| In order to investigate the effects of combined application of biochar and organic fertilizer on maize yield and soil nutrients in saline alkali land, a field plot experiment was conducted, with a total of five treatments: CK (traditional fertilization), T1 (traditional fertilization + organic fertilizer 3.75 t · hm-2), T2 (traditional fertilization + biochar 2.5 t · hm-2 + organic fertilizer 3.75 t · hm-2), T3 (traditional fertilization + biochar 5.0 t · hm-2 + organic fertilizer 3.75 t · hm-2), T4 (traditional fertilization + biochar 7.5 t · hm-2 + organic fertilizer 3.75 t · hm-2). The results showed that: (1) The combination of biochar and organic fertilizer had a significant yield increasing effect, with yield increasing rates ranging from 8.77% to 16.41% for each treatment, with T4 treatment showing the best yield increasing effect. T2 processing has the best profit, with a net profit increase of 711.94 yuan · hm-2 compared to the control. (2) In terms of reducing soil salinity and adjusting soil pH, the application of biochar is more effective than the application of organic fertilizer alone. The T3 treatment has the best improvement effect, with a soil salinity reduction rate of 23.85% and the lowest pH of 7.64. In terms of improving available nutrients, increasing organic matter and total nitrogen content, T4 treatment had the best effect, with hydrolyzed nitrogen, available phosphorus, available potassium, organic matter and total nitrogen content reaching their maximum values, increasing by 38.41%, 122.03%, 47.96%, 42.84% and 17.86% respectively compared to the control. |