Food and Population in a Northeast Thai Village 0824815181, 082481570X

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MONOGRAPHS OF THE CENTER FOR SOUTHEAST ASIAN STUDIES KYOTO UNIVERSITY ENGLISH-LANGUAGE SERIES, NO. 19

Food and Population in a Northeast Thai Village

MONOGRAPHS OF THE CENTER FOR SOUTHEAST ASIAN STUDIES KYOTO UNIVERSITY ENGLISH-LANGUAGE SERIES, NO. 19

Food and Population in a Northeast Thai Village BY

Hayao Fukui TRANSLATED BY

Peter Hawkes

H UNIVERSITY OF HAWAII PRESS Honolulu

© 1993 The Center for Southeast Asian Studies All rights reserved Printed in the United States of America 93 94 95 96 97 98 5 4 3 2 1 Library of Congress Cataloging-in-Publication Data Fukui, Hayao. [Donden-mura. English] Food and population in a Northeast Thai village / by Hayao Fukui ; translated by Peter Hawkes. p. cm. — (Monographs of the Center for Southeast Asian Studies, Kyoto University ; 19) Includes bibliographical references (p. ). ISBN 0-8248-1518-1 (cloth : acid-free paper). — ISBN 0-8248-1570-X (paper : acid-free paper) 1. Food supply—Thailand—Case studies. 2. Rural population-Thailand—Case studies. 3. Villages—Thailand—Case studies. I. Title. II. Series. HD9016.T552F8513 1993 363.8’09593—dc20 93-25470 CIP The publication of this book was financed in part by a Grant-in-Aid for Publication of Scientific Research Results from the Ministry of Education, Science, and Culture ofjapan. The map on the cover is part of the map of Asia by Cornelius de Jode, 1593 (reproduced courtesy of the Kobe City Museum). University of Hawaii Press books are printed on acidfree paper and meet the guidelines for permanence and durability of the Council on Library Resources. Designed by Paula Newcomb

To Harumi

Contents

ix

Figures Tables

xiii

Foreword

xvii

Preface

xix

Introduction: T h e Purpose of the D D Village Study and This Book 1. TheDD Village Study 2. “Agroecology” 3. The DD Study as an Area Study 4. Note on the Text and Terminology

1 1 5 11 16

1.

Northeast Thailand 1. The Agricultural Landscape 2. A Statistical View of the Northeast 3. Nature and Agriculture 4. People and History

17 17 20 23 26

2.

D D Village and Its Surroundings 1. Khon Kaen in the Northeast 2. DD and Its Neighboring Villages 3. Village Life

37 37 46 64

3.

Fertility and Mortality 1. Changes in the Village Population 2. Study Methods and the Nature of the Data 3. Mortality 4. Fertility 5. Estimation of Net Migration for a Closed Population

82 83 87 88 97 104

4.

Migration 1. The Family History Survey 2. Periodization of DD ’s Demographic History

114 114 118

vii

viii

CONTENTS

3. Reasons for Migration 4. Reasons for Migration Reviewed

122 143

5. The Environment and Technology of Rice Production 1. The Natural Environment 2. Current Rice Growing

150 150 173

6.

191 191 193 222

Evaluation of Rice Production 1. Instability of Rice Production 2. A Simulation Model of Rice Production 3. Labor Productivity

7. Occupations Other than Rice Growing 1. Cultivation of Upland Crops 2. Vegetable Cultivation and Gathering of Natural Products 3. Stock Rearing 4. Off-Farm Employment

240 240

8. Subsistence and Market Economies 1. The Village Economy in Mizuno’s Time 2. Economic Conditions in the 1980s

273 273 278

9.

Population, Land, and Food 1. The Rice Balance 2. The Opening of the Middle and High Fields 3. Migration in Search of New Land

297 297 304 309

Appendix 1: Basic Units of the Domestic Budget 1. Households and Interhousehold Cooperation 2. Units of Livelihood Maintenance Larger than the Household

329 329

Appendix 2: The Use ofPlants in DD

341

Appendix 3: Notes on the Process of Emigration in Search of Land (Ha Na Di) to MN Village, Udon Thani Province, by Yukio Hayashi 1. Introduction 2. A Record of Interviews in MN 3. Ha Na Di

352 352 353 366

244 252 259

335

Notes

371

Bibliography

407

Index

415

Figures

1-1.

The Four Regions of Thailand

18

1-2.

Topography of the Kho rat Plateau and Its Surroundings

24

2-1.

Isohyet of Drought Days, May-October, Khorat Plateau

38

2-2 .

The Chi Floodplain in the Khon Kaen Area

41

2-3.

Factories in the Khon Kaen-Tha Phra Area

47

2-4(a). Neighboring Villages Surveyed

50

2-4(b). Per Capita Acreage of Paddy Land

50

2-4(c). Proportion of Total Population Commuting to Work

51

2-4(d). Proportion of Upland in Total Arable Area

51

2-5(a). Land Use in the Vicinity ofDD, 1954

54

2-5(b). L a n d U s e i n t h e Vicinity of DD, 1967

54

2-6.

Arable Land in the Area of DD

57

2-7.

Daily Measured Temperatures and Rainfall in DD, 1983

66

2-8.

Seasonality of Agricultural Working Hours

69

2-9.

Labor Distribution in One Household

70

3- l(a). Village Population, 1964

86

3-l(b). Village Population, 1983

86

3-2.

Life Table lx Values for the 871 Children as a Single Cohort

93

3-3.

Life Table lx Values for the Children Data in 10-Year Cohorts

95

3-4(a). Age-Specific Fertility for Women in the 5-Year Cohorts

100

3-4(b). Age-Specific Marriage Rate of the 5-Year Cohorts

101

3-5.

Age-Specific Fertility in Marriage ofthe 5-Year Cohorts

102

3-6.

Age-Specific Fertility in Marriage of the 5-Year Cohorts, by Period

103

ix

X

3-7. 4-1.

FIGURES

Comparison of the Projected and the Actual 1984 Population

109

Estimated Village Population Change

117

4-2(a). Migration According to the Family History Survey (Annual)

120

4-2(b). Migration According to the Family History Survey (5-Year Moving Average)

120

4-3.

Immigration, by Reason (per 10 Years)

123

4-4.

Emigration, by Reason (per 10 Years)

124

4-5(a). Net Migration, by Reason (by Period)

127

4-5(b). Net Migration, by Reason (per 10 Years)

128

4-6.

Emigration for Employment and Reimmigration after Employment (per 10 Years)

132

5-1.

Ten-Day Rainfall at Tha Phra and Rice Yields in DD

151

5-2.

Thirty-Day Moving Averages of Rainfall (Tha Phra, 1978-1983)

5-3.

Generalized Stratigraphy of the Hill and Floodplain Regions Around DD

5-4.

152 155

Schematic Cross Section of Stratigraphy from the Chi River to the Southern Hill Region

156

5-5.

Topographic Zones in the DD Area

156

5-6.

Spatial Distribution of the Fertility Classes

162

5-7 .

Relation between Paddy Yield and Fertility Class under Presumably Slight Water Stress

5-8. 5-9.

163

Distribution of Potential Yields Estimated from Soil Fertility

165

Paddy Plot Map of the DD Area

166

5-10. Typical Ownership Boundaries of Paddy Plots in a Nong

168

5-11. Size Distribution of Plots in Nong Simban

169

5-12. Comparisons of Observed Water Depth in Paddy Plots

171

5-13. Parameter D2 and Patterns of Seasonal Variation in Water Conditions in Paddy Fields

172

FIGURES

xi

5-14. Spatial Distribution ofD 2 Parameters in Nong Simban

173

5-15. Changes in Standing Water and Drought Damage

174

5-16. Daily Rainfall and Progress of Seeding, Plowing, and Transplanting

177

5-17. Relation between Dates of Transplanting and Heading, by Variety Group

179

5-18. Relation between Landform and Cropping Calendar

181

5-19. Schematic View of a Nong

182

5-20. Growth Stages of Rice, by Variety

184

5-21. Relation between Paddy Weight and Total Dry Weight

185

5-22. Frequency Distribution of Yield Grades in 1981 and 1983

189

6-1.

Probability Distribution of 5-Day Rainfall

196

6-2.

Comparison of Synthesized and Actual Rainfall

197

6-3.

Outflow Rate from the Nonpaddy Area in a Nong

201

6-4.

Moisture-pF Curve for Soil Textural Classes

204

6-5.

Moisture-Retention Structure ofSoil Textural Classes

205

6-6.

Variation of Evapotranspiration Rates according to Growth Stage of Wet Rice

209

6-7.

Validation of Estimated Water Depth in Paddy Plots

210

6-8.

Growth Stage and Yield Reduction Rate Due to

6-9.

Moisture Stress

213

Yield Reduction Due to Shortening of Growth Duration

214

6-10. Validation of Estimated Yield Reduction, by Topographic Class

215

6-11. Validation of Estimated Yield Reduction for Entire DD Paddy Area 6-12. Period of Estimation and Average Yield-Reduction Rate

216 217

6-13. Frequency Distribution of Yield-Reduction Rates, by Topographic Class

218

6-14. Cumulative Rainfall and Onset of Flooding

221

6-15. Daily Working Hours in Transplanting, Mr. Somkhit

230

6-16. Daily Working Hours in Harvesting, Mr. Somkhit

231

6-17. Simulated:Brogress ofTransplantingDependingon Water Status ancl Labor Force 6-18. AnnualiBr.oportipns of Paddy

233 reasJ3nplanted,.by Cause

234

6-19. Labor Force perAblhit Area and 100-Year-Average Plantable Are'a ■

236

6-20. Relation between Paddy Area per Worker and Annual Income

238

7-1.

Land Use in the t)D Area

241

7-2.

A Vegetable Garden (Suan) Plan

245

7-3.

Examples>of VegetableGardentPlantingSequences

246

9-1.

Rice Balanceratthe 'Lime of our Survey

298

9-2.

Paddy Land Reclaimed by the Mid-1930s

30.1

9-3.

Rice Balance infthe 1930s

302

9-4.

Relation between Reclamationtof High and'Middle Paddy Lands inrthe. 1.940s andtt'he 1'00-Year Average Plantable Area

9-5.

■

305

Relation betweentOperated Area and 100-Year-Average Plantable Area When High PaddyaFields'Only Are Farmed

307

9-6.

EstimateddiffectsitoflmprovediQuTfivation Techniques

309

9-7.

GenealogicaFRelatibnships befjve'entSZa.Wa Di Migrants Who Left the Village after 1964

9-8.

Paradigm:6fthe Relation between.Population, Land, and Food at the Village Level.

9-9.

312 318

Changes.in the Relation between. Population,. Land, and Food

A3-1. Locations of Frontier Villages

321 353

Tables

1-1.

Land to Population Ration, by Continent

1-2.

Increase in Population and Arable Land Area by Continent, 1968-1984

1-3.

11 13

Changes in Population and Production, Area, and Yield of Rice in Rice-growing Countries in Asia, 1961-1965 to 1983-1985

15

1-1.

Gross Regional Production (GRP) and Income

22

2-1.

Calendar of Events

63

2-2.

Cooking Methods and Ingredients

74

2-3.

Expenditure on Food Purchases (Period: 22 October10 December 1981)

77

3-1.

Average Rate of Increase in Village Population

84

3-2.

Summary of the Children Data

90

3-3.

Cohort Life Table (871 Children = Single Cohort)

92

3-4.

Ten-Year Cohort Life Tables for the Children Data

94

3-5.

Estimated Mortality at Birth Based on 1970 Thai National

3-6. 3-7.

Census

96

Summary of the Mothers Data

98

Age-Specific Fertility of Five-Year Cohorts of the Mothers Data

99

3-8.

Percentage of Five-Year Cohorts Who Practice

3-9.

Estimated Migration for Village Residents as of 1964,

Contraception

104

Based on Closed Population

105

3-10. Estimated Births during 1964-1984 by Women Resident in DD in 1964

107

xiii

xiv

TABLES

3-11. Projected 1984 Population of Children of Mothers Resident in DD in 1964

108

3-12. Sample Calculation of Natural Population Growth Rate

111

3-13. Predicted Migration Based on a Closed Population

112

4-1.

Comparison of Populations Counted and Estimated from Family History Survey

115

4-2(a). Indirect Estimation of Mobility in 1964-1983

118

4-2(b). Mobility in 1964-1983 Based on Family History Survey

119

4-3.

Periodization of DD ’s Demographic History

121

4-4.

Origins and Destinations of Migrants to New Land

130

4-5.

Sex and Age Structure of Emigrants to New Land

131

4-6.

Sex, Age, and Marital Status of Emigrants and Families Leaving for Employment

4-7.

134

Sex, Age, and Marital Status of Immigrants and Families Returning from Employment

135

4-8.

Destinations of Emigrants Leaving for Employment

136

4-9.

Origins of Immigrants Entering for Marriage and Destinations of Emigrants Leaving for Marriage

4-10. Residences and Destinations of Ook-hien Migrants

140 142

4-11. Migration for Purposes of Education, Monkhood, or Military Service

147

5-1.

Rainfall at Tha Phra, 1978-1983

153

5-2.

Morphologic Properties of Stratigraphic Layers and Clay Mineral Compositions

5-3.

Correspondence between Typical Soil Profiles and Sedimentary Layers

5-4.

159 160

Mean Values of Physicochemical Properties of Soil Fertility Classes

161

5-5.

Topography and Varieties Selected, 1983

180

5-6.

Typology and Land Conditions of Rice Cultivation

182

5-7.

Yields Assessed by Cutting Surveys (1981 and 1983)

183

5-8.

Yield Components According to Variety (1983)

183

TABLES

5-9 .

XV

Correlations between Yield Components, by Variety Group (1983)

186

5-10. Proportions of Paddy Land Planted in 1981 and 1983

188

5-11. Comparison of Yields in 1981 and 1983, by Variety Group

190

6-1.

Annual Variations in Rice Production (1960-1964)

192

6-2.

Annual Variations in Rice Production (1978-1983)

193

6-3.

Calculation of Standard Evapotranspiration

208

6-4.

Validation of Simulated Cropping Calendar (Number of 5-Day Periods from the First 5-Day Period of April)

212

6-5.

Labor Efficiency in Planting (1983, Chinawon Family)

223

6-6.

Division of Labor between Husband and Wife during Transplanting (Chinawon family, Youngest Daughter and Husband) (Unit: 10 Minutes)

6-7 .

224

Division of Labor between Husband and Wife during Harvesting (Chinawon Family, Youngest Daughter and Husband)

227

6-8.

Labor Efficiency in Reaping (1983, Chinawon Family)

228

6-9.

Net Labor Efficiencies in Rice Growing

229

6-10. Estimated Production Increment with Expansion of Area 7-1.

237

Input of Production Materials in Vegetable Growing (14 Plots, 12 Households)

247

7-2.

Sale and Barter of Vegetables (14 Plots, 12 Households)

248

7-3.

Products Directly Marketed by Villagers

250

7-4.

Sex, Age, and Transactions of Water Buffalo (42 Sample Households)

253

7-5.

Birth and Death Rates of Water Buffalo, Cattle, and Horses 256

7-6.

Pig Transactions and Prices

7-7.

Characteristics of 42 Sample Households Keeping Livestock 257

7-8.

Occupations of Nonfarming Household Heads

261

7-9.

Self-employed Households

262

257

7-10. Householders in Stable Wage Labor

266

7-11. Householders in Unstable Wage Labor

268

xvi

TABLES

8-1.

Cash Economy of Farm Households, 1964

275

8-2.

Household Cash Expenditures, 1964

276

8-3.

Farming Household Economies in Average Years around 1964, Including Rice Production

278

8-4.

Occupations of Householders (1983)

279

8-5.

Occupations of Nonhouseholders (1983)

279

8-6.

Village Economy, 1980-1981

282

8-7.

Changes in Village Economy between the 1960s and 1980s

286

8-8.

Ownership of Expensive Goods

288

8-9.

Items of Domestic Expenditure (1980-1981)

289

8-10. Number of Villagers Receiving an Education

290

8-11. Economic Statistics and DD ’s Economy

293

8-12. Real Economic Growth Rates of Nation, Region, and DD

294

9-1.

Comparison of Rice Balance in DD in 1930s and 1980s

303

9-2.

Household Emigrations, 1956-1964 (Households/People)

310

9-3.

Farmland Holdings and Family Composition of Ha Na Di Emigrants from 1965

311

Foreword

This is the first of a series of reports to be derived from the village study conducted by an interdisciplinary research team from the Center for Southeast Asian Studies, Kyoto University, at the Thai-Lao hamlet that we will call DD in Changwat Khon Kaen, Thailand, over a period of nineteen months between 1981 and 1983. With his extraordinary enthusiasm, Professor Fukui planned and initiated the project, made all the necessary on-the-spot arrangements for the group of more than twenty researchers in different disciplines, lived in the village himself for virtually the whole period of the project, and has now authored this report of the results of his ambitious undertaking. As merely the symbolic leader of the DD project, I am very pleased to see that his report, of which the original was published in Japan in 1988, is now to be made available in English, thereby becoming accessible to the wider circle of readers who are concerned with the fate of people now exposed to relentlessly rapid social change. The present volume may be unique in being a report of. a joint research project written by a single author. Naturally, it is not intended to be comprehensive; rather, it is a coherent synthesis by the project planner and leader of a variety of findings made by his colleagues, who have conducted their respective research with differing methods and expectations. It presents an interpretation of what has happened and is now happening in a peasant society in Northeast Thailand. By comparing the observations made in this volume with those to be presented in subsequent volumes, the reader may gain a deeper understanding of the Thai-Lao community. On behalf of the DD village study team, I wish to express our heartfelt thanks to the National Research Council of Thailand, which generously sponsored the project. I also wish to thank our Thai colleagues, without whose thoughtful cooperation the project could never have been completed. The dedicated help given by our charming Thai research assistants is also noted with great appreciation. Last but not least, our sincere thanks goes to each of the villagers of DD, who so kindly welcomed us into their community and made our prolonged stay in that Thai-Lao village so pleasant and memorable. Yoneo Ishii

xvii

F Preface

I began this book with two intentions. One of these was to bring the viewpoint of “agroecology” into the field of agricultural research, the other to contribute to area study as an agricultural scientist. Only the reader can judge whether I have achieved these two aims. I can only hope that I have not fallen between two stools but have at least provided a salutary example by which those trained in agricultural science and aspiring to area study can learn from my mistakes, even if it leads them to abandon area study entirely. I should point out that, as is mentioned in the introduction, this book does not tell the whole story of the DD village study. Other publications are planned of works that take a different stance and employ data not included here. As this is the first book to appear on the DD study, however, it is unavoidable that the study will to some extent be judged by it. In this, I should ask the forbearance of the other participants in the study, especially as I have written as a single author and as a challenge to the kind of interdisciplinary study that tends to become a collection of papers. I am not sure whether such a claim can constitute a justification for the DD study, but, whatever the reception afforded this book and its successors, I consider this study to have been a success. The main, reason for this is that, aside from the academic significance of the study, most of the participants seem to have enjoyed it. Flippant though this may sound, I believe it is important. I continually advised the younger researchers not to do anything that they did not find interesting since I believe that basic research should not be conducted with a view to the everyday world or immediate benefit. Such basic research may well eventually benefit people in the everyday world, whereas the opposite approach tends to kill the goose that lays the egg, even if the egg may not be golden. This approach is, however, not generally popular. The students of Khon Kaen University who assisted us asked what use our activities were to the villagers, and, of course, the villagers themselves did not understand what we were doing. We were' seen as taking advantage of

xix

XX

PREFACE

their naive kindness toward strangers, and it was even reported in the local newspapers that our purpose was to search for uranium ore. To the extent that basic research is not accepted by the public at large, those who perform it must be humble. In that they have no intention of producing something of immediate benefit, they must show humility toward the taxpayers and the villagers. I told myself that I must not respect learning so much that I would hurt the feelings of the villagers. If, however humble I might be, they would not allow me to conduct my research, I would have no choice but to abandon it. Ten or so Japanese lived in DD. Some people teased us that the relationship between them and the villagers would itself become the subject of an anthropological study. Professor Prasert, one of the Thai scholars who participated 'in the study, described the Japanese researchers as being like an army battalion. He was probably referring to a Japanese character trait, but I believe that the cohesiveness of the participants was not only due to this but also greatly affected by the magnanimity and forbearance of each participant. Another point about the DD study is that a new methodology was attempted. Some may claim that there is nothing very novel about it or that they could have made a better job of it. But it may not be too presumptuous to liken ourselves to Columbus: although he failed to reach the American mainland, it may not have been discovered until much later than it was had he not made the attempt. The holistic approach may be old-fashioned in the field of anthropology, but in an interdisciplinary village study, of which so few have been performed, its significance is undeniable. At the very least, this is true from the standpoint of agricultural science. Whatever the reception afforded this book, I personally feel that I have accomplished a once-in-a-lifetime endeavor. My feeling owes much to the other participants in this study. Their enthusiasm has been a tremendous encouragement, and their generosity has allowed me to use large amounts of their data and results, both published and unpublished, throughout this book. All chapters have been looked over by the relevant individuals, but the accounts of the findings are mine alone, and in places my interpretations differ from those of the original researchers. Thus, this book is at the same time the product of all participants in the DD study and also my own work. Such ambiguity seems inevitable in any attempt to describe the results of an interdisciplinary study coherently. I have deliberately refrained from acknowledging my fellow participants individually. There are, however, three people who have helped me directly with the preparation of this book. They are Dr. Yasuyuki Kohno, who ran the simulation model many times at my request; Mr.

PREFACE

xxi

Shinji Suwa, who helped me prepare the family history data; and Mr. Kazuo Funahashi, who arranged the economic data and subsequently prepared the English version of the figures. I must also mention the great support afforded me by the Center for Southeast Asian Studies of Kyoto University, a singularly unconventional institution. This may be disconcerting to many, in that I am the product of this center; but there is no doubt that I would not be what I am and the book would not have been written had the center not existed. Professor Yoneo Ishii, a former director of the center, took on the role of representative of the DD study project and has also written the foreword to this book. Professor Yoshihiro Tsubouchi and Associate Professor Tadataka Igarashi advised me on methods of population survey and analysis, and Professor Yoneo Ishii, Associate Professor Yumio Sakurai, and Professor Yoshikazu Takaya advised me on religion and peoples. Besides giving advice and guidance, staff at the center helped me by taking the burden of routine duties off my shoulders and ignoring my neglect of duty during the writing of this book. In Thailand, I must thank the National Research Council of Thailand for their understanding and cooperation over the many years of the DD study. Particularly important for this study were two seminars—in 1981 and 1986, before and after the field research—that were held in conjunction with the Japan Society for the Promotion of Science (JSPS) and at which the study was discussed and we received much valuable counsel from many Thai scholars. During the survey, we were greatly helped by Khon Kaen University and the provincial administrations of Changwat Khon Kaen and Changwat Maha Sarakham. In particular, I would like to express our gratitude to Professor Noppadon Thongsophit, then rector of Khon Kaen University, and Professor Kavi Chutikul, then dean of the Faculty of Agriculture. Six students in 1981 and seven in 1983 lived with us in the village and acted as assistants. I shall not name each of them here, but we shall never forget their self-sacrificing assistance and that of Pakorn Kunarak. They were companions who, quite literally, shared with us food and all the joys and griefs of life. Among them, we shall never forget Warida Nanthayaphirom, a young woman who, although aware of her approaching death from leukemia, strove to remain cheerful and keep others from realizing. Countless of the villagers also deserve our gratitude. Among them, I should mention Headman An and his successor, Mr. Pheng, for their sincere cooperation. Our most important informant was Pho Khen (Pho, which means “Father,” is a term of respect for an older man), who had an outstanding memory. Pho Ma defended us physically from a drug addict intruder. We shall not forget the village elders, the late Pho

xxii

PREFACE

Han, the late Pho Tan, Pho Sang, and the devout Pho Nikhon, who helped us in ways we knew nothing about, and our landlord Pho Uan, a most friendly and pleasant man. Pho Tha, who had lived next door to the late Koichi Mizuno during his stay in DD, had moved to Changwat Udon Thani “to search for new land” (ha na di). When we visited his new village, he took our hands and greeted us with tears of joy. Our debt to Mizuno was not only for the data he left us; the relationships he built with the villagers were invaluable to our survey. All the village attended a memorial service held for him at the village monastery immediately before we began our survey. Here we express our hopes for his eternal happiness.

Introduction: The Purpose of the D D Village Study and This Book

This book presents a discussion of agroecology at the village level, based on the results of an interdisciplinary study carried out in the village that we call DD, in Northeast Thailand. One aim of this study was to find a new methodology for agricultural research, particularly in developing countries, to demonstrate its effectiveness, and to invite criticism. The other was to make some contribution to the area study of Southeast Asia from the standpoint of agricultural science. This introduction first describes the overall nature of the DD village study, then introduces the viewpoint and methodology of the somewhat unfamiliar term agroecology. It also outlines what this book hopes to say within the framework of Southeast Asian studies.

1. The DD Village Study The DD village study was carried out under the direction of Yoneo Ishii of Kyoto University.1 Fieldwork occupied 7 months of 1981 and all of 1983. In the first of these years, there were sixteen Japanese and three Thai workers and, in the second, twenty Japanese and two Thai. With a few exceptions, each researcher was resident twice, for several months on each occasion. The specialties of the participants were anthropology, sociology, economics, geography, environmental science, and the various fields of agricultural science. Some explanation may be necessary as to why so many researchers from so many fields were involved in the study of a single village. Research involving residence in a village is a method used not only by cultural anthropologists but also by, for example, sociologists, agri-

1

2

INTRODUCTION

cultural economists, and geographers. However, the cultural anthropologists who have made this a recognized method assume in their approach that they will attempt to view the village as a whole and to identify its component elements and their interactions. This is known as the holistic approach, and it necessitates a comprehensive and detailed study that, as anthropologists themselves acknowledge, is not always possible. One basic reason for this is the general use of the anthropological fieldwork method known as “one man, one village, one year” (Hackenberg, 1974). It was our intention to break the mold of conventional research methods by reexamining a village that had been studied in 1964 by Koichi Mizuno, this time with a research team including both social and natural scientists. This accounts for the participation of the social scientists and, in particular, the anthropologists in this study. For those involved in the natural sciences, particularly agricultural science, to live in a village with social scientists was a completely new departure. It meant that they had temporarily to abandon conventional agricultural research, which has developed mainly through an experimental methodology, to concentrate on field studies. It was not at first clear whether they would be able to do more than assist the social scientists, much less produce work capable of standing by itself in the discipline of agricultural science. We do, however, consider that examination of the various problems of the agriculture of developing countries requires researchers to study these problems systematically and holistically in the field, rather than in an insulated laboratory or test site. Although it cannot be said that a suitable methodology for this has yet been developed, we have confirmed the importance of village residence for the systematic understanding of agriculture at the village level. These approaches, of the social and natural scientists, were brought together in a comprehensive and systematic village-level study. Thus, the study was conducted with each specialist realizing that any understanding that was limited to his or her own field and existing specialist knowledge would be inadequate. The residence of an interdisciplinary team in a village creates a markedly different situation than the presence of a single cultural anthropologist does. In a village of 176 households, there were always around ten foreigners, along with five or six Lao-speaking student assistants, renting two or three houses and some rooms, living with the villagers, and meeting them each morning and evening. The three maids, the four permanently employed informants/advisers, and the five or six seasonally employed laborers were all from the village. In the village, a kinship group is known as a sum; our large group was known as the sumjiphun or “Japanese sum.”

THE P U R P O S E OF THE STUDY

3

The main work of the social scientists was interviewing. They visited each household, attended all rituals and meetings, and visited the monastery regularly. One visited neighboring villages and went to the market and administrative offices in the town. One natural scientist set up a tripod and made surveys. Food was inspected, water buckets counted, well water sampled. The agricultural scientists left home in the same way as the villagers, napped outdoors as they did, and returned in the evening with the water buffalo. On one occasion, there was a visit to the parent village of DD in another changwat (province) and, on another, a visit to a pioneer village established by villagers who had left DD. There seemed to be no major problems in how we adapted to the village and how the villagers accepted us. One reason for this that must be mentioned was the continuing feeling of goodwill toward Mizuno, who had been resident in the village in 1964-1965; our debt to him is considerable. The second reason was the choice of assistants who spoke Lao. They functioned as “honest brokers” between the villagers and the study team, thus reducing the perceived gulf between the two, and successfully removed the impression of “otherness” created by those members of the study team who spoke standard Thai. Nevertheless, the relationship between the villagers and the study team was quite different from that between villagers and a single researcher. The large number of researchers was in itself not felt to be a disadvantage; rather, it may have ameliorated some of the adverse effects that might have arisen had there been a single researcher. The researchers, who were of various personalities and ages, came into contact with the villagers, similarly varied in personality and age, forming a complex pattern of routes of association between the two groups through which a great variety of information could pass to and fro. Not only did this make for unprecedented ease in preventing facts from being misunderstood or ignored, but it also reduced the risk of partial judgments. One important element that determines the success or failure of an interdisciplinary study is the understanding among the team members. This mutual understanding came about naturally as the members lived together through the long period of the field study. At that stage, however, the data had not been organized. Only the germs of ideas, based on limited data and intuitions, were being exchanged. We decided to record these in a publication known as the DD Newsletter. This continued after our return to Japan, reaching issue number 33 in December 1986. Through this, we endeavored to produce a common resource for all members, not only of data, but also of interpretations and the overall image of the village that was constructed on this basis.

4

INTRODUCTION

Results of the “Interdisciplinary” Study There have been few previous interdisciplinary village studies that have included the natural sciences. Considerable effort and ingenuity are necessary to make an interdisciplinary approach effective, with all the differences that exist in points of view and methodology between the disciplines. Above, I have briefly described our experience at each stage of planning, fieldwork, and analysis of data. However, the problems of an interdisciplinary study are not limited to these stages. The interdisciplinary nature of the study also causes problems when the final results are being prepared for publication. The researchers retain the problematics and methodology proper to their own specialties. Specific research topics are determined on the basis of these, and published results are addressed to fellow specialists and subject to peer review. Even when a researcher participates in an interdisciplinary study, these processes remain basically the same. Thus, individual researchers involve themselves with separate aspects of the village with which their specialties are concerned, addressing problems within the framework of the theories and problematics of the specialty and seeking assessment from a specialist audience. How this kind of study differs from one involving only a single discipline is that it has as its background a more comprehensive understanding of the village. The extent of this background is one yardstick of the value of an interdisciplinary study. The question arises, however, whether results that are taken back into the specialties for publication independently are the only published results of the interdisciplinary study. How —in what form — may the overall understanding that forms the “background” to the individual publications itself be published? At least in our experience of interdisciplinary collaboration, no answer has been found to these questions. No specialty exists that can completely achieve the generalization of the interdisciplinary village study. Accordingly, there is no academic paradigm that may be applied to it: there are only the paradigms of related fields. Of the related fields, it is the “holistic approach” of cultural anthropology that comes closest to providing an overall understanding of the entire village. However, the quantity and quality of the data that we gathered make it impossible to manipulate them using the paradigms of this discipline. Agroecology, in the sense used in the following chapters, is an approach that is capable of encompassing a large part — although-not all—of the overall understanding of the village. But it is not widely recognized as a separate discipline in itself. In this book, I try to demonstrate that the agricultural scientist has something to offer in the field of area study, in

5

THE P U R P O S E OF THE STUDY

contradiction to the general notion that this is a field for the humanities and social sciences. If an attempt to conduct a village residence study that includes the natural sciences has few, if any, precedents, the form in which the results are published must also be unprecedented.

Reports on DD Village and the Team Members The results of Mizuno’s work on the village are principally to be found in Mizuno (1981). The first interim report of the whole team on this study was Fukui, Kaida, and Kuchiba (1983).This was followed by two more interim reports (Fukui, Kaida, and Kuchiba, 1985, 1988). Each team member, including the Thai members, has contributed to these reports. In addition, there have been many reports authored by one or more members of the team. As almost all these are in Japanese, they will not be cited here. The members of the team, who include the authors of the reports, and their fields of specialty are as follows: project leader: Yoneo Ishii (history); coordinator: Hayao Fukui (agroecology); subleaders: Masuo Kuchiba (cultural anthropology) and Yoshihiro Kaida (hydrology); members: Anukhun Klungbunkrong (agricultural extension), Chaitat Pairintra (soil science), Kazuo Funahashi (sociology), Tomoo Hattori (soil science), Toshiyuki Imai (rural planning), Kanha Bunpromma (crop science), Teitaro Kitamura (regional planning), Toshiro Kuroda (crop science), Toshikiyo Maekawa (rural planning), Matsuji Matsuda (environmental science), Shuichi Miyagawa (crop science), Takeshi Miyazaki (agricultural economics), Haruo Noma (geography), Prasert Yamklinfung (sociology), Takahiko Takemura (cultural anthropology), Hiroshi Tsujii (agricultural economics), and Hideo Yano (animal science); graduate students: Yukio Hayashi (cultural anthropology), Yasuyuki Kohno (agricultural hydrology), Satoshi Koike (rural planning), Hiroyuki Matsufuji (soil science), and Shinji Suwa (sociology); field assistants: Pakon Kunaruk, Supit Puhual, Thanapan Thanee, Keota Mongkolsatit, Wongduan Ghutchaval, Sunee Chingjikul, Ophat Yotkaeo, Saiyon Thiptamyae, Somkiat Khonchan, Songsin Photchanachai, Uthit Huthaisong, Wiset Suwannatrai, and Warida Nanthayaphirom.

2. Agroecology This section explains the need for a comprehensive factual study of agriculture, particularly in developing countries, which might be termed agroecology, and describes the search for an appropriate paradigm for this kind of study.

6

INTRODUCTION

The Gap between Agricultural Education and Research and Actual Practice The disadvantages of the specialization of agricultural science are often noted. In the case of agricultural assistance, the criticism has been made, with some irony, that one would need to bring a dozen experts from Japan to answer the questions of a single Javanese peasant. What is necessary, it is said, is not analysis alone but also synthesis, and this comment does indeed seem pertinent. However, specialization is not something that is limited to agricultural science; it is seen in almost all fields of science. Certainly, the astonishing progress of science would have been impossible without it. Where specialization poses special problems is in the developing countries. Through the influence of the developed countries, specialization in agricultural education and research has increased in the developing countries, but often it is not linked to the agriculture practiced in the country in question. Various reasons can be adduced for this. 2 Once the gulf between agricultural education and research and actual practice in developing countries is acknowledged, what are researchers into tropical agriculture to do? Are they merely to wait for the gulf to disappear? Are there no means that they can adopt as researchers? One common reaction to the circumstances in developing countries is to discount basic research in favor of practical research. However, agricultural science is fundamentally an applied science, and all parts of it are situational. The problem of agricultural research in tropical or developing countries is not one of basic research or applications. How, then, may research be founded on specific situations? The most usual response is to find out about the physical conditions and then to discover relevant research topics on the basis of this knowledge. This answer is logical and apparently appropriate, but it is not practical. To identify research topics only on the basis of physical conditions— ignoring current agricultural practice—will frequently cause irritating mistakes. The time has passed when it was possible to judge from climate and soil conditions alone that a place was suitable for the cultivation of plantation crops, then hack one’s way through the forest with a troop of slaves. In particular, most of the cultivable land in tropical Asia is already in use, and the research topics that a researcher can identify should be ones that will point existing agriculture in a more desirable direction. The results of agricultural research will be effective only when grafted onto existing agricultural practice. To base research on location specificity must mean basing it on agriculture as currently practiced. The current state of agriculture is presented to researchers today

THE P U R P O S E OF THE STUDY

7

through agricultural statistics, the reports of the mass media, and drama and films set in agricultural villages. Researchers rarely receive feedback from agricultural extension officers, and what feedback they do receive is fragmentary. Individual researchers may have had experience as a member of a farming family or have impressions garnered from visits to rural research stations. A more penetrating source of information is reports and academic papers in the fields of cultural anthropology, geography, and area studies. It is ironic that these reports provide more useful information about the state of agriculture in a certain region than do those of researchers involved with agricultural science. Neither of these sources of information is insignificant. However, it is clear that each has its faults, and both are therefore to some extent unsatisfactory. The slogan “Back to the villages” is heard even in developing countries, but the problem is not one that can be solved by such simple appeals. To bridge the gap between research and education and the reality of agriculture, researchers need to make a systematic and comprehensive study of the state of agriculture. Regrettably, the framework of agricultural science in developed countries does not encompass a field of research that comprehensively and systematically studies the reality of agriculture. This is because, for the reasons outlined, the need for this is small. 3 In tropical countries, for the same reasons, the need is great. Accordingly, there is a need for a comprehensive study of the reality of agriculture as a field of agricultural science specific to the study of tropical agriculture. 4 Agroecology Agroecology represents an attempt to understand the state of agriculture as it really is. 5 Such an analysis is neither confined to any one discipline nor focused on just one aspect, such as the relation between soil, climate, and crops or that between land use and distance to market. Rather, it explores all the relations between all the primary factors, everything that is relevant to the form of agriculture under consideration. Therefore, agroecology is inevitably interdisciplinary. Agroecology must have its own methods and problematics to be recognized as an area of research in agricultural science. Besides the question -of recognition, the rarity of this approach in practice is related to the lack of an established framework and methods for research and of a forum in which to appraise the results of the research. While my knowledge of global trends in this kind of research is imperfect, I would like to search for an appropriate paradigm for agroecology, as the term is used in this book, in several trials that have

8

INTRODUCTION

been made in tropical Asia, principally in Thailand. One paradigm of agriculture views it basically as a biological ecosystem with the element of humanity added. In theory, the human and ecological elements are grouped together indiscriminately. This is large in conception but produces an excessively complex system and a paradigm whose effectiveness is consequently dubious. It often serves only to emphasize the complexity of the agricultural systems in traditional societies. Often when the ecosystem model is used to study an agricultural system, the human element is not considered as interacting with the ecological element in the same system but is rather treated as an element that conditions the agricultural system. In other words, many of the human elements are, strictly speaking, extrasystemic. 6 Although the term agroecology is sometimes used for such studies, crop ecology or farming ecology would be more appropriate. Sociology and cultural anthropology posit many paradigms in which a society or culture that includes agriculture is at least in part adapted to the ecological environment and as a result subject to the prevailing ecological conditions. Such is the case in classic environmental determinism and environmental possibilism, and cultural ecology is basically the same. By using such paradigms, it is possible to understand humanity’s adaptation to nature but difficult to grasp the dynamic aspect, how humanity changes nature and adapts again to the changed environment (Rambo, 1981). The two types of paradigms outlined above may be called ecosystem, models and adaptation models. Ecosystem models take human elements as their independent variables and the biological performance of crops as dependent variables; in adaptation models, the situation is reversed. Ecosystem models are useful for agricultural scientists whose primary interest is the biological performance of crops but who also want to take human elements into consideration. When such paradigms are used, the ecological elements are readily systematized, while the human elements are mentioned without particular attention to the interactions between individual variables. Adaptation models are used by social scientists whose primary interest is in society and culture but who also wish to take the effects of the natural environment into consideration. The dependent variables are understood as a whole, but the independent variables are usually dealt with unsystematically. Although the adaptation models can be used to deal with changes in agriculture, they are not suitable for this task. They are designed to describe static states and must therefore be given a set of previously unused independent variables if one intends to use them to handle changes. They are, however, incapable of handling changes arising through the interaction between ecological and sociocultural elements. 7

THE PURPOSE OF THE STUDY

9

What, then, should be done about changes in agriculture brought about by the interaction between human and ecological elements? The most obvious example is the interaction between population and agricultural production. Different interpretations of this posit diametrically opposed directions of causality. On the one hand is the notion, based on Malthus’ theory of population, that food supply determines population; on the other is the theory that increase in population density encourages intensification of agriculture (Boserup, 1965). The theory that tropical Asia is the only tropical region in the world with a high population density because it incorporates the rice-growing culture of the Eurasian continent (Gourou, 1966) is an extension of the former. An extension of the latter is that, in the “agricultural involution” of Java, population pressure, abnormally increased by population growth and exploitation, caused such intensification that marginal labor productivity became negligible (Geertz, 1963). This question of causality in the changes in population and food supply is an immediate problem for today’s tropical agriculture. 8 Probably, in fact, the relation between population and agriculture is not causal but an interactive one in which both change accordingly. Another frequently cited example of the interaction between human and ecological elements is the problem of environmental change caused by agriculture and the readaptation, or failure thereof, of agriculture to the changed environment. The influence of agriculture on the environment may, for example, be the expansion of arable land, overgrazing, or environmental destruction and pollution by machinery, fertilizers, and pesticides. It is clear from these examples that the problem of interaction is important to an understanding of the circumstances of not only presentday tropical agriculture but also agriculture in general. A paradigm is needed, therefore, that can handle this adequately. Human ecology studies the relations, including the interactions, between human and ecological elements. In the paradigm proposed by Rambo (1982) for the study of these interactions, individual elements, human or ecological, are not structural elements within the same system; each group of elements forms its own system, and the two systems interact (Rambo, 1981). As we have seen, in both the ecosystem and the adaptation models, either human or natural elements are not treated systematically. In this regard, the proposed two-systems model may well be an advance. Human and ecological elements interact in various situations, of which agriculture is one. Thus, in the two-systems model, agriculture may be understood as one of the interfaces between the two systems. This characterization of agriculture, which, after all, derives from a

10

INTRODUCTION

paradigm for human ecology, will probably not make a student of agricultural science happy. But the question is whether the paradigm will be effective for agroecology. To give my conclusion first, I reject this paradigm. If it were to be adopted, it would be necessary to posit the existence of a system for each group of elements without any prior interaction with the other group of elements.9 Generally, whatever paradigm is used, agriculture is regarded as a part of human activity when it is approached from the social sciences and as the performance of crops when approached from the agricultural sciences. Both these contrasting approaches are in complete agreement that agriculture essentially involves both humanity and nature, and both appear to hold firm to the proposition that they must be treated separately. But why must they be so treated? Is it theoretically inevitable for there to be a dichotomy between humanity and nature when we are dealing with agriculture? Is the dichotomy really effective when the aim is to reach a comprehensive understanding of agriculture? Does this dichotomy arise simply because of the way in which established academic disciplines are arranged? First, let us set aside our identities as either social or natural scientists, abandoning the a priori view of agriculture either as a kind of human activity or as crop performance. Instead, let us see it as it is, that is, as a system in which both human and natural elements are inseparably involved. Second, let us differentiate between the extrasystemic elements that condition the system and the intrasystemic elements that interact within it, be they human or natural. The extrasystemic elements condition the system’s functioning through its adaptation to them as a system, not through the adaptation of individual intrasystemic elements. When extrasystemic elements change, the system readapts, again as a system. Such effects of the extrasystemic elements could successfully be described by use of adaptation models. But, even without changes in the extrasystemic elements, the system will change because intrasystemic elements, such as population or soil fertility, also change over time. This aspect could be dealt with by an ecosystem model if we strictly eliminated the extrasystemic elements. But the changes in an agricultural system as we observe them are the synthesis of changes in extra- and intrasystemic elements. By differentiating between extra- and intrasystemic elements and considering as intrasystemic only those that are really interactive, in the strict sense of the word, we can reduce the number of elements in a system to be studied to a practical level. This allows nondiscrimination of human and natural elements while not being too ambitious.

11

THE P U R P O S E OF THE S T U D Y

As with all models, the paradigm of agroecology must undergo a process of validation. One purpose of this book is to validate the proposed paradigm through a study of the agriculture of a village in Northeast Thailand. This includes an implicit desire to demonstrate the general importance of a comprehensive study of actual agriculture, and one example of the methodology may encourage further research of this kind. This desire is reinforced by the fact that nowhere within the current system of agricultural science is there a forum in which this kind of study can be assessed.

3. The DD Study as an Area Study Each of the participating researchers can locate the DD village study differently within the area study of Southeast Asia. Here is my own view.

The Image of Asia Asia, particularly humid Asia, is well known for its high population density, which is considered to be a basic cause of Asia’s food problems. It is believed that Asia’s population is too great for its agricultural land and that no more potentially arable land remains. But is this image accurate? Let us examine potential agricultural land assessed by the President’s Science Advisory Committee in 1967 (see table 1-1). It seems clear from the table that the area of cultivated land per head of population in Asia

Table LI Land to Population Ratios, by Continent LAND AREA (100 million ha)

CONTINENT

Africa Asia Oceania Europe North America South America USSR Total

POPULATION IN 1965 (million)

310 1855 14 445 255 197 234 3310

TOTAL LAND

POTENTIALLY ARABLE LAND

EXISTING iARABLE LAND

ARABLE LAND PER PERSON (ha)

3.01 2.73 0.82 0.48 2.10 1.75 2.23 13.13

0.73 0.63 0.15 0.17 0.46 0.68 0.36 3.18

0.16 0.52 0.02 0.15 0.24 0.08 0.23 1.39

0.51 0.28 1.15 0.34 0.93 0.39 0.97 0.42

SOURCE:President's Science Advisory Committee, 1967.

EXISTING ARABLE LAND/ POTENTIALLY ARABLE LAND (*)

22 83 11 88 51 11 64 44

12

INTRODUCTION

is small and potentially cultivable land limited. However, the table does not of itself demonstrate that this is a basic cause of food shortage in Asia. First, no such shortages occur in Europe, where, similarly, the area of cultivated land per head of population is small and the potentially cultivable land limited. Second, food shortages do actually occur in areas where the cultivated area per head is relatively large and a considerable amount of potentially cultivable land remains. It seems probable, therefore, that food shortage and the amount of potentially cultivable land are unrelated. B. W. Hodder (1980, 83-85) notes, The use of the term population pressure is generally valid only when the distress or poverty is seen to result directly from there being too many people in an area—too many in the sense that fewer people would result in an improvement in the standard of living. In fact, however, such a relationship can rarely, if ever, be demonstrated; and, in practice, it is to be doubted whether it exists anywhere. Furthermore, it is perhaps not too much to suggest that population pressure in the sense of there being too many people in an area for the available natural resources—whether land or any kind of natural resource—is a rare phenomenon in tropical underdeveloped lands. . . . On the other hand, there seem to be firm grounds for asserting that the rate of population growth is central to any study of tropical development: in its simplest terms, the chief problem of tropical development is how to increase production at a rate substantially higher than the rate of population growth.

This argument is persuasive, but, for the Japanese and many other Asians, it is difficult to accept. Let me try to argue against it. One reason that Europe has no food shortage is its low rate of population growth; another is that it imports large quantities of food and animal feed. On the other hand, where food problems exist in Africa and South America, they arise basically because expansion of cultivated land has been hindered for some reason. In Asia, the rate of population growth is high, and food production cannot keep up, basically because of the exhaustion of newly cultivable land. Thus, the imbalance between the rates of population growth and expansion of food production in Asia is, rather, the result of population pressure on land, a manifestation of Hodder’s “rare phenomenon.” Can this counterargument be proved? According to Food and Agriculture Organization (FAO) statistics for 1968-1984 (table 1-2), in Europe, the rate of population growth is low, and the arable area has decreased.10 In both Africa and South America, population growth is high. In Africa, the expansion of arable land does not match population growth, and the grave food problem that has

13

T H E P U R P O S E OF T H E S T U D Y

Table 1.2 Increase in Population and Arable Land Area by Continent, 1968-1984 POPULATION

Africa N. & C. America S. America Asia Europe Oceania USSR

ARABLE LAND AREA

1968 1984 (million)

INCREASE (X)

334 537 308 396 182 263 1,944 2,778 454 491 19 24 238 275

37.8 22.2 30.8 30.0 7.5 20.8 13.5

1968 1984 ( m i l l i on h a )

143 253 71 417 133 42 225

166 268 113 427 126 49 228

INCREASE (%)

13.9 5.6 37.2 2.3 -5.6 14.3 1.3

SOURCE: FAO Production Yearbook; see also note 11.

resulted is well known. In South America, on the other hand, arable land has expanded faster than the growth in population, and this is thought to be connected to the absence of a food problem in this region. By contrast, the population growth in Asia is as high as that in Africa and South America, but there has been almost no increase in cultivated land there. The FAO statistics do not show the area of potentially cultivable land directly, but, judged from a comparison of increases in population and cultivated land, the counterargument outlined above does seem to apply. This means that the image of Asia given at the beginning of this section— an overly large population, short of food and short of land —is in fact correct.

Sparsely Populated Southeast Asia All those who have visited the deltaic regions of mainland Southeast Asia must have received a strong impression of the wet rice fields that stretch to the horizon. The land area is vast, and the density of settlements is by no means high in comparison with Japan. National agricultural statistics show that the proportion of small farms of less than 1 hectare, like those in Japan, is very low. In insular Southeast Asia, the scenery resembles that of Japan. But most of the cultivated land there bears more than one crop each year, and, if this is reckoned as an increase in cultivated area, the cultivated area per household is by no means limited. The superficial, tourist’s image of an overpopulated, land-short Asia does not seem to apply to Southeast Asia. 11 That region invokes, rather,

14

INTRODUCTION

the image of the “prosperous South Seas” held by earlier generations. How do Southeast Asian area studies view this complete contrast? At the beginning of his recent book on the population and peoples of Southeast Asia, Tsubouchi (1986, 1) states, “In the history of the population of the world, Asia has always formed a center of population. However, within Asia, Southeast Asia has occupied a distinctive position through the relative sparsity of its population.” He also discusses the relative sparsity of the population of Southeast Asia, citing specific figures and referring to McEvedy and Jones (1979). Since the Indian subcontinent, mainland China, and Southeast Asia have similar areas, it is possible to compare their population densities by comparing their total populations. Tsubouchi (1986, 4) continues, “The rapid population increase in recent years has increased the relative size of Southeast Asia, but even so the populations of the Indian subcontinent and mainland China are more than twice that of Southeast Asia, and thus Southeast Asia remains relatively sparse in population. . . . At this time [1850] China supported a population 10 times that of Southeast Asia and 5.4 times that of the Indian subcontinent.” He himself notes the difficulty of making such comparisons without taking into consideration the distribution of arable land, but, provided that there is no marked difference between the three regions in the proportion of the total land area that is potentially cultivable, it cannot be denied that the population of Southeast Asia is relatively sparse. The distribution of potentially cultivable land in Southeast Asia is, unfortunately, difficult to assess, and no studies can be found that can help. The presence or absence of potentially cultivable land can be judged only indirectly, by observing whether cultivated land is expanded. One well-known example of the expansion of food-producing agricultural land in Southeast Asia is the development of paddy fields in the deltas of the mainland from the mid-nineteenth century. The fact that almost all today’s granary regions are the result of land development since this time indicates the sparsity of the population. Also, the rubber, sugarcane, and coffee plantations that flourished under colonial governments would have been impossible to establish without extra land in addition to that necessary for self-sufficiency in food. But what about recent years? Again using FAO statistics, let us compare the contributions to increased rice production made by increased yields and increased arable areas in various Asian countries for a 20year period from the 1960s (table 1-3). 12 As shown in the table, the contribution of areal expansion is, not surprisingly, almost zero in China, but it is considerable in other countries. Even in India, which is

15

THE P U R P O S E OF THE STUDY

Table 1.3

Changes in Population and Production, Area, and Yield of Rice in Rice-growing Countries in Asia, 1961-1965 to 1983-1985 INCREASE IN POPULATION

India Bangladesh Sri Lanka Nepal Myanmer Thailand Malaysia Indonesia Philippines Vietnam China Japan

W

PRODUCTION w

58.6 72.2 47.7 62.6 59.1 70.4 72.2 58.4 71.7 73.5 50.7 2.7

70.1 38.8 172.9 26.8 88.7 79.2 59.9 200.0 103.3 59.4 99.8 13.3

AREA w

16.5 15.8 66.2 24.2 -0.7 50.3 25.8 34.9 3.4 17.7 7.3 -29.4

CONTRIBUTION (%) TO INCREASED PRODUCTION OF INCREASE IN YIELD 3 w

46.7 16.7 66.7 0.0 93.8 17.6 28.2 116.7 92.3 35.0 89.3 60.5

AREA

YIELD

26.2 48.7 49.8 100.0 -0.7 74.0 47.8 23.0 3.6 33.6 7.5 -94.4

73.8 51.3 50.2 0.0 100.7 26.0 52.2 77.0 96.4 66.4 92.5 194.4

NOTE: a. Here, "yield" means production divided by land area. Therefore, unless the land areas have been doubled to account for double cropping, an increase in yield in this table means an increase in yield per unit area per year. SOURCE: FAO Production Yearbook.

regarded as being densely populated, at least one-quarter of the increase in production is due to an increase in area. In Southeast Asia— and probably in South Asia—it is notable that new agricultural land continues to be opened up and to contribute appreciably to the increase in production. Thus, at least as judged from the increase in area of cultivated land, Southeast Asia has always had a wealth of potentially arable land, land that, even in recent years, has not run out. Southeast Asia is a society that has always had a frontier. In conclusion, the image of Asia as overpopulated and short of land may apply to China and India, but it does not apply to Southeast Asia. Because China and India are so huge, their images and statistics overshadow Southeast Asia, making it difficult to view the region clearly. In his 1986 book, Tsubo.uchi focuses on the relation between the sparsity of Southeast Asia’s population and territorial expansion, cities, society, and government; in the present work, which is intended as, among other things, an area study, I examine what a sparse population and the existence of a frontier for land development mean for agriculture and agriculturists, basing my examination on the example of DD village.

16

INTRODUCTION

4. Note on the Text and Terminology There is no universally accepted method of romanizing the Thai language. For provinces (changwat) and districts (amphoe), I have followed the method used in the Government Gazette (Ratchakitchanubeksa, vol. 84, no. 56 [1967]), published by the Office of the Prime Minister, and have attempted to follow this for other cases, not only place names. The only Thai unit of measurement to appear repeatedly in this book is the unit of area, the rai. One rai is a square with 40-meter sides, or 1,600 square meters, 0.16 hectare. There are 6.25 rai in 1 hectare. Other measurements are explained when necessary. The unit of currency is the baht; throughout the period of the study, 1981-1983, the exchange rate was almost always 1 baht to 10 Japanese yen. Thailand is divided into the following administrative areas, listed in decreasing order of size: changwat, amphoe, tambon, and muban. Urbanized areas are known as thesaban, which is translated as “city.” 13

1 Northeast Thailand

The territory of Thailand is said to be shaped like the head of an elephant facing westward. The country is usually divided into four regions, the North, the Northeast, Central Thailand, and the South, 1 with the Northeast corresponding to the elephant’s ear (see fig. 1-1). This region is referred to popularly as Isan, a Pali word that means “northeast.” Let us first look at the main features of the region at present.

1. The Agricultural Landscape Bangkok is located at the mouth of the elephant silhouette. The main highway north from Bangkok passes through a large paddy zone intersected by straight canals. Peasants’ houses line the canals in the pattern familiar from the air above the Bangkok airport. The highway runs for more than 100 kilometers before reaching the eastern edge of the Central Plain, where a highway branches off to the east. This is the Mittaphap (Friendship) Highway, the main route linking Central Thailand and the Northeast. A little way from its branching point the highway begins to climb and continues to rise and fall for about 50 kilometers. The scenery is one of limestone cliffs with neatly plowed upland fields extending almost up to them, completely different from the dead-flat paddy land of the Central Plain. The soil is dark shades of red and black. There are fields of maize, sorghum, and cotton, mango groves, and grazing for livestock. The region reminds one of the agricultural land of Hokkaido, North America, and Europe. The road crosses the low mountains that separate the Chao Phraya River system from the Khorat Plateau, which makes up most of the Northeast. After passing along the foothills of the last mountain, which is shaped like a hog’s back with a level ridge, the road follows a final downward slope to enter the Khorat Plateau. Here the scenery changes once more. Neither is it completely flat, nor are there notable variations

17

North

Northeast

j

0

100

Central

200km

South

(P

Figure 1-1. The four regions of Thailand.

NORTHEAST T H A I L A N D

19

in height; instead, there is a series of undulations. In the lower parts, there is paddy land and, in the higher parts, upland for dry-field crops. The paddy land is not like that of the Central Plain, however, and the upland fields are unlike those previously seen. Located on slopes are many separate, small paddy plots surrounded by strong bunds. There seem to be no watercourses. It is not unusual to see uncultivated paddy land even in the rainy season. Although this is a paddy area, it is dotted with trees (Grandstaff et al., 1986). There are termite mounds with trees growing on top of them. There are huts with water buffalo resting nearby. Almost all the crops grown in the upland are cassava (manihot). The soil is pale in color. Here and there are groves of spiky bamboo and scrub. There are few streams,, and even these seem to flow only when it rains. And, of course, there are no canals. Overall, the impression is of dryness, quite unlike the general image of Asia as hot and humid. The impression is of the African savanna, where lions rest in the shade of the sparse trees. A “park-like landscape,” Pendleton’s (1962) description of the Khorat Plateau, suggests the, sparsity of vegetation. The buildings of the villages are huddled together, with a water tank (a pond built as a water supply) next to them. This landscape extends over the entire area of the elephant’s ear, across the large area from the point at which we entered it over the mountains from the Central Plain, northeast at an angle of about 90 degrees to the Mekong River. This is the Khorat Plateau. How this landscape differs from that of the other regions of Thailand can be seen from the following simple descriptions. Central Thailand is characterized by a flat topography. This is particularly true of the central part of the region, the Chao Phraya delta. There are marked differences in water conditions according to season: Takaya (1978) has described it as being “a sea of shallow water” for half the year and “a desert of clay” for the other half. It is characterized by an annual inundation that is not quite a flood, followed by a dried-out state after the water has receded. Wet rice is well suited to these conditions and is the only major crop grown in this area. Between the delta and the mountains that surround it are fans and terraces, where the scenery somewhat resembles that of the Khorat Plateau: rice growing is unstable because of water shortage, rain-fed paddy land with poor soils predominates, and termite mounds with trees are scattered throughout the paddy land. The North, which forms a single region for the purposes of administration and the gathering of statistics, comprises two parts in terms of its landscape. The northern part is a region of steep hills and basins with limited area. In the basins, the rice growing closely resembles that of

20

CHAPTER 1

Japan, an intensive cultivation dependent on run-of-the-river irrigation. If the coconut palms were pines, it could be a Japanese village scene. Double-cropping of rice is also common. The mountains are inhabited by hill tribes who engage in shifting cultivation. The southern part of the North is an extension of the Central Plain, which it adjoins. However, it is not as flat as the Central Plain and is full of small, sharp prominences formed by erosion and deposition by the rivers. Paddy land is still predominant, but the proportion of upland is greater than in the Central Plain. The proportion of naturally flooded low areas is small. The foothills of the surrounding mountains are marked by the development of fans and terraces with large areas of rain-fed land. The South is a world of such perennials as rubber, coconut palms, and fruit trees and of tin mining and fishing. Paddy land is found mainly in part of the east coast of the peninsula. The seasonal variation in rainfall affects the agriculture little since the absolute volume of rainfall is large. The forests are luxuriant tropical rain forests. Although the South is continuous with the mainland, this is no longer mainland scenery but that typical of the archipelago that stretches from there through Malaysia and Indonesia. It is evident that the natural conditions in the Khorat Plateau are the most severe in Thailand. What most Thai people associate with the Northeast, Isan, is a dusty, monotonous landscape with little greenery.

2. A Statistical View of the Northeast According to a 1980 census (NSO, n.d.), 15,690,000 people live in the Northeast, 35 percent of the national population of 44,820,000. The Northeast has an area of more than 170,000 square kilometers, 33.1 percent of the total national area; thus, this region accounts for about one-third of Thailand in terms of both population and land area. With an urban population of only 9.3 percent, the Northeast is evidently a region predominated by rural villages. 2 According to statistics for the crop year 1978-1979 (Office of Agricultural Economics, 1979), agricultural land in the region totaled 7,730,000 hectares, 45.4 percent of the region’s total area, and 72 percent of this was paddy land. In this year, 4,450,000 hectares of paddy land were cultivated, equivalent to 47.6 percent of the national area of paddy land. The Northeast’s share of the total production was only 34.5 percent, however, as the average paddy yield was a low 1.2 metric tons per hectare. Rice growing in the Northeast is characterized by low yields and instability. An analysis of annual variations in rice production by changwat for about 20 years to 1968 revealed that there were six changwat

NORTHEAST THAILAND

21

nationwide with unstable production represented by a coefficient of variation of over 30 percent, and five of these were in the Northeast. Of the total variation in production, 77 percent can be attributed to variations in planted area (Uchida et al., 1981). Thus, the changwat with large variations must have many paddy plots that are not planted every year. Conditions are evidentiy so harsh that the question is not whether the crop will grow well but whether it will grow at all. By the 1980s, such unstable conditions may have deteriorated; certainly, they have not improved, for, although the area of rain-fed land has continued to expand, there has been only a slight expansion of irrigated land. Similarly, according to agricultural statistics for 1978-1979, the most commonly cultivated crops in the Northeast, after rice, were cassava, maize, and kenaf. In all, they were grown on 1,300,000 hectares, half of which were planted with cassava. Cassava is the hugely predominant upland crop of the Khorat Plateau, while maize cultivation in the Northeast is largely limited to the southwestern part near the border with the Central Plain. Sugarcane and pulses are also grown, but neither occupies more than a few tens of thousands of hectares. The Northeast is home to 62 percent of Thailand’s water buffalo. The low proportion of the total number of water buffalo slaughtered each year, 1.7 percent (as opposed to 8.2 percent of cattle slaughtered), reflects the fact that water buffalo are kept as work animals. Formerly, the Northeast was known as a source of water buffalo for the commercial rice monoculture of the Central Plain, but, with the use of tractors and agricultural machinery now widespread, their importance has decreased. The continued concentration of water buffalo in the Northeast indicates the backwardness of mechanization in the region rather than their importance as a source of income for the peasants. The Northeast also has 41 percent of the cattle in Thailand. They are kept mainly for meat, and, according to our all-household survey of DD, which I shall discuss later, households on the average keep slighdy less than one animal. In fact, only a certain proportion of peasants keep cattle, and for these people cattle provide an important source of income. Let us now convert these agricultural statistics into figures for individual peasants or households, using the 1978-1979 figures and the 1980 population census quoted above. Since there are 2,110,000 farming households in the Northeast, the average area of agricultural land per household is 3.67 hectares, and the average area of paddy land is 2.63 hectares. The average farm household consists of 5.91 people. Per capita rice consumption is difficult to estimate, but, since rice forms the main part of each of the three daily meals in the villages, it would not be excessive to assume the former Japanese standard of 150 kilograms of

22

CHAPTER 1

white rice per person per year. On this basis, the average household will consume 887 kilograms of white rice and have only 517 kilograms as salable surplus. A similar statistical examination of the Central Plain, the main riceproducing area, reveals that, while the average area of paddy land per farm household is only a little larger than in the Northeast, the yield is almost twice as much and the surplus available for sale amounts to 2,250 kilograms. Even if the assumption of rice consumption is questionable, the difference between the Central Plain and the Northeast is all too clear. Despite being a purely farming region dominated by wet rice cultivation, the Northeast is not a true “rice-bowl area.” This characteristic of the region, which at first seems paradoxical, will be one of the main points of my subsequent discussion. As might be expected from what has been said, the Northeast is poor. Let us examine this poverty through two different sets of statistics: the Gross Regional and Provincial Product (NESBD, n.d.) and the results of the Socioeconomic Survey (NSO, 1979). The latter studied a sample of 12,189 households in 1975-1976. In table 1-1, the two are compared by regional indices, with 100 being the national average. The scope of the two surveys was defined differently for the region of the capital and the Central Plain, and no direct comparison can be made. 3 The other three regions were defined in the same way. Both surveys showed the Northeast to be the poorest region, although the scale of poverty differed considerably between the two. 4 Furthermore, the total per capita production in the Northeast shown by the index in the upper part of the table is, in monetary terms, 6,123 baht, and per capita income is 3,038 baht (5,158 baht adjusted to 1981 prices).5 It is almost incredible that this important region, one-third of the country in terms of population and land, should be so different. Seen in this light alone, it is natural that the development of the Northeast is of the highest priority for Thai domestic policy. Table 1.1

Gross Regional Production (GRP) and Income (100 for national average)

Per capita GRP (1981) Per capita income (1975-1976)

NATION

METROPOLITAN AREA

CENTRAL

NORTHEAST

NORTH

SOUTH

100

277

120-192

37

68

84

100

173

122

72

86

97

SOURCES:Thailand, NESDB, n.d.; Thailand, NSO, 1979.

23

NORTHEAST THAILAND

3. Nature and Agriculture In the previous section, we saw that, although it is a purely agricultural region where rice growing predominates, the Northeast is by no means a “rice bowl.” I have already indicated the relation this has with the landscape of the Khorat Plateau. Let us examine this question in terms of the physical conditions of the Khorat Plateau as a place to grow rice (KKU-Ford Cropping Systems Project, 1980). The Asian rice zone is thought to have been established through the combination of rice-growing techniques, which are cultural elements in the wide sense, and natural conditions suitable for rice growing. These natural conditions are usually cited as a hot, humid, monsoon climate. However, a careful examination of the spatial distribution of the Asian rice zone in comparison with that of dry-field agriculture and a consideration of the unique hydrology of paddy farming reveal the importance of topographical conditions as well for the establishment of rice growing. The geographic location of the Asian rice zone is explained by the overlapping of a hot, humid climate with a landform in which mountainous terrain of Alpine orogeny predominates (Fukui, 1987). It is no coincidence that the Asian rice zone is located in a region where a hot, humid climate overlaps with an Alpine orogenic belt. Alluvial plains formed between the mountains have large catchment areas, and, if the mountain runoff can be used, those plains will receive more water than falls on them directly as rain. This advantage is exploited by paddy farming, which is characterized by the use of rain that has fallen in a place other than the place of cultivation, albeit in the same basin. The degree to which artificial means are used to exploit the inflowing water forms a continuum from complete water control to almost completely rain-fed conditions. Thus, the distinction between irrigated and nonirrigated paddy land can be only a matter of convenience. Although making up part of the Asian rice zone, plateaus and the terraces at the margins of the large plains tend to have limited catchment areas and, thus, limited absolute volumes of water. In these areas, the problems that must be faced predate the improvement of water control. That is, rice growing is highly dependent on direct rainfall. Such is the case in the Khorat Plateau. Figure 1-2 clearly shows the special nature of the Khorat Plateau as a rice-growing area. In the neighboring Chao Phraya basin and around Tonle Sap in Cambodia, flat alluvial plains less than 100 meters above sea level are enclosed by mountains more than 200 meters high, with only narrow belts of land of intermediate elevation along the skirts of the mountains. By contrast, most of the Khorat Plateau lies in this range of intermediate elevation, and the surrounding mountains are of

24

CHAPTER 1

E Elevation (meters) > 200

W

/ & RE

MS fi *

AY' BK


2

1

1 11 1

2

1 31 3 3 3

'2 2

5

2

2I

x 2y yx S xs

3

z_siw 3

3

3

3W 2

7

rp 3

Huai San

7

3

2

fl

7ft

7 7 7 7 1 7 1 Z 1 1 2 1

2 2

.!

’2' ‘

°6

Nong kae

/ WB Nong O

4

8

u

i 8

Figure 5-6. Spatial distribution of the fertility classes. Source: Miyagawa et al., 1985.

2

1

163

THE ENVIRONMENT AND RICE TECHNOLOGY

Paddy yield (g/nr)

400

300

200

100

Soil fertility class 1

2

3

4

5

6

8

Number of plots (11) (28) (14) (13) (8) (8) (8) Figure 5-7. Relation between paddy yield and fertility class under presumably slight water stress (95 percent confidence intervals). Source: Hattori and Matsufuji, in Fukui et al., 1985, chap. 8(2).

varieties and cultivation techniques currently in use in DD, variations in paddy yield in the range from less than 2 tons to more than 3 tons per hectare can be explained in terms of the natural soil fertility. It is also possible to find direct correlations between the analytic values of the topsoil and yield. By testing various combinations of ana-

164

CHAPTER 5

lytic values, the following multiple regression equation was found to express the total dry weight of the rice plants: Total dry weight = 490.6 x log(NH3 — N) + 149.9 x log(exchangeable K) + 12.4, ? = 0.392. The following regression equation was found relating the paddy yield with total dry weight: Paddy yield = 0.309 X total dry weight + 55.6, ? = 0.874. These equations and the analytic values for the 247 plots allow prediction of potential yields in the sample plots in the absence of water stress. The yields thus predicted are divided into five levels, and their spatial distributions are shown in figure 5-8.

Layout of Farmland Figure 5-9 shows the layout of the approximately 8,000 paddy plots in the area, which occupy nong surrounded by higher land. In the hill region, paddy land is located in the incised valleys and depressions formed by corrosion. These depressions are sometimes called nong, sometimes thung (meadow). Farm roads called thang khwei (water buffalo tracks) radiate from DD to the farthest of the village’s paddy land. There are no lateral connections between them since the areas operated by individual households are not so widely scattered as to require such connections. The primary purpose of these roads is for transporting threshed paddy from the fields to the village; thus, they are wide enough for an oxcart— although today pickup trucks are used —and run across land that is dry during the harvest season, which means that they go around the edges of the nong and cross the Huai San at several places by way of barrage bridges. The roads are also used during the rice-growing season to herd domestic animals from the village to their grazing land, and thorny hedges are planted along their sides to prevent the animals from straying into the paddy land. During the rainy season, wire is strung across any gaps in the hedges, but, once harvesting is completed, the animals are released into the nong. In each nong, paddy plots are larger in the center and become smaller toward the edge, reflecting differences in gradient. The flat land at the bottom of the nong means that large plots can be made without involving

165

THE E N V I R O N M E N T AND RICE T E C H N O L O G Y

Chi R.

Nong Do,

4 2 3

2

2 3 2

3 3

3 3

Z2 3 2

32 3

z

3

3 3 2 2

3 3

3'

3

2 '

4

4

3

)s

4

47

3

rA

3 3 3 . 3

3

3

3

3 3

44

3 z3 3 3

3

4 2

2

5

44 \ \

43 44

1

DN I f

Z

5 2 3 432 3 32

3

2

3

2

3 3 2 3 2 3 3 4

\ 3 I 33

3 Huai San

Z5 4 y

Nong Kae

Potential yields (t/ha)

3

2 1

2

\A\ 4> 4 w \

2

2 1

—< A '22 1

2:1.5-2.0 3:2.0-2.5

32

\ 2

4:2.5-3.0 5:3.0-

1

1

Average: 2.25

Figure 5-8. Distribution of potential yields estimated from soil fertility. Source: Hattori and Matsufuji, in Fukui et al., 1985, chap. 8(2).

much earthwork, while, on the slopes, a series of narrow plots must be constructed along the contours to limit the earthwork required. Plot size is not determined solely by gradient, however; bunds also indicate boundaries of ownership and management. Examination of figure 5-9 reveals many long, almost straight bunds climbing the slopes of the nong, either radiating from the center to the edge or cutting

Figure 5-9. Paddy plot map of the DD area. Source: Kaida et al., in Fukui et al., 1983, chap. 2.

THE ENVIRONMENT AND RICE TECHNOLOGY

167

across. Such bunds mark the boundaries of ownership and management units. Figure 5-10 shows part of the area on a larger scale, with ownership boundaries marked. Bunds are built at the expense of land that could otherwise be planted. In 1983, we made an intensive study of Nong Simban, the nong nearest the village settlement. In this nong, bunds built to mark boundaries accounted for 1.4 percent of the area, while those built for topographical reasons accounted for 6.8 percent.6 Figure 5-11 shows a histogram of plot size in this nong. Small plots of 1-4 ares were the most common in terms of numbers of plots. In terms of plot area, however, there were three peaks of plot size: 3-4 ares, 1020 ares, and over 50 ares. These correspond almost exactly to high, middle, and low paddy fields, respectively. The early pioneers in the DD area are said to have reclaimed the nong one by one, working as families or groups of families from the same place. The reclamation proceeded from the center of the nong toward the high land at its periphery, and, accordingly, each family came to own a strip of land running from the center to the periphery. Subsequent division of land has proceeded in the same direction, with the result that households continue to own and farm such strips of land and little scattering of holdings has taken place. About 70 percent of households operate land in only one location, and the maximum dispersal is three locations. 7 On the subject of the layout of land parcels, the process by which paddy land was reclaimed is suggestive. As I have stated, reclamation began at the bottoms of the nong, with the middle and high fields being opened in a relatively short time from as late as the 1940s. Until this time, the middle and high fields were woodland and grazing areas of little economic significance that were attached to the low fields. Even with the reclamation of the middle and high fields as paddy land, their attached nature persists. The labor productivity of these fields is so low that a unit consisting of these alone would be economically unviable: only in combination with low fields do they assume economic significance. This will be discussed quantitatively in the next chapter.

Moisture Regime of Paddy Land All DD’s paddy land is rain fed, and the moisture regime is determined primarily by rainfall. Even so, conditions of individual plots vary because rainwater is distributed unequally by such natural features as topography and soil and by certain human manipulations. The quantitative link between rainfall and the moisture regime of paddy land will be examined later with a simulation model. Here, I make an initial

50

100 m

B Plot boundaries (bunds) Ownership boundaries

0

Woods

Scrub, wasteland

Trees and hut

Pond

Figure 5-10. Typical ownership boundaries of paddy plots in a nong. Source: Kaida et al., 1985.

169

THE E N V I R O N M E N T AND RICE T E C H N O L O G Y

(%) 5040-

Proportion of number of plots 30-

20 -

10-

4=1

o 50

40-

Proportion of total plot area

30-

20-

10-

3

4

9

10

15

20

25

30

35

40

45

50

Plot area (a) Figure 5-11. Size distribution of plots in Nong Simban. Source: Kohno, 1985.

qualitative study of some factors that affect the movement of the water after it has fallen as rain. A nong is a depressional area surrounded by higher ground and can, therefore, be regarded as a small watershed. The water balance in a nong has been measured for the case of Nong Simban, which consists of 39.6 hectares of paddy land and 6.7 hectares of other fields (Kohno and Kaida, in Fukui et al., 1985, chap. 6). A flow meter was installed in each of the two drainage channels (rabai nam) joining the bottom of the nong to the Huai San. The total outflow from the nong between 27 July and the end of December 1983 was estimated at only 2.1 percent, with 97.9 percent of the rainfall being stored.8 The word nong means not only a depression with paddy land but also the pond or marsh at its lowest point. Interviews with farmers who

170

CHAPTER 5

manage the drainage channels indicate that these ponds or marshes were once quite large. 9 Probably, the reclamation of paddy land began with the drainage of these. The bottom lands that were difficult to drain may have been left unplanted until later, when the paddy area was expanded by improvement or construction of drainage channels.10 Because a nong constitutes a small watershed, it can be taken as a unit of water balance. This balance can be found from outflow through the drainage channels, evapotranspiration, deep percolation (water percolating to deep strata and not used again in the nong), and rainfall. However, the water balance of the nong tells little about the actual water regimes in the paddy plots because water is unevenly distributed within the nong. Water conditions in approximately 6,000 individual paddy plots were inspected at 2-week intervals throughout the rice-growing season of 1981. On the basis of the results, paddy land was classified into four grades (Kaida et al., 1985). Grade 1 plots, which had good hydrological conditions throughout the growing season—even in this year, which tended toward drought—corresponded to the low fields. Grade 2 plots, which suffered slight water stress at the early reproductive stage, were distributed in the middle fields. Grade 3 plots, which suffered moderate to severe water stress, were located predominantly in high fields on slopes. Grade 4 plots, where almost no harvest was possible, were high fields on ridges and natural levees. Plots at higher elevations than the grade 4 plots were not planted this year or, if planted, yielded no harvest. The following is a model that attempts to explain spatial and temporal variations in moisture conditions in terms of these plot-specific properties (Kaida et al., 1985). The plot-specific properties that determine moisture conditions are those governing the loss or gain of water. The former include percolation from the plot and evapotranspiration, the latter percolation into the plot through the bunds from higher plots. If these can be expressed by a single variable, it is possible to express the temporal change in moisture status of a paddy plot by the following expression11 : H t = H t _, + (R irt x K) - D( , where H t is moisture status on day i, H;-, is moisture status on the previous day, Ri-t is the previous day’s rainfall, K is the effective rainfall ratio, and Di is the volume of water movement (either D, or Z)2). The parameters other than Z)2 were determined on the basis of observations and measurements and several trial calculations: K = 1; D, = 3 millimeters/day; H mm = —100 millimeters; H tf = 100 millimeters; Krg =

171

THE ENVIRONMENT AND RICE TECHNOLOGY

10 millimeters/day; and zlp = the fifth day from the start of the inundation, after 15 July. By substituting these parameter values, the measured rainfall, and arbitrary values of Z>2 into the equation, it is possible to calculate temporal patterns of moisture status. These are then compared with the observed moisture status, and the D2 value giving the closest fit is taken as the D2 value of the plot in question. In 1983, moisture status was again surveyed in 1,335 plots, and D2 values were determined for each plot. Figure 5-12 shows examples for two plots with widely differing Z)2 values of the observed moisture status and that calculated using these Z>2 values. In general, the error between observed and calculated values was 2-5 millimeters per day, which is satisfactory. Figure 5-13 shows the effect of Z>2 on the period of standing water. Continuous inundation could be obtained in plots with a D2 value of 5 millimeters per day or less but not in those with a higher value. Figure 5-14 shows the spatial distribution of D2 values in Nong Simban. Overall, these correspond with the topography, although not in fine detail. In (cm)

—

Estimated

•

Observed

Middle fields

• (

High fields

\ A

A- _____

•-

83

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec 8 4 Jan

Figure 5-12. Comparisons of observed water depth in paddy plots with values estimated by use of parameter D2. Source: Kohno and Kaida, in Fukui et al., 1985, chap. 6(3).

172

CHAPTER 5

Jun Parameter!

Jul I

Aug I

Sep I

Oct I

Nov I

Dec 1

T

D2 3 4 5

I | B B B 0

oo SSSUffl I B M 0 OB a i 00 EZJ B 00

mi no SO HO HO HO

E w l Period with standing water

Figure 5-13. Parameter Z>2 and patterns of seasonal variation in water conditions in paddy fields. Source: Kaida et al., 1985.

some topographical units, plots showed a relatively narrow range of Z)2 values, but, in others, the range was wide. Thus, Z>2 values, that is, water movement, are correlated with, but not determined solely by, topography. Nevertheless, it is possible to propose typical Z)2 values for high, middle, and low fields. Figure 5-15 was prepared by substituting these values into the equation together with the rainfall figures for 4 years; it shows the temporal changes in moisture status, the estimated dates of transplanting, and the harvesting periods for each year in each type of paddy field. Also shown is the degree of drought damage in each year as reported to us. The figure indicates not only that annual variations in the cropping calendar can be accounted for but also that rainfall and production are linked, in a roundabout way, through the intermediate term of moisture status of paddy plots. That is, it indicates the possibility of estimating production from rainfall. We are still, however, a long way from being able to simulate production, as this approach has various defects.12 Given these insights, however, what kind of simulation model can be constructed? Before addressing this problem, we should look in a little more detail at the agronomy of rice, including cultivation methods, varieties, and productivity.

THE E N V I R O N M E N T AND RICE T E C H N O L O G Y

173

Figure 5-14. Spatial distribution of D2 parameters in Nong Simban. Source: Kohno and Kaida, in Fukui et al., 1985, chap. 6(3).

2. Current Rice Growing Present-day rice growing in DD involves both upland and lowland rice, of which the latter is predominant.13 As DD is located in the glutinous

174

CHAPTER

Year

Field type’

1*

Drought damage extent2

5

Changes in moisture conditions Harvest '

Jul

Oct , Nov .

' A W . .See

H 1979

M L H

1981

M

O

L

O

H 1982

t

M

■

.1

L H 1983

M L

1

O

o o

KWBm

V

I ....

....

Moisture stress

1 Standing water No standing water

I |

\7

Transplanting date

Figure 5-15. Changes in standing water and drought damage. (1) H: High fields, M: Middle fields, L: Low fields (2) O: No damage, A: moderate damage, X: severe damage (Yield = 0) Source: Kaida et al., 1985.

rice zone (Watabe, 1967; see also chap. 2, sec. 1, above), the majority of the lowland rice is glutinous. In 1981, glutinous varieties accounted for 89 percent of the area planted to rice. 14 These can be broadly grouped into three: early, intermediate, and late maturing. The villagers call these khao do, khao klang, and khao nyai and distinguish clearly between them when selecting varieties. Apart from the upland varieties, all rice is transplanted. After enough rainwater has accumulated in a paddy plot, water buffalo are used for plowing and puddling. The peak season for transplanting varies from year to year; it fell in mid- and late July in 1981 and early and midAugust in 1983. After transplanting, the crop is hardly tended. Very few weeds grow, and it is rare to see anyone weeding. The time of heading is determined by the rice variety: early maturing varieties head in

THE E N V I R O N M E N T AND RICE T E C H N O L O G Y

175

late September and early October, intermediate and nonglutinous varieties in mid- to late October, and late varieties in early November. All varieties are harvested about 1 month after heading. The rice is reaped with sickles to a length of about 90 centimeters, convenient for bundling and threshing. Threshing is performed by striking the bundles against a threshing floor, which is prepared each year in a higher paddy field in a nong or on grassland by stripping off the sod and sealing it with water buffalo dung. The threshed paddy is stored in a stilted granary in the house compound. This, in outline, is the rice cultivation in DD at the time of the survey. Its various aspects are described in detail below and the process of grain formation analyzed.

Varieties Lowland rice varieties can be broadly divided into glutinous and nonglutinous types. The former is the daily staple; the latter is used for festivals and guests. Of the 376 hectares of paddy land surveyed in 1983, 91.2 percent was planted with lowland rice, of which 80.7 percent was glutinous rice and only 10.5 percent nonglutinous. Lowland varieties are, as we have seen, also further divided into early, intermediate, and late maturing, in which heading is progressively later by intervals of about 20 days. The majority of nonglutinous varieties head at the same time as the intermediate glutinous, but some are very late maturing and head 10-20 days after late glutinous. Of the glutinous varieties planted in 1983, the majority were intermediate and late maturing, accounting for, respectively, 40.6 and 45.3 percent of the total planted area, as opposed to only 4.3 percent for the early varieties. Glutinous varieties consisted of six early, twenty-nine intermediate, and five late maturing. Nonglutinous varieties totaled seven, of which two were very late maturing. Of this large number of intermediate varieties, most were indigenous, but some high-yielding improved varieties such as RD6 could also be found. 15 Some of the lowland varieties can also be planted in upland fields. One of these is an early glutinous variety, another an intermediate nonglutinous variety, both of which produce small grains with a thousand-grain weight of around 20 grams. In places where paddy land adjoins upland, which is also bunded, upland rice may be sown directly or lowland rice transplanted, depending on the year’s rainfall. According to the accounts of the older villagers, 40-50 years ago there were five early, six intermediate, and six late maturing glutinous varieties, one nonglutinous variety, and no upland rice. 16 Mizuno reported that the main varieties of rice in DD in the early 1960s were three early, nine intermediate, and one late maturing glutinous type

176

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(Mizuno, 1981, 46-47). He noted that intermediate varieties were traditionally predominant, as they are today. However, the names of individual varieties common 20 years ago, let alone 40-50 years ago, are no longer heard. Successive floods have carried away crops, and seeds have been lost. This also happened in the recent major floods of 1978 and 1980. 17 Each time, villagers were supplied with various varieties by relatives living inside or outside the changwat. Thus, although some of the varieties used in DD are mostly “indigenous,” they are indigenous not necessarily to DD but to the Northeast generally. These varieties have been introduced incidentally by individual villagers, and their history in DD is short. There is, therefore, a certain confusion about names. Some care is needed to find a correspondence between the variety name used by the villagers and the inherent characteristics of the variety. In fact, the same variety with different names and different varieties with the same name have been noted in some numbers. For this reason, the varieties are discussed in the following account in terms of groups, classified according to maturing time.

Cultivation Methods The growth and yield, and also the cropping calendar, of rain-fed rice are at the mercy of the year’s rainfall. Figure 5-16 shows the daily rainfall and the areas seeded, plowed, and transplanted at Nong Simban during 1983. The patterns of these operations follow that of rainfall, coming in short bursts 1 or 2 days after substantial falls of some 10s of millimeters. Rainfall means a peak of activity, and, in the intervals between rainfalls, no activity is possible. In rain-fed rice cultivation, standby time is long and actual labor time short. I shall examine this again in discussing labor productivity in the next chapter. Rice growing usually begins in May or June once sufficient rain has fallen to allow plowing of the plots to be used as nurseries. Paddy for use as seed, which has been stored in the same granaries as but separately from that for consumption, is taken out, placed in a water-filled jar, and sorted. The soaked rice is placed in a bamboo basket to germinate, the basket being sealed with water buffalo dung. Every year, each cultivator prepares his nursery in the same high, well-drained, small plot (around 400 square meters) located near his hut. Of the 5,000 paddy plots surveyed in 1983, 701 plots, accounting for 8.2 percent of the total planted area, were used as nurseries. After the nurseries have been seeded, the main fields are plowed in succession after each substantial rainfall. Then, preferably between 4 and 7 weeks after sowing, the main fields are again plowed and puddled following a substantial rainfall, and the seedlings are transplanted.

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THE ENVIRONMENT AND RICE TECHNOLOGY

Daily area 2,400 r

rrf

Plowing 2,000

Transplanting

,1 ' ’ 4 II

1 1' ' '1

•M

1,000

Nersery j> seeding ;lr

1

‘v
» t

160 Bn 140

Daily rainfall

80 60 40 20

11

21

1

11

21

Jun

Jun

Jul

Jul

Jul

1 Aug

11

21

19

Aug

Aug

Sep

Sep

Figure 5-16. Daily rainfall and progress of seeding, plowing, and transplanting. Source: Miyagawaet al., 1985.

Seedlings are pulled up rather roughly, which may cause severe root damage, as the nursery soils are often water-deficient and hard-packed. They are then knocked against the foot to remove soil adhering to the roots and bundled together with bamboo rope. Long plants are cut to size; then the bundles are carried to the main fields on the ends of a carrying pole. Seedlings are transplanted at random intervals, with the planter moving backward. Because DD’s paddy soils are rich in sand, which settles and compacts after puddling, making transplanting difficult, this operation must be done on the same day as or the day after the second plowing and puddling. This factor increased the labor peak even further. The average water depth at the time of transplanting is about

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CHAPTER 5

95 millimeters. In 1981 and 1983, the transplanting period ran from late June to mid-September, with the main peak coming earlier in 1981 and about 20 days later in 1983. If there is no suitable rainfall, transplanting may be further delayed and result in a decrease in the planted area. In both 1981 and 1983, cutting surveys were conducted at harvest time. The method employed will be described later. The planting densities found by these surveys were 11.9 hills per square meter in 1981 and 12.4 in 1983, in which year an average hill consisted of 3.4 plants. The low fields tended to be slightly less densely planted (about one hill less per square meter than the average). When seedling growth is poor, hills tend to contain more plants; when seedlings are tall, they are cut down to about 30 centimeters before transplanting. When a farmer has insufficient seedlings, it is common for a neighbor to help him. Although a relation can be found between transplanting time and variety, it is less clear-cut than that between heading time and variety, being complicated by the influence of topography on selection of varieties and the order of transplanting. Since, moreover, topography governs moisture conditions, the relation between transplanting time and variety depends on the annual variations in rainfall. Generally, however, late varieties tend to be transplanted first. The use of fertilizers or other chemicals was not observed in 1981. In Nong Simban in 1983, three people applied ammonium sulfate and four pesticides to their nurseries, while one applied fertilizer to his main fields. In the whole village in 1983, chemical fertilizers were applied to about 8.6 percent of the total paddy area: ammonium sulfate to just under half this and various composite fertilizers to the rest. Very little manure was used. Harvesting is performed about 1 month after heading, the timing of which is determined by the variety and does not vary greatly with the timing of transplanting. Figure 5-17 shows the relation between transplanting and heading times observed at Nong Simban in 1983. It reveals that almost all the varieties are photoperiod sensitive. If late rains delay transplanting, therefore, the growth period is shortened, resulting in lower yields. Coming in the dry season, harvesting is not affected by rainfall variability, as are nursery preparation, plowing, and transplanting. But drought at the primordial panicle formation stage delays heading, and severe drought or flooding will, of course, make harvesting unnecessary. The rice is cut to about 90 centimeters in length and placed either directly on the dry ground or, if this is still wet, on top of the cut stalks. It is then gathered and tied with bamboo cord into sheaves of six handfuls, which are carried to the threshing floor and piled around it. The

179

THE ENVIRONMENT AND RICE TECHNOLOGY

Heading date

Nov

oooo ®

8% o O O

4

A A*A

Oct

Sep

v Early glutinous A Intermediate glutinous O Late glutinous □ ■ Nonglutinous -------------- Jul -------------------------------Aug----------------------- Sep

Transplanting date Figure 5-17. Relation between dates of transplanting and heading, by variety group (1983, Nong Simban).

threshing floor is made at the same place every year by plastering the ground with buffalo dung. The thresher holds, one in each hand, the ends of two short sticks, to the other ends of which are tied the ends of a piece of cord. He wraps the cord around a sheaf, raises it above his head, and beats it against the threshing floor. Eight to ten blows are sufficient to remove the grain, which heaps up on the floor. Straw is removed from the heap with a bamboo pole, but the grain is not winnowed. The paddy is bagged and taken to a granary in the house compound. Inside the granary, the glutinous varieties are usually piled up together, while nonglutinous varieties and seed paddy are kept separately. The straw left on the threshing floor is bound and stored for animal feed. It is often seen in crooks of branches where the cattle cannot reach. Varieties, Cropping Calendar, and Topography The relation between variety groups and topography is clear. Table 5-5 shows the situation in 1983. The low fields in both the hill and the flood-

180

CHAPTER 5

Table 5.5

Topography and Varieties Selected, 1983 (in %) GLUTINOUS VARIETIES INTERMEDIATE

NONGLUTINOUS VARIETIES

NOT KNOWN OR NOT PLANTED

TOPOGRAPHIC UNIT

LATE

Hill region Low Middle High

75.2 17.3 7.6

7.8 45.6 52.2

0.0 1.7 0.8

2.9 11.0 19.8

14.1 24.4 19.6

Floodplain Low Middle (sloping) Middle (flat) High

84.1 8.7 11.6 8.9

12.9 59.6 55.9 44.0

0.1 4.7 9.8 8.0

2.1 13.7 16.6 19.0

0.8 13.3 6.1 20.1

Total area

39.7

37.1

3.9

10.5

8.8

EARLY

SOURCE: Miyagawa et al., 1985.

plain regions are almost all occupied by late maturing glutinous varieties, which are seldom grown elsewhere. Conversely, the early glutinous and nonglutinous varieties are grown in the middle and high fields, seldom in the low ones. Intermediate glutinous varieties are grown everywhere but in the low fields. Almost all varieties grown in DD are, as mentioned, photoperiod sensitive, and, therefore, they head on a fixed date, whatever the time of seeding and transplanting, and reach maturity 1 month after heading. On the other hand, there is also a clear relation between variety and topography, which means that heading and harvesting times are more or less fixed for any topographical unit. This is shown in figure 5-18, together with the time of transplanting. Although the latter varies considerably between the years, there is still a clear tendency for the late varieties in the low fields to be transplanted a little earlier than others. The choice of variety according to topography, which thereby fixes the dates of heading and harvesting, is related to the different seasonal patterns of water status in different topographical units. The predominant choice of early varieties in high fields may derive from the negative consideration that the risk of water stress in these fields in.the latter part of the rainy season is greater than in the low fields. Alternatively, a positive choice may be made to grow early varieties, which the ease of drainage of the. high fields allows.18 Once a variety is chosen, the times of its heading and harvest are predictable, but the time of transplanting is not always so. Because transplanting begins when there is enough water and water accumulates first

181

THE E N V I R O N M E N T AND RICE T E C H N O L O G Y

Landform unit Hill region Top

Jul 1

Aug

i 1 1 Tran: planting

Sep

Oct

1

1

1

Nov 1

Heading

iyoi< o1983

1

Dec

I

Harvest

Slope Bottom Floodplain

' “ J - - __

High Middle (flat)

Middle

—

*

(sloping) . z*

Low i

—

t

t

t

1

1

i

t

1

1

1 ..t

o*o

Average •*— Range of standard deviation

Figure 5-18. Relation between landform and cropping calendar. Source: Miyagawaetal., 1985.

in the low fields, where late maturing varieties predominate, it is true that the late varieties tend to be transplanted earlier than the others. But the relation between variety and transplanting time is not always clear since it seems to be influenced by the proportions of the different topographical types within a particular landholding and the annual variability of water conditions.19 It is clear from what has been said above that the diversity of rice growing within DD results primarily from its topography, which, through the mediacy of water conditions, governs the choice of variety and the cropping calendar. The topography of DD is characterized by the nong, which is shown schematically in figure 5-19, while the characteristics of the resulting typology of rice growing are summarized in table 5-6.

Growth and Yield The growth and yield of rice were investigated by three methods. The first method was the standing crop survey during the harvest season, in which yields were graded in 2,600 plots. 20 The second was the cutting survey, covering 200 plots. 21 The third method was the growth survey, in which growth was recorded in thirty plots at regular intervals

Holding with small proportion of low fields

Boundary between holdings Hut -

Holding with large proportion

Drainage channel —

of low fields

Fish pond

Oxcart track —

Low fields

middle'/llpland rice, cassava, grassland fields High fields

Figure 5-19. Schematic view of a nong. Source: Miyagawa et al., 1985.

Table 5.6 Typology and Land Conditions of Rice Cultivation LOW FIELD CULTIVATION

MIDDLE FIELD CULTIVATION

HIGH FIELD CULTIVATION

Soil fertility

Relatively high

Medium

Medium-low

Water conditions

No outflow/inflow

Inflow/outflow

No inflow/outflow

Varieties

Late glutinous

Intermediate glutinous, nonglutinous

Intermediate and early glutinous, nonglutinous

Nurseries

Rare

Common

Common

Planting density

Sparse

Medium

Dense

Transplanting

Early

Middle

Late

Heading/harvest

Late

Middle

Early

Plot size

Large

Small-medium

Medium-small

Percentage of area

40

20

40

SOURCE: Miyagawa et al., 1985.

183

THE ENVIRONMENT AND RICE TECHNOLOGY

throughout the growing season and yield measured by harvesting the whole plot. Yield grades estimated in the standing crop survey were correlated with absolute yields by use of the measured yields in the plots that were also subject to the cutting survey. 22 The results of the cutting survey are summarized in table 5-7. The average unhulled paddy yield was 182 grams per square meter in 1981, a year of drought damage, and 236 grams per square meter in 1983, a year of unprecedentedly good harvest. The latter is probably close to the highest yield that can be achieved in the absence of water stress with DD’s present levels of technology and investment. Although it is still lower than the yields achieved not only in Japan but also in the main rice-producing areas of Thailand, where water conditions are comparatively stable and fertilizer is in general use, it is not unreasonably low in view of the low soil fertility in DD and the fact that fertilizer is mostly used only for the nurseries. Rather, it demonstrates that, given an adequate water supply, rice farming has a high latent productivity. The agronomic study of crop performance in DD is favored by the exceptional rainfall of 1983, which allows that year’s growth and yield Table 5.7 Yields Assessed by Cutting Surveys (1981 and 1983) (in g/m 2) 1981 MEAN

Paddy weight Straw weight Total weight

182 249 431

1983

MAX

MIN

c.v.

563 913 1,475

33 50 91

44 56 49

MEAN

236 319 555

MAX

532 1,511 1,882

MIN

66 60 126

c.v. (X) 32 62 46

NOTE: C.V. means "coefficient of variation." SOURCE: Miyagawa et al., 1985.

Table 5.8 Yield Components According to Variety (1983) GLUTINOUS EARLY

Number in sample Stalk length (cm) Unhulled grain weight (g/m2 ) Number of panicles per plant Number of panicles (/m2 ) Number of spikelets per panicle Ripening (%) Thousand grain weight (g)

INTERMEDIATE

LATE

NONGLUTINOUS

39

81

41

13

101 212 6.1 76.6 93.0 73.7 36.2

117 241 5.6 70.1 110.5 75.1 37.3

126 238 5.6 65.3 123.0 70.9 36.7

102 273 8.6 105.8 99.0 83.6 29.6

SOURCE: Miyagawa et al., 1985 and Miyagawa and Kuroda in Fukui et td., 1985.

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CHAPTER 5

Maximum Transplanting tillering

Primodial panicle initiation

Heading

Harvest

Early glutinous Intermediate nonglutinous

Late glutinous 1 -I ----1-----'-----1----1----------1 -----1----1----1----'-----1-----1----------

Jul

Aug

Sep

Oct

Nov

Figure 5-20. Growth stages of rice, by variety (1983, Nong Simban). Source: Miyagawa and Kuroda, in Fukui et al., 1985, chap. 8(1).

to be taken as representative of crop performance in the absence of water stress. I examine this first, then assess the effects of drought on the basis of the 1981 study. Table 5-8 shows average values for yield components of the different variety groups on the basis of the 1983 cutting survey. The greatest contrast is found between the late maturing glutinous varieties and the nonglutinous ones. While the former are tall and have fewest panicles, most spikelets per panicle, and a high thousand-grain weight, the latter are short and have many panicles, few spikelets per panicle, and a low thousand-grain weight. The former represent the panicle-weight or heavy panicle type, the latter the panicle-number or many panicle type. The latter gave the higher yield in this year. Intermediate maturing glutinous varieties have slightly more panicles and slightly fewer spikelets per panicle than the late ones, while their yields were of the same order as late maturing ones. They can also be classified into the panicleweight type. The early glutinous varieties also have fewer panicles than the nonglutinous ones but lack the compensation of more spikelets per panicle. They thus had the lowest yields of all the variety groups. Regardless of growth period, the glutinous varieties all have a high thousand-grain weight. Figure 5-20 shows the growth stages of each variety group. In early maturing glutinous varieties, the maximum tillering and primordial panicle formation stages overlap, while, in other varieties, there is a vegetative lag phase between the two. In intermediate varieties, this lag phase is up to 10 days, while, in late maturing varieties, it is at least 1 month. Transplanting was rather late in this year (1983); when it is earlier, the lag phase is correspondingly longer. Correlation coefficients between yield components were examined. Grain weight was positively correlated with the spikelet number per

185

THE ENVIRONMENT AND RICE TECHNOLOGY

unit area (0.895, p = .001) and the dry weight (0.802, p — .001), but the number of spikelets per unit area was not correlated with percentage of maturity (0.069, NS). Thus, it is possible to discern a general tendency for good vegetative growth to result in a good yield. In that the average yield is less than 3 tons per hectare, this is quite predictable, even for indigenous strains. Figure 5-21 shows the relation between paddy weight and total dry weight on the basis of the growth survey at Nong Simban. Here, too, these figures are proportional, indicating that leaves and stems do not flourish at the expense of grain production. Thus, it seems that nutrient supply regulates both growth and yield. However, the same figure shows that paddy weight tends to account for a slightly lower proportion of the total weight in the late maturing varieties, which have a long vegetative lag phase. This suggests that, although the hereditary traits of these varieties do not limit yield at the present level of 2 tons per hectare, different varieties would be needed if higher yields were sought by use of fertilizer. Even though the situation is not quite a trade-off between number of spikelets and ripening, the question remains whether to secure a sufficient number of spikelets per unit area by having many small panicles Paddy weight (g/m 2) 600

Early glutinous

□ Nonglutinous

Intermediate glutinous O Late glutinous

A

□

400

o 200

0 400

800

1200

1600

Total dry weight (g/m2) Figure 5-21. Relation between paddy weight and total dry weight (above ground) (1983 growth survey, Nong Simban). Source: Miyagawa and Kuroda, in Fukui et al., 1985, chap. 8(1).

186

CHAPTER

5

or fewer large ones. At least in 1983, the intermediate nonglutinous varieties secured spikelets by the former means, while late and intermediate glutinous varieties did so by the latter. In general, varieties with shorter growth periods do this by the former means and those with longer periods by the latter. This is true at least for the nonglutinous and late maturing glutinous varieties grown in DD. To examine further the question of how better to secure spikelets, the correlation coefficients between yield components in each variety group were calculated (table 5-9). Except for early glutinous rice, relatively high yields in each group were obtained from both the many panicle and the large panicle types. 23 The correlation between the number of panicles and the number of spikelets per panicle, however, is, if anything, negative in all glutinous groups, in contrast to the positive correlation seen in the nonglutinous group; that is, in the glutinous varieties, whether early or late, the number of panicles and the number of spikelets per panicle tend to cancel each other out. This means that no great improvement in the number of spikelets per unit area can realistically be expected from improvements in cultivation methods such as applying fertilizer or reducing the lag phase by delaying transplanting, increasing planting density, or a combination of these. By contrast, not only do the nonglutinous varieties have a large number of spikelets per unit area under the present nutrient supply, but the above improvements in cultivation methods may also result in a further increase in spikelet numbers. The only varieties of the panicle-number type currently planted in DD are intermediate nonglutinous varieties. It may be difficult to replace the early varieties with these because of water conditions or the demand for rice in the lean period before harvest. Similarly, it may be difficult to replace the late varieties in the low fields because of problems of drainage during harvest and the ability to withstand submergence. However, if the difference between glutinous and nonglutinous is disTable 5.9

Correlations between Yield Components, by Variety Group (1983) VARIETY GROUP

Early glutinous Intennediate glutinous Late glutinous Nonglutinous

NUMBER IN SAMPLE

41 81 40 12

GRAIN WEIGHT AND PANICLES PER UNIT AREA

0.614 0.647 0.705 0.949

SOURCE: Miyagawa (personal communication), 1988.

GRAIN WEIGHT AND SPIKELETS PER PANICLE

0.465 0.538 0.053 0.637

PANICLES PER UNIT AREA AND SPIKELETS PER PANICLE

-0.351 -0.166 -0.351 +0.463

THE ENVIRONMENT AND RICE TECHNOLOGY

187

counted, it seems possible to replace these with intermediate nonglutinous varieties, which require almost identical cultivation conditions. The foregoing examination of rice cultivation, one based on the assumption that water stress is negligible, indicates that varieties and cropping schedules are chosen according to topographically determined water conditions, the need to spread the labor peak for transplanting, and the preference for glutinous over nonglutinous rice for home consumption. This set of factors defines a technological system that is well adapted to the given conditions. The performance of the nonglutinous varieties of the panicle-number type suggests that DD’s rice production might be increased simply by introducing some new varieties. This is particularly true if the recent tendency toward use of fertilizers becomes established. Such varieties should, like the existing nonglutinous ones, produce a greater number of spikelets per unit area and, hence, be of the panicle-number rather than panicle-weight type. What is wanted in DD, then, are glutinous varieties of the paniclenumber type in which the number of panicles and the number of spikelets per panicle do not cancel each other out under limited nutrient conditions. If the achievements made in improving nonglutinous varieties are any indication of what can be expected, the development of such glutinous varieties seems very highly likely. Incomplete ripening due to an excessive number of spikelets should not become an immediate problem unless a significantly reduced risk of crop failure by stabilization of the water supply allows the heavy application of fertilizers. The discussion presented above is based on findings in 1983, a bumper year for the rice crop. Further investigation is necessary to determine whether these conclusions are valid for drought years.

The Effects of Drought Nineteen eighty-one was a year of drought. The severity of drought, however, covers a wide range, and, by DD’s standards, the 1981 drought was mild. Drought damage is not limited to the damage suffered by rice that has been planted. Table 5-10 shows the planted areas in the low, middle, and high fields in Nong Simban in 1981 and 1983. In the drought year, lower proportions of the total area were planted in the middle and high fields than in 1983, but the differences were not large because the rainy season began earlier in 1981 than in 1983. Drought damage may thus also arise through the effect of the seasonal pattern of rainfall on the planted area.

CHAPTER 5

188

Table 5.10

Proportions of Paddy Land Planted in 1981 and 1983 LOW FIELDS

MIDDLE FIELDS

HIGH FIELDS

TOTAL

Total paddy field area (ha)

16.25

11.28

11.88

39.41

Area planted in 1981 (ha) Proportion planted (%)

15.98 98

8.96 79

10.00 84

34.93 89

Area planted in 1983 (ha) Proportion planted (%)

15.39 95

9.80 87

10.96 92

36.15 92

SOURCE: Kuroda and Miyagawa, 1987.

The average yield in 1981 of plots producing a measurable yield despite the drought damage was 182 grams per square meter, 77 percent of that in 1983. The frequency distribution of yield grades estimated from the cutting surveys in the two years, shown in figure 5-22, is skewed toward the low side in 1981 but almost normal in 1983, with a peak at 200-250 grams per square meter. Differences between the 2 years appear mainly on the low yield side. Even in the drought year of 1981, some plots experienced almost no water stress and gave yields close to the suggested maximum potential yields of 1983, while others experienced considerable water stress and gave very low yields. It is the latter that brought down the average yield for 1981. Table 5-11 compares the performances of the different variety groups assessed by the cutting survey in 1981 and 1983. The late and early glutinous groups gave almost the same average yields in the 2 years, while the other two groups showed a clear decline- in the drought year. In view of the clear correspondence between variety groups and topography and water conditions, it is evident that the differences between groups in the degree of drought damage do not represent genetic differences between them in drought resistance. 24 Nevertheless, the contrast between early glutinous and nonglutinous varieties is distinct. In 1981, the latter produced the lowest yield of the four variety groups, but, in 1983, they produced the highest, higher even than the late glutinous varieties. 25 The system of rice cultivation currently practiced in DD is highly adapted to the different kinds of paddy area that the villagers farm but not to drought or flooding. If there is any such adaptation, it is no more than the customary nonuse of fertilizers. 26 The use of small pumps and the beginnings of the use of power tillers can also be seen as modest attempts to cope with the problems. 27 Although the village has been greatly affected by droughts and floods, the problems have been insur-

189

THE E N V I R O N M E N T AND RICE T E C H N O L O G Y

Yield grade

Frequency

g/ m2

i

25
»n

o

o

ci

oo o o\ Cy w

m tn ci

c- o *n OK

»n oo oo c i co o *n KD T

o

o

o cy n o o \ r—1 T- tn t—