Supplementary irrigation and reduced nitrogen application improve the productivity, water and nitrogen use efficiency of maize-soybean intercropping system in the semi-humid drought-prone region of China

作者：Zhengxin Zhao, Zongyang Li, Yao Li, Lianyu Yu, Xiaobo Gu, Huanjie Cai · 发表于：Agricultural Water Management · 年份：2024 · DOI：10.1016/j.agwat.2024.109126 · 被引用次数：32 · 研究领域：Agronomic Practices and Intercropping Systems、Legume Nitrogen Fixing Symbiosis、Agroforestry and silvopastoral systems

Maize-soybean intercropping systems are widespread in North China. However, the combined effects of supplementary irrigation and different nitrogen (N) application rates on the productivity, water use efficiency (WUE), and N use efficiency (NUE) of such systems remain unclear. A field experiment was conducted in a semi-humid drought-prone region in Northwest China in 2022 and 2023 to assess the interaction effects of supplemental irrigation and different N application rates on the crop yields, WUE, and NUE of a maize-soybean intercropping system and a monoculture system. Three cropping systems were used: maize-soybean intercropping, maize monoculture, and soybean monoculture, with two irrigation treatment scenarios (rainfed and supplementary irrigation at 30 mm) and three N fertilizer rates for maize (240, 180, and 120 kgN ha −1 ). The land equivalent ratio (LER), ∆ water productivity ( WP ), ∆ N harvest index ( NHI ), and ∆ N partial factor productivity ( NPFP ) of the maize-soybean intercropping system ranged from 1.06 to 1.11, 1.03–1.11, 1.17–1.34, and 1.16–1.28, respectively, demonstrating higher yields and resource of the intercropping system Supplementary irrigation significantly improved yield and resource use by improving the N complementarity effect and increased the economic by 17.24–31.16 %. A 25 % reduction in the N application rate (180 kgN ha −1 ) for maize increased the NPFP without decreasing the crop yield and WP whereas, a 50 % reduction (120 kgN ha −1 ) sig...