Southern Madagascar - February 19th, 2009

Several sediment-loaded rivers run from the central highlands of Madagascar to the Mozambique Channel.

The Mangoky River, top left, is 564 kilometers long (350 mi). It flows generally in a westerly direction out of the highlands, crosses the southern extension of the Bemaraha Plateau, reaches the coastal plain and its delta, and enters the Mozambique Channel north of the city of Morombe.

Most of Madagascar has undergone serious deforestation during the last 40 years, which has led to extreme soil erosion in the Mangoky River basin, as evidenced by the many sandbars located within the river channel.

Silt-laden, greenish-tan Lake Ihotry is clearly discernible south of the river. It is a closed saline lake whose area varies seasonally, from 96 km² to 112 km².

Between the lake and the coast is a rather large, whitish area of sand interspersed with silt-laden ponds.

The southern portion of the delta is dominated by successive barrier island and spit formation. In contrast, the northern, protected portion of the delta is dominated by tidal passes and mangrove swamps

Further south, the Onilahy River, in the province of Toliara, flows down from the hills near Betroka to the Mozambique Channel.

Tags: Bemaraha Plateau Betroka Deforestation Lake Ihotry Madagascar Mangoky River Morombe Mozambique Channel Onilahy River Sandbars Sediments Toliara |