The effects of biochar on soil extra and intracellular enzymes activity

Extra and intracellular enzymes help soil microbes to degrade soil organic matter and plant residues into smaller digestible molecules. The goal of this study was to investigate the reaction of urease, alkaline phosphatase, beta-glucosidase, and aryl sulfatase to two levels of 0.5% and 1% biochar prepared at 200, 400, and 600 degrees C and corn residues in two clayey and sandy soils. The experiment was conducted as a factorial in a completely randomized design with four replications. The results showed that the addition of amendments changed the biochemical properties of calcareous soils with different textures. Soil enzyme activity increased depending on the use level of biochar and soil texture, while the activity of most soil enzymes decreased with the increase in pyrolysis temperature. The highest increase for the activity of urease (314% in clay soil), alkaline phosphatase (693%) at a rate of 1% of corn residue, beta-glucosidase (240% in clay soil) at a rate of 1% of biochar 200 degrees C, and aryl sulfatase (152% in sandy soil) at a rate of 0.5% of biochar 200 degrees C was obtained, while the lowest activity of urease (63% in sandy soil) at the rate of 1% of biochar 600 degrees C, alkaline phosphatase (73%) and beta-glucosidase (8% in sandy soil) at a rate of 0.5% of biochar 600 degrees C, and aryl sulfatase (16%) at a rate of 0.5% of biochar 400 degrees C was observed compared to the control. Therefore, to increase the biological and enzymatic activity of calcareous soils, biochars prepared at lower temperatures should be used.