It covers more than 105,000 km2 (41,000 sq mi) and lies mostly in Bangladesh and India, with rivers from Bhutan, Tibet, and Nepal draining into it from the north.
Most of the delta is composed of alluvial soils made up by small sediment particles that finally settle down as river currents slowdown in the estuary.
The Ganges–Brahmaputra basin has tropical deciduous forests that yield valuable timber: sal, teak, and peepal trees are found in these areas.
Birds found in the delta include kingfishers, eagles, woodpeckers, the shalik (Acridotheres tristis), the swamp francolin (Francolinus gularis), and the doel (Copsychus saularis).
The enormous sediment supply from the Himalayan collision has extended the delta about 400 kilometres (250 mi) seaward since the Eocene.
The sediment thickness southeast of the edge of the paleoshelf beneath the Ganges Delta can exceed 16 km (9.9 mi).
[6] Approximately two-thirds of the Bangladesh people work in agriculture and grow crops on the fertile floodplains of the delta.
[7] In the last decades of the 20th century, scientists helped the poor people of the delta to improve fish farming methods.
Arsenic is a naturally occurring substance in the Ganga Delta that has detrimental effects on health and may enter the food chain, especially in key crops such as rice.
The Guinness Book of World Records estimated the total loss of human life from the Bhola cyclone at 1,000,000.
The Bangladesh government asked for $900 million to help feed the people of the region, as the entire rice crop was lost.
[12][13][14] Debjani Bhattacharyya has shown how Calcutta was constructed as an urban centre through tracing ecological changes wrought upon by colonial powers involving land, water and humans throughout the mid-18th to the early 20th centuries.
[15][16] In terms of recent scholarship that focuses more on the eastern part of the Bengal/Ganges Delta, Iftekhar Iqbal argues for the inclusion of the Bengal Delta as an ecological framework within which to study the dynamics of agrarian prosperity or decline, communal conflicts, poverty and famine, especially throughout the colonial period.
One of the greatest challenges people living on the Ganges Delta may face in coming years is the threat of rising sea levels caused by climate change.
An increase in sea level of 0.5 metres (1 ft 8 in) could result in six million people losing their homes in Bangladesh.