Ecology and Development Series No. 10, 2003 - ZEF

Impacts of human use on the forest vegetation5 IMPACTS OF HUMAN USE ON THE STRUCTURE AND SPECIESCOMPOSITION OF THE YAYU FOREST5.1 IntroductionApart from their function as reservoirs of biodiversity, forests provide differentecosystem services; forests also provide human beings with many goods and servicesfor livelihood. The use of forests and forest products dates back several centuries inhuman history. For instance, some 30,000 – 40,000 years ago, people in New Guineawere thinning forest trees to increase natural stands of Taro, bananas and Yam(Wiersum 1997). Still today, millions of people living in and around the forestenvironment in the tropics depend on forests to a large extent (Byron and Arnold 1999).Forests are sources of food, fuel wood, timber, construction wood, and the like.Depending on the cultural background and the management objectives, localcommunities in different parts of the world have developed different indigenousmanagement practices and perceptions of forests. For some communities, forests areimportant not only for subsistence, but also for their spiritual life, which may influencethe way they manage the forest (Byron and Arnold 1999). In any case, people modifythe floristic composition and structure of forest during the process of use in order to getthe best of goods and services (Wiersum 1997; Bakes 2001; Straede et al. 2002). Theindigenous management practices may include several activities such as conservingsome patches of forest, sparing or planting desirable species, introducing new species,eliminating competing species, thinning to protect the forest from fire, mulching,stimulating fruit production, etc. (Wiersum 1997). Such forest management by localcommunities was sustainable and contributed greatly to the conservation of biodiversityand protection of the environment (Bakes 2001; Long and Zhou 2001).In Ethiopia, people mainly depend on forests for fuel wood, constructionwood, timber, honey production and grazing. However, the level of dependency andmode of management varies from place to place, depending on the type of product takenfrom the forest. In the montane rain forest areas of SW Ethiopia, where coffee (Coffeaarabica) occurs naturally, the local communities living in and around the foresttraditionally manage the forest for coffee production. Coffee production is an importantland use in the tropics (Perfecto et al. 1996). In most parts of the tropics, the practice ofcoffee production is not older than two to three hundred years (Marano-Vega et al.67