Abstract
Site-independent allometric relationships for above-ground weight were studied for three groups of mangroves: Rhizophora, Bruguiera, and other species. A hundred and one tree samples were collected from five forest sites where a major difference is geographical locality. For stem weight, a site-independent allometric relationship using the variable DBH2H or DR0.32H (DR0.3, = stem diameter at 30 cm above the highest prop root) was attained for each group, because the specific gravity of wood and overall stem shape are identical among the trees of the different sites. Although some mangroves showed difference in specific gravity of wood among different sites, this difference was not large enough to effect the site segregation of the allometric relationship for stem weight. The allometric relationships for the branch and leaf weights of all studied mangroves differed by site when we used DBH2H or DR0.32H as an independent variable. However, when we used the stem diameter at the height of the lowest branch DB as an independent variable, the difference in allometric relationships for both branch and leaf weights among sites became smaller. We discussed the application of the Pipe Model (Shinozaki et ai. 1964) for establishing site-independent allometric relationships common to a variety of geographically distinct mangroves.
