Metal oxides

Oxide minerals (include oxides, hydroxides, oxyhydroxides and hydrated oxides) are primary and secondary minerals of Si, Fe, Mn, Al and Ti. Secondary oxides, particularly of Fe, Al and Mn, are perhaps the most reactive and important components in many soils due to their large specific surface area and strong sorption capacity for many essential and potentially toxic elements. Iron and Mn oxides also play key roles in many redox reactions and have a major influence on the transformation and availability of organic and inorganic contaminants in soils. This chapter provides an overview of the oxide minerals in soils, with an emphasis on their structure and composition, environmental conditions for their formation and their properties.