Abstract
To clarify the responses of soil carbon and nitrogen to biochar amendment under deficit irrigation, a two-year field experiment was conducted in wheat fields of northern Xinjiang with a completely randomized block design. Four biochar rates (0, 10, 20, 30 t/ha, namely B0-B3) and three irrigation regimes were set. Irrigation volumes were 4500, 4050 and 3600 m3/ha in 2021 (namely W0, W1, W2), and adjusted to 4500, 4050 and 3825 m3/ha in 2022 (namely W0, W1, W2'). Two-way ANOVA was used to analyze the main and interactive effects of biochar dosage, irrigation level and experimental year on all indicators. The results revealed that biochar application significantly increased soil organic carbon (SOC) and total nitrogen (TN) contents. Biochar and irrigation exerted significant interactive effects on SOC in the second year (P 3/ha with a 10% reduction. This matching pattern can achieve efficient water saving and stable soil carbon sequestration in irrigated farmlands.