Abstract

CONTEXT: The sustainability of winter wheat (Triticum aestivum L.) summer maize (Zea mays L.) rotation (W M), which is commonly practiced in the North China Plain (NCP), is threatened by severe groundwater deficits and environmental pollution due to excessive nitrogen (N) applications. OBJECTIVE: Considering the need for protein-rich forages by local livestock operations and the environmental benefits of growing perennial legumes, we propose that an alfalfa (Medicago sativa L.)-based system is worth introducing for field practice in the NCP. METHODS: An integrated evaluation was used in this four-year study to compare the agronomic, economic, and environmental performances of the following four cropping patterns: alfalfa monoculture (AA), alfalfa and silage maize intercropping with or without N input which is designed for local climate condition, maize monoculture with or without N input which is much-discussed as a resources-saving substitution and commonly practiced W M. RESULTS AND CONCLUSIONS: W M obtained the highest aboveground dry matter (DM) productivity (P < 0.05) based on the highest irrigation water and N fertilizer consumption (P < 0.05) which caused considerable soil mineral N (Nmin) accumulation. The production cost of maize monoculture was the lowest as well as the DM yield, nitrogen accumulation and the net revenue compared with other systems (P < 0.05), moreover, there was a great risk of N losses during the offseason period. The alfalfa and silage maize intercropping with a low N input (120 kg ha-1 which is close to local practice for maize season) achieved 26.6%-34.9% more DM yield compared with AA and maize monoculture, and 12.5%-163.9% more N output compared with W M and maize monoculture during four experimental years with same total economic revenue as W M and AA did. The N input in alfalfa and silage maize intercropping dramatically improved the system productivity by assisting intercropped maize growth while did not lead to excessive Nmin accumulation within 0-210 soil layer compared with the intercropping system without N addition. The planting of alfalfa would not affect the water storage in the 0-60 soil layer after maize harvesting each year. For the effects of interspecific competition, the production of the intercropped alfalfa and maize was significantly decreased in 2020 and a three-year period of production is recommended for optimal use of the alfalfa and silage maize intercropping. SIGNIFICANCE: Alfalfa and silage maize intercropping with an appropriate N input, which acquired comprehensive performances in terms of productivity, environmental impacts as well as economic profits, would be an optimal alternative system in the NCP.

Keywords

Intercropping; Monocropping; Alfalfa; Silage maize; Winter wheat-summer maize rotation

Published in

Agricultural Systems
2022, Volume: 195, article number: 103305
Publisher: ELSEVIER SCI LTD

SLU Authors

• Li, Shoujiao

  • Department of Biosystems and Technology, Swedish University of Agricultural Sciences
    
  • China Agricultural University

Sustainable Development Goals

End hunger, achieve food security and improved nutrition and promote sustainable agriculture
Promote sustained, inclusive and sustainable economic growth, full and productive employment and decent work for all
Ensure sustainable consumption and production patterns


UKÄ Subject classification

Agricultural Science


Publication identifier

DOI: https://doi.org/10.1016/j.agsy.2021.103305

Permanent link to this page (URI)

https://res.slu.se/id/publ/114523