Soil micronutrients are essential to plants, animals and humans. Lack of these elements can retard growth and thus cause severe problems. The soil micronutrients in Africa are now being mapped extensively for the first time in order to improve local food security. The study is done within the research and development programme FoodAfrica, coordinated by MTT Agrifood Research Finland.

There is very little and scattered information on soil micronutrients and their deficiencies in African agricultural lands, even though notable deficiencies are likely to be found. Deficiencies of some elements, like iron, are known to cause severe problems to humans, like dwarfing of children, whereas lack of zinc and some other elements may retard plant growth, cause poor yields and reduce the effect of other nutrients.

–    It is important to carry out surveys on soil micronutrients so that we can improve their concentrations through fertilizers or catch crops, for example. We can also improve the well-being of humans and animals through a more diversified diet, says Riikka Keskinen, Senior Research Scientist at MTT Agrifood Research Finland.

Mapping of micronutrients supports local food production

MTT Agrifood Research Finland and World Agroforestry Centre ICRAF are now mapping the soil micronutrients in Sub-Saharan Africa within the FoodAfrica programme. The goal is to get a common picture of the micronutrient status and distribution in the region.

–    Once we get a common view on the micronutrient status, we may continue to work with the areas where deficiencies are most likely to be found. In those areas we can find solutions to the problems by doing more thorough soil testing and field experiments. We can also demonstrate different kinds of solutions to the local farmers and authorities, says Professor Martti Esala from MTT Agrifood Research Finland.

The soil micronutrient mapping is linked to the African Soil Information Service (AfSIS), an ICRAF-supported project that is developing continent-wide digital soil maps for sub-Saharan Africa using new types of soil analysis and statistical methods.

–    We are working on new, low-cost and fast methods of soil and plant micronutrient analysis that use only light instead of chemicals, which will make it easier to produce this kind of information even for smallholders in Africa, says Dr. Keith Shepherd from ICRAF.