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The effects of timber logging on stand structure and species composition in north zamayi reserver forest, tharyarwddy district, myanma

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MINISTRY OF EDUCATION AND TRAINING MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT VIETNAM NATIONAL UNIVERSITY OF FORESTRY  MYO MIN THANT THE EFFECTS OF TIMBER LOGGING ON STAND STRUCTURE AND SPECIES COMPOSITION IN NORTH ZAMAYI RESERVE FOREST, THARYARWADDY DISTRICT, MYANMAR MASTER THESIS IN FOREST SCIENCE Hanoi, 2018 MINISTRY OF EDUCATION AND MINISTRY OF AGRICULTURE AND RURAL TRAINING DEVELOPMENT VIETNAM NATIONAL UNIVERSITY OF FORESTRY  MYO MIN THANT THE EFFECTS OF TIMBER LOGGING ON STAND STRUCTURE AND SPECIES COMPOSITION IN NORTH ZAMAYI RESERVE FOREST, THARYARWADDY DISTRICT, MYANMAR Major: Forest Science Code: 8620201 MASTER THESIS IN FOREST SCIENCE Signature: ………………………… Supervisor: Dr MANH HUNG BUI Hanoi, 2018 Abstract Natural forests in Myanmar are being managed based on sustainable forest management principle; under a regulation of Myanmar Selection System (MSS) since 1856 Notwithstanding the hundreds years of its reputation of good forest management and timbers that stand firmly as the essence of gross national proceeds, concerns over the longstanding practice of MSS is widely debated in term of sustainability when after the production forests were adversely threatened by degradation Although the mixed deciduous forests in Myanmar are renowned as legendary of teak bearing forests, the impact of selective logging, which has conducted annually over centuries, remains unknown Therefore, it needs the hands of the people, especially foresters and researchers Through research, scientists can provide the knowledge and understanding of the forest, including the structure and forest restoration This study was conducted at NZRF, Tharyarwaddy, Myanmar to evaluate the change of floristic characteristics, structure and regeneration potential of teak bearing forest in Bago region after selective logging in order to contribute the scientific findings to improve the silvicultural system applied to sustainable forest management in this region The evaluation based on data collected from one hectare of each forest types; forests after 10 years and 20 years of selective logging, in representative for two harvested sites in comparison with new data collected from one hectare of old-growth forest nearby as a control This study has obtained important findings Results show that, selective logging forests have been changed in all floristic characteristics, structure and regeneration potential in comparison with primary forest and between two harvested sites In floristic characteristics, this change is clear in species richness, species composition and species similarity The secondary forest is more homogeneous and uniform, while the old-growth forest is very diverse While in stand structure, the change is clear vertical and horizontal structure, diameter distribution, stand density, basal area, stock volume and volume increment Biodiversity of the overstorey in the secondary forest is more than the primary Density of regeneration is also shown a different between old-growth forest and harvested forest, between harvested forest sites The secondary forest still has mother trees and sufficient regeneration, so some restoration measures can be applied here Findings of the study contribute to improve people’s understanding of the structure and the structural i changes after harvesting in NZRF That is a key to have better understandings of the history and values of the forests These findings and the proposed restoration measures address rescuing degraded forests in Bago region in particular and Myanmar in general And further, this is a promising basis for the management and sustainable use of forest resources in the future Keywords: NZRF, Myanmar Selection System, reserve forest, natural regeneration, stand structure, species diversity, sustainable forest management ii CONTENTS Abstract …………… ………………………………………………………………i List of Figure …………….……….………………………………………………vi List of Table ……………… ………………………………….…………………viii Abbreviation ……………………………………………………………………… x CHAPTER I Introduction 1.1 Background Information 1.2 The state of Forest in Myanmar 1.3 Myanmar Selection System 1.4 Problem Statement 1.5 Objectives and research questions of the study 1.5.1 General Objectives 1.5.2 Specific Objectives CHAPTER II Literature Review 10 2.1 Tropical forest in the world 10 2.2 Deforestation 12 2.2.1 Major causes of deforestation 13 2.3 Tropical mixed deciduous forest in Myanmar 14 2.4 Deforestation and forest degradation in Myanmar 16 2.5 Review of AAC for timber harvesting in Myanmar 18 2.6 Sustainable tropical forest management 19 2.7 Silvicultrual management system of tropical forests 20 2.8 Stand structure, species dynamic and natural regeneration in natural forest 22 iii CHAPTER III Materials 24 3.1 General description of study site 24 3.1.1 Topography 25 3.1.2 Climate 26 3.1.3 History of silvicultural and forest management practices in the study site 28 CHAPTER IV Methodology 29 4.1 Establishment of permanent sample plots/ sampling design 29 4.2 Data collection method 31 4.2.1 Tree data collection 31 4.2.2 Coordinate of the tree 32 4.2.3 Data collection for regeneration 33 4.3 Data analysis method 34 4.3.1 Stand Information 34 4.3.2 Descriptive statistics for height and diameter variables 35 4.3.3 Linear mixed-effects analysis 38 4.3.4 Frequency distributions 38 4.3.5 Diameter-height regression analysis 40 4.3.6 Spatial point patterns of tree species 41 4.3.7 Tree species composition analysis results 41 4.3.8 Regeneration storey structure analysis 44 CHAPTER V Results and Discussion .45 5.1 Stand information 45 5.2 Descriptive statistics results 48 5.2.1 Vertical and horizontal projections 51 5.3 Linear mixed effect model results 53 5.4 Frequency distributions 55 5.5 Diameter-height regression results 63 5.6 Spatial distribution analysis 66 iv 5.6.1 Density testing results 66 5.6.2 Spatial distribution pattern testing 70 5.7 Tree species composition analysis results 74 5.7.1 Family composition 74 5.7.2 Species composition 77 5.7.3 Species similarity 79 5.7.4 Species Diversity 81 5.8 Regeneration storey structure analysis results 82 5.8.1 Height frequency distribution 82 5.8.2 Biodiversity index for regeneration 87 5.9 Silvicultural approaches for SFM in the North Zamayi RF 90 CHAPTER VI Conclusion .93 ACKNOWLEDGEMENT 96 REFERRENCES .97 APPENDIX ………………………………………………………………………105 v LISTS OF FIGURE FIGURE 2.1: FOREST COVERS AT DIFFERENT PERIODS IN MYANMAR 16 FIGURE 2.2: TREND OF CHANGES IN ‘OPEN FOREST’ TO ‘CLOSED FOREST’ IN MYANMAR 17 FIGURE 2.3: CHANGE OF AAC FOR TEAK (TECTONA GRANDIS) OVER 1995 TO 2011 AT COUNTRY LEVEL 18 FIGURE 2.4: CHANGE OF AAC FOR HARDWOOD SPECIES OVER 1995 TO 2011 AT COUNTRY LEVEL 18 FIGURE 2.5: NATIONAL INCOME FROM TIMBER EXPORT DURING 2000 TO 2012 19 FIGURE 3.1: LOCATION OF NORTH ZAMAYI RESERVE FOREST 25 FIGURE 3.2: CLIMATE DIAGRAM OF NORTH ZAMAYI RESERVE NEAR THARYARWADDY TOWNSHIP; DATA RECORDED FROM 2008 TO 2017 (METROLOGICAL DEPARTMENT, THARYARWADDY TOWNSHIP) 28 FIGURE 4.1: THREE DIFFERENT KINDS OF FOREST IN NZRF 29 FIGURE 4.2: SAMPLE PLOT 30 FIGURE 4.3: MEASURING POSITION OF DBH 31 FIGURE 4.4: DIAMETER MEASUREMENT BY USING A DIAMETER TAPE 32 FIGURE 4.5: HEIGHT MEASUREMENT BY USING A BLUE-LEISS 32 FIGURE 4.6: SUB-PLOTS FOR MEASURING TREE POSITION 33 FIGURE 4.7: REGENERATING TREE INVESTIGATION 33 FIGURE 5.1: VERTICAL AND HORIZONTAL PROJECTIONS FOR ALL FOREST TYPES 51 FIGURE 5.2: DIAMETER FREQUENCY DISTRIBUTION GRAPHS FOR OLD GROWTH FOREST 56 FIGURE 5.3: DIAMETER FREQUENCY DISTRIBUTION GRAPHS FOR 20 YEARS AFTER LOGGING FOREST 57 FIGURE 5.4: DIAMETER FREQUENCY DISTRIBUTION GRAPHS FOR 10 YEARS AFTER LOGGING FOREST 58 vi FIGURE 5.5: HEIGHT FREQUENCY DISTRIBUTION GRAPHS FOR OLD GROWTH FOREST 60 FIGURE 5.6: HEIGHT FREQUENCY DISTRIBUTION GRAPHS FOR 20 YEARS AFTER LOGGING FOREST 61 FIGURE 5.7: HEIGHT FREQUENCY DISTRIBUTION GRAPHS FOR 10 YEARS AFTER LOGGING FOREST 62 FIGURE 5.8: THE HEIGHT AND DBH RELATIONSHIP OF ALL STEMS WITH A DBH≥ CM OF OLD GROWTH FOREST IN NZRF 64 FIGURE 5.9: THE HEIGHT AND DBH RELATIONSHIP OF ALL STEMS WITH A DBH ≥ CM OF FOREST (AFTER 20 YEAR LOGGING) IN NZRF 64 FIGURE 5.10: THE HEIGHT AND DBH RELATIONSHIP OF ALL STEMS WITH A DBH≥ CM OF DEGRADED FOREST (AFTER 10 YEAR LOGGING) IN NZRF 65 FIGURE 5.11: TREE POSITION ON THE GROUND OF OLD GROWTH 67 FIGURE 5.12: TREE POSITION ON THE GROUND AFTER 20 YEARS OF LOGGING 68 FIGURE 5.13: TREE POSITION ON THE GROUND AFTER 10 YEARS OF LOGGING 69 FIGURE 5.14: DENSITY DISTRIBUTION 70 FIGURE 5.15: THE PAIR CORRELATION FUNCTION RESULTS OF OLD-GROWTH 71 FIGURE 5.16: THE PAIR CORRELATION FUNCTION RESULTS OF 20 YEARS AFTER HARVESTING 72 FIGURE 5.17: THE PAIR CORRELATION FUNCTION RESULTS OF 10 YEARS AFTER HARVESTING 73 FIGURE 5.18: REGENERATION HEIGHT FREQUENCY DISTRIBUTION FOR OLD GROWTH FOREST 83 FIGURE 5.19: REGENERATION HEIGHT FREQUENCY DISTRIBUTION FOR 20 YEARS AFTER LOGGING FOREST 84 FIGURE 5.20: REGENERATION HEIGHT FREQUENCY DISTRIBUTION FOR 10 YEARS AFTER LOGGING FOREST 85 FIGURE 5.21: REGENERATION SPECIES ACCUMULATION CURVES 88 vii LISTS OF TABLE TABLE 1.1: STATUS OF PERMANENT FOREST ESTATE TABLE 3.1: MONTHLY MEAN RAINFALL AND TEMPERATURE (2008-2017) AND DE MARTONNE’S ARIDITY INDEX FOR THARYARWADDY TOWNSHIP, 2018 27 TABLE 4.1: MEASURE OF DISPERSION AND VARIABILITY 36 TABLE 4.2: EQUATIONS USED FOR REGRESSION 40 TABLE5.1: STAND INFORMATION FOR PLOTS 46 TABLE 5.2: DESCRIPTIVE STATISTICS FOR DIAMETER VARIABLE 49 TABLE 5.3: DESCRIPTIVE STATISTICS FOR HEIGHT VARIABLE 52 TABLE 5.4: LINEAR MIXED EFFECT MODEL FOR DBH 53 TABLE 5.5: LINEAR MIXED EFFECT MODEL FOR H 54 TABLE 5.6: MOST IMPORTANT FAMILIES OF THE OLD GROWTH FOREST OF NZRF (ALL STEMS WITH A DBH ≥ 6CM) 75 TABLE 5.7: MOST IMPORTANT FAMILIES OF THE 20 YEARS AFTER LOGGING FOREST OF NZRF (ALL STEMS WITH A DBH ≥ 6CM) 75 TABLE 5.8: MOST IMPORTANT FAMILIES OF THE 10 YEARS AFTER LOGGING FOREST OF NZRF (ALL STEMS WITH A DBH ≥ 6CM) 76 TABLE 5.9: MOST IMPORTANT SPECIES OF THE OLD GROWTH FOREST OF NZRF (ALL STEMS WITH A DBH ≥ 6CM) 77 TABLE 5.10: MOST IMPORTANT SPECIES OF THE 20 YEARS AFTER LOGGING FOREST OF NZRF (ALL STEMS WITH A DBH ≥ 6CM) 78 TABLE 5.11: MOST IMPORTANT SPECIES OF THE 10 YEARS AFTER LOGGING FOREST OF NZRF (ALL STEMS WITH A DBH ≥ 6CM) 78 TABLE 5.12: THE SIMILARITY COEFFICIENT (KD) AMONG THE DIFFERENT FOREST TYPES (ALL STEMS WITH A DBH ≥ 6CM) IN NZRF 80 TABLE 5.13: DIVERSITY INDICES (SIMPSON, SHANNON-WEINER, AND EVENNESS) OF THREE DIFFERENT FOREST TYPES OF NZRF (ALL STEMS WITH A DBH ≥ 6CM) 81 viii 64 Villela, D.M., et al., Effect of selective logging on forest structure and nutrient cycling in a seasonally dry Brazilian Atlantic forest Journal of Biogeography, 2006 33(3): p 506-516 65 Khan, N., et al., Structure, diversity, and regeneration potential of Monotheca buxifolia (Falc.) A DC dominated forests of Lower Dir District, Pakistan Frontiers of Agriculture in China, 2011 5(1): p 106-121 66 Ei Thandar Bol, N.T., IMPACTS OF FOREST DISTURBANCE ON COMPOSITION, STRUCTURE AND FLORISTICS OF TROPICAL EVERGREEN FOREST, MON STATE, MYANMAR GLOBAL JOURNAL OF BIO-SCIENCE AND BIOTECHNOLOGY, 2017 6(3): p 415-424 67 Myo Min, T and H Bui Manh, RELATIONSHIPS AND SPATIAL DISTRIBUTION OF SPECIES IN NORTH ZAMARI RESERVE FOREST, THAYARWADDY, MYANMAR 2018 68 Fox, J.W., The intermediate disturbance hypothesis should be abandoned Trends in ecology & evolution, 2013 28(2): p 86-92 69 Le, S., Research on forest structure and proposal new selecting cutting system in Kon Ha Nung - Central Highlands (in Vietnamese), in Dissertation 1996, Forestry University of Vietnam: Hanoi p 129 70 Barbour, M.G., J.H Burk, and W.D Pitts, Terrestrial plant ecology 1980, Menlo Park, Davis, California, USA: California University 604pp 71 Thu, Z.M., Dynamics and management of moist evergreen dipterocarp forests in Mon State, Myanmar 2009, Universität Göttingen p 110 72 Yu Ya Aye, et al., Floristic Composition, Diversity and Stand Structure of Tropical Forests in Popa Mountain Park Journal of Environmental Protection, 2014 5(17): p 1588 73 Connell, J.H., Diversity in tropical rain forests and coral reefs Science, 1978 199(4335): p 1302-1310 74 Bradbeer, J., Seed dormancy and germination 2013: Springer Science & Business Media 103 75 Pham, Q.H., Structure and Light Factor in Differently Logged Moist Forests in Vu Quang-Huong Son, Vietnam, in Dissertation 2008, Georg-AugustUniversität Göttingen: Göttingen p 120 76 Fredericksen, T.S and B Mostacedo, Regeneration of timber species following selection logging in a Bolivian tropical dry forest Forest Ecology and Management, 2000 131(1): p 47-55 77 Champion, H.G., A preliminary survey of forest types of India and Burma Indian Forestry Record (NS) Silviculture, 1936 1(1) 78 Blanford, H., Highlights of one hundred years of forestry in Burma Empire Forestry Review, 1958 37(1 (91): p 33-42 79 Puettmann, K.J., Silvicultural challenges and options in the context of global change:“Simple” fixes and opportunities for new management approaches Journal of Forestry, 2011 109(6): p 321-331 80 Peña-Claros, M., et al., Regeneration of commercial tree species following silvicultural treatments in a moist tropical forest Forest Ecology and Management, 2008 255(3-4): p 1283-1293 81 Shiver, B.D and B.E Borders, Sampling techniques for forest resource inventory 1996: John Wiley and Sons 82 Data, M.F.I.a., Myanmar Forest Information and Data - Rainforests Mongabay.2011: Available on https://rainforests.mongabay.com/deforestation/2000/Myanmar.htm 104 APPENDIX Appendix List of instruments and materials for data collection for one plot Number No Items Purpose of tools GPS Current forest resources and soil maps Marker pen Boundary survey, and locating plots, and important ecological tree locations To determine plot locations and use in the field To label trees by using paper pieces 2 1000 m2-plot and m2-plot establishment Rope Linear tape For plot boundary delineation For locating plot boundary and for distance 500 m For plot marking measurement Chalk For marking the trees within the boundaries temporarily and for ensuring they are measured boxes Marking tapes For plot marking 500 m Poles (3m, 4m & m) Jungle knife To make the starting point of the plot by pythogro theory For cutting liana and bordering the plot Diameter and Height measurement 10 Linear tape 11 Diameter tape 12 1.3m sticks 13 Blue_Leiss 13 Worksheets For measuring the distance between the tree and to establish the plots For measuring the tree diameter For marking 1.3m position on the trunk For measuring the tree height For recording field data 105 2 2 Appendix Tree data collection No of data collection plot: …… Forest type: ……………………… Plot ID: …………………………… Canopy cover: …………………… Inventory date: …………………… Surveyor: ………………………… Forest status: ……………………… Location: ………………………… GPS location: ……………………… No Species name DBH H Coordinate X Quality Y (A,B,C) Notes: - This table will also be used to investigate tree positions for point pattern analysis 106 Appendix Regeneration investigation Regeneration plot number: …………… Plot number: …………………………… Forest type: ……………………………… No Species name H 107 Quality Appendix Appendix 4a: Tree species importance value index (IVI) of all stems with a DBH ≥ 6cm in Old-growth forest of NZRF No Species SIVI Lithocarpus fenestrata 5.759141 Albizzia odoratissima (L.f.) Benth 1.637657 Berrya mollis Wall Ex Kurz 6.705754 Bombax ceoba L 1.803172 Bombax insigne Wall 8.965374 Bridelia retusa (L.) Spreng 12.09264 Cordia grandis 4.730841 Croton oblongifolius Roxb 4.923216 Dalbergia cultrata Grah 4.510149 10 Dalbergia fusca Pierre 1.47444 11 Dalbergia ovata Grah 7.439558 12 Derris robusta 9.939655 13 Diospyros ehretioides 6.158116 14 Diospyros kurzii Hiern 16.26708 15 Duabanga grandiflora (Roxb Ex DC.) Walp 1.745373 16 Emblica officinalis 3.490068 17 Eriolaena candollei Wall 1.193655 18 Garuga pinnata Roxb 1.803172 19 Grewia tiliifolia Vahl 1.150375 20 Heterophragma adenophylla 3.483322 21 Holarrhena pubescens 1.717459 22 Homalium tomentosa Benth 2.614449 23 Lagerstroemia speciosa (L.) Pers 30.58 24 Lagerstroemia villosa Wall 1.222227 25 Lannea coromandelica (Houtt.) Merr 7.455573 26 Markhamia stipulata (wall.) Seem Ex K.Schum 3.790557 27 Microcos paniculata 1.540449 28 Millettia brandisiana Kz 6.791049 29 Millettia pendula Benth 4.774781 30 Mitragyna rotundifolia (Roxb.) Ktze 15.5967 108 31 Oroxlyum indicum (L.) Kurz 1.928354 32 Protium serratum Engl 1.269517 33 Schleichera oleosa (Lour.) Oken 10.16018 34 Schrebera swietenioides 1.792909 35 Spondias pinnata (L.) Kurz 2.584908 36 Stereospermum colais 13.08606 37 Tectona grandis L.f 14.0746 38 Terminalia chebula Retz 19.32374 39 Terminalia crenulata (Heyne) Roth 33.72548 40 Terminalia pyrifolia Kurz 1.433718 41 Vitex pubescens Vahl 10.47775 42 Xylia xylocarpa (Roxb.) Taub 8.78679 109 Appendix 4b: Tree species importance value index (IVI) of all stems with a DBH ≥ 6cm in 20 years after logging forest of NZRF No 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Species Lagerstroemia speciosa Pentace griffithii Sterculia villosa Acacia ferruginea Acrocarpus fraxinifolius Wight ex Arn Albizzia odoratissima (L.f.) Benth Anogeissus acuminata Wall Anthocephalus morindaefolius Antidesma bunius (L.) Spreng Artocarpus chaplasha Roxb Berrya mollis Wall Ex Kurz Bombax insigne Wall Bridelia retusa (L.) Spreng Chukrasia velutina Roem Cratoxylum ligustrinum Croton oblongifolius Roxb Dalbergia cultrata Dalbergia ovata Grah Dillenia parviflora Diospyros ehretioides Diospyros kurzii Hiern Duabanga grandiflora (Roxb Ex DC.) Walp Eriolaena candollei Wall Garuga pinnata Roxb Gmelina arborea Roxb Heterophragma adenophylla Holarrhena pubescens Homalium tomentosa Benth Lagerstroemia macrocarpa Kurz Lagerstroemia speciosa (L.) Pers 110 SIVI 5.123997 0.970412 2.79465 3.263984 2.109259 1.768516 37.30221 2.61735 1.932159 1.692196 12.90635 0.964362 6.091384 1.270113 1.152836 2.119059 1.330281 3.57404 2.69053 5.237471 2.811991 3.626864 2.324384 4.437766 9.630791 2.278374 1.052317 14.77921 1.821205 38.71487 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 Lagerstroemia villosa Wall Litsea glutinosa (Lour.) C.B.Rob Microcos paniculata Millettia brandisiana Kz Millettia pendula Benth Mitragyna pavifolia (Roxb.) Korth Mitragyna rotundifolia (Roxb.) Ktze Oroxlyum indicum (L.) Kurz Protium serratum Engl Pterospermum semisagittatum Buh.-Ham Spondias pinnata (L.) Kurz Sterculia angustifolia Stereospermum colais Swietenia macrophylla Syzygium grande (Wight.) Walp Tectona grandis L.f Terminalia bellerica Roxb Terminalia chebula Retz Terminalia pyrifolia Kurz Toona ciliaa M.Roemer Vitex pubescens Vahl Xylia xylocarpa (Roxb.) Taub 111 10.94508 5.272435 12.37749 11.63665 2.671864 3.161342 8.711583 2.226955 1.729891 4.130619 1.394827 3.639088 13.62249 1.768516 1.238463 3.051316 0.973786 1.305481 9.116575 2.913784 6.418225 13.30464 Appendix 4c: Tree species importance value index (IVI) of all stems with a DBH ≥ 6cm in 20 years after logging forest of NZRF No Species SIVI Acacia arabica Willd syn 1.196689 Acacia catechu Willd 0.764858 Albizia chinensis 0.882189 Albizia procera (Roxb) Benth 1.43012 Anogeissus acuminata Wall 9.734812 Artocarpus lakoocha 1.295914 Bauhinia malabrica Roxb 1.534924 Berrya mollis Wall Ex Kurz 0.975599 Bombax insigne Wall 6.786842 10 Bridelia retusa (L.) Spreng 10.27172 11 Careya arborea 0.830728 12 Cassia fistula L 4.305929 13 Chukrasia velutina Roem 0.764858 14 Cordia fragrantissima 1.102974 15 Cratoxylum ligustrinum 7.592374 16 Croton oblongifolius Roxb 12.83069 17 Dalbergia cultrata 2.113455 18 Derris robusta 5.952297 19 Dillenia parviflora 0.772427 20 Diospyros ehretioides 10.64835 21 Diospyros kurzii Hiern 4.364838 22 Duabanga grandiflora (Roxb Ex DC.) Walp 2.170957 23 Erythrina arborescens 4.941609 24 Gardenia sessiliflora 2.865026 25 Garuga pinnata Roxb 3.335126 26 Gmelina arborea Roxb 5.207543 27 Grewia laevigata Vahl 2.470629 28 Grewia tiliifolia Vahl 0.817136 29 Heterophragma adenophylla 1.602091 30 Holarrhena pubescens 4.204933 112 31 Homalium tomentosa Benth 19.33793 32 Hymenodictyon orixense 2.881861 33 Kydia calycina Roxb 1.580102 34 Lagerstroemia macrocarpa Kurz 5.291019 35 Lagerstroemia speciosa (L.) Pers 7.223574 36 Lagerstroemia tomentosa Persl 11.8029 37 Lagerstroemia villosa Wall 4.094649 38 Lannea coromandelica (Houtt.) Merr 2.337084 39 Markhamia stipulata (wall.) Seem Ex K.Schum 3.811873 40 Microcos paniculata 5.649994 41 Miliusa velutina 2.67454 42 Millettia brandisiana Kz 4.264165 43 Mitragyna parvifolia (Roxb.) Korth 0.999067 44 Mitragyna rotundifolia (Roxb.) Ktze 23.19217 45 Oroxlyum indicum (L.) Kurz 3.225126 46 Pterospermum semisagittatum Buh.-Ham 3.16992 47 Randia uliginosa DC 3.037435 48 Schleichera oleosa (Lour.) Oken 1.526881 49 Schrebera swietenioides 0.76607 50 Sterculia angustifolia 6.03669 51 Stereospermum colais 6.273013 52 Tectona grandis L.f 17.42019 53 Terminalia chebula Retz 3.300711 54 Terminalia crenulata (Heyne) Roth 6.458377 55 Terminalia pyrifolia Kurz 7.442035 56 Tetrameles nudiflora R.Br 10.77055 57 Vitex pubescens Vahl 4.528744 58 Xylia xylocarpa (Roxb.) Taub 16.3684 59 Pentace griffithii 0.767302 113 Appendix Appendix 5a Diameter frequency distributions of Old-growth forest in the NZRF 118.01 - 122.00 106.01 - 110.00 102.01 - 106.00 98.01 - 102.00 86.01 - 90.00 74.01 - 78.00 70.01 - 74.00 66.01 - 70.00 62.01 - 66.00 58.01 - 62.00 54.01 - 58.00 50.01 - 54.00 46.01 - 50.00 42.01 - 46.00 38.01 - 42.00 34.01 - 38.00 30.01 - 34.00 26.01 - 30.00 22.01 - 26.00 18.01 - 22.00 14.01 - 18.00 10.01 - 14.00 Plot No 6.01 - 10.00 DBH classes 11 2 0 0 0 0 0 3 0 0 0 0 0 3 3 4 0 0 0 0 0 0 0 0 0 1 0 0 0 1 1 1 0 0 0 0 0 4 1 0 0 0 0 0 6 0 0 0 0 0 0 0 2 0 0 0 0 0 12 14 0 0 0 0 0 0 10 13 5 1 0 0 0 0 0 114 Appendix 5b Diameter frequency distributions of 20 years after harvesting forest in the NZRF 118.01 - 122.00 106.01 - 110.00 102.01 - 106.00 98.01 - 102.00 86.01 - 90.00 74.01 - 78.00 70.01 - 74.00 66.01 - 70.00 62.01 - 66.00 58.01 - 62.00 54.01 - 58.00 50.01 - 54.00 46.01 - 50.00 42.01 - 46.00 38.01 - 42.00 34.01 - 38.00 30.01 - 34.00 26.01 - 30.00 22.01 - 26.00 18.01 - 22.00 14.01 - 18.00 10.01 - 14.00 Plot No 6.01 - 10.00 DBH classes 15 2 1 0 0 0 0 0 0 1 0 0 0 0 0 0 5 0 2 0 0 0 0 0 0 0 0 0 0 0 0 52 11 0 0 0 0 0 0 1 2 1 0 0 0 0 0 41 16 13 0 0 0 0 0 0 8 5 0 0 0 0 0 0 0 9 0 1 0 0 0 0 0 0 10 4 3 1 0 0 0 0 0 115 Appendix 5c Diameter frequency distributions of 10 years after harvesting forest in the NZRF 118.01 - 122.00 106.01 - 110.00 102.01 - 106.00 98.01 - 102.00 86.01 - 90.00 74.01 - 78.00 70.01 - 74.00 66.01 - 70.00 62.01 - 66.00 58.01 - 62.00 54.01 - 58.00 50.01 - 54.00 46.01 - 50.00 42.01 - 46.00 38.01 - 42.00 34.01 - 38.00 30.01 - 34.00 26.01 - 30.00 22.01 - 26.00 18.01 - 22.00 14.01 - 18.00 10.01 - 14.00 Plot No 6.01 - 10.00 DBH classes 23 2 0 0 0 0 0 0 0 0 46 11 0 0 0 0 0 0 0 0 36 1 0 0 0 0 0 0 0 0 34 30 0 0 0 0 0 0 0 0 0 57 2 0 0 0 1 0 0 0 0 0 34 16 0 0 0 0 0 0 0 91 0 0 0 0 0 0 0 0 0 0 48 20 1 0 0 0 0 0 0 0 0 43 2 0 0 0 0 0 0 0 0 0 10 49 11 0 0 0 0 0 0 0 0 0 116 117 ... study the focus is to evaluate logging and its effects on stand structure and composition as implication in relation to deforestation and forest degradation 1.2 The state of Forest in Myanmar Myanmar,... productivity, and sustainability [44] Understanding tree composition and structure of forest is a vital instrument in assessing the sustainability of the forest, species conservation, and management of. ..MINISTRY OF EDUCATION AND MINISTRY OF AGRICULTURE AND RURAL TRAINING DEVELOPMENT VIETNAM NATIONAL UNIVERSITY OF FORESTRY  MYO MIN THANT THE EFFECTS OF TIMBER LOGGING ON STAND STRUCTURE

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