Floristic Composition and Structural Analysis of Gashaka-Gumti National Park Woodland Zones, Taraba State

Gashaka-Gumti National Park, straddling Taraba and Adamawa States in North East Nigeria, is Nigeria's largest national park and one of West Africa's most biodiverse protected areas, yet detailed botanical documentation of its woodland zones remains limited. This study assessed the floristic composition and structural parameters of the Guinea savanna woodland zones in the Gashaka area of the park. Forty 25m x 25m quadrats were systematically established, and all woody species with diameter at breast height above 5 cm were recorded. Herbaceous layer composition was assessed within nested 5m x 5m plots. Species diversity indices, basal area, stand density, and importance value index were calculated. A total of 67 woody species from 33 families were recorded. Combretaceae, Leguminosae, and Bignoniaceae were the most represented families. Isoberlinia doka and Terminalia laxiflora dominated by importance value. Herbaceous layer diversity was high (78 species), dominated by Andropogon gayanus and Hyparrhenia spp. Stand density averaged 342 trees per hectare, with basal area of 24.7 m2/ha. Community structure showed a reverse J-shaped diameter distribution, indicating active recruitment. Evidence of anthropogenic disturbance from illegal logging and charcoal production was noted in 35% of quadrats. The study concludes that the Gashaka woodland zones retain high botanical diversity but face growing disturbance pressure, and recommends enhanced boundary enforcement and community conservation education programmes.

Keywords: floristic composition, woodland, Gashaka-Gumti, structural analysis, Taraba State