An adequate supply of micronutrients is essential for balanced plant growth. In Africa, micronutrient constraints are known to restrict crop productivity and impair human welfare and health. We analyzed a total of 816 topsoil and 796 subsoil samples from Sub-Saharan Africa, to provide baseline information on their readily available Al, B, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, V, and Zn concentrations. This work builds on previous global micronutrient surveys. The studied soils were low in hot water-extractable B, acid ammonium acetate-EDTA-extractable micronutrients, and potentially harmful metals. In comparison with tentative critical level values, B, Cu, Zn, Mo, and Fe in a considerable number of samples seemed to be at a low level for crop production. Apart from Al, Mo, V, Pb, and Cr, readily available element concentrations were higher in topsoil than subsoil. Concentrations of harmful metals (Cd, Ni, Pb) and of Mn and Mo were enriched in cultivated soils in comparison with semi-natural sites. Among the 11 Reference Soil Groups represented in the study, Arenosols were discernible as poor in Cr, Cu, and Fe. Other significant differences in microelement concentrations between soil groups were found only for Ni and V.
Tag: micronutrient
Biodiversity and nutrition
Malnutrition remains one of the greatest global health challenges we face and women and children are its most visible and vulnerable victims. Agricultural production is theoretically able to feed the world’s population in terms of calories (FAOSTAT, 2014), yet it is estimated that half the world’s population still suffers from one or more forms of malnutrition. In all its forms, malnutrition is closely linked to disease – as both a cause and effect – and it is the single largest contributor to the global burden of disease (WHO 2012a).Countries are increasingly facing complex multiple burdens of malnutrition, with undernutrition and micronutrient deficiencies coexisting with overweight and obesity in many parts of the world, often even within the same population or family (Shrimpton 2013). Based on data released in 2014, 161 million children under the age of five are estimated to be stunted, almost 1.5 billion people are estimated to be overweight, over 600 million to be obese (Ng et al. 2014) and two billion are estimated to be deficient in one or more micronutrients, a phenomenon referred to by some as “hidden hunger”. These conditions all have severe consequences for survival, for morbidity, and for the ability of individuals, the economy and society to thrive (IFPRI 2014)