FLORISTIC COMPOSITION, POPULATION STRUCTURE AND REGENERATION STATUS OF WOODY PLANT SPECIES OF DUGUNA FANGO FOREST IN WOLAITA ZONE, SOUTHERN ETHIOPIA

Abstract

Forests globally are known to be critically important habitats for the biodiversity they contain and for the ecological functions they serve. The study was conducted to assess the floristic composition, population structure, and regeneration status of woody plant species in the study area. Systematic sampling method was used to collect vegetation data. Accordingly, 40 sampling plots of 20m x 20m (400m2 ) were established systematically at every 200m interval along three (3) transect lines which are 300m apart to sample woody species. In each plots all woody species were recorded with their number counted and DBH measured for those with DBH>2cm. The collected data analysis was performed on the bases of height, DBH and basal area per hectare by computing the density of individuals with DBH>2cm, 10cm and 20cm. Fifty four woody species belonging to 24 families and 42 genera were recorded in the forest. The collected specimens were composed of 72% of trees, 26% shrub and 2% liana. The most dominant families were Fabaceae, Euphorbiaceae, Moraceae and Tiliaceae. The study forest has 3.73 and 0.94 Shannon weiner diversity index value and evenness value respectively. The total stem density of woody species whose DBH>2cm recorded in study forest was 603.03 individuals/ha. The total basal area of woody species in the study area was 38.785m2 /ha. The dominant and ecologically most important tree species in study forest on the basis of their importance value index (IVI) value were Maesa lanceolata, Combretum molle, Syzygium guineense, Ficus sur, Ficus sycomorus, Dodonea viscosa, Trichalia emetica and Maruwa (unidentified). The cumulative DBH class distribution showed that large number of individuals fall in lower DBH classes, which shows that this vegetation is in a good regeneration status. However, grazing by domestic livestock, cultivation and cutting of trees for fuel and construction purpose retard regeneration processes of trees and shrubs. These factors impose rapid degenerative changes on the forest. By taking this issue into action as possible future scenario underlines the need for management intervention to increase the quality of regeneration of the forest