Impact of Biochar Particle Shape and Size on Saturated Hydraulic Properties of Soil

Abstract

properties of biochar, which is made out of a variety of biomass materials, can impact water movement through amended soil. The objective of this research was to develop a decision support tool evaluating the impact of the shape and the size distribution of biochar on soil saturated hydraulic conductivity (Ksat). METHODS AND RESULTS: Plastic beads of different size and morphology were compared with biochar to assess impacts on soil Ksat. Bead and biochar were added at the rate of 5% (v/w) to coarse sand. The particle size of bead and biochar had an effect on the Ksat, with larger and smaller particle sizes than the original sand grain (0.5 mm) decreasing the Ksat value. The equivalent size bead or biochar to the sand grains had no impact on Ksat. The amendment shape also influenced soil hydraulic properties, but only when the particle size was between 3-6 mm. Intra-particle porosity had no significant influence on the Ksat due to its small pore size and increased tortuosity compared to the inter-particle spaces (macro-porosity). CONCLUSION: The results supported the conclusion that both particle size and shape of the amended biochar impacted the Ksat value.