Environmental Chemistry and Engineering

Biography

Biography: Theophilus Clavell Davies

Abstract

The significance of a complete, high quality African geochemical database (AGD) for addressing the range of Earth and environmental science issues (e.g., mineral exploration, resource evaluation, agriculture, land use planning, processes of crustal evolution, modeling of environmental systems) cannot be over-emphasized; because, for such applications to be made in a robust fashion, we need to understand how the region’s unique and complex geochemical landscape was carved out in the first place. The distinctive nature of Earth processes such as intense tropical weathering, leaching, erosion, podsolization and gleying, as well as later imprints of urbanization and industrialization, have engendered the mobilization and clear redistribution of all but the most refractory elements. As a consequence, it is not uncommon to find large tracts of the continent’s surface environment containing anomalous trace element contents or deficiencies in essential micro-nutrient elements. Through water and food crops, extremes in trace element variation in soils are transmitted into the food chain, with often undesirable consequences for human and animal health. It is thus considered that one of the most important applications of an AGD would be in understanding the hydrological, chemical and biological processes that determine the behaviour of nutritional and toxic elements in the surface environment, in relation to how they may affect the health of man and animals (Medical Geology). This is so, because most of Africa’s population still live close to the land, and depend on it for their daily sustenance. Important scientific problems that would confront the construction of an AGD include defining and understanding regional background and the evolution of appropriate sampling and analytical protocols that would take into account the regions’ unique and complex element distribution patterns in the surface environment. These problems are apparently intractable, but are not unsolvable. Longstanding operational and logistical problems that have impeded previous (largely uncoordinated) efforts at an AGD compilation include the limited availability of state-of-the art analytical instrumentation and requisite laboratory infrastructure. An even more important limitation is the dearth of a sufficient number of highly skilled analytical geochemists and other technical personnel located at appropriate regional centers, which are able to install, operate, trouble-shoot and maintain modern analytical equipment. These problems are compounded by the lack, up to now, of adequate international funding to undertake such a high precision and systematic mapping exercise. In this presentation, recommendations are put forward for carrying out a successful and complete compilation of a high quality AGD that would be invaluable for studies in Medical Geology, as well as in an array of other multipurpose, multi-national environmental applications; and proposed measures given for counteracting potential limitations in its development.