Elateriospermum tapos Blume(Euphorbiaceae) in West Kalimantan: Spatial Distribution, Survival and Growth in a Mixed Dipterocarp Forest.

Abstract

The spatial distribution, survival and growth of Elateriospermum tapos Bfume (Euphorbiaceae) were studied from the data of a L-ha permanent plot at Gunung Berui, West Kalimantan. In the plot, number of species and individuals of Euphorbiaceae were 35 and254, respectively and the most abundant and dominant was E. tapos. Forty four percent of seeds produced in a mast fruiting season could be escaped from predators and germinated into seedlings. The number ofthe established siedlings was drastically dropped in the next year of the mast fruiting and slightly increased in the second year, The species has classical inverse J-shaped frequency size distribution, suggesting its continuous regeneration. The species was contagiously distributed in the plot. Mortality of shorier seedlings was higher than that oftaller seedlings, and the mortality ofseedlings in the gap was slightly higher than that of in closed forest. The mortality rate of seedlings was not related to the density oflohort seedlings and variables representing stand structure. The relationships among measured tree dimensions drew a simple linear; suggesting the growth pattern of tree dimensions in each individual plant was closely dependint one to another. The RGR-height tended to decrease in hyperbolic manner by increasing the hiight of seedlings and saplings, and the RGR-height in the gap were consistently higher than that in the closed forest. The RGR of height on seedlings and saplings or the RGR of diameter on trees in the sub-plots was not significantly related to the variables representing stand structure and relative light intensity ambient the individuals. Key