Woody Species Diversity and Structure of Aba Sena Natural Forest, Gimbi District, West Wollega Zone, Ethiopia

Abstract

The study was conducted in West Wollega, Gimbi District aimed at generating data on woody species diversity, Structure and community types of Aba Sena Natural forest. Five transect lines having a distance of 500 m from each other were laid at different altitudes. Quadrat size of 20 m ×20 m (400 m²) were established systematically at every 25m interval along the transect lines. Data on woody species were collected from a total of 40 sampling plots. A total of 69 woody species belonging to 67 genera and 34 families were identified in Aba Sena Natural Forest categorized in plant communities. Species diversity was determined using Shannon Wiener diversity index (H`). Plant community types were determined using PC-ORD version 5.3 for windows. The overall Shannon-Wiener Diversity Index (H`) and the evenness values for the entire forest were 3.76 and 0.62 respectively. The most abundant woody species in their order of highest density were Ficus sur, Pouteria adolfi-friederici, Terminalia macaroptera, Ficus vasta, Syzygium guineense, Ochna holstii, Albizia grandibracteata respectively. The basal area of the forest is 51.68 m² ha -1 . The population structure of the forest indicated that there have been high forest degradation in the area and therefore, conservation of species, ecosystem restoration and sustainable use of the forest genetic resources are recommended as a result of this study