The presence - or absence - of soil organic matter (SOM) has important implications for agricultural productivity. It could also have significant implications for global climate due to its role as a source/sink of carbon. Therefore, it is important to understand the issues related to the accumulation or loss of SOM, to use what we have learned from experiments to make sound decisions about soil and crop management, and to test models and future concepts concerning SOM management. A database is included with the book, presenting tabular data for 34 sites in North America. Soil Organic Matter in Temperate Agroecosystems discusses all of these issues and more, answering such questions as:

E.A. Paul, Ph.D., Professor, Department of Crop and Soil Sciences, Michigan State University, has served as Chairperson of Crop and Soil Sciences at Michigan State University and as Chair of the Department of Plant and Soil Biology, University of California - Berkeley. Before that he was Professor of Soil Science at the University of Saskatchewan, Saskatoon, Canada. His major fields of interest shown in the extensive papers published have included microbial ecology, soil organic matter dynamics, nutrient cycling, and plant microbial interactions. National and international committees and professional society appointments have helped both his science and his profession. He has taught extensively at the undergraduate and graduate level and advised many successful students both in Canada and the U.S. Books edited include volumes 3, 4, and 5 of Soil Biochemistry published by Marcel Dekker. The textbook, Soil Microbiology and Biochemistry, co-edited with F.E. Clark and published by Academic Press has extensive readership and is being translated into three languages other than English. He is a fellow of the Canadian Society Soil Science, American Society of Agronomy, Soil Science Society of America, and the American Association for the Advancement of Science and a recipient of the Soil Science Society of America Research Award.

Keith Paustian, Ph.D., is a Senior Research Scientist at the Natural Resource Ecology Laboratory (NREL), Colorado State University. Prior to his appointment at NREL in 1993, he was a Research Assistant Professor at the W.K. Kellogg Biological Station, Michigan State University (1989-1993) and Research Scientist at the Department of Ecology and Environmental Research, Swedish University of Agricultural Sciences, Uppsala, Sweden (1987-1989).

Edward T. Elliott, Ph.D., is the Associate Director of the Natural Resource Ecology Laboratory and holds a joint appointment as Professor in the Soil and Crop Sciences Department at Colorado State University. He is the Director of the University Office of Ecosystem Research and Management. His B.Sc. and M.Sc. in Soil Science were obtained at Colorado State University and his Ph.D. in Ecology is from the University of Georgia, where he studied freshwater ecology.

C. Vernon Cole, Ph.D., is a Senior Research Scientist with the Natural Resource Ecology Laboratory, Colorado State University. He was a Research Soil Scientist with the Agricultural Research Service, USDA from 1950 until his retirement in 1993. He contributed to significant advances in the knowledge of phosphorus chemistry in the first years of his career. A practical soil test developed from this research has been used worldwide and is the basis for identifying phosphorus deficient soils in much of the neutral and slightly weathered soils of the world.

PART I: THE ROLE OF SOIL ORGANIC MATTER IN AGRICULTURAL SYSTEMS AND GLOBAL CHANGE, 1. Impacts of Agriculture on Atmospheric Carbon Dioxide, 2. Management Controls on Soil Carbon, 3. Characterization of Soil Organic Carbon Relative to Its Stability and Turnover, 4. Crop Residue Input to Soil Organic Matter on Sanborn Field, 5. Biogeochemistry of Managed Grasslands in Central North America, PART II: SITE MANAGEMENT EFFECTS ON PRODUCTIVITY AND SOIL ORGANIC MATTER IN THE CORN BELT, 6. Nitrogen Fertilizer and Legume-Cereal Rotation Effects on Soil Productivity and Organic Matter Dynamics in Wisconsin, 7. Long-Term N Management Effects on Com Yield and Soil C of an Aquic Haplustoll in Minnesota, 8. Long-Term Effects of Fertilizer and Manure on Com Yield, Soil Carbon, and Other Soil Chemical Properties in Michigan, 9. Long-Term Tillage and Periodic Plowing of a No-Tilled Soil in Michigan: Impacts, Yield, and Soil Organic Matter, 10. Soil Organic Matter in Sugar Beet and Dry Bean Cropping Systems in Michigan, 11. Soil Organic Carbon Changes Through Time at the University of Illinois Morrow Plots, 12. Continuous Application of No-Tillage to Ohio Soils: Changes in Crop Yields and Organic Matter-Related Soil Properties, 13. Management Impacts on SOM and Related Soil Properties in a Long-Term Farming Systems Trial in Pennsylvania: 1981-1991, 14. Crop Rotation, Manure, and Agricultural Chemical Effects on Dryland Crop Yield and SOM over 16 Years in Eastern Nebraska, 15. Sanborn Field: Effect of 100 Years of Cropping on Soil Parameters Influencing Productivity, 16. Soil Organic Matter under Long-Term No-Tillage and Conventional Tillage Com Production in Kentucky, 17. Long-Term Patterns of Plant Production and Soil Carbon Dynamics in a Georgia Piedmont Agroecosystem, 18. Soil Carbon Level Dependence upon Crop Culture Variables in a Thermic-Udic Region, 19. Changes in Ecosystem Carbon 46 Years after Establishing Red Pine (Pinus resinosa Ait.) on Abandoned Agricultural Land in the Great Lakes Region, PART III: SITE MANAGEMENT EFFECTS ON PRODUCTIVITY AND SOIL ORGANIC MATTER CHARACTERISTICS IN THE GREAT PLAINS, 20. Crop Yield and Soil Organic Matter Trends over 60 Years in a Typic Cryoboralf at Breton, Alberta, 21. Soil Organic Matter Dynamics in Long-Term Experiments in Southern Alberta, 22. Crop Production and Soil Organic Matter in Long-Term Crop Rotations in the Sub-Humid Northern Great Plains of Canada, 23. Crop Production and Soil Organic Matter in Long-Term Crop Rotations in the Semi-Arid Northern Great Plains of Canada, 24. A Conservation Tillage-Cropping Systems Study in the Northern Great Plains of the United States, 25. Soil Organic Matter Changes over Two Decades of Winter Wheat-Fallow Cropping in Western Nebraska, 26. Soil Carbon and Nitrogen Change in Long-Term Agricultural Experiments at Pendleton, Oregon, 27. Long-Term Tillage and Crop Residue Management Study at Akron, Colorado, 28. Management of Dryland Agroecosystems in the Central Great Plains of Colorado, 29. Management Effects on Soil Organic Carbon and Nitrogen in the East-Central Great Plains of Kansas, 30. Management of Dry-Farmed Southern Great Plains Soils for Sustained Productivity, PART IV: SOIL, CROP, AND MANAGEMENT OF LONG-TERM EXPERIMENTS IN NORTH AMERICA*, Arlington, WI: N Effects on Continuous Com, Lancaster, WI: Crop Rotation and Nitrogen Fertilizer Effects, Lamberton, MN: Nitrogen Rate and Application Method Effects on Continuous Com, East Lansing, MI: Manure-Fertilizer Effects on Com, Grain, and Silage, East Lansing, MI: No-Till Sequences and Cover Crops, Saginaw Valley, MI: Com-Sugarbeet-Navy Bean-Alfalfa Rotations, Champaign-Urbana, IL: The Morrow Plots, Established 1876, Wooster, OH: Tillage-Crop Rotations on an Upland Glacial Till, Hoytville, OH: Tillage-Crop Rotations on a Poorly Drained Glacial Till, South Charleston, OH: Tillage Effects on Continuous Com Crop Rotations, Kutztown, PA: The Rodale Reversion Experiment, Mead, NE: Crop Rotations, Manure, Fertilizer, and Herbicide Interactions, Sanborn Field Missouri: Site Description, Design, Management, Lexington, KY: No Till and Nitrogen Fertilizer Interactions, Athens, GA: The Horseshoe Bend Cropping Systems Experiment, Watkinsville, GA: Crop Culture Variables and Rainfall Infiltration, Breton, Alberta: Crop Rotations on a Northern Wooded Soil, Lethbridge, Alberta: Hist…