Page 1 of 54 Environment and Society in the Lower Mekong Basin: A Landscaping Review VOLUME I Pamela McElwee and Michael M Horowitz prepared for the Mekong River Basin Research and Capacity Building Initiative, Oxfam America SEA 15 197-99 by the Institute for Development Anthropology 1999 FOREWORD This review of the literature on the lower Mekong basin peoples and their production systems has been prepared by the Institute for Development Anthropology (IDA) to contribute to Oxfam America's "Mekong River Basin Research and Capacity-Building Initiative." At their meeting at Can Tho University in January 1998, and in Ho Chi Minh City in January 1999, the participating organizations in this initiative, which include Can Tho University, the International Center for Living Aquatic Resource Management, the International Institute of Rural Reconstruction, Oxfam America - Southeast Asia Regional Office, and IDA, agreed to focus initially on environmental and socioeconomic dimensions of rural areas in the Mekong Delta. Hence, the review largely considers the literature of that part of the basin in Vietnam and Cambodia, but it also includes upstream materials from Cambodia beyond the delta and from Lao Peoples Democratic Republic. The review is presented in two volumes. The first volume is a substantive discussion of the region as drawn from the literature. It is intended only as a guide to the literature and does not pretend to be comprehensive in any of its sections. The second volume is bibliographic. In order that the material remain fresh, we plan on issuing periodic updatings of the review for the duration of the Initiative activity. Therefore, Initiative partner organizations and other readers are warmly encouraged to share corrections, alternative interpretations of the material, and suggestions on improved organization of the document, and to advise us of additional bibliographic materials. Where these materials are "grey" or "fugitive" limited- circulation documents, we should be most grateful to receive hard copies as well as the Page 2 of 54 references. Pamela McElwee and Michael M Horowitz Institute for Development Anthropology 99 Collier Street, PO Box 2207 Binghamton, New York 13902-2207 USA Tel. 1-607-772-6244 Fax 1-607-773-8993 E-mail: [email protected] TABLE OF CONTENTS Section One: Introduction 1 1. Development on River Basins 1 2. The Mekong 5 3. The Lower Mekong Basin and Delta 7 Section Two: Ecology and Environment 18 1. Topography 18 2. Climate 20 Drought 22 Fires 23 Climate Change 23 Tributaries 24 3. The Great Lake 24 Flow 24 Chemical Content and Pollution 28 Sediment loads 29 Floods 31 Tides 33 Water Use in Lower Basin 33 Groundwater 34 4. Soils 34 Mechanical properties of the Delta soils 35 Page 3 of 54 Chemical properties 36 pH 37 Acid soils 39 Salinity 39 Siltation 41 Discussion 41 5. Aquatic communities 42 6. Plant communities 48 Plain of Reeds 49 Swamp forests of Tonle Sap 50 Mangroves 51 Protected areas 55 7. Animal communities 56 Mammals 56 Birds 57 8. War damage 58 Section Three: Agriculture and Other Production Systems 61 General Overview 61 1. Rice Farming 62 Variation in Rice Crops 67 Single transplanted main season rice 68 Double transplanted rice 68 Broadcast main season rice 68 Dry season rice 68 Rainfed Rice 69 Floating Rice 70 Rice Improvement Facilities 71 Integration with Other Agricultural Products 72 Flooding 73 Irrigation: 74 Groundwater use 77 Page 4 of 54 Water Users 77 Pesticides 77 Fertilizers 79 Mechanization 80 Credit and Markets 80 2. Other Farm Crops 82 3. Fishing and Aquaculture 86 Subsistence Fishing 86 Commercial Fishing 87 Effects of Darn Development on Fisheries 90 Aquaculture 91 Shrimp/Mangrove Farming 93 4. Forestry 95 Timber 97 Fuelwood and Charcoal 98 Other Forestry Products 98 5. Livestock 99 6. Gardening 100 7. Other Agricultural Systems 102 Beekeeping 103 Hunting 103 Sericulture 104 Coffee 104 8. Markets and Trading 104 9. Other Rural Enterprises 106 Mining 106 Industry 106 10. Land Tenure and Property Rights 106 Conclusion 112 Section Four: Sociocultural Issues 115 1. History of Settlement 115 2. Page 5 of 54 Ethnicity 120 3. Population 126 4. Income and Poverty 129 5. Health and Nutrition 135 6. Education 141 7. Settlement Patterns 143 Housing 144 Urbanization 146 Transportation 147 8. Household and Village Structures 149 Family Structure 149 Extra-family Structures 150 Village Structures 150 9. Gender 151 10. Religion 157 Section Five: Conclusion 167 References Cited 171 List of Tables Table 1. Average Slope of Water Surface of Mekong During Dry Season 20 Table 2. Weather Statistics for Lower Mekong Basin 23 Table 3. Major Tributaries of the Mekong River 27 Table 4. Flow Rate Averages for the Mekong River 98 Table.5. Sediment Loads* Deposited by Various River Systems 30 Table 6. Water Use in Vietnam by Region 1995, in 10 million m3 35 Table 7. Mechanical Composition of Soil by Country 37 Table 8. Percentage of Total Organic Carbon in Air-dried Soil Samples 37 Table 9. Chemical Composition of Vietnamese Delta Soils 38 Table 10. pH Levels by County in Mekong Basin 38 Table 11. Nitrogen Content of Soil Samples in Mekong Basin 39 Table 12. Carbon/Nitrogen Ratios 39 Page 6 of 54 Table 13. Caution Exchange Capacity 39 Table 14. Standing Crop Estimates for Various Fishery Habitats 47 Table 15. Type of Land and Water Resources in Cambodia 50 Table 16. Uses for Mangrove Species in Traditional Medicine in the Mekong 55 Delta Table 17. Exploitation of Mangrove Areas in Minh Hai, Vietnam, 1975-1983 56 Table 18. Benefits from Mangrove Restoration in Northern Vietnam 57 Table 19. General Statistics for the Mekong Delta, 1993 61 Table 20. Total Agricultural Production in Rice Equivalent in thousand tons 63 1976-1990, for Vietnam Table 21. Total Sown Area of Rice per Year, 1976-1990 in Mekong Delta 65 Table 22. Farmer Households in the Mekong Delta 1980-1991 65 Table 23. Rice Production Equivalent per Capita 1976 and 1990 66 Table 24. Rice Productivity in Cambodia, 1960-1992 67 Table 25. Main Groups of Local Rice Varieties in the Mekong Delta 68 Table 26. The Average Labor Input into Different Rice Regimes in the Delta 71 Table 27. Percentage of Rice Land under Cropping Systems, Mekong Delta 72 Table 28. Irrigation Expansion in Mekong Basin Countries 1980-1990 75 Table 29. Fertilizers Consumed in 1965-66 79 Table 30. Tractors in Service and Ratio to People in 1973 80 Table 3 1. Land Use in Southern Vietnamese Agriculture in 1970 82 Table 32. Total Area under Soybean Production in Mekong Delta 1976 and 1990 84 Table 33. Sown Area of Jute in Mekong Delta 84 Table 34. Sown Area of Coconut Palms in Mekong Delta 85 Table 35. Sown Area of Pineapple in Mekong Delta 85 Table 36. Estimated Total Fisheries Production and Consumption of Fish 86 Products per Person per Year (1974) Table 37. Fish Catches from Mekong System in 1973 87 Table 38. Composition of the Commercial Fish Catch in Vietnam 88 Table 39. Composition of the Commercial Fish Catch in Cambodia 89 Table 40. Water Surface Used for Aquaculture in 1987 and 1991 in Mekong 91 Delta Page 7 of 54 Table 41. Production of Aquaculture Products by Tons, 1991 92 Table 42. Production of Sea Fish in Tons, 1991 92 Table 43. Suggestions for Improving Shrimp Yields in Shrimp-Mangrove 94 Systems Table 44. Area of Forests by Type and Thousand ha in Mekong Delta in 1989 96 Table 45. Cashews in Mekong Delta in 1990 99 Table 46. Livestock in Several Countries in 1973 99 Table 47. Vegetables Cultivated in Gardens in the Upper Delta, 1964 100 Table 48. Fruits Cultivated in Gardens 102 Table 49. Land Distribution under the French 107 Table 50. Major Features of Agricultural Policy Regimes, 1976-1995 111 Table 51. Sites of Historical Interest in Lower Mekong Basin 116 Table 52. Ethnicity in Vietnam, 1993 121 Table 53. Ethnicity in Ratanakiri Province NE Cambodia, in 1996 121 Table 54. Income Distribution of Ethnicities in Mekong Delta, 1988 123 Table 55. Population Structure in Cambodia, 1990 126 Table 56. Population Structure in Vietnam 1989 126 Table 57. Vietnam Population by Province in 1976 and 1991 128 Table 58. Vietnam Population by Province in 1995 and Urban/Rural Distribution 128 Table 59. Population in Cambodia by Province, 1981 and 1993 129 Table 60. Household Incomes Compared across Regions in Vietnam 131 Table 61. Incidence of Poverty by Region in Vietnam, 1993, in percentages of 131 people living below the government poverty line Table 62. Rural Income Distribution by Region 1989-1992 132 Table 63. Infant Mortality and Literacy Rates for Vietnam, 1993 136 Table 64. Infant Mortality and Literacy Rates for Cambodia, 1993 136 Table 65. Cambodia Health Indicators, 1990 137 Table 66. Vietnam Health Indicators, 1993 137 Table 67. Vietnam Medical Care Indicators 1991-1996 138 Table 68. Cambodia Medical Care Indicators, 1993 138 List of Figures Page 8 of 54 Figure 1. General Path of the Mekong 4 Figure 2. Map of the Lower Mekong Basin 15 Figure 3. Map of Districts and Political Subdivisions in the Basin 16 Figure 4. Topographic Map 22 Figure 5. Hydrographs 26 Figure 6. Map of Saline Intrusions 31 Figure 7. Map of Modem Cities and Archaeological Sites in the Mekong Valley 117 Figure 8. Population Density of the Lower Mekong Basin. Source: White (1962) 127 Section One. Introduction At the outset we need to point out, as this report makes clear, that dam construction for hydropower, navigation, flood control, and irrigation is not the only, nor necessarily the most profound change affecting the lower Mekong region and its peoples.