Introduction
The central and northern highlands of Ethiopia have experienced a complete removal of every plot of land with indigenous plants and converted to either farmland, settlement or grazing land. The patches of forests in these landscapes are only found as a pocket of protected areas and in church yards. Southwest Ethiopian landscapes are relatively better in forest coverage as compared to the central and north as it blended with mosaic of forests which comprises forest coffee farm, agroforestry, shade trees, hedge rows and communal forest for the source of non-timber forest products. Observing patches of natural forest patches in these areas is also not uncommon. These fragmented patches are purposely preserved by indigenous communities and are natural places used in traditional rituals and customs that bond culture and nature. Apart from fragmented forests distributed in agricultural landscapes, there are a few larger natural forest stands restricted to river side and on rocky areas. More than half of these forest stands are suffered from human disturbance for coffee management, cattle grazing and timber extraction. A few canopy tree species preserved as a coffee shade in coffee managed forests are considered by many people as a forest. Thus, our researchers claim the contribution of coffee farm to the existence of some canopy trees without exploring trade-offs. Here is the fact: Farmers have preserved some canopy tree species including some understory legumes such as Milletia ferrugina and Albizia schinperiana, which are considered to be important for promoting soil fertility. These farmers’ activities have over-appreciated by domestic conservation workers and a few researchers. While this preservation of some tree species by farmers for coffee shade and soil fertility has potential benefits for biodiversity and the provision of ecosystem services, it should not be taken as achieving the conservation of the full biodiversity of these afromontane forests. This is because farmers are also engaged in a gradual thinning of understory shade tolerant trees (e.g.Chionanthus mildbraedii., Vepris daniellii., Macaranga capensis and Olea capensis subsp. Macrocarpa), and in most areas of these forest they also are selectively removing trees (e.g. Pouteria adolfi-friederic and Cordia africana) in their coffee farm to produce timber for sale, and these resulted in increasing convergence of the composition of tree stands with dominance by the same unexploited and disturbance-benefiting species of Croton macrostachyus, Maesa lanceolata, Albizia gummifera and Milletia ferruginea. The rest of forest patches which are not used as coffee forest embedded in agricultural dominated landscapes, particularly in the higher altitude, are also clearly threatened by gradual fragmentation, selective timber extraction and suffered from establishment of homogenous stands of low tree species diversity dominated by pioneer tree species as well as a range of vine species (e.g. Gouania longispicata, Sericostachys scandens, Urerea hypselodendron, Stephania abyssinica, Dioscorea bulbifera, Peponium vogelii, Scutia myrtina, Lagenaria abyssinica and Combretum paniculatum) that are able to invade forest gaps. Shrubs that are typical of more open woodland or other disturbed woody habitats (e.g. Vernonia spp., Hibisus spp., Cyathula sp., Acanthus spp and Rubus spp) were also notably more abundant in these forests which indicates that the forests are gradually changing to woody habitats which might be different in structure from the pervious natural forest stands. These threats are not very much appreciated by our researchers and conservation communities. So, should we wait until natural afromontane forest type converted to another homogenous stand of trees from opportunistic species which do not fully support ecosystem services? Or should we evaluate synergies and trade-offs of social-ecological interaction at spatial and temporal scale and find a sustainable solutions? |