NATIONAL ACADEMY PRESS
2101 Constitution Avenue Washington, D.C. 20418
NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competencies and with regard for appropriate balance.
This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.
This report has been prepared with funds provided by the U.S. Department of Agriculture, Soil Conservation Service, under agreement number 68-3A75-9-56; the U.S. Environmental Protection Agency, Office of Policy, Planning, and Evaluation under agreement number C X 818573-01-1; and The Joyce Foundation. Dissemination was supported in part by Pioneer Hi-Bred International, Inc., The Joyce Foundation, The W. K. Kellogg Foundation, the U.S. Department of Agriculture, Soil Conservation Service, and the Environmental Protection Agency, Office of Policy, Planning and Evaluation.
Library of Congress Cataloging-in-Publication Data
Soil and water quality: an agenda for agriculture/Committee on Long-Range Soil and Water Conservation, Board on Agriculture, National Research Council.
Includes bibliographical references and index.
1. Soil management—United States. 2. Soils—United States—Quality. 3. Water quality management—United States. 4. Sediment control—United States. 5. Agricultural ecology—United States. I. National Research Council (U.S.). Committee on Long-Range Soil and Water Conservation.
© 1993 by the National Academy of Sciences. All rights reserved.
Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the organizations or agencies that provided support for this project.
Printed in the United States of America
Committee on Long-Range Soil and Water Conservation
SANDRA S. BATIE, Chair,
Michigan State University*
J. WENDELL GILLIAM,
North Carolina State University
PETER M. GROFFMAN,
Institute of Ecosystem Studies, Millbrook, New York
GEORGE R. HALLBERG,
Iowa Department of Natural Resources
NEIL D. HAMILTON,
Drake University Law School
WILLIAM E. LARSON,
University of Minnesota (Retired)
LINDA K. LEE,
University of Connecticut
PETER J. NOWAK,
University of Wisconsin
KENNETH G. RENARD,
Agricultural Research Service, U.S. Department of Agriculture, Tucson, Arizona
RICHARD E. ROMINGER,
A. H. Rominger and Sons, Winters, California+
B. A. STEWART,
Agricultural Research Service, U.S. Department of Agriculture
KENNETH K. TANJI,
University of California
JAN VAN SCHILFGAARDE,
Agricultural Research Service, U.S. Department of Agriculture
R. J. WAGENET,
DOUGLAS L. YOUNG,
Washington State University
CRAIG COX, Project Director
JOSEPH GAGNIER, Project Associate
JANET OVERTON, Editor
CRISTELLYN BANKS, Senior Secretary and Project Assistant
Board on Agriculture
THEODORE L. HULLAR, Chairman,
University of California, Davis
PHILIP H. ABELSON,
American Association for the Advancement of Science, Washington, D.C.
JOHN M. ANTLE,
Montana State University
DALE E. BAUMAN,
WILLIAM B. DELAUDER,
Delaware State University
SUSAN K. HARLANDER,
Land O'Lakes, Inc., Minneapolis, Minnesota
PAUL W. JOHNSON,
Natural Resources Consultant, Decorah, Iowa
T. KENT KIRK,
U.S. Department of Agriculture, Forest Service, Madison, Wisconsin
JAMES R. MOSELEY,
Jim Moseley Farms, Inc., Clarks Hill, Indiana, and Purdue University
DONALD R. NIELSEN,
University of California, Davis
NORMAN R. SCOTT,
GEORGE E. SEIDEL, JR.,
Colorado State University
PATRICIA B. SWAN,
Iowa State University
JOHN R. WELSER,
The Upjohn Company, Kalamazoo, Michigan
FREDERIC WINTHROP, JR., The Trustees of Reservations,
SUSAN OFFUTT, Executive Director
JAMES E. TAVARES, Associate Executive Director
CARLA CARLSON, Director of Communications
JANET OVERTON, Editor
The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences.
The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Robert M. White is president of the National Academy of Engineering.
The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.
The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. Robert M. White are chairman and vice-chairman, respectively, of the National Research Council.
The list of environmental problems on the agricultural agenda has grown in the past 15 years. The long-standing concerns about soil erosion and sedimentation have been supplemented with new concerns about soil compaction, salinization, and loss of soil organic matter. The transfer of nitrates, phosphorus, pesticides, and salts from farming systems to surface water and groundwater has also become more important.
Efforts to address the larger complex of environmental problems has been hampered by concerns about trade-offs. For example, best-management practices designed to reduce soil loss are now scrutinized for their role in increasing the leaching of nitrates and pesticides to groundwater. Other trade-offs arise between efforts to improve agriculture's environmental performance and efforts to reduce costs of production and maintain U.S. agriculture's share of world markets.
In 1989 the Board on Agriculture of the National Research Council was asked to convene a committee to assess the science, technical tools, and policies needed to protect soil and water quality while providing for the production of food and fiber from U.S. croplands. More specifically, the committee was asked to
investigate the threats to soil resources and recommend criteria to guide soil management;
analyze fate and transport of agricultural chemicals to identify changes in farming systems required to improve water quality;
identify remedial approaches that minimize trade-offs between
improving soil or water quality, surface water or groundwater quality, or between different pollutants; and
recommend policy and program options to improve long-term conservation of soil and water quality.
The committee focused primarily on water quality, rather than water quantity, problems and on croplands rather than on forestlands or rangelands. The committee presents its work in two parts. Part One contains Chapters 1 through 4 and presents the committee's synthesis of the technical, economic and policy issues relating to soil and water quality. In Part Two, Chapters 5 through 12 describe in greater detail the scientific and technical knowledge on which the chapters in Part One are based.
During its deliberative process, the committee first analyzed the physical, chemical, and biological processes that determine farming systems' impact on soil and water quality. The committee analyzed the effects of farming practices on soil, the role of soil in mediating the effect of farming systems on water quality, as well as the processes leading to the loss of nitrogen, phosphorus, pesticides, sediment, salts, and trace elements from farming systems. The committee studied the special problems posed by managing animal wastes and examined the important influence of the landscape in shaping the effects of farming systems on soil and water quality. The results of these analyses are presented in Chapters 5 through 12 of this report. The Appendix describes the methods used by the committee to estimate national, regional, and state nutrient budgets.
Chapter 1 reviews the status of soil and water quality and discusses how and why emphasis has changed over the years from simply soil erosion and sedimentation to include soil degradation and water pollution. The presence of nutrients, pesticides, salts, and trace elements in crops, soil, and drinking water has created new problems that require new solutions. The search for solutions includes recognizing the importance of state and local policies as well as the needs and characteristics of the agricultural sector in efforts to improve soil and water quality.
Based on the understanding gained by analyzing the processes that govern the interaction of farming systems and the environment, the committee identified promising opportunities for managing those processes in ways that protect soil and water quality and are profitable for the producer. The committee's analysis identified four major objectives for the management of soil and water resources:
conserve and enhance soil quality as a fundamental first step to environmental improvement;
increase nutrient, pesticide, and irrigation use efficiencies in farming systems;
increase the resistance of farming systems to erosion and runoff; and
make greater use of field and landscape buffer zones.
These objectives and the technologies available to implement them in agricultural production are presented in Chapter 2.
The task then became to develop strategies to implement those objectives and to identify the changes in concepts, technologies, and policies that might be needed. The farming system concept was central to the development of this report, and the need for a farming system approach at the farm enterprise, regional, and national levels underlies all of the recommendations that the committee developed. The advantages of using a farming systems approach to direct and target soil and water quality programs are presented in Chapter 3.
Ultimately, to achieve long-term improvements in soil and water quality, the behaviors of some producers must be changed. A constant challenge in preparing this report was the attempt to link the social and economic factors that determine producer behavior with the physical, chemical, and biological factors that determine the effects of that behavior on soil and water quality. The committee used the understanding gained from studying these links to recommend a combination of policy and program reforms that will be needed to achieve long-term improvements in soil and water quality. The policy and program reforms recommended by the committee are discussed in Chapter 4.
The debate over national policy to protect soil and water quality has intensified during the course of the committee's deliberation. The 1990 Food, Agriculture, Conservation and Trade Act and the 1990 Coastal Zone Act Reauthorization Amendments created new programs and new authorities that can be used to implement many of the committee's recommendations. Reauthorization of the Clean Water Act and the prospect of a new farm bill in 1995 provide more opportunities to move ahead with an agenda to protect soil and water quality.
A great deal of progress could be made—even in the absence of new legislation—by integrating the multitude of federal, state, and local programs that are already addressing pieces of the soil and water quality problem. The opportunities to make current programs more effective are great and, in many cases, the authorities needed are already provided by legislation. It is the committee's hope that this report will help provide a framework to facilitate the integration of existing and new programs.
SANDRA S. BATIE, Chair
Committee on Long-Range Soil and Water Conservation Policy
A report of this magnitude represents the combined efforts of many individuals from a variety of backgrounds. The committee thanks all those who contributed their ideas and experiences in technical and policy areas. During the course of its deliberations, the committee sought advice and special assistance. Among those who gave generously of their time were Raymond R. Allmaras, University of Minnesota; Ramon Aragues, Agricultural Research Service, Zaragosa, Spain; Peter E. Avers, U.S. Department of Agriculture, Forest Service at Washington, D.C.; Russell R. Bruce, U.S. Department of Agriculture, Agricultural Research Service at Watkinsville, Georgia; H. H. Cheng, University of Minnesota; C. V. Cole, U.S. Department of Agriculture, Agricultural Research Service at Colorado State University; Cornelia Butler Flora, Virginia Polytechnic Institute and State University; George R. Foster, U.S. Department of Agriculture, Agricultural Research Service at Oxford, Mississippi; Robert Grossman, U.S. Department of Agriculture, Soil Conservation Service at Lincoln, Nebraska; Benjamin F. Hajek, Auburn University; Roger Hanson, North Carolina State University; Fawzi Karajeh, University of California at Davis; Jean A. Molina, University of Minnesota; Gary B. Muckel, U.S. Department of Agriculture, Soil Conservation Service at Lincoln, Nebraska; Mathias J. Romkens, U.S. Department of Agriculture, Agricultural Research Service at Oxford, Mississippi; C. Ford Runge, University of Minnesota; David L. Schertz, U.S. Department of Agriculture, Soil Conservation Service at Washington, D.C.; Steven J. Taff, University of Minnesota; and Ward B. Voorhees, U.S.
Department of Agriculture, Agricultural Research Service at Morris, Minnesota.
The committee is particularly grateful to Christopher D. Koss, President of the J. N. ''Ding" Darling Foundation, Key Biscayne, Florida, for his generous assistance in providing the four Ding Darling cartoons that help illustrate this report.
The committee also acknowledges the special efforts of Amy Gorena, who served as a senior project assistant during the early stages of the study; Michael Hayes, who provided editorial expertise during development of the manuscript; and Rolla Chuang, who assisted as a student intern sponsored by the Midwest Universities Consortium for International Activities, Inc.