Floristic Composition of Trees in the Lowland Dipterocarp Forest of Kuala Keniam, Taman Negara, Pahang, Peninsular Malaysia

Abstract

Abstract A study was conducted to determine the floristic composition and community structure of trees in lowland dipterocarp forest in Kuala Keniam, Taman Negara, Pahang. This forest is classified as a primary forest and among the oldest rain forest in the world. Five experimental plots with the dimension of 25 m x 20 m each (0.25 ha in total) had been established. The census was carried out for all trees with diameter at breast height (DBH) 5 cm and above. Species composition comprised of 244 individuals from 141 species, 94 genera and 36 families. The total number of taxa is varying across the five plots with the highest total number of families and species recorded in plot 5 with 21 and 43 taxa each. The lowest total number of families and species were recorded in plot 1 with only 14 families and 23 species. Euphorbiaceae is the most speciose family with 20 taxa and 66 individuals followed by Annonaceae with 14 taxa and 19 individuals. These two families are common in the lowland dipterocarp forests in Peninsular Malaysia. Main canopy and understorey and group were recorded with the highest number of species and individuals with 52 and 45 of species and 91 and 75 of individuals, respectively. Pioneer is very rare and was only represented by a single stem of Cratoxylum formosum and Sapium baccatum. Three species, namely Koompassia malaccensis, Elateriospermum tapos and Mallotus leucodermis were represented as the highest total number of individuals for DBH classes of ≥ 5 cm, ≥ 10 cm, ≥ 15 and ≥ 20 cm.