WOODY PLANT SPECIES COMPOSITION, DIVERSITY AND STRUCTURE OF WOODY PLANTS IN GAWUS NATURAL FOREST, SOUTH BENCH DISTRICT, BENCH SHEKO ZONE, SOUTH WEST ETHIOPIA

<strong>ABSTRACT</strong>: Woody species composition, diversity and structural analysis studies are essential for providing information on species richness of the forest, useful for forest management purpose and help in understanding the forest ecology and ecosystem function. This study was conducted on Gawus natural forest in South Bench district, Bench Sheko Zone, Southwestern Ethiopia. The objective of the study was to assess woody species composition, diversity, and structure and regeneration status of Gawus natural forest. Systematic samplings of 60 (20 m × 20 m) plots were laid along four line transects to sample trees, shrubs and lianas. In each main plot, subplots 2m×2m (4m2) were laid down to sample seedlings and saplings. The sample plots were laid at every 200 m interval along transects at 500 m apart. All trees and shrubs with Diameter at Breast Height (DBH) &gt; 2.5 cm were measured for height and diameter. Community classification was performed using R Software. Density, Frequency, Basal Area, dominance and IVI were computed to describe vegetation structure. A total of 61 woody species belonging to53genera and 31 families were recorded and identified. Out of these, Fabaceae was the dominant family representing 11.48% species and 7.84% genera, followed by Euphorbiaceae, Moraceae, Rubiaceae, Sapendaceae, Sapotaceae and Rutacea. Five plant communities were identified at the Gawus natural forest as result of hierarchical cluster analysis. Poutria adolfi-friedericii - Croton macrostchyus community (C1) is found to be the most diverse and the highest species richness, which is generally thought to indicate a more complex and healthier community. The density of woody species in Gawus natural forest gradually decreases with increasing DBH and height classes, which indicates that the vegetation was generally in a healthy and good regeneration status. The total density and basal area of woody species were 1007.50 individuals/ha and 214.61m2ha-1, respectively. The most frequently appeared woody species were Polyscia fulva (5.3%), Ficus sycomorus (5.08%), Mimusops kummel (4.85%) and Pavetta abyssinica (4.74). Important value index was within ranges 0.15 to 22.28 m2ha-1. The composition of seedling, sapling, and adult woody species was 1277.50, 1150.83, and 11007.50 individuals’ ha−1, respectively. Based on the results, floristic composition and medicinal values of the forest; raising local community awareness on conservation and sustainable use of the forest are suggested.