Characterization of Biochar Produced at Different Temperatures and its Effect on Acidic Nitosol of Jimma, Southwest Ethiopia

Abstract

Physical and chemical properties of the biochar varied as a function of feedstock selection and pyrolysis temperatures. Biochar additions to acidic soils have the potential to improve soil fertility and crop yield. Biochar materials were produced from coffee husk and corn cob at temperatures of 350 and 500°C and characterized by their physical and chemical properties. These were mixed with acidic soil at the rates of 0, 5, 10 and 15 t haG1 and were laboratory incubated for 2 months at ambient temperature to examine changes in soil properties. Types of feedstock used at two different pyrolysis temperatures and application rate had no significant effects on soil textural classes but showed highly significant effects (p<0.01) on soil pH, Electrical Conductivity (EC), Cation Exchange Capacity (CEC), Organic Carbon (OC), Organic Matter (OM), Total Nitrogen (TN), exchangeable cations and available phosphorous. Application of coffee husk biochar showed relatively better improvement in soil chemical properties (pH, EC, CEC, OC, OM, TN, exchangeable cations and available phosphorous) than corn cob biochar at all application rates. The highest values of chemical properties were recorded when coffee husk biochar produced at 500°C temperature was applied at a rate of 15 t haG1 . Therefore, we generated an evidence that application of biochar is very important to improve physical and chemical properties of acidic soil