Abstract

This study assessed the diversity and distribution of trees and shrubs in a 16 ha disturbed plot in the Takamanda Rainforest. Linear transects (8) were laid in the field which radiated from the centre of the plot. The girth of the trees and shrubs were measured and species identified. A total of 99 species (72 trees and 27 shrubs) belonging to 87 genera and 34 families were recorded. Caesalpinaceae was the most represented tree family (9 species) while Rubiaceae was the most represented among shrubs (9 species). Baphia nitida recorded the highest tree density (143.75 individual’s ha^-1) and lowest tree density (1.56 individual’s ha^-1) was recorded for Khaya anthotera. The highest shrub density (192.19ha^-1) was recorded for Angylocalyx pynatii while the lowest was (1.56 ha^-1) was recorded for Voacanga africana. The girth class distribution showed a reverse J-shape distribution, with the highest densities in the lower girth (15-30 and 30-45 cm) classes. This decreases in density with the larger girth (> 75) class. The Importance Value Index (IVI) of trees was highest for Baphia nitida (20.06) while the lowest was recorded for Millettia sanagana (0.51). For shrubs, Chytranthus macrobotrys had highest IVI of 45.05 while the lowest was observed in V. Africana (1.24). Diversity index of trees and shrubs were 3.87 and 2.88, respectively. A dominance index of trees was 0.03 and that of shrubs was 0.08. The species evenness for trees (0.90) and shrubs (0.87) showed a slight variation in distribution. Abundance/ frequency ratio (A/F) for tree and shrub was >0.05 and showed a clumped pattern of distribution. Sustainable management of the forest would continue to provide goods and services for communities around the rainforest.

Key words: Diversity index, distribution, abundance/frequency ratio’ contagious, importance value index, evenness index.