Effect of biochar on some soil properties after 4-year application and its effect on growth, yield and nutrient uptake of wheat grown on an alkaline soil

This study investigated the impact of biochars on some soil properties, plant growth, nutrient concentrations and uptakes after a 4-year application. Biochars produced at pyrolysis temperatures of 300, 500, and 700 degrees C were applied to the microplots at a rate of 30 t ha(-1) in 2017. In 2020-2021 growing season, basal fertilizations were applied to the microplots before sowing wheat. The results showed that biochar applications had no significant effect on soil pH, EC, and CaCO3, although they increased cation exchange capacity and organic matter content. Available nutrient concentrations were not affected positively in general. While biochar applications enhanced vegetative growth and the straw yield, the grain yield decreased. Moreover, straw and grain nutrient concentrations did not vary with biochar applications, but the total nutrient uptake increased. Positive correlations were determined between the carbon sequestration potential of the soils and total yield. In addition, it was revealed that the effect of biochar applications on soil physical properties did not create a significant variation. According to the principal component analysis, the properties with the lowest effect were found to be EC of the soils. Findings from this study indicated that biochar did not directly affect plant growth by providing nutrients to the soil or increasing the amount of available nutrients; however, it can stimulate plant growth by improving some soil characteristics.