: “traditional management and driver factors of woody species diversity on farm lands: the case of Hulbarege Woreda, Silte zone southern Ethiopia’

Abstract

Woody species are found in farmland in various forms of spatial and temporal arrangements with other agricultural components, and have ecological and socio-economic roles to the farmers. To assess farmland woody species diversity and traditional management at Hulbarege woreda insouthern Ethiopia, this study was conducted. Atotal of 24 key informants (KI), 3 from each village were selected by ranking and were used to categorize the village households (HH) in to three wealth categories. Moreover, simple random sampling within wealth category was used to select a total of 120 sample of HHs for interview. Data on woody species diversity in the homestead, crop fields and grazing/pasture land use system were collected. A complete enumeration of woody species in homegarden which has the average area of 0.27 ha, Whereas, 50 m × 100 m sampling quadrates in crop field, and 40 m × 40 m sample quadrates for grazing lands were used. Number of individuals per plot, DBH, and plot area were measured and recorded. The structure and composition of woody species through important value index (IVI), basal area, and diversity indexes were calculated. The result of the study showed that a total of 29 trees species and 2 shrubs species belonging to 18 families were recorded from homegardens, crop fields and grazing/pasture land use system in the study sites. The total number of tree species in the homegardens, crop fields and grazing land were 24, 18 and 10 respectively. The family Fabaceae 10 species (32.3 %), Moraceae 3 species (9.7 %) the least frequent families were Anacardiaceae, and Myrtaceae represented by 2 species each (6.5%). However, many of the families were represented by single species. From this species, 18 species (58.1%) were indigenous and 13 species (41.9%) were exotic. Generally the study revealed that the woody species Shannon and Evenness diversity indices were higher in homegardens, than crop fields and grazing/pasture land. At the study sites,there was a labordivision in woody species management activities, manage woody species in their farmlands for the purpose of improving soil fertility, fodder, fuel wood, timber, shade, construction, etc. The management practices employed at different land use includes branch pruning, pollarding, lopping, protection and coppicing. The socio-economic factors that influence management of woody species in farmlands across the study were found to be educational background, wealth status, sizes of homegarden were significantly positively correlated (P< 0.05) with the woody species richness. Therefore, based on this study it can be concluded that woody species retaining/management practices such as in grazing land must be promoted where species diversity is very limited due to free grazing