Drylands represent 40% of the Earth's surface, produce 44% of the world’s food and are home to 80% of the world’s poor. Eighty per cent of Kenya comprises arid or semi-arid lands. Rainfall occurs in just one or two short, intense seasons. Because the land is so dry, when rain does fall, up to 85% of the water is simply lost as run-off. The rain also washes away fertile topsoil and seeds, negatively affecting agricultural production.