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Best Management Practices for Agricultural Non-Point Sources of Pollution

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Best Management Practices for Agricultural Non-Point Sources of Pollution CEP Technical Report: 41 1998 BEST MANAGEMENT PRACTICES FOR AGRICULTURAL NON-POINT SOURCES OF POLLUTION CONTENTS Page Tables............................................................................................................................................................ v Figures ......................................................................................................................................................... vi Acronyms....................................................................................................................................................vii SECTION 1. INTRODUCTION ............................................................................................................ 1 1.1 Background ............................................................................................................... 1 1.2 Purpose and Scope.................................................................................................... 2 SECTION 2. REGIONAL OVERVIEW ............................................................................................... 5 2.1 Geographic Area ....................................................................................................... 5 2.2 Land Use and Water Resources ................................................................................ 5 2.3 Socioeconomic Conditions—Agriculture, Industry, and Resources......................... 7 SECTION 3. AGRICULTURAL NONPOINT SOURCE POLLUTION......................................... 13 3.1 Introduction............................................................................................................. 13 3.2 Agricultural Non-point Sources of Pollution .......................................................... 14 3.2.1 Cultivation.................................................................................................. 14 3.2.2 Livestock Production................................................................................. 23 3.3 Agricultural Pollutants and Their Sources .............................................................. 27 3.3.1 Sediment .................................................................................................... 28 3.3.2 Nutrients..................................................................................................... 31 3.3.3 Pesticides.................................................................................................... 33 3.3.4 Pathogens ................................................................................................... 35 3.3.5 Solid Waste................................................................................................ 37 SECTION 4. BEST MANAGEMENT PRACTICES ......................................................................... 39 4.1 Introduction............................................................................................................. 39 4.2 Nonstructural BMPs................................................................................................ 41 4.2.1 Education ................................................................................................... 41 4.2.2 Water Management.................................................................................... 45 4.2.3 Land Use.................................................................................................... 46 4.2.4 Erosion and Sediment Control ................................................................... 46 4.2.5 Pesticide/Nutrient Control..........................................................................50 4.2.6 Pathogens ................................................................................................... 55 4.2.7 Solid Waste................................................................................................ 57 4.3 Structural BMPs...................................................................................................... 58 4.3.1 Erosion and Sediment Controls.................................................................. 58 4.3.2 Pathogens ................................................................................................... 63 4.3.3 Solid Waste................................................................................................ 64 4.3.4 Siting Structural BMPs .............................................................................. 64 4.4 Monitoring .............................................................................................................. 65 4.5 Socioeconomic Factors and Implementation .......................................................... 66 United Nations Environment Programme—CAR/RCU Page iii CEP Technical Report No. 41 CONTENTS (continued) SECTION 5. CASE STUDIES.............................................................................................................. 69 5.1 The Better Bananas Program .................................................................................. 69 5.2 Plan Sierra............................................................................................................... 70 5.3 Technical Improvements to Local Innovations in Haiti.......................................... 72 SECTION 6. MEETING SUMMARY................................................................................................. 75 SECTION 7. CONCLUSION ............................................................................................................... 85 GLOSSARY .............................................................................................................................................. 87 REFERENCES CITED ............................................................................................................................ 91 APPENDIX A Site Visits APPENDIX B Abstracts by Title APPENDIX C Additional Resources APPENDIX D Better Bananas Certification Program United Nations Environment Programme—CAR/RCU Page iv CEP Technical Report No. 41 TABLES Page Table 1-1. The Cartagena Convention signatory countries and territories ................................................. 1 Table 2-1. Projected land use changes in the WCR.................................................................................... 6 Table 2-1. Principal rivers draining into the WCR..................................................................................... 6 Table 2-3. Windward Islands banana revenue............................................................................................ 7 Table 2-4. Land use percentage changes in croplands, pasturelands, and forest woodlands in 17 countries of the WCR during the 1977-1989 period ................................................................. 9 Table 2-5. Leading agricultural producers in the WCR............................................................................ 10 Table 2-6. Leading sugarcane and banana producers in the WCR ........................................................... 11 Table 3-1. Percent deforestation in WCR countries and territories .......................................................... 15 Table 3-2. Agricultural land use in the WCR ........................................................................................... 17 Table 3-3. Pesticide use in banana production on the eastern Caribbean islands..................................... 19 Table 3-4. Herbicides used in banana production..................................................................................... 21 Table 3-5. Herbicides used in sugarcane production................................................................................ 22 Table 3-6. Herbicides used in cotton production...................................................................................... 24 Table 3-7. Agricultural activities that potentially affect water quality..................................................... 27 Table 3-8. Average annual fertilizer use in 17 countries of the WCR, including changes during the 1979-1989 period............................................................................................................... 32 Table 3-9. Average annual pesticide use in 14 countries of the WCR, including changes during the 1974-1984 period............................................................................................................... 36 Table 4-1. Some examples of traditional systems of soil management, vegetation, and water use by farmers..................................................................................................................................... 39 Table 4-2. Effectiveness and limitations of nonstructural BMPs ............................................................. 42 Table 4-3. Estimates of potential reductions in field losses of pesticides for cotton compared to a conventionally or traditionally cropped field ................................................................... 54 Table 4-4. Estimates of potential reductions in field losses of pesticides for cotton compared to a conventionally or traditionally cropped field ................................................................... 63 Table 4-5. Economic returns from soil conservation in Maissade, Haiti.................................................. 67 Table 6-1. Contaminants/pollutants of concern, sources, causes, and practices for control..................... 78 Table 6-2. Obstacles to implementation and suggested solutions ...........................................................
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