Investigation of infiltration rate for soil-biochar composites of water hyacinth.

The objective of this short communication is to investigate the interactive effects of CIF, suction and volumetric water content (VWC) on infiltration rate for compacted soil-biochar (BC) composites (0%, 5% and 10%). The biochar was produced from an invasive weed Eichhornia crassipes. Soil parameters such as suction (ψ), VWC, CIF and infiltration rate were monitored simultaneously for 63 days (9 drying-wetting cycles) in those composites. This was followed by statistical modeling using artificial neural networks. Results showed that increase in WH BC content reduced the infiltration rates. The role of CIF in determining the infiltration rate reduced (50-38%) with the addition of BC to soil. Suction played an equal role (36-35%), both for bare soil and for WH BC composites, in determining the infiltration rate. Significance of VWC in determining rate of infiltration increases (14-27%) as the BC content increases. This is more likely, as the addition of BC enhanced the water retention capacity. [ABSTRACT FROM AUTHOR]