The word Sahel is Arabic for edge or shore of the desert, and it refers to a strip of arid land which runs across Africa. Water is precious because rainfall is both infrequent and sparse. The region is faced with severe land degradation, caused by increasing desertification and soil erosion - the direct result of deforestation in recent decades.

The Sahel has few natural resources, and drought is a common feature of life. Over the centuries people have developed survival strategies to cope with the harsh climate and arid land, but in recent decades many of these strategies have been abandoned in the name of development, and people have relied on cash crops, including peanuts, shea nuts, and sesame. During the 1970s and 1980s the people of the Sahel experienced drought and famine on an unprecedented scale; the cash crops failed and tens of thousands of people died.

Unfortunately for the people of Burkina Faso, these dry conditions have been creeping southwards, threatening to turn farmland to desert. Farmers everywhere say that the rainfall is less than it was when they were children, and the rainy season much shorter. Rainfall records support these claims.

Nomadic herders make good use of these difficult conditions, moving their sheep, goats, cows and camels to areas which have received the most rain. The reasons for these worsening conditions are not clear. Some scientists believe that the world's climate has been changing, leading to an expansion of the Sahara desert and the Sahel. But it also seems certain that deforestation has played an important part, as farmers have cleared land for their crops and removed trees for fuelwood. Without trees and plants to protect it, the soil is carried away in the dry season by hot easterly winds, and washed into the rivers during the rains. The bare land reflects the sun's heat, reducing clouds and further reducing the chance of rain.