Agricultural experts in Africa say the continent faces a crisis of depleted soil and they're hoping that a detailed, high-tech map of soil quality will help them solve the problem. This morning at an event in Nairobi, Kenya, the International Center for Tropical Agriculture announced that it will lead the $18 million effort. Most of the money will come from the Bill and Melinda Gates Foundation.
That price tag sounds almost too good to be true for a map of soil conditions on every hectare of land in sub-Saharan Africa. But Don Doering, project coordinator at the Gates Foundation, says new technology makes it possible. Researchers will first analyze samples of soil from 60 "sentinel sites" across the continent. Each such site—represented by red dots on the map to the left—covers 100 square kilometers. Then, with the help of computer models, scientists will extrapolate to the rest of the continent, predicting soil conditions based on such factors as elevation, how much the land is sloping, and whether it's covered with vegetation.