Review on Woody Plant Species of Ethiopian High Forests

Abstract

Ethiopia is one of the top 25 biodiversity-rich countries in the world, and hosts two of the world’s 34 biodiversity hotspots, namely the Eastern Afromontane and the Horn of Africa hotspots. It is also among the countries in the Horn of Africa regarded as major Centre of diversity and endemism for several plant species. The Ethiopian flora is estimated to about 6000 species of higher plants of which 10% are considered to be endemic according to Institute of Biodiversity Conservation (IBC) of Ethiopia, 2012 and woody plants constitute about 1000 species out of which 300 are trees.Forests form the major constituents of vegetation resources and thus conservation of forest genetic resources (FGRs) is among the priority areas of biodiversity conservation in Ethiopia. Forests undergo changes in various ways. Its areas can be reduced either by deforestation or by natural disasters such as volcanic eruptions. As a result, the expanse or vastness of forest areas is declining across the globe, partly through logging activities and also due to conversion of habitats to croplands (agricultural expansion) accounts for up to 40 percent of Ethiopian forest losses. A woody plant is a plant that produces wood as its structural tissue. In Ethiopia, biodiversity varies in space and time, and understanding patterns and drivers of Variation in biodiversity distribution has been a central topic in ecology. A diversity index is a mathematical measure of species diversity in a given Community. Based on the species richness (the number of species present) and species abundance (the number of individuals per species). Limited governmental, institutional, and legal capacity; population growth; land degradation; weak management of protected areas; and deforestation, invasion of exotic species, habitat destruction and fragmentation, over utilization, pollution, climate change, trade and transportation are some of threats and causes for loss to biodiversity of Ethiopia. To identify the richness, evenness, endemism, exoticness, enlargement, extinction rate, and to know appropriate management approach, diversity assessment has indispensable role. And ecologists and other related researchers and scientists use different indices to calculate diversity parameters. Among the indices, Shannon and Simpsons indices are commonly used one. Strong work is required to conserve diversity of Ethiopia.

Keywords: high forest, woody plant, diversity assessment, diversity index, species richness, species evenness