The community structure of a logged-over tropical rain forest in Mt. Makiling Forest Reserve, Philippines

The community structure of a logged-over tropical rain forest in Mt. Makiling Forest Reserve, Philippines. Community structure and species diversity were studied at a 4-ha tropical rain forest in Luzon Island, Philippines, 50 years after selective logging. The once selectively logged forest had high species diversity and a complex guild structure. The 4-ha plot recorded 3648 trees and palms of 179 species above 5 cm in diameter breast height (dbh). The dbh size of all trees and palms showed an inverse-J distribution with a maximum of about 150 cm. Species diversity indices for the 4-ha plot fell within the range of the indices previously reported for old-growth tropical rain forests in Southeast Asia. The dbh size distribution in the population of each component indicated that the community was composed primarily of shade-tolerant species. Most species with more than 1 per cent density or basal area of the plot total had an aggregate distribution, and nearly half of them showed a significant topographic preference. The smaller presence of dipterocarp species, which were the dominants in the original flora, indicated that the species have suffred heavy utilisation in the past, with the result that numerous non-dipterocarp tree species now formed a species-rich secondary tropical rain forest.