Abstract:
Soil acidity is one of the main factors that limit agricultural productivity in many parts of the
world. Study was conducted at Southwest showa Ameya District on acidic soils collected from
dominant crop fields of the four selected kebeles in South Westshowa Zone, Ameya District to
determine the status, and extents of acidity, and determination of lime requirements to
neutralize the acidity effects. The selected kebeles were Gulti Bola, Bero Salen, Dire Aroji, and
Kechema Jiran. Field observation, and surveys of the study areas were carried out.
Representative composite soil samples were collected from dominant crops field at (0-20cm)
depth. Soil physicochemical (Texture, BD, pH, organic carbon, TN, Available P, CEC,PBS,
exchangeable acidity, and bases) were analyzed following the standard procedures. Lime
incubation study was carried out to determine amount of lime required to neutralize acidity of
the soil to the targeted pH. Results of the study revealed that soil pH (H2O) ranged from 4.97
to 5.44 which rated as very strongly acidic to strongly acidic in reactions, and the values of soil
textural class of the study areas were Sandy clay loam, and the bulk density of soils of all the
study areas were in medium range. The values of CEC, PBS, AP, OM, and TN of the study areas
were low, due to the low additions of organic matters or litters deposition in the agricultural
croplands, and Continuous removal of basic cations by crops, intensive cultivation that
enhanced leaching of basic cations, and washed away of exchangeable bases by rill, and sheet
erosion .The results showed that incubation of soil using lime/ CaCo3 completely changed soil
pH from very strongly acidic (4.97) to near optimum (pH of 6 to 6.5), and suitable for crop
production. Based on results of incubation study, 9.16 t ha-1, of lime was required for soil of
Gulti Bola, 9.47 t/ha for soil of Bero Salen, 9.53 t/ha for soil of Dire Aroji, and 9.75 t/ha of lime
for soil of Kechema Jiren kebeles required to be applied to raise soil pH to the target pH values
of 6 to 6.5.