Plant community formation and species distribution pattern in relation to environmental variables in Endiras Natural Forest, northwest Ethiopia

Abstract

The study was conducted in Endiras Forest, northwest Ethiopia, to evaluate the effects of environmental variables on the patterns of plant community formation. A systematic random sampling technique was used to collect vegetation data from 56 (20 m × 20 m) plots laid at 100 m intervals on ten transects. In each plot, the species encountered and its percent cover abundance were recorded, which was later transformed into a modified Braun-Blanquet scale. The composite soil samples collected from 15 cm × 15 cm subplots were examined for 13 soil parameters. Communities were determined using cluster analysis. The Shannon-Wiener index was employed to quantify species diversity. The relationships between species and environmental variables were evaluated using canonical correspondence analysis (CCA). Seventy-three woody plant species, distributed in 40 families, were documented. Fabaceae was found to be the most species-rich family (20.55%). Five communities were generated from the cluster analyses that vary in diversity. Nine environmental variables were found to be significant in determining patterns of community formation (P < 0.05). Organic matter, pH, and altitude, highly correlated with CCA axis 1, largely shaped the community formation patterns. Various patterns of community formation demonstrate the need to design different conservation measures.

Keywords

• conservation
• endiras forest
• environmental gradients
• indicator species
• species diversity