Assessment of Soil Fertility Status of Different Types of Soils in Selected Areas of Southern Ethiopia

Abstract

A soil fertility assessment study was conducted in Luvic Calcisols (Siltic), Haplic Calcisols (Chromic), Haplic Calcisols (Humic), Haplic Luvisols (Humic), Andic Lixisols (Humic), Andic Cambisols (Humic), Haplic Lixisols (Siltic) and Haplic Lixisols (Humic) in the southern part of Ethiopia to investigate their fertility status. Soil samples were collected randomly from 0-15cm and 15-30cm depths using augur with three replications on farmers’ fields representing the above soil types. The samples were air dried, crushed to pass 2 mm sieve and analyzed for pH, OC, CaCO₃, CEC, exchangeable bases, total nitrogen, available phosphorus, Zn, Cu, Fe and Mn contents. The results revealed that the above soil properties varied between soil types and depths. The OC and CEC contents were varied between moderate and high, whereas CaCO₃ was ranged from low to high increasing with depth. The total nitrogen content was ranged from low (<0.2%) to medium (0.2-0.5%), whereas available phosphorus was medium (8-18 mg kg^-1 soil). The micronutrients contents were decreased with depth and they were low in most of the soils. Organic carbon was positively correlated with total nitrogen and CEC indicating that application of organic materials can improve soil fertility in these soils. In conclusion, soil fertility management practices that can improve micronutrients and a study on nutrient placement for growth of different crops should be carried out in the study soils.

Keywords: soil depth, soil types, micronutrient, organic carbon, total nitrogen, cation exchange capacity