Tropical forest restoration in Central Africa as nature-based solution for climate change mitigation

In this thesis, we use major nature-based solutions approaches to address biodiversity loss and enhance forest carbon sequestration capacity, which has substantial human well-being benefits in central Africa and contributes to climate change mitigation. Our main objective was to advance scientific understanding of forest carbon estimates and forest restoration approaches that enable the tropical forest of central Africa to absorb atmospheric CO2 at levels higher than the reference values observed in natural forests. First, we examined the pith-to-bark variation in wood density, a key variable influencing aboveground forest carbon estimate. Next, we quantified the recovery of carbon stock and biodiversity in a natural forest regeneration experiment conducted in an artificial savanna following fire suppression. Lastly, we assessed the potential of selected native tree species for tree-based restoration initiatives in central Africa, hypothesizing that long-lived native tree species with higher wood density are more effective in supporting long-term carbon sequestration. Our key findings lead us to conclude that nature-based solutions for forest restoration must be biome-appropriate. We highlighted major biome-appropriate nature-based solutions approaches in central Africa, emphasizing the success of fire exclusion in artificial savannas to facilitate natural regeneration and the use of native species as suitable biome-appropriate alternatives to exotic species plantations for forest restoration initiatives in central Africa.