The Sahel or Sahel Belt (from Arabic ساحل, sāḥil, shore, border or coast of the Sahara) is a semi-arid tropical savanna and steppe ecoregion in Africa, which forms the transition between the Sahara to the north and the slightly less arid savanna belt to the south, known as the Sudan (not to be confused with the country of the same name).
The Sahel runs 2,400 miles (3862 km) from the Atlantic Ocean in the west to the Red Sea in the east, in a belt that varies from several hundred to a thousand kilometers (620 miles) in width, covering an area of 3,053,200 square kilometers (1,178,800 square miles). It is a transitional ecoregion of semi-arid grasslands, savannas, steppes, and thorn shrublands lying between the wooded Sudanian savanna to the south and the Sahara to the north.[1] The countries of the Sahel today include Senegal, Mauritania, Mali, Burkina Faso, Niger, Nigeria, Chad, Sudan, and Eritrea.
The topography of the Sahel is mainly flat, and the region mostly lies between 200 and 400 meters elevation. Several isolated plateaus and mountain ranges rise from the Sahel, but are designated as separate ecoregions because their flora and fauna are distinct from the surrounding lowlands.[2]
Over the history of Africa the region has been home to some of the most advanced kingdoms benefiting from trade across the desert. Collectively these states are known as the Sahelian kingdoms.
Traditionally, most of the people in the Sahel have been semi-nomads, farming and raising livestock in a system of transhumance, which is probably the most sustainable way of utilizing the Sahel. The difference between the dry north with higher levels of soil-nutrients and the wetter south is utilized so that the herds graze on high quality feed in the North during the wet season, and trek several hundred kilometers down to the south, to graze on more abundant, but less nutritious feed during the dry period. Increased permanent settlement and pastoralism in fertile areas has been the source of conflicts with traditional nomadic herders.
There was a major drought in the Sahel in 1914, caused by annual rains far below average, that caused a large-scale famine. The 1960’s saw a large increase in rainfall in the region, making the Northern drier region more accessible. There was a push, supported by governments, for people to move northwards, and as the long drought-period from 1968 through 1974 kicked in, the grazing quickly became unsustainable, and large-scale denuding of the terrain followed. Like the drought in 1914, this led to a large-scale famine, but this time it was somewhat tempered by international visibility and an outpouring of aid. This catastrophe led to the founding of the International Fund for Agricultural Development.