Human disturbances lead to forest degradation and a drastic reduction in forest area. In Africa, the most affected continent by this phenomenon, selective cutting of trees remains the main forest management strategy. However, the effects of management on biodiversity are insufficiently known, particularly in Africa. We investigated how forest management affects tree species diversity, composition, size structure and carbon biomass of mature and juvenile trees in the sudanian domain of Senegal by comparing unmanaged forests and three types of managed forests, while considering the disturbance level of each stand. We collected floristic data on five and fifteen unmanaged and managed forest stands, respectively. We calculated species richness, the Shannon-Wiener diversity Index (alpha, beta and gamma), as well as carbon stocks of trees for each forest stand. Then we fitted linear models to estimate the differences between forest types for each index. We also analyzed tree size structure and species composition of highly valuable species. In total, 26,009 mature and juvenile trees in 183 species were recorded. Our findings showed that management status and disturbance level affect tree species in different ways and that disturbance level explains a greater proportion of the variation in species diversity than management status. Considering alpha, beta and gamma diversity, we found no significant association between any of these metrics and management status, for either mature or juvenile trees. Disturbance level was only significantly associated with the gamma diversity of mature trees. Species composition of juvenile trees of highly valuable species was significantly associated with both management status and disturbance level, unlike mature tree species composition where the associations were not significant. The distribution of mature tree diameter forms an inverted J-shape for each management category and disturbance level. However, neither the median tree diameter nor the median absolute deviation presented significant differences as a function of management status or disturbance level. For carbon stocks, none of the differences observed by management status and disturbance level are statistically significant. Our findings indicated that forest management in the sudanian zone affects species composition more than diversity and that mature trees respond differently than juvenile trees. Disturbances more than forest management were the underlying process for biodiversity changes both in managed and unmanaged forests. These findings suggest a better protection of unmanaged forests, and also a development of specific conservation action plans for highly valuable species, especially for species that are threatened at national or global levels in order to minimize their risk of local extinction.

Forest management can have major impacts on the dynamic of ecological communities, including shifts in reproduction and survival strategies in newly recruited individuals. This study aims to predict the probability of presence of saplings of various species in managed forests in the Sudanian domain of Senegal based on their functional traits. Data on functional traits and the main commercial and domestic uses of twenty high-socio-economic value species were collected, along with their presence-absence, in 12, 832 plots from twenty sites in Senegal's savannahs spanning four different types of forest management, including unmanaged forests, old managed forests, recently managed forests, and community reserve forests. Mixed logistic regression models were used to predict whether high-value species would be present in different forest management types, depending on their main uses, and regeneration, growth and reproduction functional traits. We hypothesised that forest management would favour species with more efficient colonising and competitive abilities, particularly at high levels of disturbance. Our findings demonstrated that unmanaged forests were more likely to host high-value species, regardless of their functional traits and main uses. These protected forests also hosted the greatest variety of regeneration functional traits, heights and uses. Old managed forests were more likely to host high-value species compared to recently managed and community reserve forests. Moreover, high-value species capable of vegetative regeneration and those with low maximum height were more likely to occur in all types of forests, but this trend was more pronounced under higher management and disturbance intensities. This study highlights that the availability of forest products can be optimised by encouraging management strategies that promote a diversity of functional traits rather than the selective harvesting of certain high-value species. Additionally, the temporal variation in the responses of tree species could be beneficial for forest management, with more diverse values of functional traits and more high-value species being present in older managed forests relative to newly managed forests. These results indicate that it is essential to promote forest resilience after management by protecting high-value species that have the potential to restore forest functional composition over time in managed forests.