Plant Species Response to Coal Mining Sites in Kogi State

Coal mining activities are widely recognized for their capacity to alter species composition and ecological stability. This study assessed plant biodiversity responses to coal mining disturbance in the coal belt areas of Kogi East, Kogi State, Nigeria, using species diversity indices as ecological indicators. Vegetation data for this study were collected using line transects and nested quadrats. A total of 48 quadrats (50 × 50 m) were systematically laid along four parallel transects at 10 m intervals across Sites A, B, and C. From these, 24 quadrats were randomly selected using a table of random numbers, with eight quadrats chosen from each site, resulting in a total sample size of 24. Plant species diversity was quantified using the Shannon Wiener diversity index (H′), species richness, and Pielou’s evenness index (J′). Differences in diversity metrics among plot categories were evaluated using one-way analysis of variance (ANOVA). Results revealed that the control site (Plot C) consistently recorded the highest median values for Shannon diversity (H′ ≈ 3.65), species richness (47.5 species), and evenness (J′ ≈ 0.960), accompanied by relatively low variability (IQRs ≈ 0.180, 8.25, and 0.015, respectively), indicating a stable and well-structured plant community. In contrast, mined plots exhibited lower median diversity values and greater dispersion, with Shannon diversity medians of 3.59 (Plot A) and 3.51 (Plot B), richness medians of 45.5 and 43.5 species, and evenness medians of 0.938 and 0.955, reflecting heterogeneous recovery and ecological instability. However, one-way ANOVA results indicated no statistically significant differences among plot categories for Shannon diversity (F₂,₂₁ = 0.78, p = 0.472), species richness (F₂,₂₁ = 0.37, p = 0.696), or Pielou’s evenness (F₂,₂₁ = 2.48, p = 0.108). The study provides baseline ecological data critical for vegetation restoration and biodiversity management in coal mining landscapes of Kogi East. It is recommended that targeted ecological restoration programs be implemented alongside long-term monitoring to mitigate the impacts of coal mining on vegetation.