Plants Species Composition, Vegetation Dynamics, and Soil Characteristics of the Ikot Akpa Etok Forest Ecosystem in Ibesikpo Asutan Local Government Area, Akwa Ibom State, Nigeria
Résumé
This study assessed the plant species composition, vegetation structure, and soil physicochemical characteristics of the Ikot Akpa Etok forest ecosystem in Ibesikpo Asutan, Akwa Ibom State, Nigeria, to understand soil–vegetation interactions in a regenerating secondary tropical forest. Soil samples were collected from Ikot Akpa Etok Community Forest, located in Ibesikpo Asutan Local Government Area, Akwa Ibom State, Nigeria. Composite soil samples were obtained at two depths: 0–15 cm (topsoil) and 15–30 cm (subsoil) using a soil auger. At each sampling point, three subsamples were collected, thoroughly mixed, and a representative sample taken for laboratory analysis. A total of 3,001 individual plants were recorded, representing 59 species across more than 30 botanical families. Trees were the dominant life form (42.3%, 1,271 individuals), followed by herbs (27.7%, 832 individuals), shrubs (19.5%, 584 individuals), and climbers (10.5%, 314 individuals). Biodiversity indices indicated high ecological stability, with Shannon–Wiener index (H′) of 3.7501, Simpson’s index (D) of 0.9705, and species evenness (E) of 0.9197, reflecting low dominance and balanced species distribution. Soil analysis revealed moderately acidic loamy sand (mean pH = 4.69), enriched with organic matter (mean = 5.08%), total nitrogen (0.13%), available phosphorus (75.42 mg/kg), and high base saturation (87.0%). These soil fertility indicators were positively correlated with vegetation abundance and diversity, underscoring their role in supporting regeneration and structural complexity. The co-occurrence of pioneer species such as Musanga cecropioides and Macaranga barteri alongside late-successional taxa suggests an advanced successional stage and strong regenerative capacity. The dense tree cover and elevated organic matter highlight the site’s potential as a biodiversity reservoir and carbon sink, with implications for climate regulation and ecosystem service delivery. The findings emphasize the need for conservation interventions that integrate enrichment planting, soil fertility management, and community-based stewardship to safeguard the ecological and socio-economic functions of this forest ecosystem.