The results showed that the species composition in the LP was very low and only 16 species of
16 genera in 11 families were found. Leucaena had a high stem density and basal area cover of 1,196.7
stems.ha-1 and 13.92 m2.ha-1, respectively. The high density created a closed canopy which reduced the
relative light intensity measured as mean ± SD on the fl oor (18.5 ± 5.5%) which was similar to that of
the RF (15.56 ± 2.8%). The distribution of the diameter at breast height of Leucaena fi tted a negative
exponential growth curve function (r2 = 0.94), indicating the species had successful natural regeneration
which was not only from seedlings but also from coppiced stems. The natural regeneration of native
species from the RF towards the LP was highly signifi cantly (ANOVA, P < 0.001) different for both the
stem density and species number. The stem densities of trees, saplings and seedlings of native species were
greater in the RF than in the LP. In addition, not only the native climax species but also pioneer species
had less success in establishment in the LP. This would suggest that Leucaena plays an important role
in restricting natural forest regeneration by its invasive growing habit which reduces light transmittance
to the forest fl oor.
Keywords: invasive species, forest restoration, edge effect, natural regeneration, vegetation dynamics