Iron In Soils And Clay Minerals

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.

The geobiochemical cycle of iron; An introduction to physical and chemical principles; Solubility and redox equilibria of iron compounds in soils; Separation and concentration of iron-containing phases; Phase identification by selective dissolution techniques; The assay for iron in soils and clay minerals; Introduction to crystal structures of iron-containing minerals; The application of micro-beam methods to iron minerals in soils; Some properties of soil and synthetic iron oxides; Occurrence and formation of iron oxides in various pedoenvironments; Properties and behavior of iron oxides as determined by mossbauer spectroscopy; Iron compounds as indicators of pedogenic processes: examples from the southern hemisphere; Magnetic properties of iron in soil iron oxides and clay minerals; Structural iron in kaolinites and in associated ancillary minerals; Role of iron in mica weathering; Structural iron in smectites; The characterization of iron complexes with soil organic matter; Chemistry of iron in calcareous systems; Microbiological reactions of iron in soils; The fate of iron during soil formation in humid-temperate environments; Laterites and laterization processes; Effects of seasonal redox processes involving iron on the chemistry of periodically reduced soils; Long-term chemical, mineralogical, and morphological effects of iron-redox processes in periodically flooded soils; Redox processes of iron and sulfur involved in the formation of acid sulfate soils.

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.

As the human population grows from seven billion toward an inevitable nine or 10 billion, the demands on the limited supply of soils will grow and intensify. Soils are essential for the sustenance of almost all plants and animals, including humans, but soils are virtually infinitely variable. Clays are the most reactive and interactive inorganic compounds in soils. Clays in soils often differ from pure clay minerals of geological origin. They provide a template for most of the reactive organic matter in soils. They directly affect plant nutrients, soil temperature and pH, aggregate sizes and strength, porosity and water-holding capacities. This book aims to help improve predictions of important properties of soils through a modern understanding of their highly reactive clay minerals as they are formed and occur in soils worldwide. It examines how clays occur in soils and the role of soil clays in disparate applications including plant nutrition, soil structure, and water-holding capacity, soil quality, soil shrinkage and swelling, carbon sequestration, pollution control and remediation, medicine, forensic investigation, and deciphering human and environmental histories. Features: Provides information on the conditions that lead to the formation of clay minerals in soils Distinguishes soil clays and types of clay minerals Describes clay mineral structures and their origins Describes occurrences and associations of clays in soil Details roles of clays in applications of soils Heavily illustrated with photos, diagrams, and electron micrographs Includes user-friendly description of a new method of identification To know soil clays is to enable their use toward achieving improvements in the management of soils for enhancing their performance in one or more of their three main functions of enabling plant growth, regulating water flow to plants, and buffering environmental changes. This book provides an easily-read and extensively-illustrated description of the nature, formation, identification, occurrence and associations, measurement, reactivities, and applications of clays in soils.

This book represents a rather complicated history of encounters, changes in research interest and some very interesting results. Initially it is the very fruitful interaction of Ecology and Geology. The point of view of ecologists is extremely refreshing for hard science people. Interaction and inter-relationships are the focus of Ecology whereas the traditional sciences, such as Geology, have tried to isolate the natural phenomena so that thye could be studied in a more rigorous manner. The traditional sciences were of course natural science – based since the world to be observed was at the door step of everyone, mountains, weather patterns, plants and so forth. Chemistry and Physics were de ned after Mathematics in order to establish more precise and viable principles of the behavior of the materials that formed the world around mankind. It became quite clear that the observation of the natural world was too complicated to consider all of the possible variables which could affect an observed process or situation. The systems were simpli ed and taken into the laboratory in order to better master the phenomena observed. Physics c- cerned itself with non-reacting materials, subjected to essentially mechanical forces.

The first edition of the Handbook of Clay Science published in 2006 assembled the scattered literature on the varied and diverse aspects that make up the discipline of clay science. The topics covered range from the fundamental structures (including textures) and properties of clays and clay minerals, through their environmental, health and industrial applications, to their analysis and characterization by modern instrumental techniques. Also included are the clay-microbe interaction, layered double hydroxides, zeolites, cement hydrates, and genesis of clay minerals as well as the history and teaching of clay science. The 2e adds new information from the intervening 6 years and adds some important subjects to make this the most comprehensive and wide-ranging coverage of clay science in one source in the English language. Provides up-to-date, comprehensive information in a single source Covers applications of clays, as well as the instrumental analytical techniques Provides a truly multidisciplinary approach to clay science

Of huge relevance in a number of fields, this is a survey of the different processes of soil clay mineral formation and the consequences of these processes concerning the soil ecosystem, especially plant and mineral. Two independent systems form soil materials. The first is the interaction of rocks and water, unstable minerals adjusting to surface conditions. The second is the interaction of the biosphere with clays in the upper parts of alteration profiles.