Analyzing nearest neighborhood characteristics of a tropical evergreen forest at k’bang district gia lai province using time series data

MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT VIETNAM NATIONAL UNIVERSITY OF FORESTRY STUDENT THESIS ANALYZING NEAREST NEIGHBOR CHARACTERISTICS OF A TROPICAL EVERGREEN FOREST AT K’BANG DISTRICT, GIA LAI PROVINCE, USING TIME SERIES DATA Major: Natural Resources Management Code: D7850101 Faculty: Forest Resources and Environmental Management Student: Vu Manh Cuong Student ID: 1453091211 Class: K59A Natural Resources Management Course: 2014 – 2018 Advanced Education Program Developed in collaboration with Colorado State University, USA Supervisor: Dr Nguyen Hong Hai Hanoi, June 2018 CONTENTS CONTENTS LIST OF FIGURE CHAPTER - INTRODUCTION 1.1 Forest and forestry in Vietnam 1.2 Selective logging in tropical forests 1.3 Selective logging in Vietnam 1.4 Forest structure and Dynamics 1.5 Nearest Neighbor Characteristics CHAPTER - MATERIALS AND METHODS 2.1 Study site 2.2 Topography and soil 2.3 Forest resources 12 2.4 History of silvicultural and forest management practices in the study site 13 2.5 Data collection and analysis 14 2.5.1 Sampling design 14 CHAPTER - RESULTS AND DISCUSSION 19 3.1 Tree species diversity and composition 19 CHAPTER – CONCLUSION 30 4.1 Tree species diversity and composition 30 4.2 Tree dynamics 31 4.3 Nearest neighbor characteristics 32 REFERENCES 33 APPENDIX 38 LIST OF FIGURE Figure 2.1 The location of the study site in Gia Lai Province, Central Highlands of Figure 2.3 Climate diagram of Vinh Son, near the study site, data recorded from 1990 to 2010 (Nguyen et al., 2011) 11 Figure 2.5 Layout of sample plot 15 Figure 2.6: Definition of the spatial parameters: Mingling (a), Dominance (b) and Uniform Angle Index (c) 18 Figure 3.1 Simpson diversity indices of three forest types from 2004-2012 19 Figure 3.2 Shannon diversity indices of three forest types from 2004-2012 19 Figure 3.3 Evenness diversity indices of three forest types from 2004- 2012 20 Figure 3.4 Species richness of three forest types from 2004 - 2012 21 Figure 3.5 Tree abundance of three forest types from 2004- 2012 21 Figure 3.6 Change diameter of three forest types from 2004- 2012 24 Figure 3.7 Change High of three forest types through time series 25 Figure 3.8 Mortality of three forest types through time series 26 Figure 3.9 Recruitment of three forest types through time series 27 Figure 3.10 Mingling characteristics of all trees in three study plots 28 Figure 3.11 DBH characteristics of all trees in three study plots 28 Figure 3.12 Uniform Angle Index characteristics of all trees in three study plots 29 CHAPTER - INTRODUCTION 1.1 Forest and forestry in Vietnam Forest vegetation in Vietnam is diverse as a result of differing climatic conditions and topographic/latitudinal variations (Thai, 1978; USAID, 2013) Vietnam has at present 13.9 million hectares of forest covering 39.9% of its total land area; of these, 10.4 million hectares (75.2%) are natural forests (FPD, 2013) that can be classified into eight major forest groups: (1) close-mixed evergreen broad-leaved rainforest, (2) semi-deciduous mixed forest; (3) mixed limestone forest; (4) coniferous and mixed coniferous broadleaved forest; (5) sparse forest, seasonal deciduous forest, and Dipterocarps-dominant forest; (6) mangrove forest; (7) Melaleuca forest (i.e., forest on alum land); and (8) bamboo and mixed timber-bamboo forest As it is the case concerning other tropical forests, Vietnam‟s forests are high in diversity, and up to hundreds of different tree species can be found within one hectare (Whitmore, 1990; Richards, 1996) The result is a high level of biomass and productivity (Vanclay, 1991a; Le, 1996; Sam, 2004; Gunter et al., 2011) 1.2 Selective logging in tropical forests The term "selective logging" is used to describe forest management techniques, namely harvesting valuable trees on a stem diameter with rules designed to maintain forest cover (Lobo et al., 2007) According to Rapera (1977) cited by Johns (1985), selective logging is defined as “the removal of mature, over mature and defective trees in such a manner as to leave uninjured an adequate number and volume of healthy residuals of commercial species and other tree species, necessary to assure a future crop of timber and forest cover for the protection of soil and water” Silviculture systems are usually classified as multiring or round depending on the number of harvested activities in a forest in a rotation system (Smith and Nichols, 2005); Selective mining is a multi-ring system (Lamprecht, 1989) Selective logging is considered a better practice than clear cutting (Gatti et al., 2014) It is increasingly being accepted as an approach to protecting forest integrity and enabling the proper use of resources This silvicultural technique is widely used because the growers want to keep the immature seedlings alive for future crops In other words, after the selective logging, the rest retained the main structural elements of the forest as well as the various ecological niches maintaining high levels of biodiversity and keeping the ecosystem functioning in a way to facilitate faster recovery of pre-harvested values (Nzogang, 2009) However, in practice, selective logging systems tend to intensify to the extent that they lead to the conversion of logged forests into secondary forests (Gadow, 2012) The longterm sustainability of such forests for particular species and size of timber is uncertain The future success of a selective harvesting system may depend on the number of commercial trees extracted per unit area (Whitmore, 1984) A highly mechanized logging operation is largely random in its effects because the overall damage is severe and certainly not limited to commercially important crops (Johns, 1985) 1.3 Selective logging in Vietnam Selective logging is the most popular and widely employed method for commercial timber production in Vietnam This silvicultural system has been applied to natural forests since 1960, often under the name “selected cutting with natural regeneration” (MARD, 1993; Le, 1996; Ho, 1999; MARD, 2005a) This method was also implemented in the study site The main objective of this silvicultural system is to improve the efficiency of harvesting operations, avoid unnecessary damage to the remaining trees, decrease forest degradation, and increase the high yield for the next cutting cycles (MARD, 1993; Le, 1996; MARD, 2005a) The selected cutting with natural regeneration system (MARD, 1993) can be described as follows:  Applied forests have a standing volume ≥ 130 m3 per ha;  The minimum diameter at breast height (DBH) for cutting is determined by timber groups; it ranges from 40 to 50 cm DBH;  The cutting cycle is 35 years,  The maximum cutting intensity is 38 % of the total standing volume In Vietnam‟s selective logging practice, only commercial species and the best stems are concentrated on, while other non-commercial species are not objectives despite their mature status (Ho, 1999) Consequently, the quality of the remaining stems and forest is adversely affected, and the number of individuals per hectare decreases Such a harvesting system not only directly affects species‟ resilience it also poses a risk to the genetic diversity of natural forests and natural regeneration because it eliminates seed dispersals (Le, 1996; Ho, 1999) Studying the effects of selective logging on forest structures, natural regeneration, and forest dynamics in Vietnam is thus necessary 1.4 Forest structure and Dynamics Forest structure Forest structure‟ refers to the way in which the attributes of trees are distributed within a forest ecosystem (Gadow, 2012), this structure is a product of forest dynamics, a driver of ecosystem processes and biological diversity (Speis, 1998) In other words, forest structure is the result of natural processes and human disturbance (Gadow et al., 2002) Understanding forest structure is key to determining harvest events and stimulating the forest dynamics that follow them (Gadow, 2012) Without adequate descriptions and understanding of forest structure and diversity, one runs the risk of being unable to follow a silvicultural prescription or learn from the resulting successes or mistakes Oliver and Larson (1990) defined the forest structure as "the physical distribution and time of the tree in a place." The main forest structure attributes are the type of structure, size, shape and spatial distribution of the components (Speis, 1998) Forest structures can be described based on inventory data such as tree abundance, average diameter, average height, bottom area, standing mass and frequency distribution as well as quantitative information (Brodbeck, 2004) Forest dynamics Forest dynamics encompasses the changes in forest structure and species composition over time, as well as the forest‟s behavior in response to anthropogenic and natural disturbances (Oliver and Larson, 1990) Understanding the dynamics of the forest is fundamental to developing sound management systems for harvesting and/or conserving forest resources by predicting future forest structures and development patterns (Oliver and Larson, 1990) The determination of forest and tree growth, which is measured via tree diameter (Swaine et al., 1987b), is of major importance for forest managers Information on diameter increments and growth patterns for each species relates to forest stand productivity It is therefore essential data for sustainable forest management (SFM) In addition, the diameter increment has become the most important variable for an allometric equation (Vanclay, 1994) and as such plays a key role in examining the dynamics of a natural forest Changes in the species composition reflect the natural restoration of disorders (Okali and OlaAdams, 1987) In tropical forests, it is difficult to estimate these changes as many species are represented by only a few individuals (Swaine et al., 1987b) According to Okali and Ola-Adams (1987), the species composition of the large canopy and the emergence species in the secondary rainforest can be identified early in the development of a standing tree Basic knowledge about the changes in species composition in tropical forests remains limited due to the lack of long-term studies on demographic change and tropical forest species 1.5 Nearest Neighbor Characteristics Structural characteristics of forest stand can be describe as the distribution characteristics of individuals of the same species, which is typically represented by different diameters and tree ages In a given space, population structure is vulnerable to isolation from other populations within the same community, therefore, for any tree species in a mixed forest, interspecific and intraspecific differences in tree size, species mingling and distribution patterns may be the most important characteristics of population structure Distribution patterns directly reflect the way individuals assemble or scatter in space, which may in turn be associated with conditions of competition and utilization of environmental resources among adjacent trees Tree size is directly related to the degree of maturation of a tree population and to the competitive advantage of the population within the community, it may also be directly related to the survive viability and ecological niche of the population Intraspecific aggregation involves isolation between species in the same community, and the process is close to seed dispersal, regeneration capacity and growth A number of methods for describing forest structural attributes have been largely developed for decades However, an exact description of small-scale structural attributes is considered to be increasingly importance Recently, new individual tree indices, such as uniform angle index, species mingling and dominance (Gadow et al.1999; Hui et al 1999), have been developed The basic idea of these indices is to characterize the neighborhood of a reference tree by its using n-nearest neighbors The techniques of nearest neighbor statistics allow us determining the relationship within neighborhood groups of trees such as species and size class at small scales This method has several advantages over using expression frequency to depict the attributes among individuals when compared to the traditional methods For instance, greater inhomogeneity in species and homogeneity in size classes indicate greater structural diversity (Gadow et al 2012) Our overall goal is to characterize spatial attributes of neighborhood trees by applying the current techniques of nearest neighbor statistics For a better understanding of structural units, we combined three structural units for each species in analyses, such as mingling-uniform angle index, mingling-dominance and dominance-uniform angle index CHAPTER - MATERIALS AND METHODS 2.1 Study site This study was conducted in the Kon Ha Nung region of Vietnam‟s Central Highlands, a region with one of the highest amounts of forest cover (50% of the total land area) (Nguyen, 2009) The total forest area in Kon Ha Nung is approximately 126,000 ha, most of which is classified as moist evergreen forests (Le, 1996; Ho, 1999) These forests, in one of the major production forest areas in Gia Lai Province (Joern, 2010), are considered to be an area of exceptional biological and cultural diversity (Pollard, 2005) However, forest cover in the central highlands has declined in recent years from 53,9% in 1999 to 50,9% in 2012 (FPD, 2013) Increasing demands for forest products such as timber, non-timber products, and firewood It is possible to put more pressure on some of the remaining forest areas However, the secondary forest area is increasing (Le, 2012) But without exception, the rate of deforestation in Kon Ha Nung remains high, leading to a decline in overall forest quality (Le, 1996; Ho, 1999; Joern, 2010) As a result, increased concern about the remaining forests must be protected and forest disturbance restored 80 71 70 Number of tree 60 50 40 43 37 32 30 22 17 20 10 UL LIL 2008 HIL 2012 Figure 3.8 Mortality of three forest types through time series Comparing three forest types shows that mortality tend to increase with the levels of disturbance (UL, LIL, and HIL) Mortality= 17 to 71(number of tree) Compare for each forest type through time, we can see UL has change in mortality for years (2008-2012), mortality= 37 to 43 (number of tree) In LIL, mortality tend to increase from (2008-2012) Mortality= 22 to 32 HIL has mortality tend to increase more than (UL, LIL) from 2008-2012 mortality= 17 to 71(number of tree) Recruitment Recruitment appears to be related to logging intensity, reaching its height in the HIF This pattern would be expected due to an increase in suitable conditions for regeneration (soil and light disturbance) However, a lower level of recruitment in the LIF was more difficult to interpret but may be the result of selective logging that left only a small number of robust trees 26 90 81 80 66 Number of tree 70 57 60 50 40 30 20 10 17 UL LIL 2008 HIL 2012 Figure 3.9 Recruitment of three forest types through time series Comparing three forest types shows that Recruitment tend to increase with the levels of disturbance (UL, LIL, and HIL) recruitment = to 66 (number of tree) Compare for each forest type through time, we can see UL has change in recruitment for years (2008-2012), recruitment = 17 to 57 (number of tree) In LIL, recruitment tend to increase from (2008-2012) recruitment = 22 to 32 (number of tree) HIL has recruitment tend to increase more than (UL, LIL) from 2008-2012 recruitment = to 81 (number of tree) 3.3 Nearest neighbor characteristics We used only data recorded in 2012 to analyze with nearest neighbor characteristics due to recruitment and mortality did not chance significantly from 20042012 27 Mingling Figure 3.10 Mingling characteristics of all trees in three study plots Analyzed results of Kon Ha Nung plot was shown in Figure.3.10 Showed species mixture (Mingling) concentrated at high levels from high mixture to complete mixture, M= 0.1-0.89 These evidences shown that these dominant species were highly mixed with other tree species in adjacent neighbors DBH dominance Figure 3.11 DBH characteristics of all trees in three study plots DBH dominance to nearest neighbor, the results showed that these species were less advantage in DBH comparing to their nearest neighbors DBH has been described through three time series (unlogged, Low impact logged, High impact logged) DBH= 0.190.24 28 Uniform Angle Index Figure 3.12 Uniform Angle Index characteristics of all trees in three study plots Uniform Angle Index shows spatial distribution of reference individuals to their nearest neighbors Dominant species were regular to clumped pattern with W= 0.01-0.63 These evidences shown that these uniform angle index were random with other tree species in adjacent neighbors 29 CHAPTER – CONCLUSION 4.1 Tree species diversity and composition High tree species richness and diversity tend to be a general property of the moist evergreen forest in Kon Ha Nung in comparison with the world‟s other tropical forests In this study, a total of 100 species belonging to 46 families were recorded in 2012 (from 70 to 86 species ha-1) The Shannon-Wiener index (H‟) varied between 3.7 and 3.9; the Simpson index (D) ranged 0.9; and the Evenness index from 0.57 to 0.61 in these forests, Species richness tend to increase with the from 74 to 93(number of species), Tree abundance tend to increase with number of trees= 503 to 674(number of tree), DBH also increase with DBH = 22.22 to 27.41(cm) Moreover, Tree height dynamics also tend to increase with the High = 17.8 to 26.7(cm).The most dominant families in the Kon Ha Nung forests were Myrtaceae, Lauraceae, Magnoliaceae, Sapindaceae, Burseraceae, Euphorbiaceae, and Fagaceae, while at species level the forests were mainly composed of Paramichelia braianensis, Dialium cochinchinensis, Machilus odoratissimus, Dacryodes dungii, Baccaurea harmadii, Castanopsis poilanei, Pometia ecomtei, Pasania ducampii, Aglaia silvestris, and Nephelium bacsasense Kon Ha Nung‟s moist evergreen forests were dominated by different combinations of species, meaning that none of the three forest types was a mono-dominant forest Varying selective logging intensities did not demonstrate significant impacts on the patterns of tree diversity and species composition The species composition of the logged forests tended toward similarity with the UF Slight differences among the three forest types at both the family and species levels demonstrated a 90% resemblance in the total species Similar results were also found when comparing diversity indices, but no significant differences in these indices were found among the three forest types In other words, selective logging resulted in minimal levels of damage to diversity, as indicated by Shannon-Wiener's (H), Simpson's (D), and the Evenness indices (J); here, the two logged 30 forests had diversity values comparable to those of the UF In the long-term, it is clear that the tree community would return to something close to its previous state In spite of this, the forest may never fully recover its original diversity due to the negative impact persistent invasive species may have on native species diversity 4.2 Tree dynamics There is little difference between the three types of forest related changes species composition, diversity, forest structure, standing dynamics and growth, all concerned about the intensity of logging The results show that UL species composition is more stable than two disturbing forests, as evidenced by the slow change in species composition and lack of change in the ten most important UL species In contrast, initial consecutively (eg, Pometia lecomtei, Polyalthia laui, etc.) always decrease their importance over time in high impact logged and low impact logged sites These species have been replaced by species that are intermittently discontinuous and have no bright colors (for example, Paramichelia braianensis), a change indicating that high impact logged and low impact logged sites will be closer to species composition of the UL Furthermore, different logging intensities led to different stem dynamics among the three forest types, with results indicating that a high logging grade had a higher proportion of tree abundance recruiting in comparison with a lower intensity or the unlogged This occurred due to the removing of large stems, which in turn led to the enlargement of gaps and the increased available resources for recruitments There was no evidence that mortality rates differed among forest types All forest stands showed a similar pattern of increasing basal area and stand volume No significant differences in mean basal area (standing volume) growth rates were found among stands under different logging intensities for the period of 2004-2012; however, diameter increments were markedly influenced by logging intensities, a result made evident through the observation of diameter increment trends over time in the three 31 forest types Overall, annual diameter increments varied between 0.2 – 0.3 mm Median diameter increments in both the unlogged and low impact logged sites were lower than those in the high impact logged 4.3 Nearest neighbor characteristics Spatial structure is one of the key parameters to describe standing forest structure We calculated and described structural parameters such as Mingling, DBH dominance and Uniform Angle Index by using Crancod and Microsoft Excel softwares The results showed that: most of studied species were found highly mixed with other species, M= 0.10.89 These evidences shown that these dominant species were highly mixed with other tree species in adjacent neighbors In DBH dominance analysis, DBH= 0.19- 0.24 the results showed that these species were less advantage in DBH comparing to their nearest neighbors Uniform Angle Index shows spatial distribution of reference individuals to their nearest neighbors, Dominant species were regular to clumped pattern with W= 0.010.63 These evidences shown that these uniform angle index were random with other tree species in adjacent neighbors 32 REFERENCES Ngo Van Cam, 2015.Long-term effects of logging on structures and dynamics of moist evergreen forests in Kon Ha Nung, Central Highlands of VietnamThai, Brodbeck, F., 2004 Structure and Processes in Traditional Forest Gardens of Central Sulawesi, Indonesia Cuvillier Verlag Goettingen, Goettingen, Germany Pommerening A & Stoyan D (2006) Edge-correction needs in estimating indices of spatial forest structure Canadian Journal of Forest Research 36(7): 1723-1739 Alder, D., Synnott, T.J., 1992 Permanent sample plot techniques for mixed tropical forest Department of Plant Sciences, University of Oxford, Oxford PPC, 2008 Degree No 53/QD-UBND dated 04 Feb 2008 reclassified the Gia Lai forest into categories: special use, production and protection forest (in Vietnamese) In: Forestry, D.o (Ed.) 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Forest Science Institute of Vietnam, Hanoi 37 APPENDIX List of tree species in all three plots: Number 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Vietnamese name Ba bét đỏ Ba bét trắng Bạc Bồ Bơ rừng Bời lời cam bốt Bưởi bung Cẳng gà Chân chim Chẹo tía Chìa vơi Chịi mịi Chơm chơm Cị ke Cóc đá Cơm nhỏ Cơm to Côm tầng Cứt ngựa Dạ hương Dâu gia đất Dẻ Dung Dung nhỏ Dung to Dung sành Dung trứng Giổi Giổi bà Giổi nhung Gội nếp Gội tẻ Hoa khế Hoắc quang Hồng rừng Kháo Kháo nhỏ Kháo to Kháo lông Khế rừng Scientific name Mallotus metcalfianus Mallotus apelta Croton argyratus Sapindus mukorossi Persea sp Litsea cambodiana Acronychia pendunculata Pteris semipinnata Schefflera octophylla Engeldharta chrysolepis Enddlela asiatica Antidesma corriaceum Nephelium bacsasense Microcos paniculata Dacryodes dungii Elaeocarpus lanceifolius Elaeocarpus apiculatus Elaeocarpus dubius Archidendron robisonii Disoxylum loureiri Lansium domesticum Quercus sp Symplocos dung Symplocos sp2 Symplocos sp3 Symplocos lucida Symplocos sp5 Talauma gioi Michelia balansae Paramichelia braianensis Aglaia gigantea Aglaia silvestris Nuihonia sclerantha Wendlandia paniculata Diospyros tonkinensis Machilus odoratissimus Machilus thunbergii Machilus parviflora Machilus robusta Averrhoa sp 38 Family Euphorbiaceae Euphorbiaceae Euphorbiaceae Sapindaceae Lauraceae Lauraceae Rutaceae Pteridaceae Araliaceae Juglandaceae Enddleiaceae Euphorbiaceae Sapindaceae Tiliaceae Burseraceae Elaeocarpaceae Elaeocarpaceae Elaeocarpaceae Mimosaceae Meliaceae Meliaceae Fagaceae Symplocaceae Symplocaceae Symplocaceae Symplocaceae Symplocaceae Magnoliaceae Magnoliaceae Magnoliaceae Meliaceae Meliaceae Ericaceae Rubiaceae Ebenaceae Lauraceae Lauraceae Lauraceae Lauraceae Oxalidaceae 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 Kim giao Lát xoan Lèo heo Lim xẹt Lòng mang Mặt cắt Máu chó Máu chó to Mít nài Ngát Nhãn rừng Nhọ nồi Nhọc Ơ rơ Re Re bầu Re gừng Re nhỏ Re to Săng đá Săng máu Sao cát Sến đất Sến mủ Sồi phảng Sữa Sung Thạch đảm Thanh thất Thị rừng Thôi ba Thôi chanh Thông nàng Thông tre Trám Trâm Trám chim Trâm đỏ Trám hồng Trâm nhỏ Trâm to Trâm móc Trâm nước Trâm to Podocarpus fleuryi Choerospondias axillaris Polyalthia nemoralis Peltophorum ferrugineume Pterospermum heterophyllum Rapanea neriiflolia Knema corticosa Knema pierrei Artocarpus asperula Gironniera subacqualis Dimocarpus fumatus Diospyros pilosella Polyalthia laui Prunus fordiana Cinnamomum sericans Cinnamomum obtusifolium sp Cinnamomum obtusifolium Cinnamomum albiflorum Cinnamomum sp Linociera sangda Horsfieldia sp Anisoptera robusta Sinosideroxylon sp Shorea roxburghii Castanopsis cerebrina Alstonia scholaris Ficus harlandii Tristania sp Ailanthus malabarica Diospyros silvatica Alangium chinense Marlea begoniaefolia Podocaropus imbricatus Podocaropus brevifolius Canarium sp Eugenia brachyata Canarium tonkinensis Syzygium zeylanicum Canarium subulatum Syzygium sp1 Syzygium sp2 Syzygium jambos Syzygium ripicola Syzygium hancei 39 Podocarpaceae Anacardiaceae Annonaceae Caesalpiniaceae Sterculiaceae Myrsinaceae Myristicaceae Myristicaceae Moraceae Ulmaceae Sapindaceae Ebenaceae Annonaceae Rosaceae Lauraceae Lauraceae Lauraceae Lauraceae Lauraceae Oleaceae Myristicaceae Dipterocarpaceae Sapotaceae Dipterocarpaceae Fagaceae Apocynaceae Moraceae Sp Simaroubaceae Ebenaceae Alanginacea Cornaceae Podocarpaceae Podocarpaceae Burseraceae Myrtaceae Burseraceae Myrtaceae Burseraceae Myrtaceae Myrtaceae Myrtaceae Myrtaceae Myrtaceae 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 Trâm sán thủy Trâm sừng Trám trắng Trâm trắng Trám trâu Trôm Trường Tu hú Ươi Vạng trứng Xoài rừng Xoan đào Xoan mộc Xoay Xương cá Syzygium polyanthum Eugenia chanlos Canarium album Syzygium wightianum Canarium littorale Sterculia foetida Pometia lecomtei Callicarpa arborea Sterculia lychnoflora Endospermum sinesis Swintonia pierrei Spondias dulcis Toona febrifuga Dialium cochinchinensis Canthium dicoccum 40 Myrtaceae Myrtaceae Burseraceae Myrtaceae Burseraceae Sterculiaceae Sapindaceae Verbenaceae Sterculiaceae Euphorbiaceae Anacardiaceae Anacardiaceae Meliaceae Caesalpiniaceae Rubiaceae ... Podocarpaceae Anacardiaceae Annonaceae Caesalpiniaceae Sterculiaceae Myrsinaceae Myristicaceae Myristicaceae Moraceae Ulmaceae Sapindaceae Ebenaceae Annonaceae Rosaceae Lauraceae Lauraceae Lauraceae... Lauraceae Lauraceae Lauraceae Oleaceae Myristicaceae Dipterocarpaceae Sapotaceae Dipterocarpaceae Fagaceae Apocynaceae Moraceae Sp Simaroubaceae Ebenaceae Alanginacea Cornaceae Podocarpaceae Podocarpaceae... Euphorbiaceae Sapindaceae Tiliaceae Burseraceae Elaeocarpaceae Elaeocarpaceae Elaeocarpaceae Mimosaceae Meliaceae Meliaceae Fagaceae Symplocaceae Symplocaceae Symplocaceae Symplocaceae Symplocaceae