Abstract

The knowledge of forest floristic diversity is essential for assessing their health, as it impacts ecosystem services. The floristic diversity of 2 different forest types (moist evergreen and semi-deciduous) was assessed using the 25 m × 25 m quadrats method. The characterization of the forest types was based mostly on the species richness, floristic composition, and structural parameters of the stand, based on the important value index. The research question is, are there differences between the diversity and floristic composition of evergreen and semi-deciduous forests? Does the least studied diametric class (5-10 cm) also show differences between the two forest types? The results showed that family floristic composition in order of importance, Fabaceae, Annonaceae, Euphorbiaceae, Apocynaceae, and Malvaceae in the moist evergreen forest; and Malvaceae, Fabaceae, Annonaceae, Cannabaceae, and Moraceae in the semi-deciduous forest. In terms of species richness, semi-deciduous forests had 87 species, while moist evergreen forests had 199 species for trees with a diameter at breast height (dbh) of 10 cm or more. For trees with a diameter of 5 cm or more, semi-deciduous forests had 170 species, whereas moist evergreen forests had 282 species. The density of trees with a dbh of 10 cm or more was 453 stems ha^-1 in evergreen forests and 728 stems ha^-1 in semi-deciduous forests. There was no significant difference in the densities of trees with a dbh between 5 and 10 cm in the two forest types. The basal area was 49.71 m² ha^-1 for the semi-deciduous forest, compared to 33.94 m² ha^-1 for the moist evergreen forest. The Shannon index, a measure of biodiversity, was higher in moist evergreen forests (5.13) than in semi-deciduous forests (4.24).

Key words: Tropical rainforest, floristic diversity, floristic composition, forest inventory, Cameroon.