Faculty of Forest, Geo and Hydro Sciences: Institute of Forest Growth and Forest Computer Sciences The effect of site selection on the growth of Dipteryx panamensis in timber plantations in Costa Rica and Panama by Fabian Schmidt A thesis submitted in partial fulfillment of the requirements for the degree Master of Science in Tropical Forestry and Management Faculty of Forest, Geo and Hydro Sciences University of Technology, Dresden, Germany Date of Submission: 30. September 2009 Scientific supervisor: Prof. Dr. rer. silv. habil. Heinz Röhle Institute of Forest Growth and Forest Computer Sciences University of Technology, Dresden, Germany Co-supervisor: Dr. rer. silv. Hubertus Pohris Institute of International Forestry and Forest Products University Technology, Dresden, Germany Local advisor: Dr. Olman Murillo Instituto Tecnológico de Costa Rica, Cartago, Costa Rica Lending admitted / not admitted Dresden, September 2009 TABLE OF CONTENTS TABLE OF CONTENTS TABLE OF CONTENTS ............................................................................................................ i ABSTRACT ........................................................................................................................... iv ACKNOWLEDGEMENTS ....................................................................................................... v LIST OF ABBREVIATIONS ..................................................................................................... vi LIST OF FIGURES ................................................................................................................. vii LIST OF TABLES ................................................................................................................. viii LIST OF EQUATIONS ............................................................................................................ ix 1. INTRODUCTION ..................................................................................................... 10 1.1 Research justification ................................................................................................ 11 1.2 Research objectives ................................................................................................... 12 1.3 Research questions .................................................................................................... 13 2. LITERATURE REVIEW .............................................................................................. 14 2.1 Species information ................................................................................................... 14 2.2 Almendro in timber plantations ................................................................................ 16 2.3 Agroforestry and carbon forestry using Almendro ................................................... 19 3. METHODOLOGY ..................................................................................................... 21 3.1 Study area .................................................................................................................. 21 3.2 Description of the sample plots ................................................................................. 22 3.3 Data collection ........................................................................................................... 23 3.4 Data analysis .............................................................................................................. 24 3.5 Growth modeling ....................................................................................................... 28 3.6 Stand height curves ................................................................................................... 29 3.7 Site classification ....................................................................................................... 31 4. RESULTS ................................................................................................................. 33 4.1 Growth of Almendro in Costa Rica and Panama ....................................................... 33 4.1.1 Site group 1, CR .................................................................................................. 33 4.1.2 Site group 2, CR .................................................................................................. 34 i TABLE OF CONTENTS 4.1.3 Site group 3, CR .................................................................................................. 35 4.1.4 Site group 4, CR .................................................................................................. 38 4.1.5 Site group 5, CR .................................................................................................. 42 4.1.6 Site group 6, CR .................................................................................................. 44 4.1.7 Site group 7, PA .................................................................................................. 46 4.1.8 Site group 8, PA .................................................................................................. 50 4.1.9 Site group 9, PA .................................................................................................. 52 4.2 Stand characteristics of Almendro plantations ......................................................... 53 4.2.1 Stem diameter distribution ................................................................................ 54 4.2.2 Stand height curves ............................................................................................ 56 4.3 Growth dynamics of Almendro ................................................................................. 58 4.3.1 Mean annual increment of Almendro ................................................................ 59 4.3.2 Top height growth .............................................................................................. 60 4.4 Preliminary site indices for Almendro ....................................................................... 61 4.5 Top-height projections .............................................................................................. 63 5. DISCUSSION ........................................................................................................... 66 5.1 Data basis ................................................................................................................... 66 5.2 The effect of site selection ........................................................................................ 68 5.2.1 Site index calculation and top height projection ............................................... 70 5.2.2 Frequency of site index classes .......................................................................... 71 5.2.3 Promising regions for Almendro plantations ..................................................... 73 5.3 Silviculture ................................................................................................................. 73 5.3.1 Initial spacing and stand density ........................................................................ 74 5.3.2 Thinning and pruning ......................................................................................... 75 5.4 Timber production on Almendro plantations ........................................................... 77 5.5 Carbon forestry .......................................................................................................... 79 ii TABLE OF CONTENTS 5.6 Agroforestry ............................................................................................................... 81 5.7 Limitations of the present study ............................................................................... 83 5.8 Recommendations ..................................................................................................... 83 6. CONCLUSION ......................................................................................................... 84 BIBLIOGRAPHY .................................................................................................................. 85 APPENDICES ...................................................................................................................... 94 Appendix 1 - Detailed information on sampled Almendro plantations ............................... 94 Appendix 2 - Stand diameter distribution ............................................................................ 95 Appendix 3 - Stand height curves ......................................................................................... 98 Appendix 4 - Estimated Parameter values ......................................................................... 102 Appendix 5 - Photos ........................................................................................................... 104 EIDESSTATTLICHE ERKLÄRUNG ......................................................................................... 108 iii ABSTRACT ABSTRACT Plantation forestry is of high importance in both Central American countries, Costa Rica and Panama, who promote the establishment of timber plantations through government incentive programs. While most plantation companies plant exotic tree species such as Teak (Tectona grandis), local farmers tend to prefer native species, which are often better adapted to low intensity management and poor soils. More and more companies also start to diversify their product portfolios by using native species. The potential of native tree species is enormous, but research