BIODIVERSITAS ISSN: 1412-033X Volume 21, Number 7, July 2020 E-ISSN: 2085-4722 Pages: 3025-3033 DOI: 10.13057/biodiv/d210720 Vegetation structure and floristic composition of tree species in the habitat of Scaphium macropodum in Gunung Leuser National Park, Sumatra, Indonesia ARIDA SUSILOWATI1,, DENI ELFIATI1, HENTI HENDALSTUTI RACHMAT2, KUSUMADEWI SRI YULITA3, ADI NURUL HADI4, YOSIE SYADZA KUSUMA5, SRI ANJELI LUMBAN BATU1 1Faculty of Forestry, Universitas Sumatera Utara. Jl. Tri Dharma Ujung No. 1, Kampus USU, Medan 20155, North Sumatra, Indonesia. Tel./fax.:+62-61-820-1920, email: [email protected]; [email protected] 2Forest Research and Development Center, Ministry of Environment and Forestry. Jl. Raya Gunung Batu, Bogor 16118, West Java, Indonesia 3Research Center for Biology, Indonesian Institutes of Sciences. Jl. Raya Bogo Km. 46, Cibinong, Bogor 16911. West Java, Indonesia 4Gunung Leuser National Park, Ministry of Environment and Forestry. Jl. Selamat No. 137, Medan 20219, North Sumatra, Indonesia 5Tropical Silviculture Program, School of Graduates, Institut Pertanian Bogor. Jl. Raya Dramaga, Bogor 16680, West Java, Indonesia Manuscript received: 2 June 2020. Revision accepted: 12 June 2020. Abstract. Susilowati A, Elfiati D, Rachmat HH, Yulita KS, Hadi AN, Kusuma YS, Batu SAL. 2020. Vegetation structure and floristic composition of tree species in the habitat of Scaphium macropodum in Gunung Leuser National Park, Sumatra, Indonesia. Biodiversitas 21: 3025-3033. Scaphium macropodum (Miq.) Beumee Ex K Heyne is a member of Malvaceae tree species and globally recognized as malva nut and locally known as ‘kembang semangkok’, ‘tempayang’, ‘merpayang’ or ‘kepayang’. The nut of S. macropodum has many benefits for medicinal purposes, yet destructive extraction of this tree species has led them to extinction. Among its natural distribution in Indonesia, North Sumatra Province, Indonesia is known as its original range, but there is limited information about the existence of this species. This study aimed to determine the vegetation structure of some tree species in the habitat of S. macropodum in Sikundur, Gunung Leuser National Park, Sumatra, Indonesia. Purposive sampling technique was employed by creating line transect at some forest areas where the population of S. macropodum is known to grow naturally. Four line transects with each transect consisting of five plots with nested plots within were established to record data at four growth stages, resulting in 80 plots in total. The results showed that the Important Value Index (IVI) of S. macropodum within the floristic community at the studied area was 21.98, 13.85, 27.30, and 39.60 for tree, pole, sapling, and seedlings stages, respectively. The Shannon-Wiener Diversity Index (H) were 3.80, 3.70, 3.06 and 2.45, Index of evenness (E) are 0.94, 0.92, 0.86, 0.77 and the Index of Richness (R) are 11.76, 10.73, 6.59, 4.10 for tree, pole, sapling, and seedlings stages. This result suggests that the natural population of S. macropodum in Sikundur forest was still in good condition at all stages from tree to seedling. Keywords: Diversity, growth stage, kembang semangkok, species, structure vegetation INTRODUCTION Red-list (World Conservation Monitoring Center 1998). According to Lim (2012), S. macropodum is well Scaphium is a member of tree genus with large canopy known to have medicinal properties. Both in vitro and in with height that can reach up to 40 m and diameter at breast vivo studies demonstrate that this species exhibits a variety height is usually 10-40 cm (Wilkie 2009). There are eight of pharmacological activities, including antihypertensive, species from Scaphium genera distributed in Southeast antimicrobial, analgesic, anti-inflammatory, antipyretic, Asia region from Burma, through Thailand, Cambodia, weight-losing and laxative (Ai et al. 2012; Li 2015; Ogale Malaysia, Singapore, Sumatra, and Bangka to Borneo et al. 2015; Dhange et al. 2015;). In Vietnam, the fruits of (Yamada et al. 2000). One of Scaphium species that grows S. macropodum are widely used for tonic and medicinal naturally in Indonesia is Scaphium macropodum (Miq.) beverages (Huy et al. 2012). When its nuts soaked in water Beumee Ex K Heyne (Yamada et al. 1999). S. it will produce large amounts of gelatin, which is used as a macropodum is distributed in Myanmar, Cambodia, Laos, medicine to cure intestinal infections, diarrhea, sore throat, Vietnam, Thailand, Peninsular Malaysia, Sumatra, and asthma, dysentery, fever, cough, inflammation, and urinary Borneo (Lim 2012). S. macropodum, locally known as tract diseases. Some people drink malva nut juice for ‘kembang semangkok’, ‘tempayang’, ‘merpayang’, dieting purposes because it has cool feels and can break ‘kepayang’ or malva nut, is a wild tree species and is fever. In Java, malva nut is mixed with cinnamon and basil known as one of important non-timber forest products that to treat thrush and cough. Mixing malva nut with bitter aloe supports the livelihoods of community living around forest and Vitex pteropod seeds is commonly used to cure (Bann 1997). The high demand for its seeds for traditional dysentery (Phonsena and Wilkie 2008). and pharmacological uses together with the lack of Among S. macropodum natural distribution in Sumatra, cultivation efforts, has reduced the species population, Batangtoru, and Gunung Leuser National Park (GLNP) are putting them as least concern category according to IUCN found as the natural habitat of the species (Sambas and 3026 BIODIVERSI TAS 21 (7): 3025-3033, July 2020 Siregar 2017). GNLP is a conservation area where MATERIALS AND METHODS exploitation and land-use change are strictly prohibited by laws, however, there are some illegal activities performed Study period and location by community, for example, timber cutting for construction The data collection and soil sampling activities were materials and fuelwood collection. Due to these activities, carried out at the Sikundur monitoring station in Gunung the forest ecosystem in GLNP has been experiencing Leuser National Park (Figure 1) on May-August 2019. The decreasing number in tree species and stands, resulting Sikundur monitoring station is located in Besitang changes in species composition. Similar trends may occur Subdistrict, Langkat District, North Sumatra Province, to S. macropodum population which can change their Indonesia with an area of ± 500 ha. Geographically, it is sustainability in the future. located at N 03o56'20.9 and E 098o03'44.9" with an altitude Analysis on vegetation composition and structure in a between 30-100 meters above sea level. The topographical habitat enables to reveal the status and quality of a forest conditions at Sikundur Monitoring station of GLNP are community by quantifying the existence of tree species at generally flat, with few areas are undulating and mild. The each growing stage and also observed the threat and geological and soil consist of igneous and volcanic rock possible conservation effort to conduct in the future materials with brown to brownish podzolic soil (Sumatran (Rachmat et al. 2018; Susilowati et al. 2019). Vegetation Orang Utan Conservation Programme 2015). structure is also highly determined by habitat characteristics, species diversity, and regeneration status of a species Data collection (Dutta and Devi 2013). Vegetation studies are important in The data for vegetation analysis and floristic order to provide basic data to formulate conservation composition were collected by applying purposive strategies and species management, especially the species sampling technique based on guided information and that have high levels of vulnerability. Thus, this study is reports on the occurrence of S. macropodum in certain sites conducted to determine the vegetation structure of some of the forest (Jumawan 2015; Rachmat et al. 2018). Species tree species in the habitat of S. macropodum in Gunung identification was carried out by employing a botanist. Few Leuser National Park, Sumatra, Indonesia. This information is species unable to identify in the field were taken its important, since the data on population and distribution of specimens to be identified later in the herbarium. S. macropodum in its natural distribution of North Sumatra is still limited despite their widely known benefits to support the sustainability of this species in the future. Figure 1. The study location at Sikundur monitoring station in Gunung Leuser National Park, Sumatra, Indonesia SUSILOWATI et al. – Scaphium macropodum habitat in Gunung Leuser National Park, Indonesia 3027 There were total of four transects established at the Importance Value Index (IVI) (%) studied sites where S. macropodum grow, with five IVI can be calculated using the formula: plots/quadrats for each transect. A line transect was For tree species, IVI = RD + RF + RBA established starting from the forest edge with the minimum For seedlings and saplings, IVI = RD + RF length of transect was 200 m. In each transect, nested plots were established with the size of 2x2 m2, 5x5 m2, 10x10 Species diversity m2, and 20x20 m2 to record all necessary data for seedling, Various diversity measures are calculated by using sapling, pole, and tree stages, respectively. The observed Shannon-Wiener index (Hʹ), Margalef index (R), and variables for each stage were as follows: (i) Seedling stage Evenness (E). The species diversity is determined by using (germinated seeds to < 1.5 m in height): species, number of Shannon-Wiener and is formulated as follows: individuals of each species; (ii) Sapling stage (height >1.5 m to diameter at breast height (dbh) < 10 cm): species, H’ = ∑ pi ln pi; number of individuals of each species; (iii) Pole stage (10 cm < dbh < 20 cm): species, dbh, height; (iv) Tree stage Where, pi is the proportion of individuals of ith species (dbh >20 cm): species, dbh, height. These data were then and individuals of all species in a stand. According to used to calculate relative density, frequency, abundance, Indriani (2009), the Shannon-Weiner diversity index value and dominance of the tree species; and from those values, criteria can be categorized as low (H '<1), moderate (H' 1- the Importance Value Index (IVI) was calculated.