Effect of organic fertilization combined with reduced chemical fertilization on yield, nutrient uptake and nitrogen utilization efficiency of maize

【Objective】 Reducing chemical fertilizer use while increasing organic fertilization has been proposed as a solution to mitigate nonpoint source pollution and soil degradation caused by chemical fertilizers. This paper presents the results of an experimental study on the effects of this approach on yield, nutrient uptake, and nitrogen use efficiency of maize in dryland areas of Shanxi Province. 【Method】 The experiment was conducted from 2021 to 2023. The fertilization treatments were: 100% of chemical fertilization (NPK), reducing chemical fertilization by 40%, 30% and 20% combined with an application of biochar organic manure (SWC40, SWC30, SWC30), or an application of organic manure (JZ40, JZ30, JZ20), respectively. The control was no fertilization (CK). During the experiment, we measured the yield, nutrient uptake and nitrogen utilization efficiency of the crop consecutively for three years. 【Result】 A rational combination of chemical fertilization reduction and organic fertilization not only significantly