This image shows a large part of the Brasilian Amazon Basin. The area is a lowlying valley nearly entirely covered by tropical rainforest. The Amazon river is the world's largest river in terms of volume of water discharged into the sea. The river's network also forms the world's largest drainage system, comprehending about 1100 rivers. The tributaries are very often referred to as "white" or "black" rivers. White rivers (their actual colour is yellowish) often rise in the Andes, and their consistence results from heavy loads of mud and silt. Black rivers on the contrary rise in rocky basements from where no or little sediment is carried along. A beautiful example of the confluence of the Amazons main "white" and "black" river, the Solimões River and the Rio Negro converging as the Amazon River can clearly be seen on this image. A particularity of the Amazon River, is its very few settlements along the river's banks, in contrast to the usual large port, transport and industrialized cities along important waterways. Among the only three sizable cities that were settled on the Amazon banks, is Manaus on the right of the image, just north to the confluence. On the left of the image from top to bottom a main road can be distinguished, mainly by its settlements around it (especially on the upper part of the image). Rainforests throughout the world are being destroyed at an alarming rate and this should be a big concern as they are essential to life on a global scale. Unlike other forests, rainforests do not grow back once they are destroyed and its soil is not good for continued agricultural use.