The Effects of Sugarcane-Derived Biochar on Phosphorus Release Characteristics in a Calcareous Soil

Abstract

The main aim of this study was to investigate how phosphorous (P) release would change after the addition of combined sinfluence upon soil properties sugarcane residues – derived biochar (B) and P fertilizer in a calcareous clay loam soil after 7 and 120 days of incubation. Biochar was produced from sugarcane residues (S) at the temperature of 400 °C under limited oxygen condition. A full-factorial experiment was performed in a completely randomized design to evaluate the effects of amendment (without amendment, 1% S, and 1% B) and P (0 and 50 mg kg−1) on availability and P release characteristics over incubation period (7 and 120 days). After incubation, the kinetics of P release in soils was determined by successive extraction with Olsen solution in a period of 2 to 768 h at 25 ± 1 °C. Results showed that the difference between cumulative P release in soil treated with S and B, at two incubation times, was not significant (P > 0.05). At both times, the cumulative P release increased by 5 up to 23% as influenced by amendments and P fertilizer. Difference between treatments at 7 and 120 days of incubation was not significant (P > 0.05). The lowest and highest initial amount of P release was found in control soil (14.62 mg kg−1 h−1) and soil treated with P + B (38.26 mg kg−1 h−1), respectively. The maximum and minimum rates of P release were in control soil (0.328 (mg kg−1)−1) and soil treated with P + B (0.203 (mg kg−1)−1), respectively. Also, the lowest and highest initial release rates were observed in control soil (4.79) and soil treated with P + B (7.76), respectively. Biochar addition to soil treated with P increased initial amount of P release and initial release rate of P. Therefore, addition of sugarcane residues –derived biochar to soil treated with P fertilizer can increase P availability in similar calcareous soils.