PERIODICAL CHANGES OF SOME SOIL PROPERTIES OF A CALCAREOUS SOIL UNDER FIELD CONDITIONS AS AFFECTED BY DIFFERENT BIOCHAR APPLICATIONS

In this study, the effects of the application of biochars derived from tomato harvest residues on some properties and nutrient concentrations of calcareous soils were investigated. Biochars produced at different pyrolysis temperatures (300, 500, and 700 degrees C) with the duration of 4 hours were applied to the depth of 15 cm at the rates of 30 t/ha to microplots established (50 cm x 50 cm) in field conditions. Soil samples were taken at four soil incubation periods and were analyzed for pH, cation exchange capacity (CEC), plant available and/or extractable K, Ca, Mg, P, Fe, Mn, Zn, and Cu. Mean values showed that soil pH significantly increased with the increasing incubation time and pyrolysis temperature. All other parameters examined in the study were significantly affected by the interaction of incubation time and pyrolysis temperature. Depending on the results, it can be concluded that the biochars produced at different temperatures and the soil incubation periods did not have a significant contribution on the exchangeable cations and the other nutrients of soil. Furthermore, it was observed that the biochar obtained at the pyrolysis temperature of 700 degrees C generally had a negative effect.