Submitted to: Book Chapter
Publication Type: Other
Publication Acceptance Date: 11/17/2008
Publication Date: 2/13/2009
Citation: Laird, D.A., Cervini-Silva, J. 2009. Carbon Stabilization by Clays in the Environment: Process and Characterization Methods. In: Laird, D.A., Cervini-Silva, J., editors. CMS Workshop Lectures, Volume 16. Chantilly, VA: Clay Minerals Society. Interpretive Summary:
Technical Abstract: Organic matter (OM) in soil plays vital roles with respect to global climate change, as the largest terrestrial reservoir of organic carbon, and with respect to soil quality through the stabilization of soil structure and the retention and cycling of plant nutrients. The interactions between clay minerals and OM are central to most of these functions. Clays may catalyze formation of new humic substances, inhibit the degradation of existing humic substances through physical sequestration, and clay-humic associations are at the very heart of aggregation and soil structure stabilization. In this book we seek to explore the state of knowledge related to these topics and the analytical tools used to investigate them. In chapter 1, Hayes et al. describe chemical fractionation techniques and relate the clay bound soil OM to the "humin" fraction. Chen and Tarcjotzly (Chapter 2) discuss the role of humic substances and polysaccarides is formation and stabilization of soil structure. Gonzalez (Chapter 3) considers the potential catalytic role of clays in the formation of new humic materials. Wershaw (Chapter 4) considers the nature of soil OM and clay-humic complexes as revealed by nuclear magnetic resonance (NMR) and other techniques. The last two chapters, Chenu et al. (Chapter 5) and Laird and Thompson (Chapter 6), focus directly on understanding the nature of clay-humic complexes as revealed by electron microscopic techniques. It is hoped that this volume will provide the reader with both advanced understanding of the current state of knowledge and an appreciation for the gaps in that knowledge, which will challenge a future generation of scientists.