Woody Species Population Structure and Regeneration Status in Hereje Natural Forest, Southwest Ethiopia

Abstract

Finding potential management interventions to lessen the negative effects of deforestation and forest degradation requires understanding the population structure and regeneration status of woody species in Ethiopia’s Hereje Natural Forest. The local population relies on the forest for ecosystem services, which in turn, alters the plant diversity and age structure of the forest and the regeneration status for future generations is uncertain. Hence, this study was conducted with the objective of determining the Woody Species population structure and regeneration status of woody species in Hereje Natural Forest in Southwest Ethiopia Three parallel transect lines (every 100 m) were established along altitudinal gradients, and 45 plots of 20 m x 20 m were used to collect vegetation data. Living woody species were counted and measured using diameter at breast height (DBH) measurements for DBH>2.5cm in each plot. Each main plot had five 2mx2m (4m2) subplots, one in the center and four at the corners. The regeneration status of each subplot was assessed by the species of woody plants present (seedlings, saplings, and mature trees/shrubs).On the studied plots, a total of 44 plant species were identified and classified into 28 families and 41 genera. The most relatively dominant species in the Hereje forest were Syzygium guineense (24.47%), Ficus sur (20%), Combretum molle (18.58%), Croton macrostachyus (18.11%), and Terminalia schimperiana (9.29%). According to the results, the density of tree species in the forest decreases as DBH classes increase. The predominance of small DBH classes is a result of excessive cutting for certain size classes by the local community, indicating extensive changes in the woody plant diversity and age structure. Overall, the forest's regeneration status was fair. Urgent interventions and enforced regulations are required to halt the major cause of forest deterioration, namely human-induced activities such as cattle grazing, illegal timber harvesting, and firewood collection. For long-term forest stability and biodiversity conservation, additional in-depth ecological studies are recommended regarding potential management interventions, monitoring protocols, and other ecological factors that contribute to the sustainable use of the forest and its products.