Population swells, climate change, soil degradation, erosion, poaching, global food prices and even the benefits of affluence are exerting incredible pressure on African land. Large groups of people are on the move, desperate for usable land. One recent study shows that more than 40 million Africans are trying to survive off land whose agricultural potential is declining, fueling conflicts across the continent, from Nigeria in the west to Kenya in the east. Large groups of people are on the move, desperate for usable land. Data from NASA satellites reveals an overwhelming degradation of agricultural land throughout Africa.At the same time, high birthrates and lengthening life spans mean that by the end of this century, there could be as many as four billion people on the continent, about 10 times the population 40 years ago.'