Class 7 Geography

Life in Subtropics

The Ganga-Brahmaputra basin is formed in the Indian subcontinent by tributaries of rivers Ganga and Brahmaputra. The basin lies in the sub-tropical region that is situated between 10° N to 30° N latitudes.

Some of the tributaries of the river Ganga are: Ghaghra, Son, Kosi, Chambal and Gandak. The main features of this basin are the plains of the Ganga and the Brahmaputra, the mountains and the foothills of the Himalayas and the Sundarbans Delta. Ox-bow lakes dot the plain area.

The Subtropical Region


The main climate here is the monsoon climate. Monsoons bring rains between mid-June and mid-September. The summers are hot and winters cool.

Topography and population

The basin has a varied topography. The environment plays a vital role in distribution of population. The mountain areas with steep slopes have sparse population because of inhospitable terrain. The plain area is densely populated because it is the most suitable for human habitation. The soil is highly fertile in the plains.

People of the area and their occupation

Agriculture is taken up as the main occupation where flat land is available to grow crops. The main crop is paddy. The staple diet of people is fish and rice. Since it requires sufficient water, it is grown in areas where rainfall is high. The other crops that are grown include wheat, maize, millet and gram. Cash crops such as sugarcane and jute are also grown. Tea plantations are found in West Bengal and Assam. Banana plantations are seen in the plains. In Bihar and Assam, silk is produced by rearing silkworms. Crops are grown on terraces of the hills that have gentle slopes.


The landforms influence the vegetation of the area. In the Ganga–Brahmaputra plain, tropical deciduous trees grow, along with teak, sal and peepal. Brahmaputra plain has thick bamboo groves. The delta is covered with mangrove forests. Since the climate is cool and the slopes are steep in parts of Uttarakhand, Sikkim and Arunachal Pradesh, coniferous trees like pine, deodar and fir are found.


There is a wide variety of wildlife in this basin. The common animals are monkeys, tigers, deer and elephants. The Brahmaputra plain has one-horned rhinoceros. In the delta area, Bengal tiger, crocodiles and alligator are found. There is abundant aquatic life too. Rohu, catla and hilsa are the most popular varieties of fish.

Development of the basin

The Ganga-Brahmaputra plain has many big towns and cities like Allahabad, Kanpur, Lucknow, Varanasi, Patna and Kolkata. The river is getting polluted because of industrial wastes and wastewater from these cities. All the modes of transport are well developed in this area. The plain area has a good network of roadways, railways and a large number of airports. The transport, particularly along the rivers is an effective means of waterways transport. Kolkata is an important port on the River Hoogly.

Tourism is another major activity of this basin. Some of the tourist spots in this area are listed below:

LocationTourist Attractions
AgraTaj Mahal
Prayagraj (Allahabad)Confluence of rivers Ganga and Yamuna
Uttar Pradesh and BiharBuddhist Stupas
AssamKaziranga, Manas Wildlife Sanctuary
Arunachal PradeshDistinct tribal culture


River's Mouth: The place where a river flows into another body of water.

Tributaries: These are the small rivers that join the main river.

River Basin: The main river along with all its tributaries that drain an area forms the river basin. It is also called the catchment area.

Do You Know?

The population density of Uttarakhand is 159 per sq km, while that of Bihar is 880 per sq km and that of West Bengal is 904 per sq km.