Organic and inorganic amendments on soil chemical properties at different period of incubation of acidic soil

Soil acidity is a critical issue necessitating urgent attention in most highlands of Ethiopia due to its impact on crop production productivity. Application of organic and inorganic amendments could effectively minimize the problem and improve the fertility level of the soil. Accordingly, a greenhouse experiment was conducted to evaluate the effects of sole and combined applications of lime, FYM, compost and P on soil chemical properties incubated at 20, 40 and 60 days. The treatments were arranged in a completely randomized design with three replications. The results indicated that various treatment combinations raised the soil pH at the 40 days of incubation. All treatments showed increased P availability consistently with increasing time of incubation. Maximum available P was observed at the 60 days of incubation due to application of 8 t FYM ha-1 + 30 kg P ha-1 + 5 t lime ha-1 followed by 8 t compost ha-1 + 30 kg P ha-1 + 5 t lime ha-1. Exchangeable acidity and Al were reduced at the 40 and 60 days of incubation with the application of 30 kg P ha-1 + 10 t lime ha-1 followed by 4 t FYM or compost ha-1 + 15 kg P ha-1 + 10 t lime ha-1. Highest exchangeable Ca was obtained at 20 days of incubation with the application of 30 kg P ha-1 + 10 t lime ha-1 followed by 4 t ha-1 FYM + 15 kg P ha-1 + 10 t lime ha-1. Sole addition of 10 t lime ha-1 elevated ECEC from 19.29 to 22.30 cmolc kg-1 at the 40 days of incubation. Likewise, combined applications of 30 kg P ha-1 + 10 t lime ha-1 improved ECEC of the soil from 19.53 to 24.27 cmolc kg-1 at the 40 days of incubation. Integrated applications of organic and inorganic amendments were found more effective to reduce soil acidity and Al3+ concentration with increasing the fertility of the soil.