Water and N are two factors that have a major influence on crop production. Water is provided by rainfall, and where rainfall is insufficient, supplemental irrigation is used. Similarly, N needs can be provided by using legumes and other N2-fixing systems, or supplemented with N fertilizer and manures. Since crop production is at the beginning of most human food chains and is a essential human activity, water and N influence human health, welfare, and economics in critical ways. Therefore, it is important to understand the interaction of water and N in cropping systems, responses to these vital inputs, and ways of managing water and N most efficiently.
Cropping Strategies for Efficient Use of Water and Nitrogen deals with water and N management from several perspectives, including crop species, crop sequences, cultural practices, inputs, and environmental quality.
We greatly appreciate the contributions of W. L. Hargrove and B. G. Ellis, co-editors, and their editorial committee. We are also grateful to W. L. Hargrove, A. L. Black, and J. V. Mannering for organizing the symposium in which the papers that later were developed into chapters for this book were first presented. We wish to thank the authors for sharing their knowledge, experience, and insights on this subject.
This book is a valuable contribution to scientific, technological, and practical understanding of an important topic. We think you will find it informative and stimulating.
D. A. Holt, president
American Society of Agronomy
C. J. Nelson, president
Crop Science Society of America
D. R. Keeney, president
Soil Science Society of America
The very existence of the human race on this earth depends upon good management and wise stewardship of natural resources to produce food and fiber. The United States has been at the forefront of the science of increasing food and fiber production and as a result has achieved an abundance of food that is cheap, and a high standard of living. But, environmental problems, increasing public concern about degradation of ground waters, and an economic dependency upon fossil fuels have also resulted. Concern for efficient use of N and water, while still protecting our environment, led to the development of a symposium at the 1987 Annual Meetings of the American Society of Agronomy at Atlanta, GA. The symposium was co-sponsored by Div. S-4, S-6, S-8, C-3, and A-6. Twelve papers were presented which address many factors that affect the efficiency of water and N use.
Cropping Stretegies for Efficient Use of Water and Nitrogen is the written publication from the papers that were presented at the symposium. Papers discuss the use of cropping systems to gain N2 fixation and efficiency of utilization of this fixed N. Cropping systems, including rotations, multiple cropping, intercropping and specific cropping systems for low input agriculture as well as using specific cropping systems for reduced leaching of salts are topics included in the papers. The keen interest in groundwater quality and in reducing crop production costs while maintaining acceptable yield make the publication a timely contribution.
We, as members of the society, are indebted to the authors whose work has collected thoughts, concepts, and data that relate to this important topic. It is our hope that this will stimulate thinking about research that is essential for more efficient use of two of our most important resources, N and water, in our agricultural production systems. We wish to thank the reviewers who contributed suggestions for improvement of the manuscripts and for the many who stimulated discussion at the symposium. We also appreciate the excellent work of the ASA Headquarters staff in the publication process.
W.L. Hargrove, co-chair
B.G. Ellis, co-chair
R. W. Andrews, Editorial Research Assistant, Rodale Research Center, Kutztown, Pennsylvania
A. L. Black, USDA-ARS, Northern Great Plains Research Lab., Mandan, North Dakota
R. L. Blevins, Professor of Agronomy, Department of Agronomy, University of Kentucky, Lexington, Kentucky
S. J. Corak, Graduate Research Assistant, Department of Agronomy, University of Kentucky, Lexington, Kentucky
J. W. Doran, Soil Scientist, USDA-ARS, University of Nebraska, Lincoln, Nebraska
W. W. Frye, Professor of Agronomy, Department of Agronomy, University of Kentucky, Lexington, Kentucky
G. J. Gascho, Professor, Department of Agronomy, Coastal Plains Experiment Station, University of Georgia, Tifton, Georgia
A. D. Halvorson, Soil Scientist, USDA-ARS, Akron, Colorado
W. L. Hargrove, Associate Professor, Department of Agronomy, Georgia Agricultural Experiment Station, University of Georgia, Griffin, Georgia
O. B. Hesterman, Assistant Professor, Crop and Soil Sciences Department, Michigan State University, East Lansing, Michigan
J. E. Hook, Associate Professor, Agronomy Department, Coastal Plain Experiment Station, University of Georgia, Tifton, Georgia
R. R. Janke, Agronomy Coordinator, Rodale Research Center, Kutztown, Pennsylvania
D. L. Karlen, Soil Scientist, USDA-ARS, Department of Agronomy, Iowa State University, Ames, Iowa
G. W. Langdale, USDA-ARS, Southern Piedmont Conservation Research Center, Watkinsville, Georgia
J. V. Mannering, Professor, Department of Agronomy, Purdue University, West Lafayette, Indiana
D. B. Mengel, Professor of Agronomy, Department of Agronomy, Purdue University, West Lafayette, Indiana
R. I. Papendick, Soil Scientist, USDA-ARS, Land Management and Water Conservation, Washington State University, Pullman, Washington
S. E. Peters, Research Agronomist, Rodale Research Center, Kutztown, Pennsylvania
Francis J. Pierce, Assistant Professor, Department of Crop and Soil Sciences, Michigan State University, East Lansing, Michigan
J. F. Power, Research Leader, USDA-ARS, University of Nebraska, Lincoln, Nebraska
J. K. Radke, Research Soil Scientist, USDA-ARS, Rodale Research Center, Kutztown, Pennsylvania
Charles W. Rice, Assistant Professor, Department of Agronomy, Kansas State University, Manhattan, Kansas
E. J. Sadler, Soil Scientist, USDA-ARS, Coastal Plains Soil and Water Conservation Research Center, Florence, South Carolina
James S. Schepers, Soil Scientist, USDA-ARS, University of Nebraska, Lincoln, Nebraska
M. S. Smith, Professor of Agronomy, Department of Agronomy, University of Kentucky, Lexington, Kentucky
R. E. Sojka, Soil Scientist, USDA-ARS, Snake River Soil and Water Management Research Unit, Kimberly, Idaho
P. W. Unger, Soil Scientist, USDA-ARS, Conservation and Production Research Lab., Bushland, Texas
J. J. Varco, Assistant Professor of Agronomy, Department of Agronomy, Mississippi State University, Mississippi State
M. G. Wagger, Assistant Professor, Department of Crop Science, North Carolina State University, Raleigh, North Carolina