Landscapes and Ecosystems
Odzala-Kokoua National Park spans multiple biogeographic zones that together support regionally significant ecological processes.
Its location within the western Congo Basin enables high vegetative stratification and hydrological variability.
This internal diversity is what underpins species richness and spatial heterogeneity.
1. Forest Systems
Approximately 70 percent of the park is covered by moist evergreen rainforest, classified within the Guineo-Congolian phytogeographic zone.
Dominant tree families include Caesalpinioideae, Euphorbiaceae, and Sterculiaceae. These forests feature a three-layer canopy and maintain a closed structure except in disturbed zones.
Marantaceae-dominated understories are common across western and central blocks. These dense herbaceous layers form foraging corridors for western lowland gorillas and sitatunga antelopes. Duikers, hornbills, and frugivorous primates frequently visit treefall gaps and herb clearings.
Logging relics from the pre-2000s era remain detectable in some outer sections. However, regrowth metrics collected since 2012 indicate gradual structural recovery in those areas.
2. Savanna Patches
Although often overshadowed by the forest component, savanna mosaics cover significant portions of the park’s southern and eastern edges.
These are not true open grasslands but rather forest–savanna ecotones composed of Loudetia grasses, scattered Combretum shrubs, and terminalia species.
These areas are critical for the seasonal movement of forest buffalo and elephant populations. Fire frequency, soil depth, and water table elevation influence vegetation structure here more than elevation or rainfall.
3. Hydrological Zones
The park contains two principal rivers: Mambili and Lekoli, both of which serve as ecological corridors. Flood regimes vary between permanent swamp forest and seasonally inundated zones.
Bais, or natural saline clearings, are among Odzala’s defining features. They occur where subterranean waters bring mineral-rich substrates to the surface.
Notable examples include Mbouebe Bai and Lango Bai, each attracting megafauna daily to obtain minerals.
Peat deposits have been confirmed in the park’s northeastern quadrant. These soils have high carbon densities and are under review for valuation of long-term climate regulation.