Tree Species Diversity, Richness, and Similarity in Intact and Degraded Forest in the Tropical Rainforest of the Congo Basin: Case of the Forest of Likouala in the Republic of Congo

Abstract

Trees species diversity, richness, and similarity were studied in fifteen plots of the tropical rainforests in the northeast of the Republic of Congo, based on trees inventories conducted on fifteen 0.25 ha plots installed along different types of forests developed on terra firma, seasonally flooded, and on flooded terra. In all of the plots installed, all trees with diameter at breast height, DBH ≥ 5 cm, were measured. The Shannon diversity index, species richness, equitability, and species dominance were computed to see the variation in tree community among plots but also between primary forest and secondary forest. A total of 1611 trees representing 114 species and 35 families were recorded from a total area of 3.75 ha. Euphorbiaceae was the dominant family in the forest with 12 species, followed by Fabaceae-Mimosoideae (10 species) and Phyllanthaceae (6 species) and Guttiferae (6 species). The biodiversity did not vary greatly from plot to plot on the whole of the study area (3.75 ha). The low value of Shannon index was obtained in plot 11 ( = 0.75) whereas the highest value was obtained in plot 12 ( = 4.46). The values of this index vary from 0.23 to 0.95 in plots P11 and P15, respectively. Results obtained revealed high biodiversity of trees of the forest of Impfondo-Dongou. The information on tree species structure and function can provide baseline information for conservation of the biodiversity of the tropical forest in this area.

Phytoecological studies of some protected and degraded forest areas of Lowland Humid forest, Ondo state Nigeria: a Comparative approach

“…Isichei (1995) also reported that Nigerian rainforest ecosystem is dominated by members of Sterculiaceae, Moraceae, Ulmaceae and Meliaceae families. The dominant families represented in this study sites differ from the families (Euphorbiaceae, Mimosoideae, Rubiaceae and Guttiferae) reported by Ifo et al (2016) in their study of a similar ecosystem.…”

Relationship between Tropical Forest Distribution and Soils on Different Types of Mother Rocks in the Republic of Congo

“…The equitability index is the Shannon Maximum Diversity Index report. It marks the level of diversity achieved by the system relative to the maximum possible (Ifo et al, 2016).…”

“…The values of the Piélou index are between 0 and 1. When they tend to 0, a dominance phenomenon is revealed and when they tend to 1, the index marks a regular compensation of individuals among species (Ifo et al, 2016).…”

Changement De Couverture Forestière Dans Le Département De La Likouala (République Du Congo) Durant La Période De 1986 À 2015

“…Cette pratique agricole est associée à des feux de végétation et à l'abattage des arbres pour la fabrication de pirogues, des constructions des maisons, la récolte du miel et l'obtention du bois de chauffe. Ces différentes activités ont par ailleurs un impact sérieux sur la biodiversité végétale des forêts de la zone d'étude (Ifo et al 2016).…”