CRC Press Soil Clays: Linking Geology, Biology, Agriculture, and the Environment

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. About the Author G. Jock Churchman is adjunct senior lecturer at the University of Adelaide (Australia) and adjunct associate professor at the University of South Australia. Jock Churchman’s clay interests began with a PhD in chemistry on halloysite at the University of Otago in his native New Zealand, followed by industrial ceramic research (1970–1971). He held a postdoctoral fellowship in soil science at the University of Wisconsin–Madison (1971–1973) and was employed at the New Zealand Soil Bureau (1973–89), then at CSIRO (1989–2003), the University of Adelaide (2003–2012) and the University of South Australia (2013–2014). He has also held visiting fellowships in soil science for one year at Reading University (UK) and for six months at the University of Western Australia. His research has encompassed halloysite; acid dissolution of montmorillonite; dust transport; clay mineral genesis; clay–organic complexes; the influence of clay mineralogy on soil physical properties; clays in sodic soils; the characteriation of bentonites and their industrial and environmental applications; and the philosophy of soil science. He has published nearly 150 refereed papers and coedited four books, most recently The Soil Underfoot: Infinite Possibilities for a Finite Resource (CRC Press, 2014) and Natural Mineral Nanotubes (CRC Press, 2015). He is a former editor (now emeritus) of Applied Clay Science. He has received awards from the New Zealand Society of Soil Science, Soil Science Australia, the Association Internationale pour l’Étude des Argiles (AIPEA) and the Clay Minerals Society.   Bruce Velde is an emeritus researcher for the Centre Nationale de Recherche Scientifique at the Ecole Normale Supérieure in Paris. He did his PhD at Montana State University (1962) under the direction of John Hower, then he did a postdoctoral study