Spatial patterns and habitat associations of Fagaceae in a hill dipterocarp forest in Ulu Gadut, West Sumatra

• Published in: Journal of tropical ecology Vol. 24; no. 5; pp. 535 - 550
• Main Authors: Nishimura, Sen, Yoneda, Tsuyoshi, Fujii, Shinji, Mukhtar, Erizal, Kanzaki, Mamoru
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.09.2008
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; coexistence; Dipterocarpaceae; dispersal constraint; Equilibrium; Fagaceae; Forest ecology; Forest habitats; Forest trees; Fundamental and applied biological sciences. Psychology; habitat preference; Habitat preferences; Habitats; Land surveys; Montane forests; Mortality; niche partitioning; Plant ecology; Species; Studies; Synecology; Terrestrial ecosystems; Trees; Tropical rain forests; Ulus; habitat preference; niche partitioning; Dipterocarpaceae; Fagaceae; coexistence; dispersal constraint; Forests; Dicotyledones; Angiospermae; Ecological niche; Spermatophyta; Habitat
• ISSN: 0266-4674; 1469-7831
• DOI: 10.1017/S0266467408005269

Spatial distribution patterns and habitat associations of Fagaceae species in a Fagaceae-codominated hill forest in Sumatra were investigated. Ten Fagaceae species believed to be zoochorous (animal-dispersed seed) and five codominant canopy and emergent anemochorous (wind-dispersed seed) species from Anacardiaceae and Dipterocarpaceae were studied. Five Fagaceae species and all codominant anemochorous species were significantly aggregated while the other five Fagaceae species showed a random distribution pattern. The median distance of small saplings from the nearest reproductively mature tree tended to be shorter for aggregated species than spatially random species. This implied that some Fagaceae species dispersed over longer distances than anemochorous species. Relationships between four habitat variables and distribution of the target species were examined with torus-translation tests. Three Quercus and one Lithocarpus species showed positive habitat associations. Two Quercus species aggregated at the preferred habitat, but the others were randomly distributed. Thus tree species with specific habitat preference do not only aggregate at the preferred habitat. The three ridge-specialist Quercus species showed gradual changes in habitat association, which could reflect avoidance of competition among the species. Most of the Lithocarpus species showed little correlation with habitat variables. Coexistence of the three Quercus species partly reflected subtle differences in topographical preferences. Distribution of five of the six Lithocarpus species was unrelated to topography, so other mechanisms must be sought to account for the maintenance of coexistence in this species-rich genus.