The Ganges Delta (also known as the Ganges-Brahmaputra Delta, the Sundarbans Delta or the Bengal Delta) is a river delta in the Bengal region of South Asia, consisting of Bangladesh and the Indian state of West Bengal. It is the world's largest river delta and it empties into the Bay of Bengal with the combined waters of several river systems, mainly those of the Brahmaputra river and the Ganges river. It is also one of the most fertile regions in the world, thus earning the nickname the Green Delta. The delta stretches from the Hooghly River east as far as the Meghna River. Geography The Ganges Delta has the shape of a triangle and is considered to be an "arcuate" (arc-shaped) delta. It covers more than 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 slow down in the estuary. Rivers carry these fine particles with them, even from their sources at glaciers as fluvio-glacial. Red and red-yellow laterite soils are found as one heads farther east. The soil has large amounts of minerals and nutrients, which is good for agriculture. It is composed of a labyrinth of channels, swamps, lakes, and flood plain sediments (chars). The Gorai-Madhumati River, one of the distributaries of the Ganges, divides the Ganges Delta into two parts: the geologically young, active, eastern delta, and the older, less active, western delta. Population Around 280 million (180 million Bangladesh & 100 million West Bengal, India) people live on the delta, despite risks from floods caused by monsoons, heavy run-off from the melting snows of the Himalayas, and North Indian Ocean tropical cyclones. A large part of the nation of Bangladesh lies in the Ganges Delta; many of the country's people depend on the delta for survival. It is believed that upwards of 300 million people are supported by the Ganges Delta; approximately 400 million people live in the Ganges River Basin, making it the most populous river basin in the world. Most of the Ganges Delta has a population density greater than 200/km2 (520 people per square mile), making it one of the most densely populated regions in the world. Wildlife Three terrestrial ecoregions cover the delta. The Lower Gangetic plains moist deciduous