Digital Soil mapping in Africa for food security.

In Nairobi, Kenya, a group of modern day explorers is providing the data for a first-ever set of digital maps of African soils. Traditional maps, the scientists say, provide information on broad soil types but not on specific soil properties. The new maps provide direct information on soil properties at a level of accuracy once considered all but unachievable. Detailed maps are now available that are helping thousands of subsistence farmers to maximize their production of basic food crops, an effort that many experts believe will also take the pressure off Africa’s forests and marginal lands and help reduce global climate change. When you know what your soils can do and how to take care of them, that’s an all-important first step to maximizing production and once farmers can produce enough to feed their families and produce surpluses, the back-breaking work of cutting down forests to grow crops will no longer be necessary. A group of scientists is producing the maps using technologies known as infrared and x-ray spectroscopy. what it entails is to shine light on a soil or plant sample and measure the amount of light reflected back at different wavelengths or energy levels, much in the same way that a digital camera records color. The spectral signature, or fingerprint, gives information about the sample’s mineral and organic composition. These characteristics determine a soil’s functional capacity its ability to retain and supply water and nutrients and to store carbon. This information can then be used to determine the soil’s potential and make highly accurate recommendations about what farmers need to do to improve the health of their soils and produce better crops. more