Preliminary study on plant ecology in Tangkahan Area, Gunung Leuser National Park

Abstract

Gunung Leuser National Park (NP) is the biggest NP in North Sumatra. Though very few plant ecological studies were conducted there. Most studies in Gunung Leuser NP are related with protected animals, such as Sumatran Tiger, Elephant or Orang Utan. Thus, the aim of this preliminary study is to understand the plant structure and composition in the tropical forest of Gunung Leuser National Park. A 0.5-ha plot was established near Gua Kambing, Tangkahan area in November 2015. All tree species bigger than 15 cm girth were recorded, measured, and identified. The dominant species were from Dipterocarpaceae, followed by Myrtaceae and Achariaceae. The total number of trees was 693 trees or 1,386 trees/ha with the total Basal area was 42.9m2/ha and the biggest diameter was 147cm. The results from diversity index analysis ((H’=4.43; D=0.97; α=75) confirm that the forest area had a relatively high diversity, with Agrostistachis sessilifolia dominates the understory layer. The Gua Kambing area had relatively high plant diversity, less disturbance, and bigger trees than other studied areas in tropical Indonesian forests in Sumatra.

Floristic composition and diversity at Keruing (Dipterocarpus spp.) habitat in Tangkahan, Gunung Leuser National Park, Indonesia

“…The average temperature at the study site ranged from 21.1˚C-27.5˚C with humidity between 80-100%. The average rainfall of this area ranges from 2,000-2,500 mm/yr (Susanti et al 2021) and is dominated by Dipterocarpaceae family. Historically, this forest was pressured by illegal logging by local villagers, which ended in 2001 (Wiratno 2013), and is currently managed by a local villager in partnership with the national park administrator as an ecotourism area destination.…”

“…There has been very limited research on the tree species in this area. Sari (2014) and Susanti et al (2021) conducted previous studies on plant ecology in this area and showed that the Dipterocarpaceae was the dominant family in Tangkahan area. The results of the study found that there were variations in the dominance of dipterocarp species at each growth stage.…”

“…As a conservation area, Tangkahan has several important fauna species, namely six primate species (Sumatran orangutan, siamang, gibbon, kedih, long-tailed monkey, and beruk), small squirrel, hornbill bird, srigunting batu, and eagle. In addition to animals, the Tangkahan area is home to various trees, and is generally dominated by the Dipterocarpaceae family (Sari 2014;Susanti et al 2021).…”

“…T here is little research on plant ecology in Gunung Leuser NP (Susanti et al 2021), let alone research focused on Keruing. Previous ecological studies on the plant were conducted several years ago (Sambas and Siregar 2004) or only focused on certain species, such as Koompasia excelsa and medicinal plants (Nurtjahja et al 2013;Warsodirejo et al 2020).…”