Impact of anthropogenic disturbance on tree species diversity, vegetation structure and carbon storage potential in an upland evergreen forest of Ghana, West Africa

Abstract

The impact of anthropogenic disturbance on tree species diversity, vegetation structure and carbon storage potential was assessed in an upland evergreen forest on a disturbance gradient (highly stressed, moderately stressed and non-stressed vegetation) in the Atewa Range Forest Reserve. Five spatially separated plots with sizes 50 × 50 m were demarcated in each gradient and sampled for vegetation and soil attributes. Specifically, we sampled tree species diversity, vegetation structure and carbon storage potentials in each gradient. A total of 193 tree species belonging to 44 families and 131 genera were recorded. Tree species composition and diversity differed across the gradient. Significantly higher species diversity was recorded in the non-stressed vegetation gradient than in the stressed vegetation gradients. Similarly, the gradients differed in terms of basal area, the density of stands, the height of trees and carbon stock with significantly higher attributes in the non-stressed than the stressed vegetation gradients. Only the basal area and height of stands correlated significantly with tree carbon stock. Anthropogenic disturbances (illegal logging, farming, mining) contributed to the reduced tree species diversity, density of stands and removal of mature trees, which translated into a reduction in the forest's ability to store carbon