Plant diversity and tree community structure along an elevation gradient in Apra Hills Sacred Grove, Ghana

Abstract

The Apra Hills Sacred Grove has one of the best patches of the threatened Southern Marginal Forest of Ghana, yet a study on vegetation has not been undertaken. We evaluated plant diversity and tree community structure in relation to an elevation gradient using 25 m x 25 m plots demarcated along a 1km transect in the grove. Vascular plants within the plots were identified, and trees with diameter-at-breast-height (dbh) ≥ 10 cm were measured. A total of 128 plants taxa were identified, and 21 species of trees were enumerated. Mean tree density was 292.33 ± 14.05 per ha, and dbh-size class distribution of the trees showed an inverted J-shape curve. Overall plant species richness decreased with increasing elevation whereas tree species diversity increased with elevation. But the relationships between elevation and tree species richness, tree density and basal area were statistically insignificant. Future studies on effects of edaphic and anthropogenic factors along the elevation gradients would improve our knowledge about the distribution of the plant diversity as well as their conservation.