepal, Bangladesh, Bhutan, Myanmar

(iii) Gujarat, Rajasthan, Madhya Pradesh, Chhatisgarh, Jharkhand, West Bengal, Tripura and Mizoram

(iv) 37⁰6’ N

(v) 8⁰4’ N

(vi) 68°7'E and 97°25'E

(vii) Kanyakumari

(viii) Palk Straits

(ix) Delhi, Chandigarh, Puducherry, Dadra Nagar Haveli, Daman and Diu, Lakshadweep, Andaman and Nicobar.

The similarities between the Eastern and Western Coastal plains are as follows –

a. Both of the coastal plains are bordered by the water body.

b. Both are part of the peninsular block.

c. Both lie between the Deccan plateau and the water bodies.

d. Both fall under the same climatic zone.

The points of differences between the two are as follows –

The foremost and primary reason is the soil and relief. The plateau region is the oldest tectonic block of the Indian subcontinent. It has a highly eroded surface and mainly consists of hard rocks. Due to this reason, there is a very thin layer of soil in this region that too is not fertile and lack humus content.

The next important reason is the lack of availability of water throughout the year. The rivers of this region are rain-fed thus in summers they hardly have water to support agriculture in the region.