Plant Community Analysis and Phytodiversity Study of Eboh Forest in Ahoada East, Rivers State, Nigeria

Abstract

Background: Plant communities provide critical information on species composition, structure, and ecological processes, particularly in tropical forest ecosystems experiencing increasing anthropogenic pressure. Rapid urbanization, agricultural expansion, and population growth are contributing to forest degradation in the Niger Delta, making phytodiversity assessment essential for conservation and sustainable management. Aim: This study assessed the plant community structure and phytodiversity of Eboh Forest in Ahoada East Local Government Area, Rivers State, Nigeria.  Study Design: Random quadrat sampling design. Place and Duration of Study: Eboh Forest, Ahoada East LGA, Rivers State, Nigeria, between May and July 2025. Methodology: Vegetation sampling was conducted using eight (8) randomly distributed 10 m × 10 m quadrats. All plant species within each quadrat were identified, enumerated, and analyzed for species composition and population structure. Standard ecological methods were used to compute percentage frequency, density, abundance, relative frequency, relative density, relative abundance, and importance value index (IVI). Species diversity was determined using the Shannon–Wiener index, while species evenness was calculated using Pielou’s index. Results: A total of 78 plant species belonging to 36 families were recorded, comprising 33 herbs, 12 shrubs, and 33 tree species. The forest had a total of 13,489 individual plants. Scleria depressa, Manihot esculenta, Alchornea cordifolia, Elaeis guineensis, Pterocarpus santalinoides, and Raphia hookeri showed 100% frequency of occurrence. Thaumatococcus daniellii and Mimosa diplotricha recorded the highest densities (1.00/m² and 0.91/m², respectively), while M. diplotricha exhibited the highest abundance (1.83/m²). The highest IVI values were recorded for M. diplotricha (12.93), T. daniellii (12.28), and Zea mays (9.30). Shannon diversity index was 3.38, indicating high species diversity, while species evenness was 0.91, suggesting relatively uneven species distribution. Conclusion: Eboh Forest exhibits high species richness and diversity, with a balanced representation of herbs, shrubs, and trees, but with dominance by a few species. The forest retains characteristics of tropical freshwater swamp vegetation. Conservation strategies are recommended to minimize anthropogenic disturbances and ensure long-term ecological sustainability.