Red Sediments Spill from Madagascar Rivers
Rusty red sediments flow into the Mozambique Channel from rivermouths on Madagascar’s west coast.
The Sofia River can be seen flowing into a bay near the center of the image, while the Betsiboka River (bottom left) empties its load of sediments into the Bombetoka Bay, forming a large delta.
The 525 kilometer-long Betsiboka River is distinct for its red-colored water, which is caused by river sediments. The river carries an enormous amount of reddish-orange silt to the sea. Much of this silt is deposited at the mouth of the river or in the bay.
It is dramatic evidence of the catastrophic erosion of northwestern Madagascar. Removal of the native forest for cultivation and pastureland during the past 50 years has led to massive annual soil losses, approaching 250 metric tons per hectare (112 tons per acre) in some regions of the island, the largest amount recorded anywhere in the world.