Indo-Gangetic Plain

Overview :

The Indo-Gangetic Plain, also known as the North Indian River Plain, is a 0.70-million km² (172-million-acre) fertile plain encompassing northern regions of the Indian subcontinent, including most of northern and eastern India, the eastern parts of Pakistan, virtually all of Bangladesh and southern plains of Nepal. The region is named after the Indus and the Ganges rivers and encompasses a number of large urban areas. The plain is bound on the north by the Himalayas, which feed its numerous rivers and are the source of the fertile alluvium deposited across the region by the two river systems. The southern edge of the plain is marked by the Chota Nagpur Plateau. On the west rises the Iranian Plateau. Many developed cities like Kolkata, Delhi, Karachi and Dacca are located in the Indo-Gangetic Plain .

Geography :

The Indo-Gangetic Plain is divided into two drainage basins by the Delhi Ridge; the western part drains to the Indus, and the eastern part consists of the Ganga–Brahmaputra drainage systems. This divide is only 350 metres above sea level, causing the perception that the Indo-Gangetic Plain appears to be continuous from Sindh in the west to Bengal and Assam in the east.

A thin strip between the foothills of the Himalayas and the plain, the Bhabar is a region of porous ground consisting of boulders and pebbles that have washed down from the mountains. It is not suitable for crops and is forested. The streams disappear underground here.

Below the Bhabar lie the grasslands of Terai and Dooars. The many tributaries of the Indus and Ganges divide the plain into doabs, tongues of land that extend to where the tributaries meet. Close to the rivers is khadar land of new alluvium that is subject to flooding. Above the flood limit, bangar land is older alluvium deposited in the middle Pleistocene.

The annual rainfall increases from west towards the east. The Lower Ganges Plains and the Assam Valley are more verdant than the middle Ganga plain. The lower Ganga is centered in West Bengal, from which it flows into Bangladesh. After joining the Jamuna, a distributary of Brahmaputra, both rivers form the Ganges Delta. The Brahmaputra rises in Tibet as the Yarlung Zangbo River and flows through Arunachal Pradesh and Assam, before crossing into Bangladesh.

Some geographers subdivide the Indo-Gangetic Plain into several parts: the Gujarat, Sindh, Punjab, Doab, Rohilkhand, Awadh, Bihar, Bengal and Assam regions.

Roughly, the Indo-Gangetic Plain stretches across:

the Jammu Plains in the north;

the Punjab Plains in eastern Pakistan and northwestern India;

the Sindh Plains in southern Pakistan;

the Indus Delta in southern Pakistan and western India;

the Ganga-Yamuna Doab;

the Rohilkhand (Katehr) Plains;

the Awadh Plains;

the Purvanchal Plains;

the Bihar Plains;

the North Bengal plains;

the Ganges Delta in India and Bangladesh;

and the Brahmaputra Valley in the east.

The fertile Terai region is spread across Southern Nepal and Northern India along the foothills of the Himalayas. The rivers encompassed are the Beas, the Chambal, the Chenab, the Ganga, the Gomti, the Indus, the Ravi, the Sutlej and the Yamuna. The soil is rich in silt, making the plain one of the most intensely farmed areas of the world. Even rural areas here are densely populated.

The Indus–Ganga plains, also known as the "Great Plains", are large floodplains of the Indus, Ganga and the Brahmaputra river systems. They run parallel to the Himalaya mountains, from Jammu and Kashmir and Khyber Pakhtunkhwa in the west to Assam in the east and draining most of Northern and Eastern India. The plains encompass an area of 700,000 km² (270,000 sq mi) and vary in width through their length by several hundred kilometres. The major rivers of this system are the Ganga and the Indus along with their tributaries; Beas, Yamuna, Gomti, Ravi, Chambal, Sutlej and Chenab.

The Indus-Ganga belt is the world's most extensive expanse of uninterrupted alluvium formed by the deposition of silt by the numerous rivers. The plains are flat and mostly treeless, making it conducive for irrigation through canals. The area is also rich in ground water sources. The plains are the world's most intensely farmed areas. The main crops grown are rice and wheat that are grown in rotation. Others include maize, sugarcane and cotton. The Indo-Gangetic plains rank among the world's most densely populated areas with a total population exceeding 400 million.