DIVERSITY, DIAMETER STRUCTURE AND SPATIAL PATTERN OF TREES IN A SEMI-EVERGREEN RAIN FOREST ON LANGKAWI ISLAND, MALAYSIA

Abstract

Species diversity, diameter structure and the spatial pattern of trees were studied in a 2.4-ha plot of the semi-evergreen rain forest at Machinchang Forest Reserve, Langkawi Island, Malaysia. The 3518 trees ≥ 5 cm dbh studied comprised 208 species from 45 families, including 156 species in 41 families for 1484 trees ≥ 10 cm dbh. Number of species per area was higher in trees 5 - < 10 cm dbh than in trees ≥ 10 cm dbh. The plot was dominated by Anacardiaceae, particularly Swintonia floribunda, which was the most frequent (11.1%) and displayed the greatest basal area (12.8%) of all trees. Swintonia floribunda was consistently dominant in all five dbh classes defined from the M-w relationship. Among 64 common species examined for spatial pattern, 2, 42 and 20 species exhibited uniform, random and clumped distribution respectively. The plot was characterised by lack of family dominance by Dipterocarpaceae.