Kelbessa, Ensermu (Professor)Abebe, Arayaselassie2021-12-132023-11-082021-12-132023-11-082013http://etd.aau.edu.et/handle/123456789/29246Forest is a dynamic place where changes occur continuously and these changes bring about different structural changes in the forest stand. Change in the recruitment and forest community depends on the dynamics and formation of canopy gaps. Canopy gaps and their dynamics in regeneration were investigated in Gera Forest of Jimma Zone Oromia Regional State, located western of Ethiopia at an altitude range of 1600 2400 meter above sea level. In the Forest the main types of natural disturbance occurred through uprooting of trees and broken branch or crown. These causes are directly related with natural causes like thunder and wind. Prunus africana was found to be most affected in the disturbance, forming six gaps in the Forest. Including Prunus africana 13 species were found to be gap formers. The mean DBH of the gap formers is 48.33 cm2 and mean of the gaps formed became I 90. 83. Twenty eight species were investigated as gap filler species in the Forest. Among the gap fWers Millettia ferruginea was found to be in more gap areas than other species. Croton macrostachyus was the most dominant species that occurred in higher number (i.e. I I 8 individual/hectare) in the gap areas. The negative correlation between species density and gap area shows that both factors have low effect on gap regeneration and recruitment in Gera Forest. The replacement probability in the Forest is weak except Millettia ferruginea, Syzygium guineense and Prunus africana, all the rest of the gap formers are replaced by other nongapforming species. Dominant species in the Forest were not found being replaced by their own seedlings or saplings and among the ten woody dominant species only seven had sapling and five had seedling stages.enCanopy Gaps, Regeneration, Disturbance Dynamics, gap makers, Gap Fillers,Thesis