Nitisols cover an extensive area of the agricultural landscape in the Ethiopian highlands. This study outlines the morphological and physico-chemical properties, and the mineralogical and total elemental composition of some Nitisol profiles based on soil survey at 250 m resolution. Analytical data of 46 Nitisol profiles were studied for soil pH, organic carbon (OC) and some macro and micronutrients, and mineralogical and total elemental composition. Results showed that Nitisols of the Ethiopian highlands differ in some fundamental ways from the pedogenetic characteristics often referred to in the mainstream soil science literature. The soils in this study are strongly to moderately acidic with pH of 4.8-6.7, and very low in OC, TN and sulfur (S) with mean values of 2.05%, 0.18% and 0.94 mg/kg. But levels of available phosphorus (AP) and exchangeable K showed wide variation (2.40 to 26.40 mg/kg P and 0.07 to 2.77 cmol (+)/kg K), reflecting differences in parent materials and land use. Considering micronutrients, the soils are very high in iron (Fe), manganese (Mn) and zinc (Zn) but severely deficient in copper (Cu) and boron (B). Conversely, the soils are very high in CEC (mean 41.93, range 26-57 cmol (+)/kg) and base saturation (mean 73%, range of 50-95%), and mean silt/clay ratio of 0.38 in the Ap horizon is rated high. Mineralogical composition of primary minerals (chiefly feldspars) and 2:1 phyllosilicates (mainly mica) in the clay fraction, suggests that the soils are still young and cannot be qualified as “highly weathered soils” in contrast with other tropical Nitisols. At a local level, the results suggest that sustainable agricultural production on these soils depends on the replenishment of organic matter and application of fertilizers in proper balance and right amounts. Also, the distinct characteristics of Nitisol profiles described provide additional diagnostic criteria to distinguish subunits of Nitisols (i.e., third level) under the WRB system of classification.
