A tree species inventory in a one-hectare plot at the Batang Gadis National Park, North Sumatra, Indonesia

Abstract

Reinwardtia 12 (2): 145 -157. The results of the inventory of trees with DBH ≥ 10 cm shows that 184 species in 41 families, represented by 583 individuals with the total basal areas of 40.56 m² occurred in the one-hectare plot sampled. Together with the saplings and shrubs the number of species was 240 belonging to 47 families. The forest is richer in tree species than other lowland forests in North Sumatra, but poorer than those in Borneo and the Malay Peninsula. Dipterocarps constituted 18.42 % of total species with basal area of 18.99 m² or 46.82 % of the total basal area in the plot. The most prominent species was Shorea gibbosa. Hopea nigra, reported to be rare in Bangka and Belitung, occurred here as one of the ten leading species. The species-area curve shows that a considerable number of additional species was encountered more or less steadily up to one hectare and there was no indication of levelling off. A simulated profile diagram shows the forest may be stratified into five layers: (1) emergent layer, (2) upper canopy, (3) middle canopy, (4) lower canopy and (5) ground canopy. Dipterocarps were leading species in the emergent layer, upper canopy and middle canopy. Only 82 species were regenerating as represented by their presence in the sapling stage ranging from 5 to 50 plants/hectare. Macaranga lowii King ex Hook. f. dominated the section which seemed to be previously occupied by gaps.

Tree Species Diversity in the Lowland Forest of the Core Zone of the Bukit Duabelas National Park, Jambi, Indonesia

“…Current knowledge of the ecology, floristic, structure and species richness of the lowland dipterocarp forests is mainly based on scattered studies carried out in different parts of Sumatra, mainly in national parks and other protected areas, such as the Batang Gadis National Park (Kartawinata et al, 2004), Rimbo Panti Nature Reserve (Yusuf et al, 2005), Gunung Leuser National Park (Abdulhadi, 1991;Samsoedin & Heriyanto, 2010), Berbak National Park (Silvius et al, 1984), Bukit Tigapuluh National Park (Polosakan, 2001), Hutan Danau Bangko (Polosakan, 2011), Kerinci Seblat National Park (Gillison et al, 1996), Tesso Nilo National Park (Gillison, 2001), Harapan Tropical Rainforest (Mansur et al, 2010) and Imbo Mengkadai customary forest (Elviqar, 2013;Hermawan, 2013). Such detailed studies in the Bukit Duabelas National Park (BDNP) in Jambi are still meager.…”

Phytosociology of a Lower Montane Forest on Mt. Batulanteh, Sumbawa, Indonesia

“…In general the topography of the study site was undulating to hilly with slopes of 25 0 -40 0 . The soils were dominated by lithosols and brown Mediteranian, less fertile, thin solum (< 90cm) and sensitive to erosion (Julmansyah, 2014).…”

“…Within each quadrat all trees with DBH (Diameter at Breast Height) ≥ 5 cm were identified, their diameters were measured and bole heights and total tree heights were estimated by comparing with the heights of measured selected trees which were used as references. A simulated forest profile diagram for each plot was constructed using the method of Kartawinata et al (2004) by plotting in a linear row the data on tree heights and tree numbers reflecting the sequence of field recording.…”

“…and its surrounding areas in the Sumbawa Besar District, West Nusa Tenggara Province, constitute a forest region, and is managed by the Batulanteh Production Forest Management Unit (Kesatuan Pengelolaan Hutan Produksi) as prescribed in the Minister of Forestry Decree (SK. 342/Menhut-II/2011) (Julmansyah, 2014. It extends from the coast to the summit of Mt.…”

“…The sum of Importance Values of all species in a family entailed the Family Important Value (FIV) (Kartawinata et al,2004). Shannon's index of diversity was calculated using the formula:…”