INTERCROPPING: FEED MORE PEOPLE AND BUILD MORE SUSTAINABLE AGROECOSYSTEMS

Highlights

• Intercropping is a useful practice when agricultural sustainability is emphasized.

• We integrate biodiversity-ecosystem functioning and intercropping.

• Intercropping optimizes ecosystem services such as stabilizing yield and reducing use of chemicals.

• Intercropping benefits are attributed partly to complementarity and selection effects.

• Application of ecological principles is key to sustainable agricultural development.

Abstract

Intercropping is a traditional farming system that increases crop diversity to strengthen agroecosystem functions while decreasing chemical inputs and minimizing negative environmental effects of crop production. Intercropping is currently considerable interest because of its importance in sustainable agriculture. Here, we synthesize the factors that make intercropping a sustainable means of food production by integrating biodiversity of natural ecosystems and crop diversity. In addition to well-known yield increases, intercropping can also increase yield stability over the long term and increase systemic resistance to plant diseases, pests and other unfavorable factors (e.g. nutrient deficiencies). The efficient use of resources can save mineral fertilizer inputs, reduce environmental pollution risks and greenhouse gas emissions caused by agriculture, thus mitigating global climate change. Intercropping potentially increases above- and below-ground biodiversity of various taxa at field scale, consequently it enhances ecosystem services. Complementarity and selection effects allow a better understanding the mechanisms behind enhanced ecosystem functioning. The development of mechanization is essential for large-scale application of intercropping. Agroecosystem multifunctionality and soil health should be priority topics in future research on intercropping.

Graphical abstract

Keywords

agroecosystems / crop diversity / intercropping / interspecific interactions / sustainable agriculture

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Acknowledgements

The study was funded by the National Key Research and Development Program of China (2016YFD0300202) and the National Natural Science Foundation of China (31430014, 31971450).

Compliance with ethics guidelines

Hao Yang, Weiping Zhang, and Long Li declare that they have no conflicts of interest or financial conflicts to disclose. This article does not contain any studies with human or animal subjects performed by any of the authors.

RIGHTS & PERMISSIONS

The Author(s) 2021. Published by Higher Education Press. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0)