Optimizing Fertilizer Management Practices in Summer Maize Fields in the Yellow River Basin

Abstract

This study aims to examine the impact of combined irrigation and fertilizer control on the summer maize yield, nitrogen use efficiency (NE), and nitrogen leaching (NL) in the Yellow River Basin. Based on the measured data from the field summer maize experiment in 2021 and 2022, a water-nitrogen movement model was constructed for ‘Zhengdan 958’ maize under two irrigation methods (wide furrow irrigation (G) and border irrigation (Q)), three fertilizer rates (120 kg/ha (N1), 220 kg/ha (N2), and 320 kg/ha (N3)), and three fertilizer frequencies (1 (T1), 2 (T2), and 3 (T3)), yielding 18 total treatments. Calculation of nitrogen leaching was based on water nitrogen transport modeling. The study then analyzed the factors and their combined effects. A multi-objective optimization genetic algorithm (NSGA-II) was established to evaluate maize yield, nitrogen use efficiency, and nitrogen leaching. The results indicate that the determination coefficients between simulated and measured water, nitrogen values exceeded 0.74. The rate optimized HYDRUS model effectively simulated the soil solute movement. The interaction of the irrigation method, fertilizer rate, and fertilizer application frequency did not significantly affect yield and nitrogen leaching, but did significantly impact nitrogen use efficiency (p −1 and 17.64 kg/ha, respectively. These findings can guide summer maize cultivation in the Yellow River Basin and assist in reducing nitrogen surface source pollution.

Keywords

• yield
• nitrogen use efficiency
• nitrogen leaching
• NSGA-II
• HYDRUS
• irrigation method