Guan'gai paishui xuebao (Sep 2024)
Effect of organic fertilization combined with reduced chemical fertilization on yield, nutrient uptake and nitrogen utilization efficiency of maize
Abstract
【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 increased grain yield and aboveground biomass, but also improved nutrient uptake and accumulation, as well as nitrogen use efficiency. Compared with NPK, SWC40 increased grain yield by 14.69%, 9.88% and 25.62% in 2021, 2022 and 2023, respectively, while no significant differences in these traits were found between JZ30 and NPK. In 2023, the cumulative uptake of nitrogen, phosphorus, and potassium in the grains in SWC40 were 145.64, 38.30 and 38.07 kg/hm2, respectively. Compared with NPK, SWC40 increased cumulative uptake of nitrogen, phosphorus, and potassium in the grains by 38.36%, 56.14% and 46.59%, cumulative uptake of N, P and K in the aboveground part by 64.08%, 84.32% and 84.43%, reaching 311.79 kg/hm2, 69.49 kg/hm2 and 204.22 kg/hm2, respectively. The nitrogen agronomic efficiency, nitrogen partial factor productivity, nitrogen contribution rate and nitrogen apparent utilization rate in SWC40 were 6.80 kg/kg, 15.64 kg/kg, 43.53% and 31.01%, respectively, significantly higher than those in NPK. 【Conclusion】 Reducing chemical fertilization combined with an application of biochar or organic manure was more effective in improving maize yield and nutrient accumulation than combined with fine organic manure. In particular, reducing chemical fertilization by 40% combined with biochar organic manure application was most effective, followed by reducing 30% of chemical fertilization combined with fine organic manure application.
Keywords
