Effect of biochar addition on water-salt distribution and growth of winter wheat in saline soils under brackish water irrigation

To investigate water-saving and yield-improving solutions suitable for saline soils in the Yellow River Delta region, this study was conducted to investigate the effects of biochar addition on water-salt transport and winter wheat growth in saline soils under brackish water irrigation conditions through outdoor pot experiments using local moderately saline soils. Three irrigation water mineralization levels (0, 2, 4 g·L -1 ) were used with two types of biochar (wheat straw biochar and corn straw biochar) and four additions (0, 5, 10, 20 t·ha -1 ), with 21 treatments, each replicated three times. The outcomes demonstrated that soil water content was raised by brackish water irrigation as well as charcoal application. While the application of biochar decreased soil salinity and salinization, irrigation with brackish water increased soil salinity and worsened soil salinization. 2 g·L -1 brackish water promoted the initial growth of winter wheat, but led to yield reduction, while application of biochar promoted the growth of winter wheat and increased yield, with 10 t·ha -1 YC having better effect. In conclusion, irrigation with 2 g·L -1 brackish water and application of 10 t·ha -1 YC is a more effective solution for saline land improvement in this region.