Cinque, Ardol (Prof.)Abebe, Bekele2022-01-312023-11-182022-01-312023-11-181982-02http://etd.aau.edu.et/handle/12345678/29810The geology of the Asela area has been studied In de t a ~ l and the fertility status of the soils in relation t o the f actors of soil formation (parent material, climate, top ogr aphy , organisms and time) examined qualitatively and semiquant itatiVielyo The area is associated with Pliocene and younger volcanics (central and fissur al) and is intensively aff e cted by different episodes of faultingo Basal t s, Trachybasalts , trachytes and acidic pyroclastics are the rocks oc curing in the areao The major soils are the dark-dark brown and the reddish brown soils of the plate au and the dark-browndark ye llowish brown soils of the rifto In general, the rif t s oils have higher plant nutrient s t atus than the plateau soil s o Removal of materials is important on the plate au and addition in the rifto Parts of the plateau and mo s t of t he r i f t f l oor are affected by poor drainageo The abundance of surf ace hindrances on the surface of the rift soils might be attr i buted to t he young age of the rocks in the lattero In te r ms of physical limit ations of the land, both t he lowland and t he plateau have their drawbacks o The cumulative influence of the topography and the climate is found to be dominantly r e s p ons ible for the lateral and vertical variations of the inherent fe rtility of the soilsoenGeologyThesis