Long-Term Effects of Single Application of Biochar on Physical and Hydrological Properties of Crosby Silt Loam Soil in Central Ohio, USA

PurposeVery few studies have been done on the long-term effect of one time biochar application on soil physical and hydrological properties. The current investigation aims to know the alterations in infiltration rate (IR), soil water content (SWC) at different potential, water stability of aggregates, etc. caused after 6 years of application of oak wood biochar in Crosby silt loam soil of temperate ecosystem.MethodsThe trial was carried out using a complete randomized block design with three treatments: B0 (no biochar), B25 (biochar at 25 Mg ha-1), and B5 (biochar at 5 Mg ha-1) and six replications. After 6 years, soil's physical and hydrological characteristics were measured.ResultsThe application of B25 resulted in the highest total porosity compared to the other treatments which in turns results in lower bulk density. B25 also enhanced the water stability of aggregates by 4.1%, as compared to the B0. B25 significantly enhanced soil water retention at all measured soil water potentials (0, -6, -10, -33, -100, and -1500 kPa) except for -1500 kPa (0-10 cm), -6 kPa (10-20 cm), and 0 kPa (10-20 cm) relative to B0. The highest increase in soil water content was recorded for B25 at 0 kPa (9.2%) followed by that at -6 kPa (7.4%). While, the B25 increased the mean hydraulic conductivity by 55.9% over control, B5 resulted in a 15.5% increase. The IR of soil also increased under B25 and B5 over B0 by 15.5 and 5.0%, respectively.ConclusionsBiochar application in Crosby silt loam soil can enhanced soil physical and hydrological properties and maintained in long run.