Ecology and Development Series No. 10, 2003 - ZEF

Floristic analysis of the undisturbed forest4 FLORISTIC ANALYSIS OF THE UNDISTURBED FORESTVEGETATION AT YAYU: A POTENTIAL GENE RESERVE FORCOFFEA ARABICA4.1 IntroductionEthiopia has very diverse climatic conditions varying from hot and dry deserts in thelowland areas, parts of which are as deep as 116 m below sea level, to cold and humidalpine habitats in highlands, which rise to over 4000 m above sea level. Such diverseclimatic conditions and habitats partly contributed to the presence of high species diversityin plants and animals, making Ethiopia one of the top 20 richest countries of the world inbiodiversity (WCMC 1992). Forest is among the diverse ecosystems in Ethiopia, varyingfrom broadleaved deciduous woodlands in the lowlands to montane rain forests in thehighlands. Most of the montane rain forests occur in at altitudes ranging from 1500-2600 min the southwestern part of the country (Friis 1992). The montane rain forests of Ethiopiaare home to various endemic and indigenous plants (Mesfin 1991b). They also contain thewild gene pools of some important plants for food and agriculture such as Aframomumcorrorima, Coffea arabica and Piper capense.FAO (1981) estimates that about 40% of the land surface of Ethiopia were underforest cover about a century ago. By 1960, the forest cover of Ethiopia had dwindled toabout 3.4% (Aklog 1990). The highlands of Ethiopia in fact have been highly deforested inthe past 100 years, and even today, deforestation continues to be the major threat to theremaining forest areas in the southwestern part of Ethiopia. In the early 1970s, about 40%of the SW highland plateau was covered by forest (Reusing 1998). Thirty years later, theregion has lost about 60% of its forest cover (Tadesse et al. 2002). This has also threatenedthe wild coffee populations and many other species. Nowadays, the forests with wild coffeepopulations are highly fragmented and isolated from each other.Such fragmented forest areas in the highlands of SW Ethiopia are the remaininglocalities for the conservation of the wild gene pool of the widely distributed and cultivatedArabica Coffee (Coffea arabica) and other plant species (Tewolde 1990; Tadesse et al.2002). The forests are also sources of livelihood for the local community who mainlydepend on the production of coffee from the wild trees (Tadesse and Denich 2001; Tadesse35