Betsiboka River Delta (16S, 46E Madagascar)

This is a good image of the Betsiboka River developing into an estuary, the long Bay of Bombeteka in Madagascar. At 587000 sq. km (227000 sq. mi) Madagascar is the world’s fourth largest island, and is located off the tropical southwest coast of Africa. Politically, Madagascar is the Malagasy Republic, an independent nation with a democratic government. Though economically poor, Madagascar is famous for its wide variety of exotic animals, especially of marsupials and chameleons. The Betsiboka River, seen here, is one of Madagascar’s main waterways, running south-to-north and draining into the Indian Ocean. At a length of 525 km (325 mi), the Betsiboka is navigable for at least 140 km (about 80 mi) inland, making it useful for shipping. The port city of Mahajanga, visible to the bottom (eastern) side of the bay in the photograph, is a major transportation center, and home to some industry and educational centers.

The river’s waters are also used to irrigate crops. Agriculture is the primary economic activity in Madagascar, but it has been suffering lately. Only a small percent of the island’s land area is suitable for farming, and traditional slash-and-burn methods are still in use. Although deciduous forests once covered the west coast, logging has led this part of the island has become a savannah. The clearing of the native forests has greatly increased soil erosion. In the past 50 years, annual soil losses have grown in some regions of the island to be among the largest recorded in the world. From the picture, the brick-red sediment in the river delta is apparent (the color of the soil is the result of tropical weathering that has leached the soil of many minerals, leaving mostly reddish iron compounds). However, reforestation programs have been started in recent years, along with the modernization of agricultural methods. The country has a history of conservation and was the first African country to take part in a debt-for-nature trade, where foreign debts are forgiven in exchange for conservation measures.