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Ehouman, E.

Publications and source records attributed to Ehouman, E..

2 recordsLinked to original sources
bioRxiv2026

Regenerating forests around Taï National Park sustain biodiversity despite constrained floristic recovery

Extensive deforestation and disturbance have reshaped forest landscapes in West Africa, including areas surrounding Tai National Park, the largest remaining block of Upper Guinean rainforest. Although many degraded areas are currently undergoing regeneration, the capacity of these secondary forests to recover their biodiversity attributes remains insufficiently assessed within this park. This study quantifies the multidimensional restoration of biodiversity across 125 secondary forest plots and 15 primary forest plots representing 14,731 inventoried individuals in four sectors of the park. Using a Bayesian modelling framework, we estimate recovery trajectories of Shannon diversity, floristic composition, functional traits (wood density, leaf mass per area, seed mass), and conservation-relevant species. The different biodiversity attributes recovered at contrasting rates. Diversity was restored more rapidly ({lambda} = 0.06) than floristic composition ({lambda} = 0.03), and these recovery varied according to environmental variables. Among these, the presence of remnant trees showed the highest median on diversity (0.53 {+/-} 0.61) and floristic composition (0.37 {+/-} 0.17), promoting the rapid recovery of both attributes, followed by prior land use, particularly cocoa farming which also positively influenced the recovery of alpha diversity ({lambda} = 0.03) and floristic composition ({lambda} = 0.02). Regarding functional traits, they displayed contrasting dynamics: specific leaf area and seed mass recovered rapidly along successional gradients, whereas wood density followed a more gradual recovery trajectory. From a conservation perspective, although the proportion of IUCN Red List species remained stable along the successional gradient, old-growth indicator species were significantly more abundant in primary forests. To ensure the long-term conservation of biodiversity, protecting both primary and regenerating forests is essential to preserve the ecological resilience of this park.

ecology↗
bioRxiv2026

Microbial succession in West African secondary forests: rapid internal stabilisation without convergence toward old-growth reference states

Secondary forest succession following agricultural abandonment is a dominant land-use transition across the tropics, yet whether soil microbial communities recover toward old-growth forest reference states remains poorly understood, particularly in West Africa. Here, we investigated the successional dynamics of bacterial and arbuscular mycorrhizal (AM) fungal communities along post-agricultural chronosequences spanning 1 to 43 years across six classified forests in Cote d'Ivoire, using Bayesian hierarchical models applied to amplicon sequencing data. Both guilds attained moderate to high alpha diversity within the first decade of succession; AM fungal diversity showed moderate evidence of age-related increase thereafter while bacterial diversity showed no directional trend. Pairwise turnover analyses revealed progressive internal convergence in AM fungal communities with plots farther apart in successional time becoming more compositionally similar, while bacterial communities showed only a weak and uncertain tendency in the same direction. Beta-dispersion modelling further indicated progressive within-forest homogenisation of AM fungal communities across abundance-weighted metrics, while bacterial assemblages showed no such stabilisation. Despite this internal convergence, compositional distances to old-growth reference plots remained persistently high for both guilds throughout the chronosequence, with no statistical evidence of recovery toward old-growth states across any dissimilarity metric or guild within the 40-year window. Indicator species analysis identified no robust stage-specific taxa after correction for multiple testing. These results indicate that microbial succession in post-agricultural West African forests is characterised by rapid early reorganisation followed by stabilisation into site-specific assemblages that remain persistently distinct from old-growth reference communities. This outcome challenges the direct application of classical vegetation successional theory to soil microbiomes and indicates that no detectable recovery toward old-growth microbial community states was observed within the 40-year chronosequence.

ecology↗