Effects of tree species heterogeneity on leaf fall in primary and logged dipterocarp forest in the Ulu Segama Forest Reserve, Sabah, Malaysia

Effects of tree species heterogeneity on leaf fall were studied in a primary (4 ha) and in a selectively logged forest plot (2.5 ha) in the Ulu Segama Forest Reserve, Sabah, Malaysia, from April 1988 to December 1989. Leaf fall was collected at 30 sampling points in each plot, and identified to species. Dipterocarpaceae, Euphorbiaceae, Lauraceae, Fagaceae and Meliaceae are important tree families in both plots with regard to their contribution to total basal area, tree density and annual leaf fall. The total number of tree species was higher in the primary forest plot (267) than in the logged forest plot (218), although the number of climber species was higher in the logged forest (44) than in the primary forest plot (33) (...)