B I OD I V E R S I TA S Volume 21, Number 9, September 2020 Pages: 4405-4418 ISSN: 1412-033X E-ISSN: 2085-4722 DOI: 10.13057/biodiv/d210960 Heterospecific and conspecific associations of trees in lowland tropical forest of New Guinea AGUSTINUS MURDJOKO1,2,♥, MARTHEN MATHIAS JITMAU2, DONY ARISTONE DJITMAU1, RIMA HERLINA SETIAWATI SIBURIAN1, ANTONI UNGIRWALU1, ALFREDO OTTOW WANMA1, ZULFIKAR MARDIYADI1, ALEXANDER RUMATORA1, WOLFRAM YAHYA MOFU1, ANTON SILAS SINERI1, SEPUS MARTEN FATEM1, DESCARLO WORABAI1, NUNANG LAMAEK MAY 1, MAX JONDUDAGO TOKEDE1, HERMAN WARMETAN1, CHARLY BRAVO WANGGAI1, JIMMY FRANS WANMA1, ELIESER VIKTOR SIRAMI1,2, JOHANA BETY PAEMBONAN3, ERNI UNENOR4, RELAWAN KUSWANDI5, KRISMA LEKITOO5, LISNA KHAYATI5, NITHANEL MIKAEL HENDRIK BENU5, JUNUS TAMBING5, ANDI SASTRA BENNY SARAGIH6 1Faculty of Forestry, Universitas Papua. Jl. Gunung Salju, Amban, Manokwari 98314, West Papua, Indonesia. ♥email: agustinus.murdjoko.papua@gmail.com 2Research Center of Biodiversity, Universitas Papua. Jl. Gunung Salju, Amban, Manokwari 98314, West Papua, Indonesia 3Environmental Services, Pegunungan Bintang District. Oksibil, Pegunungan Bintang 99573, Papua Province, Indonesia 4Forestry Service, Papua Province. Jl. Tanjung Ria Base G 99771, Tanjung Ria, Jayapura City 99117, Papua, Indonesia 5Forestry Research and Development Agency of Manokwari. Jl. Inamberi-Susweni, Manokwari 98301, West Papua, Indonesia 6Perkumpulan Mnukwar. Jl. Manunggal Besar, Amban, Manokwari 98314, West Papua, Indonesia Manuscript received: 22 August 2020. Revision accepted: 29 August 2020. Abstract. Murdjoko A, Jitmau MM, Djitmau DA, Siburian RHS, Ungirwalu A, Wanma AO, Mardiyadi Z, Rumatora A, Mofu WY, Sineri AS, Fatem SM, Worabai D, May NL, Tokede MJ, Warmetan H, Wanggai CB, Wanma JF, Sirami EV, Paembonan JB, Unenor E, Kuswandi R, Lekitoo K, Khayati L, Benu NMH, Tambing J, Saragih ASB. 2020. Heterospecific and conspecific associations of trees in lowland tropical forest of New Guinea. Biodiversitas 21: 4405-4418. The vegetation in the tropical rainforest of New Guinea consists of a large number of species that interact with each other within and among species. While several studies have attempted to reveal the diversity of flora of New Guinea, little is known about plant communities that develop associations. This study aimed to investigate the associations of tree species in lowland tropical forest in New Guinea. The associations depicted in this study were in the form of conspecific associations (among small and large individuals within same species) and heterospecific (among individuals of different species and divided into under and upper story). We established 48 rectangular plots created in Murkim and Teiraplu as part of Pegunungan Bintang District, Papua Province. Canonical correspondence analysis (CCA) was used to analyze heterospecific and conspecific associations. The results showed that the understory and upper story vegetation had different patterns of heterospecific association. The understory configured three heterospecific associations, consisting of 5, 13, and 90 species, while the upper story formed four heterospecific associations with 4, 8, 11, and 63 species. The analysis of conspecific associations showed of 149 tree species recorded in the study sites, only 66 species that had both small and large individuals, displaying the pattern of conspecific association. Among them, 41 species had positive associations while 25 species had negative associations. Our findings enrich the knowledge in theoretical ecology of tropical forests, especially in New Guinea. Keywords: Canonical correspondence analysis, CCA, Papuasia, tree community, tropical rainforest, vegan package INTRODUCTION Tropical rainforest is a complex ecosystem with many interactions between abiotic and biotic factors, particularly among vegetation (Vitousek 1984; Thomas and Baltzer 2002; Hunter et al. 2015). This complexity results in the vegetation that consists of many life forms from vertical and horizontal compositions that interact with each other to obtain sunlight, soil nutrients, and water, and to adapt with microclimatic conditions (Slik et al. 2015, 2018; Murdjoko et al. 2016a). The interactions among vegetation have occurred over a long period due to successional process (Fernández-Lugo et al. 2015). Where the vegetation shares the same ecological condition, the morphological and physiological characters become the driving factors of behavior in the natural tropical rainforest (Gustafsson et al. 2016; Johnson et al. 2017). The interactions among vegetation elements in the tropical rainforest in some cases represent symbiosis and inter and intra-species relationships (Legendre and Fortin 1989; Magrach et al. 2014). These interactions can be in the form of competition and association. In old tropical rainforest, the interaction occurs intensively due to the absorption of light and water, where both are the primary growth factors (Yamamoto 2000; Montgomery and Chazdon 2001). In secondary forest, canopy gap is very open, leading to more light penetrating the forest floor (Itoh et al. 1997; Angelini et al. 2015; Murdjoko et al. 2017). The association in vegetation communities can be in the form of conspecific or heterospecific and the form of association determines the pattern of the spatial distribution of forest ecosystems either. Conspecific association is the interaction of individuals of similar species while heterospecific occurs among different species of vegetation 4406 B I OD I V E R S I TA S 21 (9): 4405-4418, September 2020 (Zhu et al. 2015; Wang et al. 2018). Conspecific and heterospecific associations occur during the successional process of the tropical rainforest (Farneda et al. 2018). Some studies explained that the association, either the conspecific or the heterospecific could be in a positive or negative pattern (Castilla et al. 2016). Vegetation is distributed geographically with the diversity and pattern of plant communities that adapt to particular ecological niche (Brummitt 2001; Pan et al. 2013). Phytogeographic regions, including mainland New Guinea, have been studied for centuries. The vegetation in New Guinea spreads from coastal to high land areas, containing various types of ecosystems (Cámara-Leret and Dennehy 2019). As the result, New Guinea contains the highest diversity of flora, such as trees, climbers, shrubs, ferns, rattan, etc. (Murdjoko et al. 2016a) in which about 60% of the species are endemic (Cámara-Leret et al. 2020). For example, a forest area in New Guinea consists of a high diversity of tree species with more than 70 species per hectare that could be found (Robiansyah 2018; Fatem et al. 2020). While recently more and more studies have attempted to reveal the diversity of flora of New Guinea, little is known about plant communities that develop associations among them. This study aimed to investigate the association of tree species in the lowland tropical forest in New Guinea. The associations depicted in this study were in the form of conspecific associations (among small and large individuals within same species) and heterospecific (among individuals of different species and divided into under and upper story). We hypothesized that the small and large tree species have heterospecific associations within the natural tropical rain forest. This kind of study is important to provide specific contribution of ecological research in the tropical rainforest of Southeast Asia, more specifically the New Guinea region (Brummitt 2001). MATERIALS AND METHODS Study period and area This study was conducted in the northern part of Pegunungan Bintang District (Ind.: kabupaten), Papua Province, Indonesia (Figure 1). The study sites were located at Murkim (4°0'0.53"S and 140°49'17.24"E) and Teiraplu (3°59'13.46"S and 140°26'0.06"E) at an altitude of 155 m and 233 m above sea level (m asl), respectively. The ecosystem type of the two study sites are categorized as lowland areas where the southern part is bordered with the mountain range and the northern part is bordered with hills while the western and eastern parts are lowlands. Broadleaves and mixed forests are the dominant vegetation in this area, while the soil is grouped as Ultisols and Inceptisol. The climatic conditions are considered to be very humid with average temperature of 25° C for annual, 20.6° C for daily, and 16.3° C for minimum, and with monthly and annual average rainfall of 448.75 mm and 5385 mm, respectively (Kartikasari et al. 2012). Sampling and data collection Data were collected using sampling plot method with size of each plot 20 m x 20 m. In total, there were 48 rectangular plots established in which 24 plots were in Teiraplu and 24 plots were in Murkim. In both locations, the plots were placed to north directions at a distance of 100 m away from each other. In the 20 m x 20 m plot (A) we recorded and measured old trees with a diameter of more than 20 cm, and within this plot we established three nested sub-plots with size 10 m x 10 m (B) to record tree with diameter between 10 cm and 20 cm, size 5 m x 5 m (C) to record trees taller than 1.5 m, and size 2 m x 2 m (D) to record the species shorter than 1.5 m. The vegetation in plots A and B were classified as upper story and that in plots C and D were categorized as understory. For the understory vegetation, we recorded data of taxonomic names of every species and number of individuals, and while for the upper story vegetation we recorded data of taxonomic names of every species, number of individuals, and diameter (cm). For identification, we collected the specimens of the plant and sent it to the Herbarium Papuaense of Balai Penelitian dan Pengembangan Lingkungan Hidup dan Kehutanan (BP2LHK) Manokwari and Herbarium Manokwariense (MAN) Pusat Penelitian Keanekaragaman Hayati Universitas Papua (PPKH-UNIPA), Manokwari. The species name was updated according to The Plant List (TPL) at the website of http://www.theplantlist.org/. Statistical analysis The heterospecific and conspecific associations were analyzed using the canonical correspondence analysis (CCA) (Ter Braak 1986; Caceres and Legendre 2009), and the chi-square test (χ2) was implemented to validate the model of CCA (Fatem et al. 2020). Furthermore, this association used the number of each individual (density) as a value in which the columns were the species and the rows were the 48 plots. The conspecific association correlated the under and upper story as small and large individuals. The columns represented the species, while the 48 plots under and upper story represented the rows. The species that did not have under and upper stories were otherwise excluded. The result of CCA displayed species in the graph with the position in the two axes. To investigate the conspecific association whether it was positive or negative, the Euclidean distance between each species as well as the under and upper stories were conducted (Murdjoko et al. 2016b, 2017). If the result of Euclidean distance of species is below the average, then the conspecific association is said to be positive, and vice versa. The vegan package in R version 3.5.3 was used to calculate the statistical analysis (Oksanen et al. 2019). MURDJOKO et al. – Associations of New Guinea tree 4407 Figure 1. Map of the study sites in Teiraplu and Murkim, Pegunungan Bintang, Papua, Indonesia RESULTS AND DISCUSSION Heterospecific associations The heterospecific association was grouped into two: understory and upper story, based on the structure of trees in tropical forests. As such, the analyses of multivariate statistics for the understory and upper story were separated since the natural tropical rainforest is complex with the vegetation structures forming the ecosystem. The structure was also simplified by distinguishing them into two main parts. From the CCA result, the understory and upper story showed different patterns of heterospecific association. The understory configured three groups of communities based on species as the structure of the associations. The three groups are shown in Figure 2. The results showed that 108 species of trees formed the association in natural tropical forests, and was valid statistically as χ2 = 10.686, df = 2461, p-value = 1. The species of understory showed heterospecific associations as tree groups where the first consisted of 90 species (blue boxes), the second contained 13 (green boxes), and the third comprised of 5 species (red boxes) (Figure 2). The name of the species in the boxes in Figure 2 was abbreviated and the complete name can be seen in Table S1. The CCA result showed that the upper story vegetation community had a pattern of association with a valid result of χ2 = 11.344, df = 1955, p-value = 1. The upper story consisted of 86 species which formed four heterospecific associations, consisting of the first group (63 species) in the grey boxes, second group (11 species) in the red boxes, third group (8 species) in the purple boxes, and fourth group (4 species) in the blues boxes (Figure 3). The complete name of species presented in Figure 3 can be seen in Table S2. The association pattern of the understory and upper story differed from one another even though they grew in the same natural forest. The difference in association has likely resulted from the variation of the vertical structure of the tropical forest. The upper story vegetation has reached the emergent layers of forest canopy, allowing species to benefit by getting more sunlight (Murdjoko et al. 2016a, 2017; Fatem et al. 2020). The formation of understory was caused by competition due to it is below the canopy layers with low solar radiation (Rüger et al. 2011; Laurans et al. 2014; Angelini et al. 2015). For centuries, the formation of tropical forests has been a sequential process in which large numbers of species compete dynamically each other (Brown et al. 1990; Wright and Muller-Landau 2006; Liu and Slik 2014; Almeida et al. 2019). The heterospecific association can be related to the fact that trees interact with each other to form symbiosis with other life forms, such as liana, fern, herb, epiphyte, etc. (Johnson et al. 2017; Cirimwami et al. 2019; Steege et al. 2019). The primary factor influencing the pattern of tree communities of understory and upper story during tropical forest succession was probably caused by the abiotic factors, especially to gain nutrients, water, and sunlight as materials to support metabolisms, especially photosynthesis. Nonetheless, many studies showed that the morphological and physiological characters have also affected different responses of species to grow and develop (Goodale et al. 2012; Gustafsson et al. 2016). For example, the nature of shade tolerance species may be a factor that allows small tree species to survive the competition and obtain limited sunlight below the canopy layers (Givnish 1999; Montesinos-Navarro et al. 2018). Therefore, it is 4408 B I OD I V E R S I TA S 21 (9): 4405-4418, September 2020 crucial to study the shade-tolerant characters of a species in the rainforest in order to explain forest dynamics in more detail. This study is unable to reveal such characters concerning the light competition because that is beyond the scope is this study. Conspecific associations The analysis of conspecific associations was conducted using 149 species that grew in the study sites, but only 66 species that had small and large individuals as understory and upper story. The result of CCA showed statistically valid result as χ2= 5.8784, df = 2904, p-value = 1 (Figure 4). In addition, it displayed the pattern of conspecific association as 41 species had positive association while 25 species had negative association. In the positive association, the small and large individuals of the 41 species were distributed closely in the same area, representing the tendency of mature trees to reproduce and germinate. Conversely, in the negative association, the small individuals of the 25 species grew mainly far from the large ones that represent the matured trees. The full list of the taxonomic name of the species in Figure 4 is presented in Table S3, and the conspecific association can be used to analyze their density dependence since the tropical forest is the place for the high diversity of trees. Of 149 species, 83 species did not have either small or large individuals, suggesting that the species experienced poor regeneration. Some large individuals act as putative parent trees, even though they have failed to establish seedlings due to many factors (Seidler and Plotkin 2006; Rahman and Tsukamoto 2015). One possible factor is caused by the competition of seedlings with other plants on the forest floor, on which many life forms are found. Another rationale is that the seeds and seedlings are eaten by herbivores (Swaine et al. 1987; Houter and Pons 2014). Many studies have reported that herbivores are found in tropical rainforest since the forest provides a lot of food, for example, during germination, the dicotyledonous tree plants develop shoot from the plumule of the germinating seed (Houter and Pons 2014; Sawada et al. 2015). The distribution of individual trees in tropical forests is influenced by the ability to interact with other species. This pattern of conspecific association should be studied frequently to figure out the method of regeneration and distribution of species. Forest floor encompasses many species with different life forms as a strategy to survive and grow during the competition (Dezzotti et al. 2019). Many lianas and climbers grow fast to occupy the forest canopy and space available for sunlight. These plants suppress a certain seedling establishment (Carreño-Rocabado et al. 2012). The competition to gain sunlight, nutrition, and water is presumed as the limiting factor suffered by some species since they cannot survive below putative parent trees. Seed dispersal can be the driving force behind the spatial distribution of plants in tropical forests. Moreover, the morphological and anatomical characters of seeds and fruits also influence species regeneration and distribution. For example, small and winged seeds of tree species can spread out by falling around and away from the parent trees (Sebbenn et al. 2008; Lü and Tang 2010). However, factors such as competition, herbivory, and allelopathy have led to a clear and negative association in natural tropical forests (Padmanaba and Corlett 2014; Menezes et al. 2019). In contrast, large seeds mostly fall around the parent trees and since they survived germination, they can grow as positive conspecific associations. Therefore, the conspecific association pattern should be studied to know the natural regeneration of certain species in tropical rainforest. Figure 2. The result of Canonical Correspondence Analysis (CCA) to analyze the heterospecific associations for understory. MURDJOKO et al. – Associations of New Guinea tree 4409 Figure 3. The result of Canonical Correspondence Analysis (CCA) to analyze the heterospecific associations for the upper story Figure 4. The result of Canonical Correspondence Analysis (CCA) to analyze conspecific associations between the small and the large individuals of the same species 4410 B I OD I V E R S I TA S 21 (9): 4405-4418, September 2020 The implication of associations to ecological knowledge for sustainable management of primary forest The study of conspecific and heterospecific associations in tropical rainforest is extremely important to determine the spatial distribution pattern, especially the conspecific association. In addition, a model of natural regeneration of tree species can be described, and the result can indicate the pattern of recruitment in the population dynamics of tree species (Goodale et al. 2012; Piotto et al. 2019). Tropical rainforest is primarily dominated by flowering plants with their reproduction season is in annual period (Baker et al. 1998; Pan et al. 2013; Cámara-Leret et al. 2020). Furthermore, a suitable area for certain species to grow has resembled in the conspecific association since the study correlates small individuals with the large ones within the same species. The pattern of conspecific association can also be used to observe natural regeneration. For example, the most appropriate area to plant tree species in-situ conservation programs can be decided when artificial regeneration is necessary (Armstrong et al. 2011; Vergara-Rodrígue et al. 2017). The heterospecific association describes the pattern of growth in tropical rainforest since the forest includes the great diversity of tree species. The forest took several decades to develop, and this present study has been able to analyze the pattern of tree species association. Ecological studies on the theme of species association in tropical rainforest need to be replicated in other contexts of region, ecosystem type and forest conditions as tropical forest is very complex as made up of different life forms that interact and create vertical and horizontal structures in the climax phase of the successional process (Chazdon 2003; Brokaw and Scheiner 2012). ACKNOWLEDGEMENTS The authors thank Pegunungan Bintang District, Papua, Indonesia for the financial support, and also anonymous reviewers for improving this manuscript. REFERENCES Almeid DRA, Stark SC, Schietti J, Camargo JLC, Amazonas NT, Gorgens EB, Rosa DM, Smith MN, Valbuena R, Saleska S, Andrade A, Mesquita R, Laurance SG, Laurance WF, Lovejoy TE, Broadbent EN, Shimabukuro YE, Parker GG, Lefsky M, Silva CA, Brancalion PHS. 2019. Persistent effects of fragmentation on tropical rainforest canopy structure after 20 Yr of Isolation. Ecol Appl 29 (6): 12211235. Angelini, Alice, Corona P, Chianucci F, Portoghesi L. 2015. Structural attributes of stand overstory and light under the canopy. Ann Silvicultural Res 39 (1): 23-31. Armstrong AH. Shugart HH, Fatoyinbo TE. 2011. Characterization of community composition and forest structure in a Madagascar lowland rainforest. Trop Conserv Sci 4 (4): 428-444. Baker WJ, Coode MJE, Dransfield J, Dransfield S, Harley MM, Hoffmann P, Johns RJ. 1998. Patterns of distribution of Malesian vascular plants. Biogeogr Geol Evol SE Asia 243-258. Brokaw NVL, Scheiner SM. 2012. Species composition in gaps and structure of a tropical forest. Ecology 70 (3): 538-541. Brown S, Lugo AE, Brown S, Hall M, Gregory W, Lugo AE. 1990. Tropical secondary forests. J Trop Ecol 6 (1): 1-32. Brummitt RK. 2001. World Geographical Scheme for Recording Plant Distributions. International Working Group on Taxonomic Databases For Plant Sciences (TDWG). Hunt Institute for Botanical Documentation, Carnegie Mellon University, Pittsburgh Caceres MD, Legendre P. 2009. Associations between species and groups of sites: Indices and statistical inference. Ecology 90 (12): 3566-3574. Cámara-Leret, Rodrigo, Dennehy z. 2019. Indigenous knowledge of New Guinea’s useful plants: A review. Econ Bot 73 (3): 405-415. Cámara-Leret, Rodrigo, Frodin DG, Adema F, Anderson C, Appelhans MS, Argent G, Guerrero SA, Ashton P, Baker WJ, Barfod AS, Barrington D, Borosova R, Bramley GLC, Briggs M, Buerki S, Cahen B, Callmander MW, Cheek M, Cheng-Wei C, Conn BJ, Coode MJE, Darbyshire I, Dawson S, Dransfield J, Drinkell C, Duyfjes B, Ebihara A, Ezedin Z, Long-Fei F, Gideon O, Girmansyah D, Govaerts R, Fortune-Hopkins H, Hassemer G, Hay A, Heatubun CD, Hind DJN, Hoch P, Homot P, Hovenkamp P, Hughes M, Jebb M, Jennings L, Jimbo T, Kessler M, Kiew R, Knapp S, Lamei P, Lehnert M, Lewis GP, Linder HP, Lindsay S, Low TW, Lucas E, Mancera JP, Monro AK, Moore A, Middleton DJ, Nagamasu H, Newman MF, Lughadha EN, Melo PHA, Ohlsen DJ, Pannell CM, Parris B, Pearce L, Penneys DS, Perrie LR, Petoe P, Poulsen AD, Prance GT, Quakenbush JP, Raes N, Rodda M, Rogers ZS, Schuiteman A, Schwartsburd P, P Scotland RW, Simmons MP, Simpson DA, Stevens P, Sundue M, Testo W, Trias-Blasi A, Turner I, Utteridge T, Walsingham L, Webber BL, Wei R, Weiblen GD, Weigend M, Weston P, de Wilde W, Wilkie P, Wilmot-Dear CM, Wilson HP, Wood JRI, Li-Bing Z, van Welzen PC. 2020. New Guinea has the world’s richest island. Nature 1-5. Carreño-Rocabado G, Peña-ClaroM, Bongers F, Alarcón A, Licona JC, Poorter L. 2012. Effects of disturbance intensity on species and functional diversity in a tropical forest. J Ecol 100 (6): 1453-1463. Castilla, Antonio R, Pope N, Jha S. 2016. Positive density-dependent reproduction regulated by local Kinship and size in an understorey tropical tree. Ann Bot 117 (2): 319-329. Chazdon RL. 2003. Tropical forest recovery: Legacies of human impact and natural disturbances. Perspect Plant Ecol Evol Syst 6 (1-2): 5171. Cirimwam, L, Doumenge C, Kahindo JM, Amani C. 2019. The effect of elevation on species richness in tropical forests depends on the considered lifeform: Results from an East African Mountain Forest. Trop Ecol 60 (4): 473-484. Dezzotti A, Mortoro A, Medina A, Sbrancia R, Beltrán HA. 2019. Plant richness and life form diversity along vegetation and forest use gradients in Northwestern Patagonia of Argentina. Cerne 25 (3): 301313. Farneda FZ, Rocha R, López-Baucells A, Sampaio EM, Palmeirim JM, Bobrowiec PED, Grelle CEV, Meyer CFJ. 2018. Functional recovery of Amazonian bat assemblages following secondary forest succession. Biol Conserv 218: 192-199. Fatem, Marten S, Djitmau DA, Ungirwalu A, Wanma OA, Simbiak VI, Benu NMH, Tambing J, Murdjoko A. 2020. Species diversity, composition, and heterospecific associations of trees in three altitudinal gradients in bird’s head peninsula, Papua, Indonesia. Biodiversitas 21 (8): 3596-3605. Fernández-Lugo S, De Nascimento L, Méndez J, González-Delgado G, Gomes EPC, Otto R, Arévalo JR, Fernández-Palacios JM. 2015. Seedling survival patterns in Macaronesian laurel forest: A long-term study in Tenerife (Canary Islands). Forestry 88 (1): 121-130. Givnish TJ. 1999. On the causes of gradients in tropical tree diversity. J Ecol 87 (2): 193-210. Goodale UM, Ashton MS, Berlyn GP, Gregoire TG, Singhakumara BMP, Tennakoon KU. 2012. Disturbance and tropical pioneer species: Patterns of association across life-history stages. For Ecol Manag 277: 54-66. Gustafsson, Malin, Gustafsson L, Alloysius D, Falck J, Yap S, Karlsson A, Ilstedt U. 2016. Life-history traits predict the response to increased light among 33 tropical rainforest tree species. For Ecol Manag 362: 20-28. Houter NC, Pons TL. 2014. Gap effects on leaf traits of tropical rainforest trees differing in juvenile light requirement. Oecologia 175 (1): 3750. MURDJOKO et al. – Associations of New Guinea tree Hunter, Maria O, Keller M, Morton D, Cook B, Lefsky M, Ducey M, Saleska S, De Oliveira RS, Schietti J, Zang R. 2015. Structural dynamics of tropical moist forest gaps. PLoS ONE 10 (7): 1-19. DOI: 10.1371/journal.pone.0132144 Itoh, Akira, Yamakura T, Ogino K, Lee HS, Ashton PS. 1997. Spatial distribution patterns of two predominant emergent trees in a tropical rainforest in Sarawak, Malaysia. Plant Ecol 132 (2): 121-136. Johnson, Daniel J, Condit R, Hubbell SP, Comita LS. 2017. Abiotic niche partitioning and negative density dependence drive tree seedling survival in a tropical forest. Proc R Soc B: Biol Sci 284 (1869): 20172210. DOI: 10.1098/rspb.2017.2210. Kartikasari SN, Marshall AJ, Beehler B. 2012. Ekologi Papua. Seri Ekologi Indonesia, Jilid VI. Yayasan Obor Indonesia dan Conservation International, Jakarta. [Indonesian] Laurans M, Hérault B, Vieilledent G, Vincent G. 2014. Vertical stratification reduces competition for light in dense tropical forests. For Ecol Manag 329: 79-88. Legendre, Pierre, Fortin MJ. 1989. Spatial pattern and ecological analysis. Vegetatio 80 (2): 107-138. Liu JJ, Slik JWF. 2014. Forest fragment spatial distribution matters for tropical tree conservation. Biol Conserv 171: 99-106. Lü XT, Tang JW. 2010. Structure and composition of the understory treelets in a non-dipterocarp forest of tropical Asia. For Ecol Manag 260 (4): 565-572. Magrach, Ainhoa, Rodríguez-Pérez J, Campbell M, Laurance WF. 2014. Edge effects shape the spatial distribution of lianas and epiphytic ferns in Australian tropical rain forest fragments. Appl Veg Sci 17 (4): 754-764. Menezes GSC, Cazetta E, Dodonov P. 2019. Vegetation structure across fire edges in a neotropical rain forest. For Ecol Manag 453:117587. Montesinos-Navarro A, Estrada A, Font X, Matias MG, Meireles C, Mendoza M, Honrado JP, Prasad HD, Vicente JR, Early R. 2018. Community structure informs species geographic distributions. PLoS One 13 (5): 1-16. DOI: 10.1371/journal.pone.0197877 Montgomery RA, Chazdon RL. 2001. Forest structure, canopy architecture, and light transmittance in tropical wet forests. Ecology 82 (10): 2707- 2718. Murdjoko, Agustinus, Marsono D, Sadono R, Hadisusanto S. 2016a. Plant species composition and their conspecific association in natural tropical rainforest, South Papua. Biosaintifika J Biol Biol Educ 8(1): 33-47. Murdjoko, Agustinus, Marsono D, Sadono R, Hadisusanto S. 2016b. Tree association with Pometia and its structure in logging concession of South Papua forest. Jurnal Manajemen Hutan Tropika (Journal of Tropical Forest Management) 22 (3): 180-191. [Indonesian] Murdjoko, Agustinus, Marsono D, Sadono R, Hadisusanto S. 2017. Recovery of residual forest ecosystem as an impact of selective logging in South Papua: An ecological approach. Biotropia 24 (3): 230-245. Oksane, J, Roeland KF, Blanchet G, Legendre P, Minchin PR, O’Hara RB, Simpson GL, Solymos P, Wagner HM, Stevens HH. 2019. Package ‘Vegan.’ R Package Version 3.4.0. Padmanaba M, Corlett RT. 2014. Minimizing risks of invasive alien plant species in tropical production forest management. Forests 5 (8): 1982-1998. Pan, Yude, Birdsey RA, Phillips OL, Jackson RB. 2013. The structure, distribution, and biomass of the world’s forests. Ann Rev Ecol Evol Syst 44 (1): 593-622. Piotto D, Craven D, Montagnini F, Ashton M, Oliver C, Thomas WW. 2019. Successional, spatial, and seasonal changes in seed rain in the Atlantic forest of Southern Bahia, Brazil. PLoS ONE 14 (12): 1-15. DOI: 10.1371/journal.pone.0226474 Rahman MM, Tsukamoto J. 2015. Opposing effects of substrate quality and site factors on forest floor turnover rates: An example from the tropics. Forestry 88 (2): 190-199. Robiansyah I. 2018. Diversity and biomass of tree species in Tambrauw, West Papua, Indonesia. Biodiversitas 19 (2): 377-386. Rüger N, Berger U, Hubbell SP, Vieilledent G, Condit R. 2011. Growth strategies of tropical tree species: Disentangling light and size effects. PLoS ONE 6 (9): e25330. DOI: 10.1371/journal.pone.0025330 Sawada Yoshimi, Shin-ichiro A, Takyu M, Repin R, Nais J, Kitayama K,. 2015. Community dynamics over 14 years along gradients of geological substrate. J Trop Ecol 31 (2): 117-128. Sebbenn AM, Degen B, Azevedo VCR, Silva MB, de Lacerda AEB, Ciampi AY, Kanashiro M, da S. Carneiro F, Thompson I, Loveless. 2008 MD. Modelling the long-term impacts of selective logging on 4411 genetic diversity and demographic structure of four tropical tree species in the Amazon forest. For Ecol Manag 254 (2): 335-349. Seidler TG, Plotkin JB. 2006. Seed dispersal and spatial pattern in tropical trees. PLoS Biol 4 (11): e344. DOI: 10.1371/journal.pbio.0040344. Slik JWF, Arroyo-Rodríguez V, Aiba SI, Alvarez-Loayza P, Alves LF, Ashton P, Balvanera P, Bastian ML, Bellingham PJ, Van Den Berg E, Bernacci L, Da Conceição Bispo P, Blanc L, Böhning-Gaese K, Boeckx P, Bongers F, Boyle B, Bradford M, Brearley FQ, Hockemba MBN, Bunyavejchewin S, Matos DCL, Castillo-Santiago M, Catharino ELM, Chai SL, Chen Y, Colwell RK, Robin CL, Clark C, Clark DB, Clark DA, Culmsee H, Damas K, Dattaraja HS, Dauby G, Davidar P, DeWalt SJ, Doucet JL, Duque A, Durigan G, Eichhorn KAO, Eisenlohr PV, Eler E, Ewango C, Farwig N, Feeley KJ, Ferreira L, Field R, De Oliveira Filho AT, Fletcher C, Forshed O, Franco G, Fredriksson G, Gillespie T, Gillet JF, Amarnath G, Griffith DM, Grogan J, Gunatilleke N, Harris D, Harrison R, Hector A, Homeier J, Imai N, Itoh A, Jansen PA, Joly CA, De Jong BHJ, Kartawinata K, Kearsley E, Kelly DL, Kenfack D, Kessler M, Kitayama K, Kooyman R, Larney E, Laumonier Y, Laurance S, Laurance WF, Lawes MJ, Do Amaral IL, Letche SG, Lindsell J, Lu X, Mansor A, Marjokorpi A, Martin EH, Meilby H, Melo FPL, Metcalfe DJ, Medjibe VP, Metzger JP, Millet J, Mohandass D, Montero JC, De Morisson Valeriano M, Mugerwa B, Nagamasu H, Nilus R, Ochoa-Gaona S, Onrizal, Page P, Parolin P, Parren M, Parthasarathy N, Paudel E, Permana A, Piedade MTF, Pitman NCA, Poorter L, Poulsen AD, Poulsen J, Powers J, Prasad RC, Puyravaud JP, Razafimahaimodison JC, Reitsma J, Dos Santos JR, Spironello WR, Romero-Saltos H, Rovero F, Rozak AH, Ruokolainen K, Rutishauser E, Saiter F, Saner P, Santos BA, Santos F, Sarker SK, Satdichanh M, Schmitt CB, Schöngart J, Schulze M, Suganuma MS, Sheil D, Da Silva Pinheiro E, Sist P, Stevart T, Sukumar R, Sun IF, Sunderand T, Suresh HS, Suzuki E, Tabarelli M, Tang J, Targhetta N, Theilade I, Thomas DW, Tchouto P, Hurtado J, Valencia R, Van Valkenburg JLCH, Van Do T, Vasquez R, Verbeeck H, Adekunle V, Vieira SA, Webb CO, Whitfeld T, Wich SA, Williams J, Wittmann F, Wöll H, Yang X, Yao CYA, Yap SL, Yoneda T, Zahawi RA, Zakaria R, Zang R, De Assis RL, Luize BG, Venticinque EM. 2015. An estimate of the number of tropical tree species. Proc Nat Acad Sci USA 112 (24): 7472-7477. Slik JWF, Franklin J, Arroyo-Rodríguez V, Field R, Aguilar S, Aguirre N, Ahumada J, Aiba SI, Alves LF, Anitha K, Avella A, Mora F, Aymard GAC, Báez S, Balvanera P, Bastian ML, Bastin JF, Bellingham PJ, Van Den Berg E, Da Conceição Bispo P, Boeckx P, Boehning-Gaese K, Bongers F, Boyle F, Brambach F, Brearley FQ, Brown S, Chai SL, Chazdon RL, Chen S, Chhang P, Chuyong G, Ewango C, Coronado IM, Cristóbal-Azkarate J, Culmsee H, Damas K, Dattaraja HS, Davidar P, DeWalt SJ, Din H, Drake DR, Duque A, Durigan G, Eichhorn K, Eler ES, Enoki T, Ensslin A, Fandohan AB, Farwig N, Feeley KJ, Fischer M, Forshed O, Garcia QS, Garkoti SC, Gillespie TW, Gillet JF, Gonmadje C, Granzow-De La Cerda I, Griffith DM, Grogan J, Hakeem KR, Harris DJ, Harrison RD, Hector A, Andreas Hemp, Jürgen Homeier, M. Shah Hussain, Guillermo IbarraManríquez, I. Faridah Hanum, Nobuo Imai, Jansen PA, Joly CA, Joseph S, Kartawinata K, Kearsley E, Kelly DL, Kessler M, Killeen TJ, Kooyman RM, Laumonier Y, Laurance SG, Laurance WF, Lawes MJ, Letcher SG, Lindsell J, Lovett J, Lozada J, Lu X, Lykke AM, Bin Mahmud K, Mahayani NPD, Mansor A, Marshall AR, Martin EH, Matos DCL, Meave JA, Melo FPL, Mendoza ZHM, Metali M, Medjibe VP, Metzger JP, Metzker T, Mohandass D, Munguía-Rosas MA, Muñoz R, Nurtjahya E, Eddie Lenza De Oliveira, Onrizal, Pia Parolin, Marc Parren, N. Parthasarathy, Ekananda Paudel, Rolando Perez, Pérez-García EA, Pommer U, Poorter L, Qi L, Piedade MTF, Pinto JRR, Poulsen AD, Poulsen JR, Powers JS, Prasad RC, Puyravaud JP, Rangel O, Reitsma J, Rocha DSB, Rolim S, Rovero F, Rozak A, Ruokolainen K, Rutishauser E, Rutten G, Said MNM, Saiter FZ, Saner P, Santos B, Dos Santos JR, Sarker SK, Schmitt CB, Schoengart J, Schulze M, Sheil D, Sist P, Souza AF, Spironello WR, Sposito T, Steinmetz R, Stevart T, Suganuma MS, Sukri R, Sultana A, Sukumar R, Sunderland T, Supriyadi, Suresh HS, Suzuki E, Tabarelli M, Tang J, Tanner EVJ, Targhetta N, Theilade I, Thomas D, Timberlake J, De Morisson Valeriano M, Van Valkenburg J, Van Do T, Van Sam H, Vandermeer JH, Verbeeck H, Vetaas OR, Adekunle V, Vieira SA, Webb CO, Webb EL, Whitfeld T, Wich S, Williams J, Wiser S, Wittmann F, Yang X, Yao CYA, Yap SL, Zahawi RA, Zakaria R, Zang R. 2018. Phylogenetic classification of the world’s tropical forests. Proc Nat Acad Sci USA 115 (8): 1837-1842. 4412 B I OD I V E R S I TA S 21 (9): 4405-4418, September 2020 Steege HT, Henkel TW, Helal N, Marimon BS, Marimon-Junior BN, Huth A, Groeneveld J, Sabatier D, de Souza Coelho L, de Andrade LFD, Salomão RP, Amaral IL, de Almeida MFD, Castilho CV, Phillips OL, Guevara JE, de Jesus VCM, López DC, Magnusson WE, Wittmann F, Irume MV, Martins MP, da Silva GSR, Molino JF, Bánki OS, Piedade MTF, Pitman NCA, Mendoza AM, Ramos JF, Luize BG, de Leão NEMM, Vargas PN, Silva TSF, Venticinque EM, Manzatto AG, Reis NFC, Terborgh J, Casula KR, Coronado ENH, Montero JC, Feldpausch TR, Duque A, Costa FRC, Arboleda NC, Schöngart J, Killeen TJ, Vasquez R, Mostacedo B, Demarchi LO, Assis RL, Baraloto C, Engel J, Petronelli P, Castellanos P, de Medeiros MB, Quaresma A, Simon MF, Andrade A, Camargo JL, Laurance SGW, Laurance WF, Rincón LM, Schietti J, Sousa TR, de Sousa FE, Lopes MA, Magalhães JLL, Nascimento HEM, de Queiroz HL, Aymard CGA, Brienen R, Revilla JDC, Vieira ICG, Cintra BBL, Stevenson PR, Feitosa YO, Duivenvoorden JF, Mogollón HF, Araujo-Murakami A, Ferreira LV, Lozada JR, Comiskey JA, de Toledo JJ, Damasco G, Dávila N, Draper F, García-Villacorta R, Lopes A, Vicentini A, Alonso A, Dallmeier F, Gomes VHF, Lloyd J, Neill D, de Aguiar DPP, Arroyo L, Carvalho FA, de Souza FC, do Amaral DD, Feeley KJ, Gribel R, Pansonato MP, Barlow J, Berenguer E, Ferreira J, Fine PVA, Guedes MCA, Jimenez EM, Licona JC, Mora MCP, Villa B, Cerón C, Maas P, Silveira M, Stropp J, Thomas R, Baker TR, Daly D, Dexter KG, HuamantupaChuquimaco I, Milliken W, Pennington T, Paredes MR, Fuentes A, Klitgaard B, Pena JJM, Peres CA, Silman MR, Tello JS, Chave J, Valverde FC, Di Fiore A, Hilário RR, Phillips JF, Rivas-Torres G, van Andel TR, von Hildebrand P, Noronha JC, Barbosa EM, Barbosa FR, de Matos BLC, de Sá Carpanedo R, Doza HPD, Fonty E, Zárate RG, Gonzales T, Gonzales GPG, Hoffman B, Junqueira AB, Malhi Y, de Andrade MIP, Pinto LFM, Prieto A, de Jesus RD, Rudas A, Ruschel AR, Silva N, Vela CIA, Vos VA, Zent EL, Zent S, Albuquerque BW, Cano A, Márquez YAC, Correa DF, Costa JBP, Flores BM, Galbraith D, Holmgren M, Kalamandeen M, Nascimento MT, Oliveira AA, Ramirez-Angulo H, Rocha M, Scudeller VV, Sierra R, Tirado M, Medina MNU, van der Heijden G, Torre EV, Vriesendorp C, Wang O, Young KR, Reategui MAA, Baider C, Balslev H, Cárdenas S, Casas LF, Farfan-Rios W, Ferreira C, Linares-Palomino R, Mendoza C, Mesones I, Torres-Lezama A, Giraldo LEU, Villarroel D, Zagt R, Alexiades MN, de Oliveira EA, Garcia-Cabrera K, Hernandez L, Cuenca WP, Pansini S, Pauletto D, Arevalo FR, Sampaio AF, Sandoval EHV, Gamarra LV, Levesley A, Pickavance G, Melgaço K. 2019. Rarity of monodominance in hyperdiverse Amazonian Forests. Sci Rep 9 (1): 1-15. Swaine MD, Lieberman D, Putz FE. 1987. The dynamics of tree populations in tronical forest: A review. J Trop Ecol 3 (4): 359-366. Ter Braak CJF. 1986. Canonical correspondence analysis: A new eigenvector technique for multivariate direct gradient analysis. Ecology 67 (5): 1167-1179. Thomas SC, Baltzer JL. 2002. Tropical Forests. Encyclopedia of Life Sciences 1-8. Vergara-Rodrígue D, Mathieu G, Samain MS, Armenta-Montero S, Krömer T. 2017. Diversity, distribution, and conservation status of Peperomia (Piperaceae) in the State of Veracruz, Mexico. Trop Conserv Sci 10 (44): 1-18. Vitousek, Peter M. 1984. Litterfall, nutrient cycling, and nutrient limitation in tropical forests. Ecology 65 (1): 285-298. Wang, Hongxiang, Peng H, Hui G, Hu Y, Zhao Z. 2018. Large trees are surrounded by more heterospecific neighboring trees in Korean pine broad-leaved natural forests. Sci Rep 8 (1): 1-11. Wright SJ, Muller-Landau HC. 2006. The uncertain future of tropical forest species. Biotropica 38 (4): 443-445. Yamamoto, Shin-Ichi. 2000. Forest gap dynamics and tree regeneration. J For Res 5 (4): 223-229. Zhu, Yan, Comita LS, Hubbell SP, Keping Ma. 2015. Conspecific and phylogenetic density-dependent survival differs across life stages in a tropical forest. J Ecol 103 (4): 957-966. MURDJOKO et al. – Associations of New Guinea tree 4413 Table S1. Species name of heterospecific associations for understory for Figure 2 No. Code Species 1 2 3 4 5 6 7 8 9 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 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 Kiba_co Rhus_la Dios_pi Lits_le Maca_gi Maca_ta Seme_pa Ster_sh Case_ca Xant_no Teij_bo Flin_pi Case_sp Hapl_ce Myri_en Octa_in Piso_lo Wend_sp Timo_ca Prun_ja Hapl_fl Anti_de Buch_ar Cryp_pa Gmel_se Garc_pi Para_ve Knem_in Case_mo Half_ke Syzy_ve Ficu_ro Heri_sy Cerb_fl Myri_gl Dryp_gl Phal_ma Cana_ri Lits_ti Timo_ti Homa_fo Endo_me Pome_pi Kiba_bu Drac_da Goni_gi Nauc_or Beil_mo Cara_br Lits_sp Pime_am Medu_la Myri_fa Gono_li Lith_ru Hope_pa Dill_pa Mast_pa Pome_ac Kiba_el Clei_pa Ints_pa Galb_be Kibara coriacea (Blume) Hook. f. & A. Thomps. Rhus lamprocarpa Merr. & L.M.Perry Diospyros pilosanthera Blanco Litsea ledermannii Teschner Macaranga gigantea (Rchb.f. & Zoll.) Müll.Arg. Macaranga tanarius (L.) Müll.Arg. Semecarpus papuana Lauterb. Sterculia shillinglawii F.Muell. Casearia carrii Sleumer Wendlandia sp Teijsmanniodendron bogoriense Koord. Flindersia pimenteliana F.Muell. Casearia sp Haplolobus celebicus H.J.Lam Myristica ensifolia J.Sinclair Octamyrtus insignis Diels Pisonia longirostris Teijsm. & Binn. Wendlandia sp Timonius carii S.P.Darwin Prunus javanica (Teijsm. & Binn.) Miq. Haplolobus floribundus (K.Schum.) H.J.Lam Alstonia spectabilis R.Br. Buchanania arborescens (Blume) Blume Cryptocarya palmerensis C.K.Allen Gmelina sessilis C.T.White & W.D.Francis ex Lane-Poole Garcinia picrorhiza Miq. Parastemon versteeghii Merr. & L.M.Perry Knema intermedia Warb. Casearia monticola Sleumer Halfordia kendack Guillaumin Syzygium versteegii (Lauterb.) Merr. & L.M.Perry Ficus robusta Corner Heritiera sylvatica S.Vidal Cerbera floribunda K.Schum. Myristica globosa Warb. Drypetes globosa (Merr.) Pax & K.Hoffm. Phaleria macrocarpa (Scheff.) Boerl. Canarium rigidum (Blume) Zipp. ex Miq. Litsea timoriana Span. Timonius timon (Spreng.) Merr. Heritiera sylvatica S.Vidal Endospermum medullosum L.S.Sm. Pometia pinnata J.R.Forst. & G.Forst. Kibara bullata Philipson Dracontomelon dao (Blanco) Merr. & Rolfe Goniothalamus giganteus Hook.f. & Thomson Nauclea orientalis (L.) L. Beilschmiedia morobensis Kosterm. Carallia brachiata (Lour.) Merr. Litsea sp Pimelodendron amboinicum Hassk. Medusanthera laxiflora (Miers) R.A.Howard Myristica fatua Houtt. Gonocaryum litorale (Blume) Sleumer Lithocarpus rufovillosus (Markgr.) Rehder Hopea papuana Diels Dillenia papuana Martelli Mastixiodendron pachyclados (K.Schum.) Melch. Pometia acuminata Radlk. Kibara elongata A.C.Sm. Cleistanthus papuanus (Lauterb.) Jabl. Intsia palembanica Miq. Galbulimima belgraveana (F.Muell.) Sprague Group 1 + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + Group 2 Group 3 B I OD I V E R S I TA S 21 (9): 4405-4418, September 2020 4414 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 Term_co Giro_ne Mani_pl Hope_ce Meli_el Garc_sp Pala_lo Camp_br Ster_ma Harp_ca Hors_la Arch_pa Chry_pa Fagr_ra Klei_ho Endi_ru Tris_ma Cory_la Cryp_sp Tabe_au Mall_sp Deca_pa Agla_sp Rapa_te Calo_ca Xant_pa Hapl_la Alst_sp Dios_sp Elae_an Rypa_ja Rhod_ci Myri_gi Anti_to Calo_in Para_pr Siph_ce Siph_sp Maas_gl Term_ka Spat_ja Dyso_mo Plan_ke Ficu_sp Hors_pa Terminalia copelandi Elmer Gironniera nervosa Planch. Maniltoa plurijuga Merr. & L.M.Perry Hopea celtidifolia Kosterm. Melicope elleryana (F. Muell.) T.G. Hartley Garcinia sp Palaquium lobbianum Burck Campnosperma brevipetiolatum Volkens Sterculia macrophylla Vent. Harpullia carrii Leenh. Horsfieldia laevigata Warb. Archidendron parviflorum Pulle Chrysophyllum papuanicum (Pierre ex Dubard) Royen Fagraea racemosa Jack Kleinhovia hospita L. Endiandra rubescens (Blume) Miq. Tristaniopsis macrosperma (F.Muell.) Peter G.Wilson & J.T.Waterh. Corynocarpus laevigatus J.R.Forst. & G.Forst. Cryptocarya sp Tabernaemontana aurantiaca Gaudich. Mallotus sp Decaspermum parviflorum (Lam.) A.J.Scott Aglaia spectabilis (Miq.) S.S.Jain & S.Bennet Rapanea tempanpan P.Royen Calophyllum caudatum Kaneh. & Hatus. Xanthophyllum papuanum Whitmore ex Meijden Haplolobus lanceolatus H.J.Lam ex Leenh. Alstonia spectabilis R.Br. Diospyros sp Elaeocarpus angustifolius Blume Ryparosa javanica Koord. & Valeton Rhodamnia cinerea Jack Myristica gigantea King Antiaris toxicaria Lesch. Calophyllum inophyllum L. Pararchidendron pruinosum (Benth.) I.C.Nielsen Siphonodon celastrineus Griff. Siphonodon sp Maasia glauca (Hassk.) Mols, Kessler & Rogstad Terminalia kaernbacchii Warb. Spathiostemon javensis Blume Dysoxylum mollissimum Blume Planchonella keyensis H.J.Lam Ficus sp Horsfieldia parviflora (Roxb.) J.Sinclair + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + MURDJOKO et al. – Associations of New Guinea tree 4415 Table S2. Species name of heterospecific associations for upper story Figure 3 No. Code Species 1 2 3 4 5 6 7 8 9 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 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 Hors_ir Garc_la Alst_sc Endi_vi Sloa_pu Galb_be Pome_ac Chis_ce Dyso_mo Endo_me Pime_am Gono_li Stre_el Homa_fo Gnet_gn Homa_no Cory_la Drac_da Cana_od Pter_be Pala_lo Cana_in Cara_br Timo_ca Hors_sy Maas_su Hope_pa Hope_ce Rhus_ta Acti_ni Dill_pa Medu_la Teij_bo Tris_ma Call_lo Comm_ba Dios_pi Knem_in Dryp_gl Cryp_pa Meli_el Lits_ti Siph_ce Siph_sp Vite_pi Poly_no Pome_pi Agla_ar Acro_sp Gmel_se Mani_br Prun_ar Camp_br Hors_la Cana_hi Deca_pa Calo_in Heri_sy Clei_pa Elae_an Gymn_fa Grew_er Xant_no Horsfieldia irya (Gaertn.) Warb. Garcinia latissima Miq. Alstonia scholaris (L.) R. Br. Endiandra virens F.Muell. Sloanea pullei O.C.Schmidt ex A.C.Sm. Galbulimima belgraveana (F.Muell.) Sprague Pometia acuminata Radlk. Chisocheton ceramicus Miq. Dysoxylum mollissimum Blume Endospermum medullosum L.S.Sm. Pimelodendron amboinicum Hassk. Gonocaryum littorale (Blume) Sleumer Streblus elongatus (Miq.) Corner Heritiera sylvatica S.Vidal Gnetum gnemon L. Homalanthus novoguineensis (Warb.) K.Schum. Corynocarpus laevigatus J.R.Forst. & G.Forst. Dracontomelon dao (Blanco) Merr. & Rolfe Canarium indicum L. Pterocymbium beccarii K.Schum. Palaquium lobbianum Burck Canarium indicum L. Carallia brachiata (Lour.) Merr. Timonius carii S.P.Darwin Horsfieldia sylvestris Warb. Maasia sumatrana (Miq.) Mols, Kessler & Rogstad Hopea papuana Diels Hopea celtidifolia Kosterm. Rhus taitensis Guill. Actinodaphne nitida Teschner Dillenia papuana Martelli Medusanthera laxiflora (Miers) R.A.Howard Teijsmanniodendron bogoriense Koord. Tristaniopsis macrosperma (F.Muell.) Peter G.Wilson & J.T.Waterh. Callicarpa longifolia Lam. Commersonia bartramia (L.) Merr. Diospyros pilosanthera Blanco Knema intermedia Warb. Drypetes globosa (Merr.) Pax & K.Hoffm. Cryptocarya palmerensis C.K.Allen Melicope elleryana (F. Muell.) T.G. Hartley Litsea timoriana Span. Siphonodon celastrineus Griff. Siphonodon sp Vitex pinnata L. Polyscias nodosa (Blume) Seem. Pometia pinnata J.R.Forst. & G.Forst. Aglaia argentea Blume Acronychia sp Gmelina sessilis C.T.White & W.D.Francis ex Lane-Poole Maniltoa browneoides Harms Prunus arborea (Blume) Kalkman Campnosperma brevipetiolatum Volkens Horsfieldia laevigata Warb. Campnosperma brevipetiolatum Volkens Decaspermum parviflorum (Lam.) A.J.Scott Calophyllum inophyllum L. Heritiera sylvatica S.Vidal Cleistanthus papuanus (Lauterb.) Jabl. Elaeocarpus angustifolius Blume Gymnacranthera farquhariana (Hook.f. & Thomson) Warb. Grewia eriocarpa Juss. Wendlandia sp Group 1 Group 2 + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + Group 3 Group 4 B I OD I V E R S I TA S 21 (9): 4405-4418, September 2020 4416 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 Rhod_ci Arto_al Para_pr Plan_ke Dios_pa Ochr_gl Myri_fa Ster_sh Syzy_sp2 Syzy_sp3 Xant_pa Euca_pa Flin_pi Hapl_fl Lits_fi Term_co Calo_ca Coch_gi Buch_ar Fagr_el Prun_ja Endi_ru Cryp_sp Rhodamnia cinerea Jack Artocarpus altilis (Parkinson ex F.A.Zorn) Fosberg Pararchidendron pruinosum (Benth.) I.C.Nielsen Planchonella keyensis H.J.Lam Diospyros papuana Valeton ex Bakh. Ochrosia glomerata (Blume) F.Muell. Myristica fatua Houtt. Sterculia shillinglawii F.Muell. Syzygium sp2 Syzygium sp3 Xanthophyllum papuanum Whitmore ex Meijden Eucalyptopsis papuana C.T.White Flindersia pimenteliana F.Muell. Haplolobus floribundus (K.Schum.) H.J.Lam Litsea firma (Blume) Hook.f. Terminalia copelandi Elmer Calophyllum caudatum Kaneh. & Hatus. Cochlospermum gillivraei Benth. Buchanania arborescens (Blume) Blume Fagraea elliptica Roxb. Prunus javanica (Teijsm. & Binn.) Miq. Endiandra rubescens (Blume) Miq. Cryptocarya sp + + + + + + + + + + + + + + + + + + + + + + + MURDJOKO et al. – Associations of New Guinea tree 4417 Table S3. Species name of conspecific associations Figure 4. The S stands for small individuals and L symbolizes large individuals. No. 1 2 3 4 5 6 7 8 9 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 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 Code Agla_ar Agla_ar Buch_ar Buch_ar Calo_ca Calo_ca Calo_in Calo_in Camp_br Camp_br Cana_hi Cana_hi Cana_in Cana_in Cara_br Cara_br Clei_pa Clei_pa Cory_la Cory_la Cryp_pa Cryp_pa Cryp_sp Cryp_sp Deca_pa Deca_pa Dill_pa Dill_pa Dios_pi Dios_pi Drac_da Drac_da Dryp_gl Dryp_gl Dyso_mo Dyso_mo Elae_an Elae_an Endi_ru Endi_ru Endo_me Endo_me Flin_pi Flin_pi Galb_be Galb_be Garc_la Garc_la Giro_ne Giro_ne Gmel_se Gmel_se Gnet_gn Gnet_gn Gono_li Gono_li Gymn_fa Gymn_fa Hapl_fl Hapl_fl Heri_sy Heri_sy Homa_fo Homa_fo Hope_ce Hope_ce Hope_no _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L Species Aglaia argentea Blume Aglaia argentea Blume Buchanania arborescens (Blume) Blume Buchanania arborescens (Blume) Blume Calophyllum caudatum Kaneh. & Hatus. Calophyllum caudatum Kaneh. & Hatus. Calophyllum inophyllum L. Calophyllum inophyllum L. Campnosperma brevipetiolatum Volkens Campnosperma brevipetiolatum Volkens Canarium hirsutum Willd. Canarium hirsutum Willd. Canarium indicum L. Canarium indicum L. Carallia brachiata (Lour.) Merr. Carallia brachiata (Lour.) Merr. Cleistanthus papuanus (Lauterb.) Jabl. Cleistanthus papuanus (Lauterb.) Jabl. Corynocarpus laevigatus J.R.Forst. & G.Forst. Corynocarpus laevigatus J.R.Forst. & G.Forst. Cryptocarya palmerensis C.K.Allen Cryptocarya palmerensis C.K.Allen Cryptocarya sp Cryptocarya sp Decaspermum parviflorum (Lam.) A.J.Scott Decaspermum parviflorum (Lam.) A.J.Scott Dillenia papuana Martelli Dillenia papuana Martelli Diospyros pilosanthera Blanco Diospyros pilosanthera Blanco Dracontomelon dao (Blanco) Merr. & Rolfe Dracontomelon dao (Blanco) Merr. & Rolfe Drypetes globosa (Merr.) Pax & K.Hoffm. Drypetes globosa (Merr.) Pax & K.Hoffm. Dysoxylum mollissimum Blume Dysoxylum mollissimum Blume Elaeocarpus angustifolius Blume Elaeocarpus angustifolius Blume Endiandra rubescens (Blume) Miq. Endiandra rubescens (Blume) Miq. Endospermum medullosum L.S.Sm. Endospermum medullosum L.S.Sm. Flindersia pimenteliana F.Muell. Flindersia pimenteliana F.Muell. Galbulimima belgraveana (F.Muell.) Sprague Galbulimima belgraveana (F.Muell.) Sprague Garcinia latissima Miq. Garcinia latissima Miq. Gironniera nervosa Planch. Gironniera nervosa Planch. Gmelina sessilis C.T.White & W.D.Francis ex Lane-Poole Gmelina sessilis C.T.White & W.D.Francis ex Lane-Poole Gnetum gnemon L. Gnetum gnemon L. Gonocaryum littorale (Blume) Sleumer Gonocaryum littorale (Blume) Sleumer Gymnacranthera farquhariana (Hook.f. & Thomson) Warb. Gymnacranthera farquhariana (Hook.f. & Thomson) Warb. Haplolobus floribundus (K.Schum.) H.J.Lam Haplolobus floribundus (K.Schum.) H.J.Lam Heritiera sylvatica S.Vidal Heritiera sylvatica S.Vidal Homalium foetidum Benth. Homalium foetidum Benth. Hopea celtidifolia Kosterm. Hopea celtidifolia Kosterm. Hopea novoguineensis Slooten B I OD I V E R S I TA S 21 (9): 4405-4418, September 2020 4418 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 Hope_no Hope_pa Hope_pa Hors_la Hors_la Ints_pa Ints_pa Knem_in Knem_in Lith_ru Lith_ru Lits_ti Lits_ti Mani_br Mani_br Medu_la Medu_la Meli_el Meli_el Myri_fa Myri_fa Pala_lo Pala_lo Para_pr Para_pr Para_ve Para_ve Pime_am Pime_am Plan_ke Plan_ke Pome_ac Pome_ac Pome_pi Pome_pi Prun_ar Prun_ar Prun_ja Prun_ja Rhod_ci Rhod_ci Siph_ce Siph_ce Siph_sp Siph_sp Sloa_pu Sloa_pu Ster_sh Ster_sh Syzy_sp1 Syzy_sp1 Teij_bo Teij_bo Term_co Term_co Timo_ca Timo_ca Tris_ma Tris_ma Vati_ra Vati_ra Xant_pa Xant_pa Xant_no Xant_no _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S _L _S Hopea novoguineensis Slooten Hopea papuana Diels Hopea papuana Diels Horsfieldia laevigata Warb. Horsfieldia laevigata Warb. Intsia palembanica Miq. Intsia palembanica Miq. Knema intermedia Warb. Knema intermedia Warb. Lithocarpus rufovillosus (Markgr.) Rehder Lithocarpus rufovillosus (Markgr.) Rehder Litsea timoriana Span. Litsea timoriana Span. Maniltoa browneoides Harms Maniltoa browneoides Harms Medusanthera laxiflora (Miers) R.A.Howard Medusanthera laxiflora (Miers) R.A.Howard Melicope elleryana (F. Muell.) T.G. Hartley Melicope elleryana (F. Muell.) T.G. Hartley Myristica fatua Houtt. Myristica fatua Houtt. Palaquium lobbianum Burck Palaquium lobbianum Burck Pararchidendron pruinosum (Benth.) I.C.Nielsen Pararchidendron pruinosum (Benth.) I.C.Nielsen Parastemon versteeghii Merr. & L.M.Perry Parastemon versteeghii Merr. & L.M.Perry Pimelodendron amboinicum Hassk. Pimelodendron amboinicum Hassk. Planchonella keyensis H.J.Lam Planchonella keyensis H.J.Lam Pometia acuminata Radlk. Pometia acuminata Radlk. Pometia pinnata J.R.Forst. & G.Forst. Pometia pinnata J.R.Forst. & G.Forst. Prunus arborea (Blume) Kalkman Prunus arborea (Blume) Kalkman Prunus javanica (Teijsm. & Binn.) Miq. Prunus javanica (Teijsm. & Binn.) Miq. Rhodamnia cinerea Jack Rhodamnia cinerea Jack Siphonodon celastrineus Griff. Siphonodon celastrineus Griff. Siphonodon sp Siphonodon sp Sloanea pullei O.C.Schmidt ex A.C.Sm. Sloanea pullei O.C.Schmidt ex A.C.Sm. Sterculia shillinglawii F.Muell. Sterculia shillinglawii F.Muell. Syzygium sp1 Syzygium sp1 Teijsmanniodendron bogoriense Koord. Teijsmanniodendron bogoriense Koord. Terminalia copelandi Elmer Terminalia copelandi Elmer Timonius carii S.P.Darwin Timonius carii S.P.Darwin Tristaniopsis macrosperma (F.Muell.) Peter G.Wilson & J.T.Waterh. Tristaniopsis macrosperma (F.Muell.) Peter G.Wilson & J.T.Waterh. Vatica rassak Blume Vatica rassak Blume Xanthophyllum papuanum Whitmore ex Meijden Xanthophyllum papuanum Whitmore ex Meijden Xanthostemon novaguineensis Valeton Xanthostemon novaguineensis Valeton