Tropical Soils: Properties and Management for Sustainable Agriculture

292 Pages·2003·15.22 MB·English

by  Anthony S. R. Juo

TROPICAL SOILS
Topics in Sustainable Agronomy
Series Editors
Rattan Lal
Pedro Sanchez
Malcolm Sumner
Marilyn E. Swisher
P.B. Tinker
Robert E. White
Chemistry of Variable Charge Soils
T.R. Yu
Sodic Soils: Distribution Properties, Management, and Environmental
Consequences
M.E. Sumner and R. Naidu
Managed Ecosystems: The Mesoamerican Experience
L. Upton Hatch and Marilyn E. Swisher
Solute Movement in the Rhizosphere
P.B. Tinker and P.H. Nye
Tropical Soils: Properties and Management for Sustainable Agriculture
Anthony S.R. Juo and Kathrin Franzluebbers
TROPICAL SOILS
Properties and Management
for Sustainable Agriculture
Anthony S.R. Juo
Kathrin Franzluebbers
OXFORD
UNIVERSITY PRESS
2003
OXFORD
UNIVERSITY PRESS
Oxford New York
Auckland Bangkok Buenos Aires Cape Town Chennai
Dar es Salaam Delhi Hong Kong Istanbul Karachi Kolkata
Kuala Lumpur Madrid Melbourne Mexico City Mumbai Nairobi
Sao Paulo Shanghai Taipei Tokyo Toronto
Copyright © 2003 by Oxford University Press, Inc.
Published by Oxford University Press, Inc.
198 Madison Avenue, New York, New York, 10016
www.oup.com
Oxford is a registered trademark of Oxford University Press
All rights reserved. No part of this publication may be reproduced,
stored in a retrieval system, or transmitted, in any form or by any means,
electronic, mechanical, photocopying, recording, or otherwise,
without the prior permission of Oxford University Press.
Library of Congress Cataloging-in-Publication Data
Juo, A.S.R.
Tropical soils : properties and management for sustainable agriculture
/ Anthony S.R. Juo and Kathrin Franzluebbers.
p. cm.
Includes bibliographical references (p. ).
ISBN 0-19-511598-8
1. Soils-Tropics. 2. Sustainable agriculture-Tropics. I.
Franzluebbers, Kathrin. II. Title.
S599.9.T76 J86 2003
634.4'713-dc21 2002010390
9 8 7 6 5 4 3 2 1
Printed in the United States of America
on acid-free paper
Preface
There are many images of agriculture in the tropics: the luxuriant cash
and tree crop plantations on the rich volcanic soils in Latin America and the
Pacific Islands, the endless rice paddies on the fertile alluvial soils in tropical
Asia, the vast savanna grasslands in sub-Saharan Africa where the nomadic her-
ders roam, and the millions of slash-and-burn farmers and their families who
derive their livelihood from the acidic infertile soils throughout the humid tropics.
For several centuries, the tropical world has been a generous provider for a wide
range of agricultural and forestry products for the affluent societies in the tempe-
rate regions; yet an overwhelming majority of the human population in the tropics
today remains undernourished and impoverished.
During past decades, attempts to mimic industrial food production systems of
temperate regions have met with limited success. There is now abundant evidence
depicting that large-scale land clearance for crop and livestock production in the
humid tropics could transform the once lush green tropical forests into human-
made deserts. On the poorly buffered kaolinitic soils, continuous cropping and
chemical fertilization could lead to severe compaction and acidification after only
a few years to a level detrimental to plant growth. Agronomists and ecologists
now recognize the fragility of tropical ecosystems and more research is being
conducted to better understand the structure and function of natural ecosystems
in terms of species diversity, energy flow, and nutrient cycling, and their applica-
tion to the development of sustainable and productive agricultural ecosystems in
the tropics.
This book is intended for a multidisciplinary readership including agricultural
and environmental planners, extension workers, farmers, as well as teachers and
vi Preface
students of tropical soil science. It consists of two parts. Part I deals with basic
considerations of soil science. Part II deals with the properties and management of
major arable soils in relation to the development of ecologically and economically
sustainable farming practices in the tropics.
A.S.R.J. wishes to thank many friends and colleagues at the International
Institute of Tropical Agriculture (IITA), University of Ibadan and University
of Ife in Nigeria, and the Tropical Soils programs at Texas A&M University,
North Carolina State University, Cornell University, and University of Hawaii.
Their collaboration and interactions throughout the years have been a constant
source of knowledge and inspiration, which in many ways has influenced the
content of this book. He also wishes to acknowledge the Rockefeller
Foundation for awarding a month-long residency at the Bellagio Center on
Lake Como in Italy. The tranquil and scholarly environment at the Center has
allowed him to read, think, and write a significant portion of this book without
interruption.
Contents
Part I. Basic Considerations
1. The Tropical Environment 3
1.1 Climate and vegetation 4
1.2 Agro-climatic zones 7
1.3 Farming systems 10
1.4 Historical lessons 14
1.5 Summary 15
2. Mineralogy 17
2.1 Rocks and minerals 17
2.2 Primary minerals 18
2.3 Secondary minerals 20
2.4 Summary 26
3. Soil Chemistry 28
3.1 Surface and charge properties of soil colloids 28
3.2 Retention of ions on colloid surfaces 30
3.3 Soil acidity and toxicity 37
3.4 Alkalinity, salinity, and sodicity 41
3.5 Summary 46
4. Soil Physics 47
4.1 Soil texture 47
4.2 Soil structure and soil aggregation 50
viii Contents
4.3 Bulk density, porosity, and pore-size distribution 54
4.4 Soil-water retention characteristics 57
4.5 Infiltration and permeability 63
4.6 Water movement 65
4.7 Soil solution 66
4.8 Solute movement 67
4.9 Soil aeration 68
4.10 Soil temperature 69
4.11 Summary 69
5. Soil Biology and Microbiology 71
5.1 Soil microflora 72
5.2 Soil fauna 81
5.3 Summary 87
6. Soil Fertility 88
6.1 Soil chemical fertility 90
6.2 Soil physical fertility 99
6.3 Soil biological fertility 103
6.4 Summary 107
7. Soil Formation and Classification 108
7.1 Soil formation 108
7.2 Pedological classification of soils 110
7.3 Technical soil classification schemes 125
7.4 Summary 129
8. Major Arable Soils of the Tropics: A Descriptive Grouping
Based on Clay Mineralogy 131
8.1 Kaolinitic soils 132
8.2 Oxidic soils 133
8.3 Allophanic soils 133
8.4 Smectitic soils 133
8.5 Production potential and limitations 135
8.6 Summary 136
Part II. Properties and Management
9. Soil Management: An Overview 139
9.1 Tillage and seedbed preparation 139
9.2 Replenishing soil nutrients 141
9.3 Soil moisture management 145
9.4 Maintenance of soil organic matter 147
9.5 Landscape approach to soil and water management 150
9.6 Summary 151
10. Properties and Management of Kaolinitic Soils 152
10.1 Properties and use of kaolinitic soils 152
10.2 Traditional and modern land-use systems 154
Contents ix
10.3 Soil physical constraints and management 155
10.4 Soil chemical constraints and management 174
10.5 Summary 185
11. Properties and Management of Oxidic Soils 187
11.1 High-base-status and low-base-status oxidic soils 187
11.2 Physical and chemical properties 188
11.3 Use and management 193
11.4 Soil erosion 200
11.5 Effect of continuous cultivation on soil properties 202
11.6 Alternative land-use systems 205
11.7 Summary 207
12. Properties and Management of Smectitic Soils 209
12.1 Properties of smectitic soils 210
12.2 Use and management of smectitic soils in wetter regions 212
12.3 Use of acid sulfate soils 223
12.4 Use and management of smectitic soils in drier regions 224
12.5 Summary 228
13. Properties and Management of Allophanic Soils 229
13.1 Properties of allophanic soils 229
13.2 Use and management of allophanic soils 234
13.3 Summary 237
14. Soils and Sustainable Agriculture: Ecological Considerations 238
14.1 The ecosystem concept 240
14.2 Agroecosystems 243
14.3 Summary 252
Appendix. Physical and Chemical Properties of Selected Soil Profiles 255
References 267
Index 275