Environmental factors influencing liana community diversity, structure and habitat associations in a tropical hill forest, Malaysia

Background: Although lianas are important in forest ecosystems, information on the environmental factors influencing their diversity, structure and habitat associations is scanty. Aims: This study had the aim of determining variation in liana diversity, structure and habitat associations across different topographic habitats, and the environmental factors influencing them, in the Penang Hill Forest Reserve, Malaysia. Methods: Liana diversity, structure and habitat associations were examined in 30 plots, 40 m x 40 m, randomly demarcated within three topographic habitats (flatland, slope and valley). The physico-chemical properties of the soils in the plots were determined and the altitude and slope of the plots recorded. Results: Liana species richness, diversity and structure varied significantly among the topographic habitats. Liana species richness, diversity and abundance variations were related to soil moisture, phosphorus content, pH and altitude, whereas liana diameter and basal area were associated with soil magnesium and slope. A total of eight species had a positive association with the habitat and a further six showed a negative association. Four species had a positive association with the flatland habitat, but only three and two species, respectively, with slope and valley habitats. The slope habitat gave the highest number of species that showed a negative association. Conclusions: Liana diversity and structure varied between habitats. Some liana species showed different associations with specific habitats. Environmental variables were identified that influence liana diversity, structure and habitat associations. The study provides important information about the factors influencing liana success, and these will be of value in liana conservation and management in tropical forests.