This book, based on research carried out at the Academia Sinica over the past 30 years, explains the basic difference between the variable charge soils of tropical and subtropical regions, and the constant charge soils of temperate regions. It will focus on the chemical properties of the variable charge soils--properties which have important bearing on soil management practices, including maximizing soil productivity and combating soil pollution.
Morphology: Morphological characteristics of alfisols and ultisols; The morphological characteristics of andisols; Morphological properties of oxisols; The morphological properties of spodosols; Mineralogical characteristics of alfisols and ultisols; Mineralogical characteristics of andisols; Mineralogy of oxisols and oxic materials; The mineralogy of spodosols; Chemistry: Adsorption and charging phenomena in variable charge soils; Chemical properties of variable charge soils; Soils with variable charge: agronomic and fertility aspects; Organic matter and its interactions with inorganic soil constituents; Physics and mechanics: Physical and mechanical characteristics of alfisols and ultisols, with particular reference to soils in the tropics; Physical and mechanical characteristics of andisols; Physical and mechanical properties of oxisols; The physical properties of spodosols; Biology: Ecology of soil micro and macro organisms; Dynamics and stability of organic matter; Genesis and classification: Genesis and classification of low activity clay alfisols and ultisol; Genesis and classification of andepts and spodosols; Classification and genesis of oxisols.
Probably more than any other element, iron markedly influences the chemical and physical properties of soils and sediments in the earth. Considering its transition metal status, with potential variation in electronic configuration, ionic radius, and magnetic moment, combined with its abundance and relatively large mass, little wonder that one sees its unique influence on every hand. Pre sentations at the NATO Advanced Study Institute (NATO AS!) on Iron in Soils and Clay Minerals reviewed and discussed the occurrence, behavior, and properties of Fe-bearing minerals found in soils and in the clay mineral groups kaolinite, smectite, and mica. Also discussed at the NATO AS! were the basic chemical properties of Fe, methods for separating and identifying Fe in minerals, and the role of Fe minerals in weathering and other soil-forming processes. The present publication is the reviewed and edited proceedings of that Advanced Study Institute. The sequence of chapters follows the general pattern beginning with introductory chapters which overview the general occurrence of Fe in the earth and its chemistry, both generally and in mineral environments, followed by identification and characterization methods for Fe and Fe phases in minerals. The properties and behavior of Fe oxides, Fe-bearing clay minerals, and other Fe minerals in soils are then described, and the text ends with a summary of the role of Fe in soil-forming processes. A Table of Contents and subject index are provided to assist the reader in finding specific topics within the text.
